2006年度日本冷凍空調学会年次大会 講演題目「Particle Swarm Optimization の適用による単段型吸着冷凍機の最適設計」

平成10年度日本冷凍空調学会学術講演会 講演題目「LNG 冷熱を用いた多段動力回収システム —アンモニア・水混合媒体を用い たサイクルのエクセルギー評価—」

記述言語：英語  

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記述言語：日本語  

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記述言語：英語  

This paper presents theoretical and experimental investigation of an adsorption cooling system to predict the cycle performance of one bed adsorber based on the equilibrium condition. For this particular study, activated carbon-ethanol pair was chosen as the adsorbent-refrigerant pair because of a high adsorption capacity of activated carbons against ethanol. The experiment was conducted on five different pre-cooling and pre-heating settings. The experiments carried out were divided to two sections. First, the preliminary experiments were carried out on two extreme conditions. For the first extreme condition, the adsorption and desorption process were carried out without pre-cooling and pre-heating. Whilst for the second extreme condition, the adsorbent was pre-cooled and pre-heated until the adsorbent reach adsorption and desorption temperature. Then the experiments were carried out with three different time of pre-cooling/pre-heating time which was selected based on the preliminary experiments. The heat balance were analyzed critically and the optimum cycle time, namely the pre-cooling and pre-heating time for each adsorption and desorption process is discussed by identifying the suitable adsorbent pressure and temperature of the system.

DOI： 10.11322/tjsrae.15-26RE

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2009.10.005

記述言語：英語  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2009.01.005

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2008.12.002

記述言語：英語  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.renene.2005.05.003

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.renene.2004.05.010

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

記述言語：英語  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S0360-5442(00)00002-5

掲載種別：研究論文（学術雑誌）   出版者・発行元：Applied Energy  

Upgrading low-grade industrial waste heat to higher temperatures plays a crucial role in improving energy efficiency and advancing sustainable development. In this study, a comprehensive dynamic performance analysis of a dual-bed adsorption heat transformer (AHT) system driven by a large pressure jump is conducted to upgrade the low-grade waste heat. The AQSOA-Z05/water working pair is investigated under constant flow output (CFO) and constant temperature output (CTO) modes. The theoretical maximum temperature lift potential governing adsorbent selection and operating conditions is thoroughly explored. Compared to the CFO mode, the CTO mode is found to provide more stable and controllable high-temperature output suitable for practical applications while achieving a higher specific heating power. Further, key parameters influencing system performance, such as adsorption connecting pipe diameter, target temperature lift, ambient and waste heat temperatures, are systematically analyzed under the CTO mode. Ambient temperatures of 0–30 °C facilitate stable operation, whereas waste heat below 70 °C leads to performance deterioration. To bridge the variable flow output under the CTO mode with heat load demands, integrating a heat storage tank and control system is suggested. The insights provided are expected to furnish valuable guidelines for the design and optimization of the AHT system, thereby facilitating more effective utilization of waste heat and contributing to sustainable industrial practices.

DOI： 10.1016/j.apenergy.2024.124478

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出版者・発行元：Applied Thermal Engineering  

The surging demand for air conditioning, especially in hot climates, underscores the urgency of strategies aimed at curbing fossil fuel reliance and fostering energy saving strategy. Despite the longstanding utility and advantages of the conventional mechanical vapor compression refrigeration system, sustainability hurdles persist owing to its pronounced electricity demand. While evaporative cooling, harnessing water evaporation, emerges as a more efficient alternative, its efficacy is contingent upon environmental conditions. Addressing this, dew-point evaporative cooling (DPEC) presents an innovative direction, showcasing superior efficiency by directing supply air into a wet channel. This study delves into the thermodynamic losses within a counter-flow configured DPEC system, employing a transient entropy generation model rooted in the second law of thermodynamics to provide a comprehensive analysis of DPEC's performance. Key findings that emerged from this study reveal that (1) the transient entropy generation is intricately distributed across different layers of the dew point evaporative cooling (DPEC) system, including dry air, wet air, the channel plate, and the water film; (2) Parametric analyses highlight the significant impact of factors on entropy generation, inlet air temperature has a minimal effect on system efficiency, but higher temperatures increase thermal losses. Excessive humidity limits evaporative potential, while low humidity significantly increases entropy generation. The system performs optimally at a working ratio of 0.3 and lower air velocities (within the inlet air velocity range of 0.6 to 2.2 m/s). Channel length has little impact, while the system is more sensitive to channel height, with a height of 2.5–3.5 mm being conducive to better performance. Experimental validation demonstrates the model's accuracy in predicting system performance. The research contributes to a deeper understanding of DPEC systems, offering insights for achieving optimal operating conditions and enhancing overall efficiency in the pursuit of sustainable development.

DOI： 10.1016/j.applthermaleng.2024.124443

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出版者・発行元：Journal of Porous Materials  

This study not only explores the fabrication of rare zeolites from waste pumice and examines the impact of aging on their porosity and adsorbate uptake but also provides practical insights for waste management and agricultural applications. The use of organic templates was avoided in the synthesis due to their high cost and pollution associated with their calcination. Potassium-exchanged gonnardite (K-Gon) and perlialite were hydrothermally synthesized using KOH. Interestingly, we found that increasing the magnetic stirring duration during synthesis had a significant impact on the products’ surface area and pore volume, leading to an increase from 39 m²/g to 182 m²/g and from 0.11 cm³/g to 0.30 cm³/g, respectively. This improvement resulted in an increased adsorbate uptake at higher pressures. At shorter stirring times, potassium-exchanged gonnardite zeolite with tetragonal symmetry was the most prevalent phase, which differs from the orthorhombic symmetry of Na-rich gonnardites. Additionally, we observed that the product content of perlialite (hexagonal symmetry) increased with longer stirring durations while K+ ions decreased. This suggests that increased stirring time can increase the disorderliness of extra framework particles, as seen in perlialite, as opposed to K-Gon. Longer stirring time produces other zeolites with slightly less K but improved textural properties, which can potentially accommodate more water. It is also useful for agricultural purposes, such as keeping soils moist and decontaminated, and as adsorbents for greenhouses’ air conditioning.

DOI： 10.1007/s10934-024-01663-z

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出版者・発行元：Advanced Powder Technology  

This research reports conventionally-synthesized-zeolites with comparatively large surface area (SSA) and water-uptake prepared solely from waste-pumice. Notably, the synthesis process avoided using additional commercial raw materials, organic templates, and high temperatures, so that the process was less costly and ecofriendly. To optimize the process, the synthesis time was varied, and the mixture of the raw material and alkaline solution was stirred for 12 h. The zeolite mother liquor was also recycled. Water adsorption experiments were carried out using gravimetric measurements. The Na-P1-rich zeolite product with an optimal water uptake of 0.256 g/g was synthesized after 48 h of hydrothermal activation (H). On the other hand, the product's optimal SSA of 186 m2/g was achieved after 36H under similar conditions (rich in faujasite). Adsorption isotherms showed that water uptake increased with activation time and with the inclusion of mother liquor recycling. Furthermore, recycling resulted in a product with enhanced SSA compared to its precursor. Un-recycled products exhibited relatively high-water uptake both at low and high relative-pressure, while the recycled product had a high uptake at high relative pressure. All products could be used in adsorption heat pump (AHP) applications (air conditioning) suited for high relative humidity (RH) environments. However, high-synthesis-time non-recycled products could also work for low RH AHP applications.

DOI： 10.1016/j.apt.2024.104713

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出版者・発行元：Journal of Materials Science  

Air-conditioning (A/C) systems in tropical regions are characterized by significant energy consumption for latent load handling. Decoupling of the latent load from the A/C units can be achieved using a dedicated dehumidification system while the A/C systems handle only the sensible heat at high efficiencies. Desiccants are widely used in industry, and adsorbent materials that exhibit a unique isotherm shape, i.e. "S shape", have been developed extensively. Recently, activated carbons (ACs) have been discussed as effective adsorbents for dehumidification applications. Although pristine ACs are considered to be hydrophobic materials, certain surface treatments initiate surface phenomena that promote water vapour uptake at relative pressures above 0.4 due to microdroplet aggregation. This work reviews and reports the latest developments of sustainable activated carbons for dehumidification using a multiscale approach spanning from the sustainable precursor selection, “green” activation processes and surface functionalization, adsorption thermodynamics, and system-level developments. With the focus on sustainability, we demonstrate that water adsorption and viable adsorption range are gradually improving with the progressing research, and they are reaching operational values required for practical use. The unique adsorption process of water onto ACs is further explained in detail using solvation theory on the microdomains created by the hydrophilic functional groups while providing clarification of thermodynamic properties adopting the specificities of water/activated carbon adsorption pair. The predicted performance of a desiccant dehumidification system utilizing activated carbon is evaluated using the local weather conditions of numerous major cities worldwide. The highest dehumidification performances of activated carbon, as indicated by the unified SDP (specific dehumidification power) value, are reached particularly in cities that suffer from high humidity and temperature the most proving the viability of this cheap and sustainable material. Graphical abstract: (Figure presented.)

DOI： 10.1007/s10853-024-10265-8

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出版者・発行元：AIP Conference Proceedings  

Adsorption thermal energy storage (aTES) is one of the possible technologies that could help to eliminate our dependence on fossil fuels. The advantages of the adsorption systems lie in the possibility to supply hot as well as cold, and the fact that the aTES systems have negligible energy losses over time and therefore are also suitable for seasonal storage. Selection of the right adsorption pair to store the maximum amount of energy is then the key factor for high-efficiency system. In this work, we introduce the basic principles of the adsorption thermal energy storage and analyze the pivotal aspects for the high-performance adsorption thermal energy storage, not too dissimilar from the adsorption heat pumps. The adsorbate of choice for the storage applications remains water with the highest energy density coming from high enthalpy of vaporization and high polarity of the water molecules. Modern high-yield adsorbents for adsorption thermal energy storage are nearly without any exception tailored microporous materials with high water affinity such as microporous silica, zeolites and zeolite like materials and metal organic frameworks (MOFs).

DOI： 10.1063/5.0228013

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出版者・発行元：AIP Conference Proceedings  

In this simulation, convection heat transfer, friction factor, and flowing TiO2/water nanofluids inside the double tube concentric heat exchanger for both plain and insert twisted tape insert was approached by the numerical estimation using fluent Ansys software. The numerical were carried out in the Reynolds number range from 5000 to 10,000, the particle concentrations used 0.1%, and twisted tape insert with a ratio of 7 was used. As the Reynolds number rises, the nanofluid Nusselt number increases as well. The findings demonstrated that, compared to a simple tube heat exchanger, the twisted tube heat exchanger showed increased heat transfer, and the addition of nanofluid TiO2/water can increase the Nusselt number.

DOI： 10.1063/5.0228360

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出版者・発行元：International Journal of Heat and Mass Transfer  

In adsorption processes, gaseous molecules are trapped on the surfaces of the solid adsorbent because of the surface forces. In contrast to bulk liquid or gaseous phases, fluids in adsorbed phase display distinctive characteristics. Understanding of the adsorbed phase and developing accurate models for its thermodynamic properties are crucial in assessing adsorption processes. Most existing models for the adsorbed phase often portend thermodynamic inconsistencies since they invoked numerous assumptions (e.g., ideal gas behavior of the adsorbate and negligible adsorbed phase's specific volume). We thoroughly propose and examine thermodynamically consistent models for adsorbed phase thermodynamics (specific heat, enthalpy, and entropy). A new specific heat capacity expression is derived accounting for the typically neglected adsorbed phase specific volume. Adsorbed phase properties calculated using these new models exhibit behaviors closer to the liquid phase compared to the gaseous phase. In contrast, enthalpy and entropy of the adsorbed phase calculated using the models available in the literature have been found exceeding the corresponding gaseous phase boundaries at higher pressure/coverage. The proposed correlations are applied to the thermodynamic characterization of a newly developed adsorbent material, activated carbon MSF-A30M with ethanol adsorbate, and compared against other activated carbons reported in the literature. The comparison shows consistent values of thermodynamic properties, well within the theoretical boundaries. As a practical application of the new correlations, we applied them to evaluate the performance of the adsorption heat pumps using 30 different working pairs. Accurate evaluations of the entropy, which is a thermodynamic state property, will lead to improved entropy generation calculations using the classical thermodynamic approach. This work will significantly contribute to improved tracking of thermodynamic losses in adsorption processes, from low coverage to near saturation pressures (details on thermodynamics loss evaluations of the cycles not covered in the present work).

