Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
AKIHITO OZAKI Last modified date:2023.11.22

Professor / Architectural Planning and Environment / Department of Architecture and Urban Design / Faculty of Human-Environment Studies


Papers
1. Muhammad Iqbal, Akihito Ozaki, Younhee Choi, Yusuke Arima, Tomoyuki Hamashima, Investigation of discharge coefficient of louvre openings in naturally ventilated buildings, The 11th International Conference on Indoor Air Quality, Ventilation & Energy Conservation in Buildings, doi.org/10.1051/e3sconf/202339602030, 8, No.02030, 2023.05, Louvre openings are widely used for ventilation in residences at tropical regions. Traditional households rely primarily on natural ventilation for cooling instead of using air conditioners throughout the year. Hence, a design strategy that maximizes the natural ventilation rate with an accurate discharge coefficient is necessary. The discharge coefficient for a traditional window without a louvre is 0.6. However, studies on discharge coefficients for louvre openings with sashes are lacking. Discharge coefficient will differ according to the installed sash owing to increased contraction and friction losses. Therefore, we determined the discharge coefficient value for various sash angles and the impact of the louvre geometric parameter on the discharge coefficient. To investigate the effects of geometry on the discharge coefficient, real-time natural ventilation rate was quantified using the tracer gas (constant concentration) method. Pressure difference, outdoor wind velocity, and temperature difference were also measured. The opening types were divided into three cases: louvres with a sash angle of 0°, 15°, and 30° with similar opening areas. The results show that discharge coefficients for louvres with sash angles of 0°, 15°, and 30° are 0.80, 0.62, and 0.41, respectively, indicating that the coefficient decreases with increasing sash opening angle..
2. Xianzhe Yang, Akihito Ozaki, Ryo Takatsuji, Osamu Nagase, Yusuke Arima, Younhee Choi, Effects of biophilic design on hygrothermal environment and human sensation in a large artificial garden of a public building, The 11th International Conference on Indoor Air Quality, Ventilation & Energy Conservation in Buildings, doi.org/10.1051/e3sconf/202339601085, 8, No.01085, 2023.05, Biophilic design is aimed at creating a good habitat for people by enhancing the connectedness between people and nature in the urban environment; its effects on promoting psychological health are well known, but further studies are required to quantify the effects on physical and physiological aspects to provide a holistic view to support design practice. In this study, we focused on the physical aspect and quantitatively analyzed the effects of biophilic design on the thermal environment and occupants' thermal sensations. Field measurements and questionnaire surveys were conducted at a multifloor indoor garden in a public building in Kumamoto, Japan, with an artificial waterfall, pond, plants, and natural light as biophilic elements. Predicted mean vote was calculated using field measurement results as an objective indicator to assess thermal comfort. Questionnaires were used to verify the psychological effects and clarify the occupants' thermal sensations by comparing with field measurement results. The effects of the waterfall were studied when it was switched on and off. The results suggest the rationality behind incorporating biophilic design inside buildings, in terms of the physical aspect, highlighting the psychological effectiveness, especially during winter, and the benefits of thermal comfort, especially during summer..
3. Yulu Chen, Akihito Ozaki, Haksung Lee, Younhee Choi, Yusuke Arima, Development of an intelligent envelope system with energy recovery ventilation for passive dehumidification in summer and solar collection in winter, The 11th International Conference on Indoor Air Quality, Ventilation & Energy Conservation in Buildings, doi.org/10.1051/e3sconf/202339603025, 8, No.03025, 2023.05, With the aim of establishing a zero-energy housing (ZEH), an intelligent envelope system composed of a passive dehumidification and solar collection system (PDSC system) based on thermodynamic energy theory and an energy recovery ventilation (ERV) unit has been developed, abbreviated as PSE (PDSC & ERV) system, which can be expected to control the indoor hygrothermal environment by using renewable energy further to reduce the heating and cooling demand for the HVAC system. In this study, the measurement experiments were conducted in a wooden house equipped with a PSE system, and the temperature and humidity distributions in the rooms were assessed using thermohygrometer sensors. The field comparison experiments for the three systems (exhaust-only ventilation system, ERV system, and PSE system) were performed separately under various meteorological conditions in summer and winter. The measurement results in summer showed that the PSE system has a significant dehumidification effect compared to the exhaust-only and ERV-only ventilation systems and could effectively reduce the latent heat load caused by ventilation. The measurement results in winter indicated that the PSE system has the effect of heat collection and humidity control as well as reducing the sensible heat load originating from ventilation..
4. Yusuke Arima, Kunihiko Fujiwara, Yasuhiko Azegami, Hajime Iseda, Akihito Ozaki, Younhee Choi, Review of future weather data for building simulations available in Japan and confirmation of its characteristics, The 11th International Conference on Indoor Air Quality, Ventilation & Energy Conservation in Buildings, doi.org/10.1051/e3sconf/202339605014, 8, No.05014, 2023.05, Buildings use a large amount of energy, depending on the climate. To design buildings with high energy and thermal performance in the future, it is necessary to use weather data that reflect future climatic information. Some future weather files for building simulations have been developed. However, these datasets are based on different predictions, and each future weather file has a different creation process. Such methodological differences may lead to differences in predicting the energy and thermal performance of buildings. Understanding the characteristics of each data type is necessary for its appropriate use. However, limited information is available for properly utilizing future weather data for building simulations. This study aims to provide information on the characteristics of future weather data for better utilization. After thoroughly reviewing the existing data and creation methods, we propose a framework for understanding future weather data based on their creative process. We collected five types of future weather datasets available in Japan and compared their characteristics. One of these datasets is the future weather dataset based on climate information provided by the National Institute for Environmental Studies (NIES). We confirmed the degree of variation in each weather element and predicted cooling/heating demand using future weather data available in Japan..
5. Yulu Chen, Akihito Ozaki, Haksung Lee, Energy saving potential of passive dehumidification system combined with energy recovery ventilation using renewable energy, Energy and Buildings, doi.org/10.1016/j.enbuild.2022.112170, Volume 268, 112170, 2022.05, Passive dehumidification and solar collection (PDSC) employs fibrous insulation materials with excellent moisture adsorption and desorption characteristics to conduct dehumidification using renewable energy. This study proposes an improved PDSC-integrated energy recovery ventilation (ERV) system (PSE) to dehumidify indoor environments. Energy recovery ventilation (ERV) promotes the exchange of moisture and heat between returned and supplied air to reduce energy loss caused by ventilation. We explained the fundamental moisture movement principle based on thermodynamic energy and designed the air circulation paths of the proposed system for dehumidification and energy recovery. Five house models were simulated and compared: conventional house with no moisture effect, conventional house, conventional house with integrated ERV, the PDSC model, and the PSE model. Simulation results show that the PSE model has the best dehumidification performance, with an approximately 2.9 times latent heat load reduction effect compared with the PDSC model, in hot and humid summer. This study confirms that the proposed system has significant potential for dehumidifying the indoor environment and provides guidance for the future application of the PSE system to dwellings..
6. Younhee Choi, Akihito Ozaki, Haksung Lee, Impact of Window Frames on Annual Energy Consumption of Residential Buildings and Its Contribution to CO2 Emission Reductions at the City Scale, Energies, doi.org/10.3390/en15103692, Volume 15, No.10, 6-10, 2022.05, Windows are among building components that have the strongest effect on thermal load. They play a significant role in heat loss in buildings because they usually have a largely higher thermal conductance than other components of the building envelope. Although many studies have highlighted the relevance of heat transfer through frames and aimed to improve their thermal performance, poorly insulated aluminum frames (thermal conductivity of aluminum is 160 W/m·K, while that of polyvinyl chloride [PVC] is 0.17 W/m·K) are still in use in Japan. Therefore, the U-values of different window frames were calculated, and annual thermal loads were calculated according to the window configurations, including the frame, glazing, and cavity. We focused on standard residential buildings in Japan with a total floor area of 120.6 m2 (two-story building), and the number of newly built houses and the application rate of window configurations in 2019 were surveyed to estimate the CO2 emissions by regions. CO2 emissions were reduced by approximately 3.98–6.58% with the application of PVC frames. Furthermore, CO2 emissions were converted into the amount of CO2 gas absorbed by cedar trees, which cover nearly 18% of the total land area of Japan. In conclusion, analogous to the amount of CO2 gas absorbed by cedar trees, the absorption effect was equivalent to 327,743–564,416 cedar trees. Changing the window frame material can facilitate a significant energy-saving effect as a considerable amount of energy is saved, especially at a city scale..
7. Younhee Choi, Doosam Song, Akihito Ozaki, Do Energy Subsidies Affect the Indoor Temperature and Heating Energy Consumption in Low-Income Households?, Energy and Buildings, 10.1016/j.enbuild.2021.111678, 256, 1, 111678, 2022.02, As social interest in energy welfare increases, support programs and policies for fuel poverty are steadily being implemented. Energy subsidies play a significant role in improving the indoor thermal conditions affected by fuel poverty. However, various measures to reduce green-house gas emissions in the building sector are being applied. As a result, a balance between energy welfare and energy saving policies is required.
This study aims to analyze the effect of an energy subsidy on improving the indoor temperature and heating energy consumption in low-income dwellings. Long-term and detailed measurements and surveys were conducted for 16 low-income households in an apartment complex in Korea (semi-cold climate). The indoor temperature and heating energy use with/without energy voucher were analyzed. In addition, the annual heating energy consumptions of all 1460 households in the same apartment complex were analyzed.
The results showed that the indoor average temperature of the households receiving the energy subsidy was 24.68 °C, and the households without the energy subsidy were 22.62 °C. In addition, the indoor minimum temperature of the households receiving the energy subsidy was about 1.5 °C higher. The annual heating energy use increased by 59.9% for the older building and 26.6% for the newer building compared with those who did not receive energy subsidies. Energy vouchers have a strong influence on the indoor thermal condition and heating energy consumption of low-income dwellings. The energy subsidy policy for the low-income households needs to be re-examined in terms of energy savings and energy welfare..
8. Tatsuhiro Yamamoto, Akihito Ozaki, Myonghyang Lee, Keigo Aratsu, Ryo Fukui, Development of a Non-Stationary Thermal Environment Analysis Method for Combined Convection and Radiation Air Conditioning, Building and Environment, 10.1016/j.buildenv.2021.108559, 207, Part B, 108559, 2022.01, Advanced thermal environment simulation technology has been developing rapidly in recent years. The thermal environment simulation tools used in thermal engineering can be broadly classified into energy simulations and computational fluid dynamics programs. The combination of these approaches allows the high-accuracy prediction of a non-stationary thermal environment in a continuous space. The main feature of the coupled analysis method is that the radiation is calculated using energy simulation, which reduces the analysis load and makes transient analysis possible. Here, a method was devised for predicting the thermal environment of air conditioners and radiant panels, and its accuracy was verified. By coupling the convective heat transfer coefficient, the maximum mean absolute error of the proposed method was calculated to be 0.674 [-], which is acceptable considering the variable environmental conditions. Although in the acceptable range, this error is attributable to computational fluid dynamics, which is a steady-state analysis and does not fully track the non-stationarity of the radiant panel because of its stop–start nature. The results of this analysis are comprehensive, with the convective heat transfer coefficient calculated using the input conditions for each wall. Regarding the energy simulation, when temperature stratification occurred near a surface, such as the ceiling, a small error was induced because the reference temperature was set to the bulk temperature. However, as the overall trend was captured by the analysis method, these minor errors were deemed acceptable. These results show that the proposed method can be applied to a range of applications, including office spaces..
9. Younhee Choi, Wanghee Cho, Akihito Ozaki, Haksung Lee, Influence of the Moisture Driving Force of Moisture Adsorption and Desorption on Indoor Hygrothermal Environment and Building Thermal Load, Energy and Buildings, 10.1016/j.enbuild.2021.111501, 253, 15, 111501, 2021.12, To more accurately evaluate the indoor hygrothermal environment of a building, control the indoor temperature and humidity, evaluate the thermal comfort of occupants, and select the capacity of the heating, ventilation, and air conditioning (HVAC) system, moisture transfer from and into architectural materials should be considered. However, the most widely used commercialized software ignores the moisture effect from envelopes or adopts a simplified model based on the difference in humidity ratios between hygroscopic materials and interior zone air. In this study, the effects of the driving forces of hygrothermal models were identified and quantified. The calculated results show that the indoor humidity changes differed when the moisture effect by moisture adsorption and desorption was considered in the models. Because the simplified effective moisture penetration depth (EMPD) model uses differences in the humidity ratio as a driving force, the calculated results of the indoor humidity ratio exhibit relatively constant tendencies. However, the thermodynamic chemical potential model corresponds to a detailed heat, air, and moisture transfer (HAM) model that uses the water potential as a driving force; this model can consider the moisture effect based on temperature and humidity changes. Therefore, the humidity ratios calculated using the detailed thermodynamic HAM model show differences of 0.01%–38.78%, and the difference in relative humidity between building materials and indoor air becomes smaller; these results are comparable to those of the simplified model. Finally, the adoption of a simplified model can result in differences in the sensible heat load of 4.4%–13.8% and latent heat load of 16.1%–51.2%. Thus, this study confirmed that a coupled HAM model, which uses the water potential as a driving force, can be employed to accurately simulate the hygrothermal behavior of building envelopes..