DOI： 10.1016/j.ijheatmasstransfer.2024.125579

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出版者・発行元：International Journal of Energy Production and Management  

The investigation of the substantial impact of natural gas composition on the parameters for operation as well as the performance of centrifugal gas compressors in gas turbine power plants is presented in this paper. The efficiency and dependability of these compressors are greatly impacted by the composition of natural gas, which is defined by the different proportions of methane, ethane, propane, butane, nitrogen, carbon dioxide, and other trace elements. This paper attempts to outline the complex effects of different gas compositions on compressor efficiency, maintenance needs, and overall plant operations through a thorough examination. Important factors to consider include how compressor longevity and performance are affected by gas density, energy content, corrosive components, moisture content, inert gases, and combustion characteristics. In addition, the study examines mitigating tactics to deal with issues brought on by variations in gas composition, including material compatibility, adaptive technologies, monitoring systems, and maintenance plans. This study offers insightful information that is crucial for maximizing the dependability and efficiency of centrifugal gas compressors in gas turbine power plants under various natural gas compositions.

DOI： 10.18280/ijepm.090307

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記述言語：英語   出版者・発行元：iScience  

Understanding changes in thermodynamic and transport properties during adsorption is crucial for the thermal management of metal-organic frameworks, which also imposes significant challenges for improved performance and energy density of adsorption system. Because of phase transitions in the intermolecular interactions involved in the adsorption phenomena, transport properties including the thermal conductivity exhibit interesting behaviors, yet fully understood. This study employs detailed molecular dynamics simulations to replicate the methane/Cu-BTC adsorption phenomenon for the evaluation of their thermal conductivities across different pressures and temperatures. The molecular simulations show that the thermal conductivities of both the adsorbent (Cu-BTC) and adsorbate (methane, adsorbed phase) vary notably during adsorption processes. Using the concepts of the change in the degree of free movements of the adsorbate molecules and atomic vibration of adsorbent, the reduction of the adsorbate thermal conductivity (∼70–93%) and increase thermal conductivity of the adsorbent (up to 3 times) in Cu-BTC+CH4 pair are explained.

DOI： 10.1016/j.isci.2024.110449

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PubMed

出版者・発行元：Thermal Science and Engineering Progress  

Light trapping is a popular method used to improve the performance of photothermal absorbers. Granular structures are one of the light-trapping structures currently developed. In this paper, a review on the working principle and types of granular structures is presented. Furthermore, recent findings pertaining to the innovations of granular structures as photothermal absorber materials are discussed. This paper presents the extent of research and development in this area and identify the potential of granular structures as photothermal absorbers. The performance metrics used to evaluate the performance of photothermal absorber materials are described, which will be useful as a reference for making valid and reliable measurements. Moreover, this paper presents the material properties, types of fluid flow, and energy loss management that need to be considered when analyzing the performance of photothermal absorbers, which will serve as a reference for scientists and engineers for future sustainable technology development.

DOI： 10.1016/j.tsep.2024.102689

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掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Heat and Mass Transfer  

Adsorption heat transformer (AHT) cycle is capable of upgrading the low-grade waste heat to a higher temperature. The maximum temperature lift of the AHT cycle can represent its theoretical performance limit. However, such a metric is currently absent from the literature due to the scarcity of fundamental studies on the heat upgrading sorption cycles. Therefore, in the present study, three models are proposed to derive the ‘maximum temperature lift’ of a typical AHT cycle: (i) heat engine heat pump representation, (ii) the 2nd law of thermodynamic formulation, and (iii) complete preheating. The first two models are developed based on the reversible cycle approach, whereas the 3rd model incorporates adsorbed phase properties. Thus, the first two models might be considered as the formulations for the thermodynamic temperature limit (lift) of an AHT cycle while the 3rd model is specific to the nature of a particular adsorbent + adsorbate pair which might be close to practical applications. The reversible models predict a maximum temperature lift of 22 ∘C to 58 ∘C for heat source temperatures between 50 ∘C to 80 ∘C. The 3rd model exhibits lower values of maximum temperature lift compared to the reversible models, owing to the inclusion of material properties in its formulation. The performance of the models is demonstrated by determining the maximum temperature lift of four water-based adsorption working pairs, each featuring distinct IUPAC (International Union of Pure and Applied Chemistry) isotherm types. This study will help propel the working pair selection and the thermodynamic modeling of sorption cycles to achieve its near maximum capability.

DOI： 10.1016/j.ijheatmasstransfer.2024.125384

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記述言語：英語   出版者・発行元：九州大学グリーンテクノロジー研究教育センター  

Domestic heat pump is regarded as the most important contributor to greenhouse gas (GHG) emissions from buildings. R410A has been one of the most popular refrigerants in the heat pump system because of its eXcellent thermodynamic performance with near azeotropic nature. HoweVer, R410A greatly impacts climate with its global warming potential (GWP) which is eValuated as 2088 CO2-equiValent. Thus, this research purpose is to inVestigate refrigerant blends with a low GWP to replace R410A in domestic refrigeration applications. A screening of blends is carried out among the list of 5 low-GWP refrigerants, including R451A, R454A, R454C, R455A, and R459B, which are mainly combined by R32, R1234yf, R1234ze(E), and Carbon DioXide. The selection is based on the target GWPs (lower than 300), and the coefficient of performances (COPs) are analyzed on a single-stage heat pump cycle model by Python. The results present that the Volumetric capacities of low-GWP refrigerants are all lower than R410A, but their COPs are higher eXcept for R455A. R454A is considered the most accessible alternatiVe to R410A while its COP is 2% higher than R410A with the largest Volumetric capacity among low-GWP refrigerants. The climate impacts of these low-GWP refrigerants are also studied by the Life Cycle Climate Performance, which shows 22%~25% lower than the emissions of R410A. This research might supply a clue for the deVelopment of these new refrigerants to replace R410A.

DOI： 10.5109/7183465

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CiNii Research

出版者・発行元：Evergreen  

This article preprocesses environmental information and use it as input for the Proximal Policy Optimization (PPO) algorithm. The algorithm is directly trained on a model vehicle in a real environment, allowing it to control the distance between the vehicle and surrounding objects. The training converges after approximately 200 episodes, demonstrating the PPO algorithm's ability to tolerate uncertainty, noise, and interference in a real training environment to some extent. Furthermore, tests of the trained model in different scenarios reveal that even when the input information is processed and does not provide a comprehensive view of the environment, the PPO algorithm can still effectively achieve control objectives and accomplish challenging tasks.

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Energy Advances  

Hydrogen gas is among the sustainable energy forms that counteract the energy crisis. Polymer electrolyte membranes (PEMs) derived from biomass fillers and polyvinyl-based matrix blends have been fabricated and applied in H2 generation through electrolysis. Faradaic efficiencies ranging from 82.8 ± 1.9% to 88.9 ± 1.6% were exhibited when voltages of 6.5 V, 8 V and 10 V were applied; thus, proton conduction and hence H2 generation commenced at 2-2.5 V. The apparent morphology of the PEMs that verified the incorporation of pine bark (PB) and Chinese Tallow Seed Capsule (CT) fillers was visible as surface bumps and internal cavities within the PEMs. Although the proton conductivity of Nafion™ 115's (NF-M) was 23.94 mS cm−1, those of the fabricated PEMs (PB-M, CT-M and SSA-M) were 1.33, 0.46 and 0.48 mS cm−1, respectively. The PB-M exhibited good characteristics, including functional groups and water adsorption; thus, H2 production was achieved, but losses such as bubble production affected efficiency. This study presents a cost-effective alternative for H2 production that can be used in diverse applications.

DOI： 10.1039/d3ya00503h

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出版者・発行元：Journal of Engineering for Sustainable Buildings and Cities  

A comfortable indoor working circumstance can be accomplished by a ventilation and air conditioning system. There are several factors influencing the quality of indoor air, with the insufficiency of ventilation accounting for over 50% of the overall considerations. While traditional air conditioner is able to fulfill the needs of ventilation and indoor temperature control, low-efficiency and high energy consumption no longer align with the current sustainable and energy-efficiency goals. Thus, the development of energy-saving and high-efficiency air conditioning systems is crucial for realizing green and efficient building practices. Evaporative cooling technology, specifically dew-point evaporative cooling, has garnered extensive attention as an efficient cooling method and a candidate for environmentally friendly and high-performance alternatives to traditional air conditioning systems. This article investigates the thermodynamic losses involved in a dew-point evaporative cooling system using the counter-flow design. Detailed mathematical models for the evaporative cooler along with the entropy generation in the channels are developed. The model facilitates calculations of (1) the entropy generation distribution in different layers within the system and (2) the entropy generation of each layer and the whole system under various input conditions. Approaching the system from the second law of thermodynamics perspective, this model serves as a guide for selecting the optimal operating conditions, thus promoting the widespread application and commercialization of dew-point evaporative cooling systems with the counter-flow structure.

DOI： 10.1115/1.4065740

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Energy  

Open adsorption process of gas mixtures involves complex heat and mass transfer mechanisms. Understanding of the physical mechanisms and their impacts on the adsorption process from gas mixtures is vital. In this study, a detailed analysis of an open CO2 adsorption from CO2/N2 mixtures using zeolite 13X-APG was investigated. Key physical mechanisms (unsteady, diffusive, convective, and component source, etc.) involved were scrutinized, and their order of magnitudes relative to the system energy complex were determined. The influences of these physical mechanisms on the equilibrium and dynamic nature throughout the capture were quantified. The validated computational fluid dynamics (CFD) simulations for the same adsorption domain were carried out to verify the rationality of the scaling method. The adsorption time, tad; the maximum average temperature, T‾max; CO2 removal rate, Rre,CO2; equilibrium pressure drop, ΔPeq on different scale parameters and their sensitivity were investigated. The maximum relative sensitivity to porosity was found to be −0.945, 0.0235, −0.357, and −5.33 for tad, T‾max, Rre,CO2 and ΔPeq, respectively. It is observed that heat transfer by the conduction mechanism inside the bed significantly influences all scale parameters, except for ΔPeq. This work will contribute to a better understanding of the atmospheric CO2 adsorption and provide guidance for the design optimization.

DOI： 10.1016/j.energy.2024.130805

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掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Refrigeration  

This study presents a comparative energy, exergy, and life cycle climate performance (LCCP) analysis of various refrigerants in a cascade refrigeration system (CRS). The refrigerants analyzed in the low-temperature cycle (LTC) include R-23, R-116, R-41, R-170, R-1150, and R-1132a whereas high-temperature cycle (HTC) utilizes R-404A, R-455A, R-454C, R-459B, R-161, R-290, R-1270, and R-1234yf. For the first time for CRS, LCCP analysis is conducted and fourth generation low GWP and less flammable prospective refrigerants R-1132a, R-455A, R-454C, R-459B are analyzed. The study aims to find a refrigerant pair that outperforms R-23/R-404A in terms of thermodynamic efficiency while also considering environmental impact and safety considerations. Among the 48 refrigerant groups analyzed, the study reveals that R-170/R-161 and R-41/R-161 demonstrate superior performance in terms of thermodynamic efficiency and environmental impact assessment whereas the largest exergy destruction components are HTC/LTC compressors. However, if flammability is a major concern, the recommended refrigerant pair is R-1132a/R-1234yf, as it is a suitable alternative in terms of safety considerations while still maintaining favorable thermodynamic and environmental performance.

DOI： 10.1016/j.ijrefrig.2023.12.020

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Colloids and Surfaces A: Physicochemical and Engineering Aspects  

Carbon capture, storage, and utilization from post-combustion processes using adsorption phenomena has emerged as a promising solution to the greenhouse gas emission crisis. The capacity of solid porous adsorbents dictates the performance of such carbon capture processes. Developments of porous adsorbents with favourable structural and chemical characteristics of the pore have been a major research area. Computational tools, notably the Grand Canonical Monte Carlo (GCMC) simulation, are widely employed to characterize the adsorption process in crystalline adsorbents like metal-organic frameworks and zeolites. Activated carbons are becoming promising alternatives to conventionally-used zeolite adsorbents for CO2 adsorption, because of their abundant microporosity and cost performance. However, the amorphous nature of the activated carbon materials poses a challenge in accurately modelling their pore characteristics and their adsorption process. Therefore, this study systematically explores the effect of pore size distribution and type of functional groups on the adsorption of CO2 on activated carbons using a simplified slit-pore graphite structure representing the activated carbon adsorbent. Four different pore sizes (7 Å, 8.9 Å, 18.5 Å, and 27.9 Å) and three oxygen-containing functional groups (Carbonyl, Hydroxyl, and Carboxyl) were selected to model the graphite structures. Results from the GCMC simulation reveal a significant rise in the CO2 adsorption capacity (from 4 mmol/g to 21 mmol/g) as the pore size was increased from 7 Å to 27.9 Å. Likewise, the functional groups enhance the low-pressure adsorption process by reducing the onset pressure of the pore filling by a factor of 100, especially in ultra-micropores. Likewise, we demonstrate the increase in the isosteric heat of adsorption due to the reduction in the pore size and the presence of functional groups. Additionally, the study illustrates the adsorbed phase behaviour of CO2 concerning the pore characteristics, a facet often overlooked in the existing literature. The adsorbed phase local density and molecular orientation distribution are analysed to understand the variation in the adsorption uptake and isosteric heat of adsorption properties. The study further identifies the adsorbed phase monolayer to multilayer transition and the ‘T′-shaped orientation of the adsorbed CO2 molecules as the key contributors to the high isosteric heat of adsorption in 8.9 Å pore size. It is envisaged that this study will navigate the precision adsorbent development for an efficient carbon capture process.

DOI： 10.1016/j.colsurfa.2023.133113

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出版者・発行元：International Journal of Energy Production and Management  

The global shift towards renewable energy sources is driven by the desire for a sustainable energy future. Integrating intermittent renewable sources and maintaining grid stability are obstacles that must be overcome to achieve this goal, which is why grid stability and energy storage systems are being investigated in this study using Energy PLAN simulation. This study conducts a thorough analysis of energy storage solutions necessary to support Japan's energy landscape shift to renewable electricity. It offers a comprehensive analysis considering technological, environmental, and policy aspects to evaluate the applicability, difficulties, and potential of renewable electricity. Technical factors emphasize how critical it is to maintain grid balance and consider scalability and technology compatibility with Japan's distinct energy infrastructure. Economic analyses examine revenue streams, levelized storage prices, investment needs, and cost-benefit evaluations to shed light on the viability and appeal of technologies for storing energy from an economic standpoint. The goal of synthesizing these several characteristics is to provide policymakers, and energy stakeholders participating in Japan's ambitious journey towards renewable electricity with strategic insights, practical recommendations, and a roadmap. This study aims to steer Japan's energy landscape towards resilience, sustainability, and diversification by establishing links between imperatives, economic feasibility, and technical breakthroughs.

DOI： 10.18280/ijepm.090105

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掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Heat and Mass Transfer  

In the present study, the adsorption isotherms of difluoromethane (R32) on the activated carbon (MSC 30) throughout a temperature range of 25 °C to 150 °C and pressures up to 3000 kPa are measured for possible application in adsorption cooling systems. The Dubinin-Astakhov model was used to fit the experimental data. A thermodynamic model is proposed in this study to investigate the adsorption potential under supercritical conditions. The model is validated using the isotherm data from the experiments and literatures for different working pairs. The validation results exhibited a good agreement between the proposed model and the experimental data, signifying the precision and dependability of the model. The corresponding adsorption isosteric heat model was derived and verified, taking into account both the inclusion and exclusion of the adsorbed volume correction. Furthermore, the developed models were utilized in the equilibrium analysis of an adsorption heat pump to evaluate the performance of the system in terms of the theoretical coefficient of performance (COP) and specific cooling energy (SCE). The analysis covered the driving heat source temperature ranging from 30 °C to 150 °C, with different evaporation temperatures and adsorption temperatures. The results showed that the maximum COP value of 0.47 for the adsorption heat pump system employing the MSC30+R32 pair was achieved at a desorption temperature of 115 °C, at which the SCE was 315.5 kJ·kg−1. The results can potentially improve the accuracy of predicting adsorption behavior and contribute to the development of more efficient and effective adsorption systems.

DOI： 10.1016/j.ijheatmasstransfer.2023.124873

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Powder Technology  

Activated carbon, due to its notable porosity and cost-effectiveness, emerges as a promising desiccant material. This research delves into the utilization of pinecones as a precursor for the production of activated carbon through steam activation. The resultant activated carbon samples presented a porous structure and exhibited a high water adsorption capacity, with the highest adsorption capacity reaching 0.35 kg/kg, placing it in competition with commercial silica gel. Various experimental parameters were systematically manipulated during the production process to optimize both the pore structure and water adsorption capacity of the activated carbon samples. Elevating the carbonization temperature from 700 °C to 900 °C proved effective in enhancing pore distribution and elevating water adsorption capacity. Furthermore, higher activation temperatures contributed to the formation of additional mesopores and macropores, possibly attributable to micropore enlargement through steam activation. Nevertheless, these elevated activation temperatures resulted in an undesired increment in mesopores concerning water adsorption. The extension of activation time led to increased micropore formation, albeit with concurrent disruption, culminating in heightened total pore volume and surface area. This extension shifted the water adsorption-desorption isotherm to higher relative pressure ranges, accompanied by a larger hysteresis loop. Moreover, an increased steam mass flow rate was found to enhance the pore structure and water adsorption capacity of the activated carbon. The activated carbons exhibited sigmoid-shaped isotherms, signifying their suitability for both open-cycle and closed-cycle adsorption systems.

DOI： 10.1016/j.powtec.2023.119084

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：Applied Thermal Engineering  

Solar energy is an important energy source for a sustainable future. The advancements of solar cells for electricity production require improvements in the cooling technology. Conventional air cooling is not able to cool the photovoltaic (PV) panels effectively. On the other hand, dew-point evaporative cooling (DPEC) can bring down the inlet air temperature below its wet bulb which makes itself an excellent candidate for PV cooling. In this work, a novel cooling configuration that consists of two wet channels: one in the cooler (conventional DPEC) to produce the pre-cooled supply air and the other at the back of the PV panel, was proposed. A physics-based mathematical model utilizing local weather conditions was developed for the system to investigate its transient performance. The cooling performance and subsequent improvement in the PV's energy efficiency of the proposed system were compared with a traditional DPEC-based cooling approach. It was observed that the proposed system can maintain an efficiency of more than 15% (with 16.7% maximum) under two environmental conditions in summer, which is an increase of 16.4% compared to air cooling. The proposed PV cooling method will help to improve the overall performance of the solar PV systems and increase renewable energy utilizations.

DOI： 10.1016/j.applthermaleng.2023.121695

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Applied Engineering Science  

The development of cost-effective and environmentally friendly solar thermal technologies that deliver high performance poses several challenges, where the collector and absorber components play a pivotal role. This research addresses these issues by investigating enhanced temperature generation using a 30 cm × 30 cm Fresnel lens collector under solar illumination from a xenon lamp. Natural stone materials (andesite, coal, and pumice), characterized by granular structures with an average diameter of 1.68–2.00 mm, were selected because of their abundance and eco-friendliness. This research is focused on evaluating the effect of Fresnel lens on temperature generation performance. Two types of temperature generation tests were carried out: wet tests (where the natural stone materials were immersed in distilled water) and dry tests (where the natural stone materials were used in dry conditions). The morphologies of the natural stone materials were examined using an optical microscope and scanning electron microscope. Furthermore, the optical properties of the natural stone materials were analyzed using an ultraviolet–visible (UV–VIS) spectrophotometer. The findings revealed that there were significant improvements in the photothermal absorber performance with the use of a Fresnel lens in dry tests, where the highest temperature was achieved for coal (103.25 °C), followed by andesite (89.00 °C) and pumice (73.00 °C). The impurities varied between the materials, where the impurities were most dominant for pumice while coal was more uniform. Further examination using scanning electron microscope showed that all materials had light-trapping structures in the form of rough surfaces, pores, and crack gaps. Andesite was dominated by rough surfaces, while coal and pumice were dominated by crack gaps and pores, respectively. However, based on the UV–VIS spectrophotometric results, there were no correlations between the optical properties (absorbance, reflectance, and transmittance) and temperature achieved by the photothermal absorber materials. This research demonstrates the potential of using natural stone materials as photothermal absorbers in combination with a Fresnel lens collector for low-to-medium temperature solar thermal applications.

DOI： 10.5937/jaes0-47834

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記述言語：日本語   出版者・発行元：公益社団法人 日本冷凍空調学会  

<p>本研究で吸着材に使用した粉末状活性炭(MSC-30)は，吸着材としてよく使われてきたシリカゲルより比表面積が大きく，さらに大きな吸着量が得られると期待される．吸着質には地球温暖化への影響が非常に小さい低GWP 冷媒のR 1233zd(E)を使用し，その吸着特性を同じ低GWP 冷媒のR 1234yf と比較した．本研究の結果から，単位質量あたりの吸着量および平衡状態に至るまでの吸着速度ともにR 1233zd(E) がより優れた結果を示した．なお，吸着相における体積変化を理論的に考慮したモデルで吸着熱を予測した結果，ほぼ同程度であった．吸着特性に関するこれらの基本情報は，機能性活性炭をフロン類の回収，分離，再生に活用するための基礎情報として高い有効性を有する．</p>

DOI： 10.11322/tjsrae.23-25_oa

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出版者・発行元：Proceedings of the Thermal and Fluids Engineering Summer Conference  

Ultralow-temperature (ULT) refrigeration is essential for various applications, including food, pharmaceutical, and cryogenic processes, where stringent temperature control is required. However, the energy intensity and the use of high-GWP refrigerants in these systems contribute to global warming and climate change. R23 and later R23 mixtures, like R508b, have been considered as zero ozone-depleting potential refrigerants, but their excessive global warming potential has always been a topic of concern. The theoretical replacements are multi-refrigerant multi-cascade cycles which are not efficient or economical enough to be accepted by manufacturers. R1150, R744a and R170 are considered as an environmentally friendly refrigerants to replace R23 family. However, their infra-room critical temperature makes them suitable only in bottoming cycles of cascade systems. This project presents an innovative approach to the single-refrigerant ULT refrigeration cycle. An optimized four-stage flash intercooling turboexpander cycle was designed and thermodynamically analyzed. COP around 0.5 is achievable, even though the cycle has a temperature lift of 140°C and an approximate compression ratio (CR) of 100. Pressure optimization caused the compressors to achieve isentropic efficiency ranging from 0.6 to 0.7, with compression ratios between 2.5 and 4. Different refrigerants and operating conditions were simulated under realistic assumptions and the positive impact of using turboexpanders on performance was confirmed.