10. Tatsuhiro Yamamoto, Akihito Ozaki, Keigo Aratsu, Advanced Thermal Environment and Energy Consumption Calculation Over Time Using Combined Energy Simulation, Computational Fluid Dynamics, and Heat Source Model, Building Performance Simulation, 10.1080/19401493.2021.1992503, 14, 6, 619-645, 2021.11, We developed an unsteady computational simulation tool that sequentially inputs the calculated heat load to a heat source model to determine the coefficient of performance (COP) and power consumption of air conditioners. The accuracy of the energy consumption prediction was improved by incorporating the air-conditioning model into the coupled calculation of energy simulation and computational fluid dynamics as well as reproducing the behavior of equipment efficiency. We conducted a comparative study in an office with a partition in the centre to investigate the effects of short circuits and heat accumulation. The experiments indicated a difference between the bulk temperature of the space and the input air humidity of the air conditioner of ∼2.0°C and 2.5 g/kg (DA), respectively. The coupled analysis confirmed that the power consumption of the bulk temperature/humidity input was ∼100 W and the COP error was ∼2, while the suction temperature/humidity input had high accuracy..
11. Tatsuhiro Yamamoto, Akihito Ozaki, Wall Shear Stress-Based Accuracy Verification of Convective Heat Transfer Coefficient Using Velocity Scale, 47th Annual Conference of the IEEE Industrial Electronics Society, 10.1109/IECON48115.2021.9589217, 21297752, 2021.10.
12. Haksung Lee, Akihito Ozaki, Performance Evaluation of Passive Hygrothermal Control for Houses using a Thermodynamic HAM Model, the 17th International Building Performance Simulation Association Conference, 2021.09.
13. Tatsuhiro Yamamoto, Akihito Ozaki, Myonghyang Lee, Optimal Air Conditioner Placement Using a Simple Thermal Environment Analysis Method for Continuous Large Spaces with Predominant Advection, Energies, 10.3390/en14154663, 14, 2021.07, The number of houses with large, continuous spaces has increased recently. With improvements in insulation performance, it has become possible to efficiently air condition such spaces using a single air conditioner. However, the air conditioning efficiency depends on the placement of the air conditioner. The only way to determine the optimal placement of such air conditioners is to conduct an experiment or use computational fluid dynamic analysis. However, because the analysis is performed over a limited period, it is difficult to consider non-stationarity effects without using an energy simulation. Therefore, in this study, energy simulations and computational fluid dynamics analyses were coupled to develop a thermal environment analysis method that considers non-stationarity effects, and various air conditioner arrangements were investigated to demonstrate the applicability of the proposed method. The accuracy verification results generally followed the experimental results. A case study was conducted using the calculated boundary conditions, and the results showed that the placement of two air conditioners in the target experimental house could provide sufficient air conditioning during both winter and summer. Our results suggest that this method can be used to conduct preliminary studies if the necessary data are available during design or if an experimental house is used..
14. Haksung Lee, Akihito Ozaki, Younhee Choi, Muhammad Iqbal, Performance Improvement Plan of Air Circulation-Type Solar Heat-Storage System Using Ventilated Cavity of Roof, Energies, 10.3390/en14061606, 14, 6, 2021.05, Indoor solar-heating systems that use ventilated roofs have drawn attention in recent years. The effectiveness and efficiency of such air-heating systems vary depending on the design and operation methods. In Japan, by introducing outside air into a ventilated roof cavity and circulating the air indoors, systems that simultaneously obtain ventilation, solar heating, and heat-storage effects have been actively developed. The conventional systems intake a large volume of outside air to increase the solar heat collection effect. However, there is a risk of heat loss and over-drying when a large amount of cold dry air during winter is introduced. In this paper, plans are presented for improving these solar heating and heat-storage effects by preventing over-drying using indoor air circulation via ventilated cavities in the roof and indoor wall. By comparing the results of the proposed system with those of the conventional system via numerical simulation, the heating load is found to be reduced by 50% or more by circulating indoor air to the ventilated roof and storing the heat in the indoor wall. Moreover, an increased relative humidity of approximately 10% was confirmed by reducing the intrusion of the outside air and keeping the moisture indoors..
15. Tatsuhiro Yamamoto, Akihito Ozaki, Suehiro Kaoru, Kazuhiro Taniguchi, Analysis Method Based on Coupled Heat Transfer and CFD Simulations for Buildings with Thermally Complex Building Envelopes, Building and Environment, 191, 15, 2021.03, 円錐台形状の盛り土建築を対象として,外皮を8方位に分割して2次元熱伝導計算を導入し,さらにCFDと連成することで近似的に3次元の熱・気流拡散を予測する方法(ESとCFDの連成計算に2次元伝熱計算プログラムを補填する拡張計算法)を提案した。3次元熱伝導が生じる外皮形状の建築を対象とする場合のESとCFDの連成計算法の確立するとともに,実験結果を再現することで計算方法の妥当性について明らかにした。.
16. Haksung Lee, Akihito Ozaki, Housing design methodology for passive hygrothermal control and effect verification via field measurements, Building and Environment, 10.1016/j.buildenv.2020.107241, 185, 2020.11, With the aim of designing a passive home that exhibits constant hygrothermal control performance using renewable energy, we develop a high-performance envelope system characterized by dehumidification/radiative cooling in hot and humid summers and humidity control/heating in cold and dry winters, which can be applied to homes (which are based on a dry construction method) using mainly industrial building materials. We have previously conducted laboratory experiments using a roof model and numerical simulations. Using these studies, we design and construct a full-scale home to verify the applicability and effectiveness of this system in actual homes. In this paper, we propose a housing design method that can control the temperature and humidity by introducing a system that uses renewable energy, as well as confirming the effects of passive dehumidification, radiative cooling, and solar heat collection via field measurements using demonstration homes. As an example of the experimental results, the relative and absolute humidity in the home with the proposed system were reduced by approximately 11% and 3.2 g/kg, respectively, in comparison with the home without the system during the humid summer season, thus clarifying the dehumidification effect of this system..