DOI： 10.1615/TFEC2024.hpu.050699

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出版者・発行元：Lecture Notes in Mechanical Engineering  

The collector and absorberAbsorber are the two main components most influential in obtaining high solarSolar thermal performance. This study used a 30 × 30 cm Fresnel lens under a xenon lamp to improve the temperature generation performance. The materials photothermal absorbersAbsorber used are coal, andesite, and pumice, with an average granular structure diameter of 1.68–2 mm. This study aims to examine the effect of Fresnel lenses on the temperature generation performance of natural materials with granular as light trap structures and investigate which materials have the best performance. This study used an experimental method with dry and wet conditions in distilled water (H2O). The results show that the use of Fresnel lenses improves temperature generation performance. The best materials sequence in wet conditions are andesite, coal, and pumice. While in dry conditions are coal, andesite, and pumice. The heat generated has the potential to be applied to low and medium-temperature solarSolar thermal technology.

DOI： 10.1007/978-981-97-0106-3_50

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出版者・発行元：AIMS Energy  

The concerns over greenhouse gas emissions, environmental impacts, climate change, and sustainability continue to grow. As a result of countermeasures, many modern gas turbine power plants and combined cycle power plants are considering to use hydrogen as a clean fuel alternative to fossil fuels in the power plant industry. We assessed the implications of such transition from natural gas to hydrogen as fuel in a gas turbine power plant’s balance of plant (BOP) equipment. Using the DWSIM process simulation software and the methodology of compression power changes against different gas compositions, the impact of blending hydrogen with natural gas on temperature differentials, energy consumption, adiabatic efficiency, compression power, and economic implications in gas turbine power plants were examined in this paper. We discovered, through analysis, that there was not a noticeable boost in compression power or energy consumption when 50% hydrogen and 50% natural gas were blended. Similarly, there was no discernible difference in temperature differentials or adiabatic efficiency when 30% hydrogen and 70% natural gas were blended. Moreover, mixing 50% hydrogen and 50% natural gas did not result in a noticeable cost climb. In addition, the techno-economic analysis presented in this paper offered valuable insights for power plant engineers, power generation companies, investors in energy sectors, and policymakers, highlighting the nature of the fuel shift and its implications on the economy and technology.

DOI： 10.3934/energy.2024021

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：E3S Web of Conferences  

Using green biofilters can help eliminate air pollutants and improve urban air quality. In the current study, Prunus × Yedoensis capacity of phytoremediation was investigated as a bio filter of Particulate matter (PM) in spring and summer seasons in Japan. Two samples were analysed to extract three fractions of PM (coarse, fine and ultra-fine). Results showed lower deposition of PM in spring season with total of 20.2 μg.cm-2 and high proportion for fine fraction (2.5-10μm), comparing with summer season which showed a higher deposition of PM with total of 31.9 μg.cm-2. Ultra-fine fraction (0.2–2.5μm) recorded the highest values with a percentage of 23.9% of the total PM deposition. Leaf micromorphological characteristics such as, rough surface and serrated margin can enhance the Prunus × Yedoensis ability of particulate matter accretion. This study confirms that vegetation has an efficient role in improving the quality of urban air. Further structural analysis should be included to deepen the understanding of phytoremediation phenomena in plants.

DOI： 10.1051/e3sconf/202346502030

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：E3S Web of Conferences  

The Power-to-Gas (PTG) is one of the progressing technologies that enables the conversion of electrical energy into hydrogen or methane gas. This study focuses on the comprehensive analysis of energy efficiency, exergy efficiency, and exergy destruction rate within the PTG overall system. The investigation covers the evaluation of the wind turbine for power generation, the proton exchange membrane (PEM) employed in hydrogen production, and the methanation unit dedicated to methane production. The analysis examines the overall system as well as each individual component. By quantifying the energy and exergy efficiencies, this study provides potential improvements for maximizing the PTG system's overall effectiveness. The outcomes of this study contribute to the advancement and deployment of PTG technologies, thereby facilitating the integration of renewable energy sources and promoting sustainable energy solutions.

DOI： 10.1051/e3sconf/202346501011

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掲載種別：研究論文（学術雑誌）   出版者・発行元：International Communications in Heat and Mass Transfer  

The thermogravimetric method was employed to measure the adsorption kinetics of difluoromethane (R32) on MSC30 activated carbon powder adsorbent over a wide range of temperatures (25 °C to 150 °C) and pressures (up to 3000 kPa). The accuracy of various adsorption kinetics models, including FD model, LDF model, semi-infinite model, and modified adsorption kinetics models, were assessed to compare their suitability for predicting the kinetics uptake of the MSC30/R32 working pair. Based on the fitting of the Arrhenius equation, the activation energy Ea and pre-exponential coefficient [Formula presented] were calculated to be 6262.37 (kJ·kg−1) and 0.00853 (s−1), respectively. The MSC30/R32 pair exhibited the highest diffusion time constant and adsorption rate among the common MSC30/refrigerant pairs. Furthermore, a new mass transfer coefficient model was proposed to enhance the accuracy and broaden the range of applicability of the existing model (Jribi model). Comprehensive validations were carried out using various adsorbent-adsorbate pairs over a wide temperature range. The Jribi model in conjunction with the proposed mass transfer coefficient model achieved high accuracy and precision in predicting the adsorption dynamics of diverse working pairs, both during the initial stage and near the saturation state. This study provides valuable insight into the adsorption kinetics analysis, which is essential in accurately simulating adsorption systems for various applications, including refrigeration and air conditioning.

DOI： 10.1016/j.icheatmasstransfer.2023.107148

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Applied Thermal Engineering  

Heat rejection pressure is an important factor influencing the performance of a CO2 (R-744) transcritical vapor compression system. Previous relevant studies have investigated the optimum heat rejection pressure ensuring the maximum coefficient of performance (COP) and operating parameters affecting the optimum pressure value. However, studies presenting quantitatively how much energy can save when an R-744 transcritical system operates in the optimum heat rejection pressure are still rather limited. This work aims to investigate an energy-saving potential gain achieved by managing heat rejection pressure in an R-744 transcritical system and provides quantitatively how much energy can save with that. In that way, this work tries to fill out the research gap. Simulations were carried out employing prevalidated model, the system COP was investigated in various operating conditions, and the optimum heat rejection pressure securing the maximum COP was found. The optimum heat rejection pressure found in this work was compared to the existing correlations, thereby the comparison results are provided in this paper. The system's dynamic performance was also investigated in two different cases: when the expansion valve opening was regulated for the optimum heat rejection pressure, and when the valve opening was adjusted with a thermostatic expansion valve conventionally. In this study, it is observed the given system reduces the compressor power consumption by 62% when the refrigerant temperature at the main gas cooler outlet varies within a range of 33 ℃ to 45 ℃ and the evaporator temperature of 1 ℃. Consequently, in terms of energy-saving potential, this paper highlights the importance of heat rejection pressure management in an R-744 transcritical system and the significance of proper selection for the control target of an expansion valve depending on the system's operating regime.

DOI： 10.1016/j.applthermaleng.2023.121397

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出版者・発行元：Chemical Papers  

In this research, carbon powder produced from bagasse, solid waste of sugarcane production, was used as raw material for creating screen-printed carbon electrode (SPCE), which is named SPAC600. Bagasse was carbonized at 600 °C under N2 flows to produce carbon. The carbonized bagasse was then treated with alkaline solution to leach out the impurities; therefore, the result, AC600, provides a significant increase in surface area from 24.8 to 197.10 m2 g−1. Alkaline treatment also changed the morphology of carbon powder into smaller flakes and removed C–H- aromatic vibration and C–O stretching within Fourier transformed- infrared (FTIR) spectra. The treatment also increases the electric conductivity from 10.01 S/cm to 25.39 S/cm. Alkaline leaching also increases the electrochemical performance of the electrode, proven by the significant increase of anodic current density, Ipa from 5.5 to 12.8 μA, for screen-printed carbon without alkaline leaching (SPC600) and SPAC600, respectively. Furthermore, ferrocene addition to the working electrode (WE) part of the prepared SPCE even increases the electrochemical performance as an analytic electrode, proven by the anodic current density of 173.0 μA. Even though the performance is still lower than a commercial SPCE which provides anodic current density up to 2000 μA, further treatment and modification may enhance the performance of the SPAC600.

DOI： 10.1007/s11696-023-02712-8

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出版者・発行元：AIP Conference Proceedings  

This work investigates a numerical study for titanium dioxide (TiO2) and carbon nanotube (CNT) nanofluid heat transfer performance. Nanofluid flowed in an inner concentric tube with circular, rectangular, and triangular channels were simulated using a mixture model in the Eulerian-Eulerian multiphase approach. The effect of Reynold number on fluid flow and heat transfer characteristic were observed. The results showed an increasing Nusselt number and a decreasing friction factor with an increment in Reynold number. Furthermore, the similar hydraulic diameter in circular, rectangular, and triangular tubes produced different mass flow rates of nanofluid flow inside the inner tube. The different mass flow rates affected their temperature distribution and Nusselt number. These results contribute to our understanding of how nanofluids enhance the heat transfer performance in various tube profiles.

DOI： 10.1063/5.0114128

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Communications in Heat and Mass Transfer  

Adsorption heat transformer (AHT) cycles, unlike adsorption cooling cycles, upgrade the heat source to a higher temperature. Despite the renewed interest in the AHT cycles, its performance enhancement schemes along with their impacts are yet to be explored extensively. Heat and mass recovery schemes on the adsorption cooling/heating cycles have been extensively studied. However, AHT cycles are fundamentally different from those cycles since the AHT cycles employ isothermal-adiabtic processes. Thus, similar impacts of the heat and mass recovery scheme as in the cooling/heating cycles cannot be expected in AHT cycles. Therefore, the impacts and limitations of the internal heat recovery scheme on the AHT cycle are investigated in the current study. The heat recovery scheme aims to minimize the requisite uptake consumption for preheating the adsorber bed by recovering the sensible heat between two adsorber beds having different temperatures. This sensible heat exchange is modeled using modified energy-balance equations to capture the non-linearity of the adsorption process. The preheating uptake loss decreases from 0.014 kg/kg to 0.007 kg/kg at the heat source-heat supply temperature combination of 60 °C–80 °C due to the maximum possible heat recovery in the AHT cycle. As a result of the reduced preheating uptake loss, approximately 5&#37; and 10&#37; increase in the useful heat ratio and exergy efficiency of the AHT cycle, respectively are obtained. This modified AHT cycle further improves the performance ratio of the hybrid AHT-MED (multi-effect distillation) system from 4.6 to 4.9 at the heat source temperature of 58 °C. Furthermore, a parametric analysis of the cycle's performance metrics has been conducted for various degrees of heat recovery, representing the effect of realistic heat exchanger effectiveness during the recovery process. This study will help propel the theoretical development of the adsorption-based thermodynamic systems.