17. Yang He, Hang Yu, Akihito Ozaki, Nannan Dong, Thermal and energy performance of green roof and cool roof
A comparison study in Shanghai area, Journal of Cleaner Production, 10.1016/j.jclepro.2020.122205, 267, 2020.09, Green roofs and cool roofs are commonly used to improve indoor thermal environment, reduce air-conditioning load and mitigate the Urban Heat Island (UHI) effect. This study aimed to quantify the differences in thermal and energy performance between the two different roof types under the climate of Shanghai. Firstly, field experiment was conducted in the Shanghai area. Thermal performance of green roof, cool roof and common roof in summer and winter were measured. Results showed that, compared to common roof, the cool roof had an average cooling effect of 3.3 °C on the outer roof deck surface in summer, while the green roof only had a cooling effect of 2.9 °C. In winter, the green roof provided good insulation, and could improve outer surface temperature of the roof deck by an average of 3.3 °C compared to the cool roof. A hygrothermal transfer model for green roof was coupled with a dynamic building thermal performance simulation software (THERB) and validated using measured data. The coupled model was used to predict the effect of both roof types on energy performance of a public building. Simulation results showed that green roof could reduce the cooling and heating loads of the top floor by 3.6% and 6.2%, respectively. The cool roof could reduce cooling load by 3.6% and increase heating load by 10.4%. Finally, a parametric analysis was implemented. The functional mechanism of the main parameters of green and cool roof as well as their impacts on thermal and energy performance of public buildings were analyzed in detail. Conclusions drawn from this paper could provide guidance for the design optimization and application of green roof and cool roof in Shanghai area..
18. Haksung Lee, Akihito Ozaki, Myonghyang Lee, Takahiro Yamamoto, Humidity control effect of vapor-permeable walls employing hygroscopic insulation material, Indoor Air, 10.1111/ina.12622, 2019.11, Airtight construction and high-performance thermal insulation materials are commonly considered important building features to enhance indoor thermal comfort while reducing thermal load. However, when water vapor is generated in such airtight indoor spaces, it cannot be discharged to the outside, causing interstitial condensation and subsequent intrusion of moisture into the walls. Hygroscopic building materials such as cellulose fiber insulation (CFI), characterized by high water capacity, are a potential countermeasure against such condensation. In this study, the humidity control performance of external walls containing CFI was evaluated using data measured inside a demonstration house and calculated by numerical simulations based on thermodynamic chemical potential theory. The changes in moisture adsorption and desorption were then evaluated for different wall constructions and different climate conditions using a parameter sensitivity analysis. Finally, the effective application of CFI to prevent interstitial condensation was confirmed by comparing different wall compositions..
19. LEE Haksung, OZAKI Akihito, CHO Wanghee, LEE Myonghyang, Smart Passive System for Dehumidification, Cooling, and Heating Utilizing Renewable Energy in Detached House, International Building Performance Simulation Association, 2442-2449, 2019.09.
20. Tatsuhiro Yamamoto, Akihito Ozaki, Myonghyang Lee, Development of a thermal environment analysis method for a dwelling containing a colonnade space through coupled energy simulation and computational fluid dynamics, Energy, 10.3390/en12132560, 12, 13, 2019.07, In building design, several approaches have been proposed for coupling computational fluid dynamics (CFD) and energy simulation (ES) to perform analyses of thermal environments. The unsteady analysis of thermal environments within buildings containing offices and colonnade spaces is difficult to perform using an ES that represents the space with a single mass point, owing to excessive predictive heat loss; therefore, CFD has typically been used instead. Although it is possible to divide the space into zones using ES, it leads to excessive predicted heat loss and the prediction of heat movement due to the influence of strong air currents, such as those associated with air conditioners. This behavior is observed because these zones are not detailed mesh divisions. To solve these problems, we proposed a method for calculating the ratio of heat contribution to zones that were pre-divided using CFD followed by the distribution of the total thermal load calculated by ES. In this study, we proposed a method for coupling ES and CFD, which enabled the unsteady analysis of a thermal environment in a large space and verified its accuracy..
21. Haksung Lee, Akihito Ozaki, Myonghyang Lee, Wanghee Cho, A fundamental study of intelligent building envelope systems capable of passive dehumidification and solar heat collection utilizing renewable energy, Energy and Buildings, 10.1016/j.enbuild.2019.04.039, 195, 139-148, 2019.04, Experimental studies and simulation analysis were conducted to assess the hygrothermal performance of intelligent roof systems, which perform passive dehumidification in summer and solar heat collection in winter by air circulation through the roof ventilation layer to reduce sensible and latent heat load using solar heat. A high-efficiency air conditioning system separating latent and sensible heat can be developed using fibrous insulation with excellent moisture conditioning properties. The thermodynamic-potential-based fundamental principle of the intelligent skin system, which performs passive dehumidification and solar collection, was explained based on non-equivalent thermodynamics. The performance characteristics of temperature and humidity fluctuations of the intelligent roof were experimentally and numerically demonstrated. This work enables the combined analysis of heat and moisture movement in the envelope system. The experimental and numerical simulation results indicate that significant sensible and latent heat reduction can be achieved by running the system using renewable energy..
22. H. Lee, Akihito Ozaki, W. Cho, Evaluation of Anti-condensation Performance of External Walls with Fibrous Insulation, 4th Asia Conference of International Building Performance Simulation Association, ASIM 2018 IOP Conference Series: Earth and Environmental Science, 10.1088/1755-1315/238/1/012013, 238, 1, 2019.03, In recent years, there has been a tendency to focus on high airtightness and the thermal insulation performance of houses for the purpose of the improvement of the indoor heat environment and reduction in the heating and cooling loads. However, the high airtightness and insulation performance increase the risk of intrusion into the inside of the wall, which causes interstitial condensation because the water vapor generated in the room cannot be discharged to the outside. In this study, we evaluate the anti-condensation performance of the walls using cellulose-fiber-based heat insulation (CF), which has a large moisture capacity and excellent moisture adsorption and desorption performance. The usefulness of CF is confirmed by clarifying the occurrence of internal condensation through measurement data analysis of a demonstration house, as well as numerical simulations..
23. Tatsuhiro Yamamoto, Akihito Ozaki, Myonghyang Lee, Improving the Prediction Accuracy of Power Consumption and COP by Coupling ES and CFD Incorporated in a Heat Source Characteristic Model, The 4th Asia Conference of International Building Performance Simulation Association, 9, ID368, 2018.12.
24. Haksung Lee, Akihito Ozaki, Wanghee Cho, Evaluation of Anti-condensation Performance of External Walls with Fibrous Insulation, The 4th Asia Conference of International Building Performance Simulation Association, 8, ID372, 2018.12.
25. Haksung Lee, Akihito Ozaki, Sensitivity analysis for optimization of renewable-energy-based air-circulation-type temperature-control system, Applied Energy, 10.1016/j.apenergy.2018.08.111, 230, 317-329, 2018.11, A detailed investigation of thermal performance of an air-circulation-type temperature-control system to serve as an alternative means of saving energy and heat storage is reported. The proposed system is of the hybrid type combining a central air-conditioning system, system incorporating phase-change material (PCM), and a roof-ventilation layer. The said hybrid system was tested by means of an experiment performed in an actual house located in Yufuin in the Oita prefecture in Japan. Numerical analysis was performed using Hygrabe—an unsteady heat-transfer-analysis tool—for the building envelope. Results of the said experiment were observed to accurately predict the effects of radiative cooling, exhaust cooling, cold storage and release in summer, solar-heat collection, and heat storage and release in winter. The potential for improved operation of the proposed system was demonstrated via parameter sensitivity analysis, which quantified the change in each effect along with resulting correlations deduced based on changes brought about in individual factors, such as air velocity, roof length, and PCM box. The proposed study, therefore, facilitates development of design guidelines for temperature-control systems to be installed in high-performance passive homes..
26. Debata Ayano, Hiroatsu Fukuda, and Akihito Ozaki, Study on Cooling Load Reduction Effect of Apartment Housing Performed Temperature and Humidity Control Ventilation during summer, Under-floor Condensation and Suppression of Mold Growth in the Room, Journal of Asian Institute of Low Carbon Design, 13-18, 2018.11.
27. Yuko Kuma, Yusuke Nakaya, and Akihito Ozaki, Construction of the User Support System for Performance Evaluation Tool of Building Environment, Journal of Asian Institute of Low Carbon Design, 39-42, 2018.11.
28. Hama, Yohei, Hiroatsu Fukuda, Takumi Kobatake, Myonghyang Lee, and Akihito Ozaki, Study on the High Humidity in The Underfloor Space of Detached Houses During Summer: Examination on the Optimal Control Methods of Forced Ventilation in Underfloor Space Using Numerical Calculation, Journal of Asian Institute of Low Carbon Design, 215-220, 2018.11.
29. Qingsong Ma, Hiroatsu Fukuda, Myonghyang Lee, Takumi Kobatake, Yuko Kuma, Akihito Ozaki, Study on the utilization of heat in the mechanically ventilated Trombe wall in a house with a central air conditioning and air circulation system, Applied Energy, 10.1016/j.apenergy.2018.04.010, 222, 861-871, 2018.07, This paper presents a study on a mechanically ventilated Trombe wall that adds additional windows to the storage wall. The mechanically ventilated Trombe wall is located on the south side of the house with a central air conditioning and air circulation system. To reduce the heating load, during the heating period, the heat from the Trombe wall air channel is sent to the air conditioning room, from where it is then distributed and stored throughout the house by way of air circulation. Taking a house located in Miyazaki, Japan as an example, we conducted an actual survey to understand the situation of heat utilization of the Trombe wall and used numerical simulations to examine the effective method of heat utilization of the Trombe wall. Results showed that in all-day air conditioning, even when sending the air in the Trombe wall to the air-conditioned room, the temperature of the Trombe wall remained high. The heating load was reduced by sending the air from the Trombe wall to the central air-conditioned room and installing the large heat capacity material on the floor in the Trombe wall..
30. Haksung Lee, Akihito Ozaki, Intelligent Roof System Utilizing Renewable Energy to Reduce Heat Loads, Grand Renewable Energy, Japan Council for Renewable Energy, 4, 73, 2018.06.
31. Qingsong Ma, Hiroatsu Fukuda, Myonghyang Lee, Akihito Ozaki, Numerical Simulation of Double-Layer Trombe Wall with Energy Performance Analysis, Grand Renewable Energy, Japan Council for Renewable Energy, 4, 74, 2018.06.
32. Qingsong Ma, Hiroatsu Fukuda, Myonghyang Lee, Takumi Kobatake, Yuko Kuma, Akihito Ozaki, Xindong Wei, Experimental analysis of the thermal performance of a sunspace attached to a house with a central air conditioning system, Sustainability, 10.3390/su10051428, 10, 5, 2018.05, In this paper, the thermal performance of a sunspace attached to a house with a central air conditioning system was experimentally investigated. The house with a south-facing sunspace is located in Miyazaki, Japan, where heating is required in winter. In order to reduce the heating energy in winter, the hot air from the attached sunspace is sent to the central air conditioning room, from where it is then distributed and stored throughout the house by way of air circulation. Only when the temperature in the sunspace exceeds 24 °C is the hot air in the sunspace sent to the central air conditioning room. The air circulation between the attached sunspace and central air conditioning room is 500 m3/h. The temperature of the attached sunspace and each room were measured. The results showed that a house with a sunspace can save about 12.2% of energy compared to a house without a sunspace..
33. Tatsuhiro Yamamoto, Akihito Ozaki, Myongyang Lee, Hideki Kusumoto, Fundamental study of coupling methods between energy simulation and CFD, Energy and Buildings, 10.1016/j.enbuild.2017.11.059, 159, 587-599, 2018.01, We have developed a new coupling method between energy simulation (ES) and computational fluid dynamics (CFD). First, the validity of the coupling method in the stationary part is verified, and the temperature distribution of the space is predicted. At this time, we compare whether it is better to use a temperature boundary for the high boundary conditions or a heat flow boundary. An ES cannot consider the spatial temperature distribution, but it is possible to divide the space into any number of divisions. Since the amount of advection of the cross section of the space of the divided analysis model is not known, the temperature distribution of the space can be reproduced, even by ES, by integrating the values calculated by CFD. In this study, we clarify that the temperature distribution in an environment where natural convection by floor heating is dominant can be reproduced in detail by a combination of ES and CFD. We also conduct a fundamental study of a method for predicting the temperature of an arbitrarily divided zone in a large space. As a result, the temperature distribution when the amount of advection is coupled is clarified..