DOI： 10.1016/j.icheatmasstransfer.2023.106774

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記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.5109/6781073

記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

DOI： 10.1299/jsmepes.2023.27.d211

CiNii Research

記述言語：英語   出版者・発行元：The Japan Society of Mechanical Engineers  

<p>This study presents a predictive model utilizing artificial neural networks (ANNs), specifically Multilayer Perceptron (MLP) and Deep Neural Networks (DNN), to forecast the properties of activated carbon under various experimental conditions. The prediction model focuses on the Brunauer-Emmett-Teller (BET) surface area and total pore volume of the activated carbon, with the carbonization temperature, activation temperature, and activation agent as the determining factors. A dataset comprising around 100 samples was used for training the model and testing its accuracy. Results indicate that the DNN model, despite its increased complexity, exhibits superior performance over the MLP model in predicting the properties of activated carbon. The DNN model showed a Mean Absolute Percentage Error (MAPE) of 14.19% for the BET surface area prediction and 17.90% for the total pore volume prediction. The findings underscore the potential of using DNN models in optimizing activated carbon production processes and tailoring its properties for specific applications. Nonetheless, the study suggests the need for expanding the dataset and including more influential factors to further enhance the model's accuracy and reliability.</p>

DOI： 10.1299/jsmepes.2023.27.d212

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Environmental Science and Engineering  

Particulate matter (PM) accumulation on the leaves of two trees and two shrubs were examined for 14 days to study the ability of broad leaves to capture particulate matter in Japan. Two healthy mature leaf samples of each specimen were carefully collected and analyzed through the gravimetric analysis method (four filtration steps). PM in different divisions can be captured and deposited inside the leaf foliage. Fine particles were the highest portion of the PM content captured by the analyzed trees. Leaf features such as hair and wax have been associated with high PM accumulation as presented in Toxicodendron succedaneum (waxy glossy leaves) which was the most effective species among the analyzed species for all PM fraction divisions (PM10, PM 2.5, and PM 0.2), and Prunus × yedoensis (hairy leaves) that captured the largest portion of ultra-fine PM. The surface area has no effect on the accumulation of particulate matter since the Ficus erecta shrub has the largest surface area, but the lowest portions of PM among of the investigated species.

DOI： 10.1007/978-981-99-4101-8_20

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出版者・発行元：Applied Energy  

Adsorption desalination is prescribed as a promising and eco-friendly solution for mitigating water scarcity, owing to its utilization of low-grade thermal waste and zero liquid brine discharge. The keystones that regulate the performance of the adsorption desalination system (ADS) include nature of adsorbents, system design, and operating conditions. The present study aims to provide a state of the art review on the keystones of ADS. Metal-organic frameworks (MOFs) hold remarkable adsorption capacity and tunable structure. However, hydrothermal instability, high cost, and complex synthesizing procedures are the potential challenges that need to be addressed. The technological advancements in ADS have been classified into: (i) Conventional Approach, (ii) Heat and Mass Recovery Approaches, (iii) Hybridization Approaches, (iv) and Adsorbent Substituting Approach. The study provides critical insight and compares the performance of each approach based on specific daily water production (SDWP), specific cooling power (SCP), and coefficient of performance (COP). The conventional ADS produce SDWP of 4.7 m3/ton/d, however producing zero and/or minimal SCP while using payable energy of 1.50 kWh/m3. In heat/mass recovery approaches, pressure equalization-valve delay schemes and master–slave configuration provide ∼ 5 % additional water adsorption/desorption on/from silica-gel and reduce ∼ 50 % thermal heating load, respectively. Evaporator-condenser amalgamation emphasizes the evaporator temperature of 30–42 °C leading towards ∼ 69 % higher SDWP with zero SCP. Dual stage, multi evaporators/condensers scheme is found supportive in cogenerating feature of ADS thereby improvising COP to ∼ 0.87. In hybridization approach, ejector integrated ADS produces SDWP of 80 m3/ton and COP of 2.22 using payable energy of 0.92 kWh/m3, however, needs experimental validation. In the adsorbent substituting approach, CPO-27(Ni), Emim-Ac/Syloid 72FP, and composite adsorbent manifest the SDWP to higher levels. The operating conditions are sensitive and need to optimize depending on the configuration of ADS. Possible future research directions may include efficient designing/ sizing of evaporators/ condensers, minimizing the heat and mass transfer resistances in adsorber/desorber reactor, optimize the thickness of the adsorbent layer in heat exchangers, and investigating wide range of adsorbent classes that can be driven with very low regeneration temperature.

DOI： 10.1016/j.apenergy.2022.120101

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Air-Conditioning and Refrigeration  

Thermally driven desiccant- and evaporative cooling-based technologies are promising greener and cheaper alternatives to compressor-based systems due to the separate handling of latent and sensible loads. Desiccant air-conditioning (DAC) systems comprise a desiccant dehumidifier, a sensible cooling unit, a heat source for regeneration, and a heat recovery unit. These components of a DAC system can be arranged in various ways to give different configurations with varying advantages and disadvantages. In this study, five configurations of thermally driven desiccant dehumidifier- and dew point evaporative cooling (DPEC)-based DAC systems were investigated. Seven evaluation criteria namely regeneration temperature, desiccant moisture removal capacity, COPt, DPEC L/H, heat exchanger UA, system size, and fan power requirement were employed. Results show that the standard cycle in ventilation mode offers the highest COPt despite having the highest regeneration temperature. Recirculation of the return room air can operate at a significantly lower regeneration temperature at the expense of larger equipment size and much lower COPt. DAC with an internally cooled dehumidification can operate at low regeneration temperature at the expense of higher fan power and slightly lower COPt. Dividing the dehumidification process into two stages can offer operation at moderately lower regeneration temperature without severely affecting the other criteria. This study can serve as a guide for the selection of an appropriate DAC configuration for space cooling depending on the objective criteria and the resources available.

DOI： 10.1007/s44189-022-00011-7

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：九州大学大学院総合理工学府  

Dew point evaporative cooling (DPEC), a type of indirect evaporative cooling where a single stream of air flows sequentially through the dry and wet channels, can cool air theoretically to its dew point temperature. In this study, the effects of design parameters, operating parameters, and inlet air condition to the cooling performance of a counter-flow DPEC was investigated. It has been shown that for the nominal condition of channel length = 1m, channel height = 5mm, inlet air velocity = 1.5 m/s, and working air ratio = 0.3, the inlet air with temperature of 30o C and humidity of 0.010 kg/kg da was cooled to 19.3oC which is lower that its wet bulb temperature of 19.6oC. The temperature can be cooled further by increasing the channel length, decreasing the channel height, decreasing the inlet air velocity, or increasing the working air ratio.

DOI： 10.5109/5909100

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：九州大学大学院総合理工学府  

Nuclear energy has been considered as clean and environmentally friendly method of power production. With the emergence of Generation IV reactor, a new horizon was opened in nuclear technology. The invention of new materials and production processes and magnetic bearings, the new ideas for increasing the efficiency of nuclear power plants are being considered more feasible. In this paper the thermodynamic analysis of a Helium pseudo-isothermal expansion and compression power cycle which can be utilized to couple with a Very High-temperature Gas Reactor (VHTR) was performed. A novel thermodynamic modelling of estimating the isothermal process based on the irreversibility during the compression or expansion was done. The results show that isothermal process is not so far from the reality and the power cycle can exceed other designs in terms of efficiency.

DOI： 10.5109/5909105

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記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/app122010630

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出版者・発行元：Heat Transfer Engineering  

Heat and mass transfer characteristics (HMTCs), which defined the latent and sensible load, are essential for developing an effective desiccant dehumidification system (DSDHS). Therefore, the current work provides an investigation on the HMTCs, in the form of the Nusselt and Sherwood numbers. Under constant adsorption temperature of 293 K, the HMTCs were analyzed with three different regeneration temperatures of 308 K, 318 K, and 328 K. While the velocities were kept constant of 0.1 kg/s both for adsorption and regeneration processes. The DSDHS used the polymer material having the highest adsorption capacity of 0.78 kg/kg. Using the thermal and mass resistance approaches, the heat, and mass transfer coefficients were able to predict. The results show that the highest regeneration temperature revealed the most top differences between the humidity ratio inlet and outlet, which was 2.2 g/kg. The Nusselt number values, as well as Sherwood number, tend to increase with the rise of regeneration temperature. The proposed empirical correlation for predicting the HMTCs was followed by the experimental data with a maximum discrepancy of 17%. It is suggested that the properties of the interface must be carefully acquired to reduce the discrepancy between the experimental data and analytical.

DOI： 10.1080/01457632.2021.2000582

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：Sustainable Energy Technologies and Assessments  

Humidification-dehumidification desalination (HDD) systems offer a feasible approach for the production of fresh water in inaccessible areas as they can be operational using renewable energy and require little maintenance. Various studies are being carried out to boost the system performance. In this paper, an open air open water HDD system is proposed that exploits the enhanced evaporation and condensation processes by implementing with the Maisotsenko cycle (M-cycle). The system utilizes solar energy as the energy input to heat the saline water. A thermodynamic model is formulated under steady-state conditions, considering the first and second law of thermodynamics. The energetic and exergetic performance of the system is studied. The model is first validated with the experimental data and a good agreement is found where the maximum discrepancy is about 6.0 &#37;. Effects of different operating conditions on key performance parameters such as the Gain Output Ratio (GOR), specific energy consumption (SEC), exergy destruction, and exergy efficiency are analyzed. An improvement is observed in the GOR when the inlet air temperature is raised at constant humidity ratio. The system exhibits better performance in dry air environment when compared with humid air environment. The analysis shows a maximum mass flow rate of desalinated water of 22.3 kg/h, recovery ratio (RR) of 0.223, GOR of 3, SEC of 0.23 kWh/kg and an exergy efficiency of 43.21 &#37;.

DOI： 10.1016/j.seta.2022.102141

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Ambient Energy  

Simulation-based assessment is performed here by using the single-phase model (S-PM) and the two-phase mixture model (T-PMM). The models are used to investigate the heat transfer performance of TiO2/water nanofluids inside a circular tube with a diameter of 1.09 mm and a length of 306 mm. Reynolds numbers are varied from 600 to 2100, while the nano-particle concentration is 1.0, 2.0, 3.5 and 5.0 vol.&#37;. Higher friction factor (f) and convective heat transfer coefficient (h) were observed for titania-based nanofluids compared to those of the base fluid (water). Heat transfer performance of the nanofluid increases as the nanoparticle concentration is increased. Likewise, the augmentation in pressure drop increases with nano-particle concentration. The highest enhancement in the Nusselt number of 14.81&#37; was observed for nanoparticles with a concentration of 5 vol.&#37; at the Reynolds number of about 1500.

DOI： 10.1080/01430750.2022.2085797

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：Energy  

Recovery of the low-temperature waste heat for electricity generation has been gaining a significant interest. An Inverted Brayton Cycle (IBC) is often employed to convert the low-temperature waste-heat to electricity while the thermal efficiency and specific work output are poor. In this paper, a new energy recovery scheme is introduced incorporating the IBC with a Regenerative Heat and Mass Exchanger (RHME). The RHME is a heat and mass exchanger that consolidates a recuperator (for thermal efficiency improvement) and an Indirect Evaporative Cooler (for enhanced specific work). Numerical models for RHME and the IBC were judiciously developed where possible condensation in the product air channel was accounted for. The model was validated with the experimental data and the cycle was investigated for various waste-heat sources (50–150 °C). When compared to a conventional air-cooling IBC system, incorporating the current energy recovery scheme increases the thermal efficiency from 8.13&#37; to 14.36&#37; and specific work output from 10.38 to 12.46 kJ/kg equivalent to 76.63&#37; and 20.1&#37; improvements, respectively. The unprecedented performance improvement is realised from the exploitation of the regenerative and air-saturation (cooling) mechanisms for both energy recovery and cooling of the working fluid.