34. Qingsong Ma, Hiroatsu Fukuda, Myonghyang Lee, Takumi Kobatake, Yuko Kuma, Akihito Ozaki, Xindong Wei, Study on heat utilization in an attached sunspace in a house with a central heating, ventilation, and air conditioning system, Energy, 10.3390/en11051192, 11, 5, 2018.07, Based on numerical simulations, the heating load reduction effect of an attached sunspace in winter was determined, and the effective heat utilization method and sunspace design were explored. In this paper, we studied the heating load reduction effect using heat from the sunspace and temperature fluctuation of each room at the time of heat use from the sunspace (sending air from the sunspace to the heating, ventilation, and air conditioning (HVAC) machine room and taking the air to the adjacent rooms). In the case of the all-day HVAC system, it was confirmed that a larger capacity of sunspace and not sending air from the sunspace to the adjacent room demonstrated a better heating-load reduction effect. Compared with Model Iw (a house with a window on the exterior of the sunspace opened to external air), Model I (a house with an attached sunspace on the second floor) could save approximately 41% of the total energy. Model II (a house with the attached sunspace both on the first and second floors) could save approximately 84% of the total energy. Sending heat from the sunspace to the adjacent room led to temperature increases in the adjacent rooms. However, if the construction plan is to have the sunspace only on the second floor, the house should be carefully designed, for example, by placing a living room on the second floor..
35. Yang He, Hang Yu, Akihito Ozaki, Nannan Dong, Shiling Zheng, Influence of plant and soil layer on energy balance and thermal performance of green roof system, Energy, 10.1016/j.energy.2017.08.064, 141, 1285-1299, 2017.12, This paper aims to make clear the effects of two important parameters, namely thickness of soil layer and leaf area index of plant layer, on green roof energy and thermal performance. Based on a coupled hygrothermal transfer model validated by field experiments in Shanghai area, energy balance of plant and soil layer is analyzed. Then 18 cases are simulated for different combinations of soil thickness and leaf area index, the results show that soil thickness has a significant effect on long term thermal performance of green roof in both summer and winter, while the effect of leaf area index is only great in summer. Compared with the hypothetical case without evaporation and transpiration, it is found that evaporation of soil layer makes a greater contribution in summer but a less one in winter compared with insulation effect of soil layer. For plant layer, shading is the main cooling way of roof deck while transpiration plays a minor role. Finally, based on the simulation results of long-term thermal performance, two new indexes are proposed to evaluate the relative thermal characteristic of green roof. And the influences of soil thickness, leaf area index and evapotranspiration on the two indexes are analyzed respectively..
36. Haksung Lee, Akihito Ozaki, Myonghyang Lee, Energy saving effect of air circulation heat storage system using natural energy, Building and Environment, 10.1016/j.buildenv.2017.08.007, 124, 104-117, 2017.11, A central air circulation system that uses a roof ventilation layer and a phase change material (PCM) unit is proposed as a possible means of controlling thermal load and peak load. The central air-conditioning air-circulation-type system enables reduction of sensible heat load and facilitates radiative cooling/forced heat exchange in summer, and solar heat collection in winter, via the roof ventilation layer; thereby improving efficiency. The PCM unit is incorporated into the air circulation route to store the cold energy of the cooled air by radiative cooling and the heat energy of the heated air by solar heat collection. The actual measurement results of an experimental house were analyzed and numerical simulations were performed to evaluate the effective sensible heat and peak load reductions. The quantitative simulation and experimental results indicate that significant sensible heat reduction can be achieved by employing the proposed system, which uses natural energy to reduce the energy consumption of indoor temperature control..
37. Yang He, Hang Yu, Akihito Ozaki, Nannan Dong, Shiling Zheng, A detailed investigation of thermal behavior of green envelope under urban canopy scale in summer
A case study in Shanghai area, Energy and Buildings, 10.1016/j.enbuild.2017.03.014, 148, 142-154, 2017.08, As a building component with long history, green envelope has received much attention for its thermal and energy benefits in the past decades. However, few studies have taken into account the two-way effect of green envelope on indoor and outdoor environment during thermal performance evaluation. In this paper, a coupled hygrothermal transfer model of green envelope is developed and validated against field measurements, and the results demonstrate that the model could reasonably reproduce temporal variations of temperature and moisture in green envelope. Then the green envelope model is implemented into an urban canopy model to predict its thermal performance under urban canopy context in Shanghai area. The simulations for a district of office buildings indicate that green envelope decreases sensible heat getting into the indoor and outdoor space significantly, and the maximum indoor temperature difference between buildings with and without green envelope is up to 0.34C under free-floating condition. Meanwhile, for outdoor environment, the maximum differences for air temperature, mean radiant temperature and SET* are up to 0.1,0.9 and 0.2 °C respectively under air conditioning condition. What's more, sensitivity analysis shows that building density has a significant effect on the relative cooling benefit of green envelope against common envelope..
38. Yang He, Hang Yu, Akihito Ozaki, Nannan Dong, Shiling Zheng, Long-term thermal performance evaluation of green roof system based on two new indexes
A case study in Shanghai area, Building and Environment, 10.1016/j.buildenv.2017.04.001, 120, 13-28, 2017.08, It's widely accepted that green roof systems exhibit varying thermal performances compared with common roofs, nonetheless, there are lack of indexes to characterize this difference with regards to internal mechanisms. In light of this condition, this paper presents two new indexes, namely insulation factor (φ) and comprehensive temperature regulation factor (β) based on insulation and passive cooling effect of the green roof. In order to predict long-term thermal performance of green roof in Shanghai area, a coupled heat and moisture transfer model is developed and validated by measurement data. Based on this model, green roof thermal performances are simulated under different indoor temperatures, and two indexes under different seasons are calculated. The results demonstrate that φ changes little around the year while β varies greatly. To make clear the variation rule of these two indexes, a sensitivity test is carried out. It's observed that thermal resistance of substrate layer and corresponding common roof are the main influence parameters of φ, while β is affected mostly by leaf area index, surface reflectivity and emissivity of substrate layer and common roof. In practice, these two indexes could be used to evaluate the relative thermal performance of different types of green roof against corresponding common roof..