DOI： 10.1016/j.energy.2022.123726

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Thermal Analysis and Calorimetry  

The desiccant dehumidification system can separate the latent heat and sensible heat in the air-conditioning system and achieve energy savings by removing latent heat. Industrial waste heat and renewable energy could be utilized in desiccant dehumidification systems, where the desorption process can be performed below 70 °C. The vapor pressure and temperature of the regenerating air dictate the desorption process corresponding to the isotherm properties. This study has focused on the effects of various temperatures and humidity ratios of regeneration air on the performance of a desiccant dehumidifier using a polymer as an adsorbent. Experiments were performed using the regeneration air with the humidity ratios of 0.005 kg kg−1, 0.010 kg kg−1, 0.015 kg kg−1, and 0.020 kg kg−1, while the air temperatures were varied from 40 °C to 70 °C. The evaluation of this study employs the adsorption/desorption amount, average moisture removal capacity, and latent energy ratio (LER) of the regeneration process as key performance indexes. At the regeneration temperature of 68 °C, the peak desorption amount at the humidity ratio of 0.005 kg kg−1 and 0.010 kg kg−1 both reached 0.011 kg kg−1. The results indicated that the higher desorption temperature led to a higher desorption amount. Besides, with the increased desorption temperature, the average moisture removal capacity increases. In contrast, the high humidity ratio of regeneration air resulted in a weak dehumidification ability. Lower regeneration temperature was difficult to apply to regenerate the polymer-based desiccant under a high-humidity-ratio atmosphere. To attain a high LER, a lower humidity ratio of dry air and regeneration temperature was preferred. The regeneration air with a humidity ratio of 0.020 kg kg−1 is not suitable to apply in the dehumidification system in the temperature range of 40–70 °C.

DOI： 10.1007/s10973-022-11368-7

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Thermal Analysis and Calorimetry  

Adsorption heat transformers (AHTs) are considered as promising systems for upgrading waste heat to a higher temperature. The cycle operates among three temperature reservoirs: (i) heat sink at the low temperature (TL), (ii) heat source at the medium temperature (TM), and (iii) heat supply at the high temperature (TH). In the present study, the performance the AHT cycle was analyzed for possible applications in the waste heat upgrade and thermal desalination. An equilibrium model was developed using adsorption characteristics and isotherm data. Five types of commercially available silica gels and three types of zeolites were investigated as adsorbents. Nonlinear optimization technique was utilized for the determination of the intermediate pressure and uptake for preheating and precooling phase of the AHT cycle. The performance parameters in terms of useful heat ratio and condensation heat ratio were determined and compared for the reservoir temperatures at 30 °C (TL)—60 °C (TM)—80 °C (TH). Parametric evaluation of the performance parameters was carried out based on the variation in gross temperature lift, as well as the heat exchanger mass ratio. It was found out that reduction in the gross temperature lift had a positive impact on the useful heat ratio and a negative influence on the condensation heat ratio of the AHT cycle. Significant variations in the maximum adsorption capacity and slope of the isosteric heat of adsorption across various adsorption pairs containing zeolites were observed. As a result, AQSOA-Z01 zeolite exhibited the highest heat exchange values of the AHT cycle in the range of ~ 320–370 kJ per kg of adsorbent. On the contrary, type AQSOA-Z02 zeolite displayed the lowest corresponding values in the range of ~ 60–90 kJ kg-1 of adsorbent. On the other hand, variation across the different silica gel adsorbents was comparatively smaller because of similar isotherm and isosteric heat of adsorption characteristics. This study will assist the research on the theoretical development of the AHT cycle via material selection and system design optimization.

DOI： 10.1007/s10973-022-11350-3

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記述言語：英語   出版者・発行元：Japan Society of Refrigerating and Air Conditioning Engineers  

<p>With the increase in energy consumption, energy-saving attracts lots of attention. The desiccant dehumidification system is a potential substitute for the air-conditioning system that can achieve energy saving by decreasing the energy input for latent heat. Besides, the desiccant dehumidification system can further utilize the low-temperature heat waste in the desorption process. Thus, this study has focused on the low temperatures range between 40ºC and 70ºC on the desorption process with low humidity ratios of dry air as 0.005 kg/kg. The results indicate that, with the increasing desorption temperature, the water removal amount also increases, which means the ability of dry air to capture moisture from desiccant increases with higher temperature. At the desorption temperature of 68ºC, the average moisture removal capacity reached the peak, 0.0081kg/kg. Conversely, the coefficient of performance (COP) of the desorption process presented a downward trend with increasing desorption temperature. At desorption temperature 41ºC the COP is highest at almost 0.8, then gradually dropped to around 0.51 at desorption temperature 68ºC. The optimal desorption temperature can be determined as 54ºC.</p>

DOI： 10.11322/tjsrae.21-40de_em_oa

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記述言語：英語   出版者・発行元：Japan Society of Refrigerating and Air Conditioning Engineers  

<p>Nanotailored microporous silica represents one of the more recent artificially prepared advanced materials used in heat transformation and conservation field after silica gel and various zeolite and zeolite-like materials. In this work, we introduce experimental findings on the energy characteristics of water adsorption on nanotailored microporous silica with 1.5 % aluminium doping in the structure. The downscaled system in this work simulates actual working conditions in a controlled environment for both heating and cooling mode. The key properties of this material lie in the regeneration temperatures 60 to 80 ℃ and COP, which reaches values around 0.6 in case of cooling and 0.7 in case of heating. In absolute values at Δ<i>T</i> = 15 ℃, the system reaches storing capacities of about 90 Wh and 126 Wh per adsorbent kilogram in terms of cooling and heating potential energy, respectively. An important factor of kinetic influence on system performance is discussed on a basis of constant time experiment and time-dependent energy flow breakthrough analysis. Constraining factors are found to be in parallel through the driving force of the pressure swing as well as the heat transfer through the body of the adsorption bed.</p>

DOI： 10.11322/tjsrae.21-37de_em_oa

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記述言語：英語   出版者・発行元：Japan Society of Refrigerating and Air Conditioning Engineers  

<p>Water vapor adsorption on activated carbon (AC) for dehumidification purposes has gained much attention due to the abundance of benefits provided by AC. The working region limited in high water vapor relative pressure (<i>P/P0</i>) makes this material suitable only for removing water vapor at a highly humid region. In this study, ozone oxidation was conducted to introduce more oxygen-based functional groups on AC to attract more water molecules. Based on surface characterization results, ozone oxidation increases oxygen functional groups such as carboxylic on AC but decreases their pores. The more AC exposed to ozone, the more different properties could be observed. The increment of functional groups enhances the water vapor adsorption uptake at <i>P/P0</i> ≤ 0.6, shifting the water sorption into lower <i>P/P0</i>.</p>

DOI： 10.11322/tjsrae.21-36de_em_oa

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Refrigeration  

R1132(E) (trans-1,2-difluoroethylene, C2H2F2) is a potential next generation refrigerant to be utilized in air conditioning applications. This hydrofluoroolefin (HFO) refrigerant possesses an extremely low-GWP value below 1 and it is an excellent candidate for replacing R32 in blends such as R410A, which are subjected to local and international greenhouse gas regulations for limiting global warming. Two isochoric apparatus were used to measure the saturation pressures of R1132(E) from 240 K to its critical temperature. At the critical temperature, the critical pressure of R1132(E) was also directly measured. Twenty-four saturation pressures including the critical point were used for optimizing a Wagner-type equation representing the saturation pressure curve. The absolute average deviation of the saturation pressures of R1132(E) predicted by the model using the fitted parameters and the experimental data is 0.02&#37;. The optimized Wagner-type equation of saturation pressures is used for determining the acentric factor of R1132(E) as 0.2433, which is further utilized for the prediction of the saturation pressures using the Peng-Robinson cubic equation of state within an absolute average deviation of 0.31&#37;.

DOI： 10.1016/j.ijrefrig.2021.12.014

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人日本機械学会・社団法人日本伝熱学会  

Renewable energy-based microgrid systems are widely being studied as electrification methods for rural communities in developing countries. Waste heat generated by the components of the microgrid systems, such as the biogas driven generators (BDG), presents the potential of utilizing the low-grade heat in a way that can contribute to the sustainability of such energy systems. From the points of view of affordability, local manufacturability, and applicability for agriculture, thermally driven pumps (TDP) may be attractive for coupling with such microgrid systems. Therefore, the current study has focused on the development of a new type of thermally driven pumping system as a potential waste heat utilization component for microgrid applications in rural areas. A liquid piston-type TDP concept without moving parts, except few valves, was developed and parametric experimental investigations were carried out. The performance and characteristics of the system were studied, which revealed that the proposed system has a superior performance compared to the literature. It was also found that the system performance strongly depends on the heat addition rate and delivery capacity of the system, which are suitable characteristics for the intended application. Hence, the experimental data were used to estimate whether the proposed system can pump enough water that needs to be supplied for the biogas production to supply a 10 kW BDG unit of a microgrid. It was found that 87 – 93&#37; of the total pumped water (13 – 27 m3) would be available for agricultural and other purposes while only 6 – 13&#37; would need to be fed to the biogas digester. Generally, the results seem to be promising, and yet there are potentials for the optimization and improvement of the proposed system, hence they have been pointed out.

DOI： 10.1299/jtst.21-00323

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：Applied Energy  

Multi-effect distillation (MED) systems are considered to be the most energy-efficient thermal desalination methods. This paper introduces the development of a novel thermal desalination system for performance superior to MED systems for the same operating temperature limits. Such an unprecedented achievement was attained by upgrading the heat source using the chemical potential of adsorption phenomena. The proposed Adsorption Heat Transformer (AHT) cycle hybridized with Multi-effect distillation system (AHT-MED) exhibits higher performance ratio and water production rate than a conventional MED system for the same heating source and sink. The heat generated by the heat of adsorption with the temperature higher than the heat source is supplied to the first effect of the MED system, thus, extending the temperature difference between the Top Brine Temperature (TBT) and Bottom Brine Temperature (BBT). The higher temperature difference offers more number of effects, with the equivalent temperature difference between the effects (ΔTe) as the design parameter. Using the low-temperature heat source (as low as 58 °C), the system can employ an increased number of effects (as high as 11) due to the supply of heat at an increased temperature of around 80 °C. The proposed system achieves a higher performance ratio (approximately 5.4) and water production rate (2 kg/s) compared to the standalone MED system (PR: 4.2, WPR: 1 kg/s) with the number of effects of the hybrid system as 10 at constant interstage temperature difference between the standalone and hybrid systems. This novel AHT-MED system opens up new possibilities for low-temperature heat source-driven thermal desalination with significantly improved performance.

DOI： 10.1016/j.apenergy.2021.117744

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記述言語：その他   掲載種別：論文集(書籍)内論文   出版者・発行元：Green Energy and Technology  

The poultry industry is a major contributor to worldwide food production. Poultry birds are fatally sensitive to humidity and temperature. Therefore, a temperature/humidity control system is principally required for optimum growth of the birds. Conventionally, to regulate temperature/humidity in control sheds, vapor compression air-conditioning systems are used which are not only costly but also consume an enormous amount of primary energy. Alternatively, evaporative cooling pads are also used which increase humidity level inside control sheds results in various fungal diseases. In this regard, this study explores desiccant air-conditioning (DAC) options for climatic conditions of Multan (Pakistan). These systems are operated with thermal energy that could be available via low-grade waste heat and renewable energy options. Such systems would allow the development of poultry houses in off-grid remote areas which eventually support the green smart grid’s philosophy. Two DAC options are studied which are involved in standalone DAC and evaporative cooling (EC) assisted DAC concepts. Psychrometric and thermodynamic analysis with two types of desiccant materials is used in the study (i.e., silica-gel and hydrophilic polymeric-sorbent). The study determined body-weight-gain, feed-conversion-ratio, sensible/latent heat, and temperature-humidity-index of birds. As such, the performance of the proposed systems is investigated for cooling capacity and COP. According to results, the EC-assisted polymeric-sorbent system has resulted feasible in terms of maximum cooling capacity and COP. This system could achieve thermal comfort of birds at THI of less than 30 °C.

DOI： 10.1007/978-3-030-90720-4_16

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

DOI： 10.1299/jsmepes.2022.26.e134

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記述言語：英語   出版者・発行元：The Japan Society of Mechanical Engineers  

<p>Dew-point evaporative cooling is an air conditioning technology which has possibility of achieving lower temperature, higher efficiency, lower water consumption. Understanding the heat and mass transfer principles of the system is crucial for the applications. This study presents a mathematical model which is conducted to (1) study the heat and mass transfer processes under different initial condition; (2) analyze the factors affecting the performance of system. And an experimental setup has been adopted to give a validation for the numerical model</p>

DOI： 10.1299/jsmeenv.2022.32.1402-07-06

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：International Exchange and Innovation Conference on Engineering and Sciences  

In order to utilize the adsorption chiller or heat pump as a next-generation air conditioning system, several issues still remain, such as performance improvement, miniaturization, and cost reduction. It is known that the activated carbon-freon refrigerant pair has a relatively lower coefficient of performance (COP) than the silica gel-water or freon refrigerant pair and zeolite-water pair. However, there is a possibility to contribute minimize the adsorption heat pump system utilizing Freon refrigerant since it works in high-pressure regions and has a high saturation vapor density. Therefore, evaluating and improving the performance of Freon refrigerant is an important future task.

DOI： 10.5109/5909083

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記述言語：その他  

DOI： 10.1007/978-3-030-86394-4_5

記述言語：その他  

DOI： 10.1007/978-3-030-86394-4_2

記述言語：その他  

Fresh fruits and vegetables are perishable and possess short life under ambient conditions. Post-harvest losses are one of the major concerns in the storage of fruits and vegetables. In this regard, proper control of temperature and humidity is required to reduce post-harvest losses and enhance the shelf life of fruit and vegetables with the finest quality, quantity, and nutritive attributes. Several options such as vapor compression-based air-conditioning systems have been studied and implemented worldwide for possible storage of fruits and vegetables but consume a huge amount of energy and degrading the environment. Therefore, in this study, the energy-efficient standalone desiccant air conditioning (DAC) and Maisotsenko cycle-based desiccant air conditioning (M-DAC) systems were explored from the viewpoint of potential storage of fruits and vegetables. The systems analysis to check the feasibility was carried out in the climatic conditions of Multan, Pakistan. The proposed systems were thermodynamically explored from the viewpoint of ideal temperature and humidity control storage zones, cooling capacity, and coefficient of performance (COP). The results appreciably showed that the M-DAC system performed relatively better than the proposed standalone DAC system. It was found that the cooling capacity and COP of the M-DAC system were found 32.5 kJ/kg and 1.07, respectively, as compared with standalone DAC.

DOI： 10.1007/978-3-030-86394-4_4

記述言語：その他  

DOI： 10.1007/978-3-030-86394-4_3

記述言語：その他  

DOI： 10.1007/978-3-030-86394-4_6

記述言語：その他  

DOI： 10.1007/978-3-030-86394-4_1

記述言語：その他   掲載種別：研究論文（学術雑誌）  

Indoor air humidity plays a vital role in determining occupants’ health and industrial product quality. Removing excess humidity by adsorption dehumidification is still facing a challenge in finding a suitable material with high adsorption capacity and low regeneration temperature. In this study, the theoretical dehumidification capacity of prepared acorn nutshell-based activated carbons was calculated and compared with silica gel type RD and RD-2060. The calculation was based on the outdoor air condition in two Asian capital cities: Jakarta and Tokyo. The theoretical study found that prepared activated carbon has better dehumidification performance under Jakarta conditions using regeneration temperatures of less than 60°C. Under Tokyo conditions, activated carbon shows auspicious performance during the summer season. Compared with silica gels, acorn nutshell-based activated carbon has a better dehumidification capacity to process high humidity ambient air with a lower regeneration temperature.

DOI： 10.1016/j.ijrefrig.2021.08.012

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.icheatmasstransfer.2021.105594

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.egyr.2021.09.003

記述言語：英語  

DOI： 10.18462/iir.HFO.2021.1023

記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Sustainable Energy  

This paper presents a comparative analysis of the potential working fluids for a promising thermodynamic cycle (Thermal Power Pump cycle) for the utilisation of low-grade heat. The cycle was analyzed along with nucleate boiling correlations and film condensation analysis for variable heat source temperatures (50–150°C) using nine potential working fluids. The working fluids showed varying degrees of cycle performance and system size requirements. Among the working fluids, cyclopentane seems to be an attractive choice of working fluid, due to its superior cycle performance over the wide range of heat source temperatures with moderate system size requirements. For temperatures above 146°C and below 60°C, water and n-pentane are selected, respectively. Working fluids with stronger molecular forces seem to approach the properties of an ideal working fluid for better performance of the system.

DOI： 10.1080/14786451.2021.1924717

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記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2021.116825

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2020.116531

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.5109/4372281

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.5109/4372280

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2020.12.005

記述言語：その他   掲載種別：研究論文（学術雑誌）  

記述言語：その他   掲載種別：研究論文（学術雑誌）  

In this study, we evaluated the performance of low Global Warming Potential (GWP) refrigerant R1234yf on the activated carbon (MSC‐30) for adsorption heating applications. The ad-sorption isotherms of MSC‐30/R1234yf were measured using a constant‐volume–variable‐pressure (CVVP) method from very low relative pressure to the practical operating ranges. The data were fitted with several isotherm models using non‐linear curve fitting. An improved equilibrium model was employed to investigate the influence of dead thermal masses, i.e., the heat exchanger assembly and the non‐adsorbing part of the adsorbent. The model employed the model for the isosteric heat of adsorption where the adsorbed phase volume was accounted for. The performance of the heat pump was compared with MSC‐30/R134a pair using the data from the literature. The analysis cov-ered the desorption temperature ranging from 60 °C to 90 °C, with the evaporation temperature at 5 °C and the adsorption temperature and condensation temperature set to 30 °C. It was observed that the adsorption isotherms of R1234yf on MSC‐30 were relatively lower than those of R134a by approximately 12&#37;. The coefficient of performance (COP) of the selected pair was found to vary from 0.03 to 0.35 depending on the heat source temperature. We demonstrated that due to lower latent heat, MSC‐30/R1234yf pair exhibits slightly lower cycle performance compared to the MSC‐ 30/R134a pair. However, the widespread adaptation of environmentally friendly R1234yf in auto-mobile heat pump systems may call for the implementation of adsorption systems such as the direct hybridization using a single refrigerant. The isotherm and performance data presented in this work will be essential for such applications.

DOI： 10.3390/app11052279

記述言語：その他   掲載種別：研究論文（学術雑誌）  

Poultry are one of the most vulnerable species of its kind once the temperature‐humidity nexus is explored. This is so because the broilers lack sweat glands as compared to humans and undergo panting process to mitigate their latent heat (moisture produced in the body) in the air. As a result, moisture production inside poultry house needs to be maintained to avoid any serious health and welfare complications. Several strategies such as compressor‐based air‐conditioning systems have been implemented worldwide to attenuate the heat stress in poultry, but these are not economical. Therefore, this study focuses on the development of low‐cost and environmentally friendly improved evaporative cooling systems (DEC, IEC, MEC) from the viewpoint of heat stress in poultry houses. Thermodynamic analysis of these systems was carried out for the climatic conditions of Multan, Pakistan. The results appreciably controlled the environmental conditions which showed that for the months of April, May, and June, the decrease in temperature by direct evapo-rative cooling (DEC), indirect evaporative cooling (IEC), and Maisotsenko‐Cycle evaporative cooling (MEC) systems is 7–10 °C, 5–6.5 °C, and 9.5–12 °C, respectively. In case of July, August, and September, the decrease in temperature by DEC, IEC, and MEC systems is 5.5–7 °C, 3.5–4.5 °C, and 7–7.5 °C, respectively. In addition, drop in temperature‐humidity index (THI) values by DEC, IEC, and MEC is 3.5–9 °C, 3–7 °C, and 5.5–10 °C, respectively for all months. Optimum temperature and relative humidity conditions are determined for poultry birds and thereby, systems’ performance is thermodynamically evaluated for poultry farms from the viewpoint of THI, temperature‐humid-ity‐velocity index (THVI), and thermal exposure time (ET). From the analysis, it is concluded that MEC system performed relatively better than others due to its ability of dew‐point cooling and achieved THI threshold limit with reasonable temperature and humidity indexes.

DOI： 10.3390/su13052836

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.5109/4372284

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.5109/4372285

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.5109/4372279

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/app11020678

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2020.09.020

記述言語：その他   掲載種別：研究論文（学術雑誌）  

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2020.115952

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2020.116104

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2020.10.009

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.egyr.2020.11.038

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/su122410582

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.powtec.2020.08.020

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.powtec.2020.08.020

記述言語：その他   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1007/978-3-030-52071-7_26

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/en13164247

記述言語：その他   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/01457632.2020.1776997

記述言語：その他   掲載種別：研究論文（学術雑誌）  

記述言語：その他   掲載種別：研究論文（学術雑誌）  

The urge to replace hydrofluorocarbons which possess high global warming potentials has taken center stage in the air conditioning industry due to both international and local policies such as the Kigali Amendment and Japan’s revised Fluorinated Gas law. This has prompted the exploration of novel refrigerants as well as their mixtures to create high performance environmentally friendly alternatives. These refrigerants can be integrated into existing systems as ‘drop in’ refrigerants, which provide a simpler and low cost substitution process to replace environmentally harmful refrigerants such as R410a. R410a is currently a widely used refrigerant in air conditioning systems, but is to be phased out of use under the Kigali Amendment by the late 2040s. Thus to compare the suitability of replacing this refrigerant with environmentally friendly ‘drop in’ alternatives, a preliminary baseline investigation on a mechanical vapor compression chiller with R410a is conducted via performance and exergy indicators. The testing procedure utilized Air Conditioning, Heating and Refrigeration Standard 551/591 which revealed an optimum charge amount of 0.70 kg with a peak performance near 88&#37; of full capacity. The heat exchanger overall heat transfer coefficients showed varying trends, whilst the exergy destruction was as expected highest for the compressor.

DOI： 10.1080/01457632.2020.1776990

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijthermalsci.2020.106261

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2020.115029

記述言語：英語  

DOI： 10.1016/j.rser.2019.109630

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/app10030868

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.micromeso.2019.109644

記述言語：英語  

記述言語：その他   掲載種別：研究論文（学術雑誌）  

The performance of an adsorption system using Maxsorb III + ethanol pair is investigated for practical heat pump applications. An adsorption system using a single bed with a single evaporator/condenser is employed and the performance of the system is assessed for various regeneration temperatures (80 °C, 70 °C and 60 °C). The impact of the adsorption time on the performance of the selected pair is further evaluated. The potential application of the present adsorbent + adsorbate pair is the automobile air-conditioning system where the exhaust waste heat will be recovered to operate the adsorption system. Thus, antifreeze fluid is employed as the heat transfer medium for the adsorber and the evaporator/condenser heat exchanger. A mathematical model is developed to estimate the uptake amount from the experimental data. The sensible heat change (thermal mass), the superheating of the refrigerant in the adsorber, the adsorber heat leak and the heat rejection to the heat transfer medium are accounted for. The uptake amount is further verified using the classical p–T–q diagram. For operation using 30 °C adsorber coolant inlet and 15 °C chilled water inlet, the cooling capacity of the present system ranges from 15 to 35 W for the adsorption times of 600 s and 300 s, respectively. It is observed that the regeneration temperature significantly influences the net uptake of the system. The maximum net uptake is recorded to be about 0.995 kg/kg for the regeneration temperature of 80 °C. The system is further assessed using the ratio of the cooling capacity to the adsorption heat.