39. Yang He, Hang Yu, Akihito Ozaki, Nannan Dong, Shiling Zheng, An investigation on the thermal and energy performance of living wall system in Shanghai area, Energy and Buildings, 10.1016/j.enbuild.2016.12.083, 140, 324-335, 2017.04, In order to analyze thermal and energy performance of living wall system in Shanghai area, a coupled heat and moisture transfer model is developed and validated by filed experiments. The measurement results prove that living wall has a better thermal performance than corresponding common wall in summer and winter. And an energy balance analysis is conducted to elucidate the difference of heat transfer mechanism between living wall and common wall. Based on the model, the impact of orientation on thermal performance of living wall is simulated and analyzed in summer and winter. Furthermore, additional equivalent thermal resistance is calculated to evaluate the average thermal performance of living wall according to the long-term simulation results of both walls. It's found that the additional equivalent thermal resistance of living wall in summer is obviously higher than that in winter. Finally, a sensitivity test is carried out to distinguish the significant factors that affect long-term thermal performance of living wall, including plant parameters, substrate parameters, structure layer parameters, indoor condition, weather parameters and irrigation frequency. The model in the paper helps to optimize the design of living wall to get a better thermal benefit and judge whether living wall satisfies the local rule of energy conservation..
40. 隈 裕子,尾崎明仁,住吉大輔,原口紘一,李 明香, Study on Indoor Thermal Environment and Sensitivity Analysis of a Passive Method with Solar Heat Utilization House, Proc. of the 3rd Asia conference of International Building Performance Simulation Association, 8, Asim 2016,ID349, 2016.11.
41. 田安未奈,尾崎明仁, An Optimization study on Temperature based Automatic windows opening of highly insulated soil walls residential building, Proc. of the 3rd Asia conference of International Building Performance Simulation Association, 8, Asim 2016,ID309, 2016.11.
42. 李 明香,近本智行,尾崎明仁,岡本 茂,小﨑麻莉菜, The Effects of the Physiological Response of the Human Body and the Human Sensation by using the Directional or the Diffusible Airflow of the Personal Air-conditioning System, Proc. of the 3rd Asia conference of International Building Performance Simulation Association, 8, Asim 2016,ID296, 2016.11.
43. 李 学成,尾崎明仁,李 明香,丸岡祐輔, Analysis on Passive Dehumidification and Ventilation System based on Thermodynamic Energy, Proc. of the 3rd Asia conference of International Building Performance Simulation Association, 8, Asim 2016,ID269, 2016.11.
44. 岩崎祐加,尾崎明仁, A Study on Internal Condensation of Roof Systems with Consideration of Heat Bridge Effect, Proc. of the 5th International Conference on Human-Environment System, 6, ICHES2016,No.20066, 2016.10.
45. 隈 裕子,尾崎明仁,住吉大輔,李 明香,原口紘一,中池和輝, Study on Solar Heat System which Combined Passive and Active Heating Technique with the Central Air Conditioning and Circulation System of House, Proc. of the 5th International Conference on Human-Environment System, 9, ICHES2016,No.20065, 2016.10.
46. 田安未奈,尾崎明仁, An optimization study on temperature-based automatic windows opening in highly insulated soil walls of residential buildings, Proc. of the 5th International Conference on Human-Environment System, 7, ICHES2016,No.20063, 2016.10.
47. 李 学成,尾崎明仁,丸岡祐輔,瀬崎幹仁, Performance Evaluation on Dew Proofing and Humidity Conditioning of Exterior Walls with Characteristics of Moisture Absorption and Desorption, Proc. of the 5th International Conference on Human-Environment System, 9, ICHES2016,No.20052, 2016.10.
48. 何 旸,于 航,尾崎明仁,董楠楠, Equivalent Thermal Resistance Evaluation of Green Roof System in Shanghai District, Proc. of the 5th International Conference on Human-Environment System, 10, ICHES2016,No.20048, 2016.10.
49. Myonghyang Lee, Akihito Ozaki, Tomoyuki Chikamoto, Analysis of an indoor environment with a hydronic floor-heating syste under the sensory index, Journal of Environmental Engineering (Japan), 10.3130/aije.81.65, 81, 719, 65-71, 2016.01, Recent buildings are required to not only energy conservation but also healthy and amenity for residents. The active systems (radiant heating and cooling system, personal air conditioning system, etc.) and the passive systems (natural draft, solar heat gain, etc.) for energy conservation are suggested to accomplish both performances. Therefore, the quantitative estimation including human sensation of hygrothermal environment and energy performance based on these systems is important. Generally simulation software to predict temperature, humidity, heating and cooling load of building spaces does not take into account of human sensation under non-uniform environment such as radiant heating and cooling system. THERB is dynamic simulation software that can estimate temperature, humidity, the sensory index, and the heating and cooling load for multiple-zone buildings and wall assemblies. The heat and moisture transfer models used in THERB, such as those for conduction, convection, radiation, and ventilation (or air leakage), are based on detailed phenomena describing actual building physics. These models can be applied to all forms of building design, structure, or occupant schedules. All of these phenomena are typically calculated without simplifying the heat and moisture transfer principles of any building component or element. Thus, THERB can predict the hygrothermal environment of the whole building, taking into consideration the complex relationship between heat and moisture transfer and airflow. This paper explains the prominent features of the calculation models, and investigates the accuracy of THERB by comparison with a test house equipped with a hydronic floor-heating system. It was found that THERB could predict the thermal environment of a room equipped with a hydronic floor-heating system with absolute accuracy. Subsequently, the sensory index "COMSET," based on the hygrothermal balance of the various parts of the human body, is calculated in case of the non-uniform thermal environment of floor heating, with a combination of THERB. Sensitivity analyses of the heating system and the sensory index provide the following results. 1) Even if the values of COMSET remain constant, the room air temperature rises when the heating system is changed in the following order: space conditioning, floor heating in a standing position, and floor heating in a sitting position, to cause a sense of warmth. 2) The floor-heating system has the ability to decrease the heating load dramatically, depending on the physical posture, if the radiative heat and the contact thermal conductance from the floor for each part of the human body are realistically considered as control requirements of heating..