DOI： 10.1016/j.ijrefrig.2018.06.009

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/en12163041

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10450-019-00107-4

記述言語：英語  

DOI： 10.3390/app9112385

記述言語：その他   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1063/1.5098218

記述言語：英語  

DOI： 10.1016/j.applthermaleng.2018.12.144

記述言語：英語  

DOI： 10.1177/0143624419893660

記述言語：英語  

DOI： 10.1177/0957650919869503

記述言語：英語  

DOI： 10.1515/ijfe-2019-0063

記述言語：英語  

DOI： 10.25165/j.ijabe.20191201.3854

記述言語：英語  

DOI： 10.1016/j.ijheatmasstransfer.2018.07.097

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.jced.8b00403

記述言語：英語  

DOI： 10.1016/j.ijthermalsci.2018.08.025

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2018.09.009

記述言語：英語  

DOI： 10.1016/j.applthermaleng.2018.08.066

記述言語：その他  

After publishing our articles on the studies of the vapor–liquid phase distribution in a header type evaporator consisting of upward [refer to Wijayanta et al., 2016] and downward [refer to Wijayanta et al., 2017] minichannel-branching conduits, we were motivated to extend the work to the heating load acting on the branches because till date, it is believed to cause maldistribution. Refrigerant R134a experiments with heating loads from 50 to 300 W on the branches were performed. The vapor quality in the test section inlet was maintained between approximately 0.1 and 0.4. Although a larger phase separation occurred in the header at the maximum heating load of 300 W at a vapor quality in the test section inlet of 0.41, it was notable that the geometry configuration had a stronger effect on the phase distribution.

DOI： 10.1016/j.ijrefrig.2018.08.003

記述言語：英語  

DOI： 10.3390/app8112061

記述言語：英語  

DOI： 10.1007/978-3-319-26695-4_22

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.renene.2018.01.045

記述言語：英語  

DOI： 10.3390/en11061499

記述言語：英語  

DOI： 10.5109/1936220

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/en11061584

記述言語：英語  

DOI： 10.5109/1936212

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/app8030391

記述言語：英語  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1063/1.5024115

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1063/1.5024097

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1063/1.5024115

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1063/1.5024097

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1177/0263617417692338

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/app8020181

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2017.04.099

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijheatmasstransfer.2016.12.114

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/01457632.2016.1195135

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2016.10.019

記述言語：その他  

Experimental validation of simulated adsorber/desorber beds for sorption cooling applications is essential to obtain reliable results. We have conducted rigorous simulation of the adsorption process occurring in a finned tube adsorber utilizing 2D-axisymmetric geometry. The adsorber uses activated carbon–ethanol as adsorbent–refrigerant pair. It is cooled with water at nearly 30 °C and experiencing a sharp pressure increase of ethanol from 0.95 kPa initially to 6 kPa. The simulated temperatures at adsorbent thicknesses of 0, 1, 5 and 10 mm from tube outer diameter showed an increase in adsorbent temperature up to 20 °C from its initial temperature. They were slightly higher at start of adsorption and were consistent with experimental data at higher flow time. The validated CFD model will serve as a base for evaluating and optimizing activated carbon–ethanol adsorption cooling cycle. It can be extended also to different adsorber designs and other adsorbent–adsorbate pairs.

DOI： 10.1016/j.ijrefrig.2016.10.019

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.expthermflusci.2016.09.011

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（その他学術会議資料等）  

DOI： 10.1063/1.4968250

記述言語：英語  

DOI： 10.1016/j.rser.2016.08.022

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2016.08.004

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2016.08.031

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.expthermflusci.2016.03.021

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2016.05.192

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/01457632.2015.1066650

記述言語：英語  

DOI： 10.1080/01457632.2015.1066645

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2015.12.105

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.renene.2015.09.015

記述言語：英語  

DOI： 10.1016/j.rser.2015.02.038

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10450-015-9663-y

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1615/HeatTransRes.2014007215

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijheatmasstransfer.2014.10.012

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.energy.2014.11.022

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2014.03.062

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

記述言語：英語  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijheatmasstransfer.2014.02.046

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11322/tjsrae.31.1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Design and performance of Four-Stage Adsorption System

記述言語：英語  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/01457632.2012.753571

記述言語：英語  

記述言語：英語  

記述言語：英語  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/en6031365

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/eej.22352

記述言語：英語  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Innovative Design and Performance of Three-Bed Two-Stage Adsorption Cycle under Optimized Cycle Time
This paper presents an innovative design of a three-bed two-stage silica gel-water based adsorption cycle aiming to minimize the overall size of four-bed two-stage cycle. One heat exchanger bed was removed from former four-bed two-stage system and operational strategy was taken to increase the adsorption time compare to desorption time in the proposed design. A simulation model for the proposed cycle was developed in order to analyze the influence of cycle time on the performance of the system in terms of specific cooling power (SCP) and coefficient of performance (COP). The cycle time was optimized to obtain the maximum SCP for different heat source temperatures using the particle swarm optimization (PSO) method. Sensitivity analysis of the cycle time was conducted using contour plot of SCP and chilled water outlet temperature for driving heat source temperature at 55°C. Optimize results were compared with the results of four-bed two-stage cycle. It was found that the SCP was increased for the proposed cycle over the whole range of regeneration temperature. The proposed cycle seems advantageous from the economic viewpoint due to its improved performance and reduced volume.

DOI： 10.1299/jee.7.92

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.enbuild.2011.05.004

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11322/tjsrae.28.269

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/en3111704

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.energy.2010.06.015

記述言語：日本語  

記述言語：英語  

記述言語：英語  

記述言語：英語  

記述言語：英語  

記述言語：英語  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2009.02.008

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/en20401170

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/en20300531

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/en20200202

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2007.07.002

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.energy.2007.05.003

記述言語：英語  

記述言語：英語  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

記述言語：英語  

Fresh fruits and vegetables are perishable and possess short life under ambient conditions. Post-harvest losses are one of the major concerns in the storage of fruits and vegetables. In this regard, proper control of temperature and humidity is required to reduce post-harvest losses and enhance the shelf life of fruit and vegetables with the finest quality, quantity, and nutritive attributes. Several options such as vapor compression-based air-conditioning systems have been studied and implemented worldwide for possible storage of fruits and vegetables but consume a huge amount of energy and degrading the environment. Therefore, in this study, the energy-efficient standalone desiccant air conditioning (DAC) and Maisotsenko cycle-based desiccant air conditioning (M-DAC) systems were explored from the viewpoint of potential storage of fruits and vegetables. The systems analysis to check the feasibility was carried out in the climatic conditions of Multan, Pakistan. The proposed systems were thermodynamically explored from the viewpoint of ideal temperature and humidity control storage zones, cooling capacity, and coefficient of performance (COP). The results appreciably showed that the M-DAC system performed relatively better than the proposed standalone DAC system. It was found that the cooling capacity and COP of the M-DAC system were found 32.5 kJ/kg and 1.07, respectively, as compared with standalone DAC.

DOI： 10.1007/978-3-030-86394-4_4

Scopus

Poultry industries play a major role in Pakistan’s economy as well as developing countries. Poultry birds are sensitive to slight variation in ambient air temperature and humidity. Therefore, temperature-humidity control system is principally required for optimum growth of the birds. Conventionally, vapor-compression-based air-conditioning systems are used in poultry houses to control temperature and humidity. These systems degrade the environment and consume huge amount of primary energy. In this regard, the present study investigates energy-efficient thermally driven desiccant dehumidification-based evaporative cooling system for monthly basis climatic conditions of Multan (Pakistan). The present study explored standalone desiccant air-conditioning system (S-DAC) and Maisotsenko cycle assisted DAC system (M-DAC) using silica-gel and hydrophilic polymeric-sorbent desiccant materials from the viewpoints of slope of dehumidification line, dehumidification capacity, cooling capacity, and coefficient of performance (COP). In addition, the study explored surface temperature, surface area, total sensible heat loss, evaporative heat loss, total heat loss, and temperature-humidity index (THI) of the poultry birds. The results showed that the polymer-based M-DAC system was feasible in terms of maximum dehumidification capacity, cooling capacity, and COP (i.e., 4.3 g/kg-DA, 14.9 kJ/kg, and 0.5, respectively) and achieved thermal comfort (THI &lt; 30℃) of poultry birds throughout the year.

DOI： 10.1007/978-3-030-86394-4_2

Scopus

記述言語：英語   著書種別：学術書

記述言語：英語   著書種別：学術書

DOI： 10.1007/978-3-319-32003-8_22-1

記述言語：日本語   著書種別：学術書

記述言語：英語   著書種別：学術書

記述言語：英語   著書種別：学術書

開催年月日： 2015年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東北大学（仙台）   国名：日本国  

開催年月日： 2015年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東北大学（仙台）   国名：日本国  

開催年月日： 2015年6月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2015年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：福岡国際会議場（福岡）   国名：日本国  

開催年月日： 2015年4月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東京海洋大学（東京）   国名：日本国  

開催年月日： 2015年2月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2014年12月

記述言語：英語   会議種別：口頭発表（一般）  

国名：大韓民国  

開催年月日： 2014年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：海峡メッセ下関，山口   国名：日本国  

開催年月日： 2014年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：佐賀大学，佐賀   国名：日本国  

開催年月日： 2014年6月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2014年6月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2012年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：熊本大学，熊本   国名：日本国  

開催年月日： 2012年9月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：北海道工業大学，北海道   国名：日本国  

開催年月日： 2012年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：北海道工業大学，北海道   国名：日本国  

開催年月日： 2012年6月

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開催年月日： 2018年6月

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記述言語：英語   会議種別：口頭発表（一般）  

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開催年月日： 2017年9月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2017年9月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2017年8月

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開催年月日： 2017年8月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2017年8月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2017年8月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2017年8月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2017年8月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

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記述言語：日本語   会議種別：口頭発表（一般）  

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国名：日本国  

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記述言語：英語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2017年4月

記述言語：英語   会議種別：口頭発表（一般）  

国名：大韓民国  

開催年月日： 2017年4月

記述言語：英語   会議種別：口頭発表（一般）  

国名：大韓民国  

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記述言語：英語   会議種別：口頭発表（一般）  

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開催年月日： 2016年6月 - 2016年7月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2016年6月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2016年5月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2016年5月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2016年5月

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国名：台湾  

開催年月日： 2016年5月

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国名：台湾  

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国名：台湾  

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開催年月日： 2015年10月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2015年10月

記述言語：英語   会議種別：口頭発表（一般）  

国名：台湾  

開催年月日： 2015年10月

記述言語：英語   会議種別：口頭発表（一般）  

国名：台湾  

開催年月日： 2015年10月

記述言語：英語   会議種別：口頭発表（一般）  

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開催年月日： 2015年9月

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国名：日本国  

開催年月日： 2015年8月

記述言語：英語  

国名：日本国  

開催年月日： 2015年8月

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記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2014年9月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国