50. Seongmin Yeun, Satoru Sadohara, Akihito Ozaki, Yuichi Sato, Satoshi Yoshida, Makoto Kawase, The analysis of the causes of underground warming using numerical simulation, Journal of Environmental Engineering (Japan), 10.3130/aije.81.111, 81, 719, 111-121, 2016.01, The underground thermal environment shows a complex structure that is affected by the topography, geological features, flow of underground water, rise in temperature from urbanization, the landcover composition and so on. For the purpose of understanding the underground thermal environment, this study measured the ground temperature of gauge wells in the center of Hadano City, Kanagawa. In general, thermal temperature remains constant all year round at a certain depth from the ground surface. But, actual measurement results showed that the closer to the ground surface, the higher the annual temperature. This study, for the purpose of analyzing the causes of underground warming, calculated the underground temperature through numerical simulation and reviewed how changes in the landcover composition structure that forms the ground surface and the temperature rise from urbanization affect underground temperature. In the numerical simulation, a complex moving model consisting of air, vegetation, heat, moisture and air was used to analyze the heat due to actual phenomena, with detailed consideration given to the effect of vegetation or the movement of moisture in the ground. The calculation results show that the gauge well of Hadano City and the underground temperature measured at 12m were almost the same, confirming the accuracy of the numerical simulation. Calculation results from areas with various landcover compositions such as green areas, barren areas and asphalt-covered areas were compared and the rising temperatures over the past 50 years in Hadano City were also taken into account to conclude that rising temperatures from urbanization, changes in the ground surface landcover composition, flow of underground water have an effect on underground temperature..
51. Daisuke Sumiyoshi, Yuki Okuda, Yasunori Akashi, Akihito Ozaki, Toshiyuki Watanabe, The examination for suitable spec of solid oxide fuel cell co-generation system and the proposal of tank minimization by using bas-tab in collective housing, Journal of Environmental Engineering (Japan), 10.3130/aije.80.441, 80, 711, 441-450, 2015.01, In this report, the optimized rated power output and the optimized hot water tank capacity of SOFC in accordance with the energy demand of collective housing are clarified. And authors proposed "the bathtub heat storage operation" and clarified its efficiency. The conclusions are as follows. 1. The optimized rated power output related with the total annual demand of electric power and hot water supply. The optimized hot water tank capacity related with the heat-to-power ratio of demand. 2. "The bathtub heat storage operation" was effective in the cases where the hot water tank capacity was less than 30L. It shows that it was possible to make the hot water tank for collective housing smaller without greatly lowering the energy saving efficiency of SOFC..
52. 尹 晟敏,川瀬 誠,尾崎明仁,佐藤裕一,佐土原聡, The Analysis of the Cause of Underground Warming Using Numerical Simulation, Proc. of the 2nd Asia Conference of International Building Performance Simulation Association, 786-793, Asim 2014, 2014.11.
53. 谷 直樹,尾崎明仁, Fundamental Study on the Moisture Desorption Characteristics of Water-Saturated Concrete, Proc. of the 2nd Asia Conference of International Building Performance Simulation Association, 523-530, Asim 2014, 2014.11.
54. 岩山遼太郎,尾崎明仁, Research on Temperature and Relative-Humidity Change Caused by Renovations, Proc. of the 2nd Asia Conference of International Building Performance Simulation Association, 515-522, Asim 2014, 2014.11.
55. 重森康太郎,尾崎明仁, Net Zero Energy House utilizing solar power, Proc. of the 2nd Asia Conference of International Building Performance Simulation Association, 451-458, Asim 2014, 2014.11.
56. 李 明香,尾崎明仁, Analysis of an Indoor Environment with a Hydronic Floor-Heating System under the Sensory Index, Proc. of the 2nd Asia Conference of International Building Performance Simulation Association, 435-442, Asim 2014, 2014.11.
57. Akihito Ozaki, Genki Inoue, Yumi Ozaki, Myonghyang Lee, Future prospects of the household energy consumption
Scenario building of energy conservation for Hadano, Journal of Environmental Engineering (Japan), 10.3130/aije.79.489, 79, 700, 489-497, 2014.06, Lifestyle of households has been changed to expect hygrothermal comfort and healthy environment through widespread use of space conditioning equipment. Meanwhile, energy conservation in buildings is strongly demanded for effective utilization of energy and resources and for environmental preservation. Therefore, optimization of architectural planning with consideration of future changes in building performance and lifestyle are necessary to maintain a balance between energy conservation, hygrothermal comfort and healthy environment. In this paper, household energy consumption is calculated according to applications of heating, cooling, hot-water supply, lighting, electrical appliances, etc. The calculation accuracy is confirmed through comparison with survey findings. Then the simplified prediction formulas of household specific energy consumption are created with multiple regression analysis based on the sensitivity analysis of dynamic energy simulation. And the many cases of household specific energy consumption variation with building specifications and family configuration are calculated. Furthermore, future prospects of the household energy consumption on single-family houses and multiple dwelling houses are examined with future changes of family configuration and building specifications in Hadano by 2030. As the result, it is clarified that the household energy consumption in 2030 will be likely to increase by 10.3% in single-family houses and by 1.4% in multiple dwelling houses by comparison with 1990 levels in case with no energy conservation measures. However it is possible to reduce household energy consumption by up to 38.3% and 36.3% in both houses in a case with energy conservation measures..
58. 李 明香,尾崎明仁,前田実可子, Development of Energy-Efficient Houses Equipped with Central Duct Space-Conditioning System and Solar Collector, Transaction on Control and Mechanical Systems, Vol.3, No.1, 71-75, 2014.05.
59. 李 明香,尾崎明仁,隈 裕子, Numerical Simulation on Hygrothermal Environment of whole Buildings Taking into Account Complete HAM Features, Transaction on Control and Mechanical Systems, Vol.3, No.1, 52-58, 2014.01.
60. 尾崎明仁,李 明香,隈 裕子, Prediction of Sensory Index under Non-Uniform Thermal Environment Based on Heat and Moisture Transfer and Airflow of Whole Buildings, Proc. of the 13th International Building Performance Simulation Association Conference, 8, BP-3, Building Simulation 2013, 2013.08.
61. Myonghyang Lee, Akihito Ozaki, Analysis on living environment of heat insulation and air-tight houses utilizing hygrothermal property of red pine plank, Journal of Environmental Engineering (Japan), 10.3130/aije.77.967, 77, 682, 967-976, 2012.12, Due to the enforcement of the "Energy Conservation Standard for Housing" and the "Housing Performance Indication Law" in Japan, insulation and air-tightness have been all the more emphasized and have drastically advanced. However the factors significantly interconnected to the comfort such as indoor humidity variation arisen from human living with moisture sorption and desorption of walls have been disregarded. In this paper, red pine plank is utilized as the interior finishing material with moisture sorption and desorption characteristics to provide the function with constant temperature and humidity to insulation and air-tight houses. The model experiments in reference to temperature and humidity response method, the actual measurement of hygrothermal environment of houses, and the numerical simulation have examined the influence of the red pine plank on the indoor environment. The simulation software "THERB" which has complete HAM features (heat and moisture transfer and airflow) including principles of moisture transfer within walls is used and its accuracy is also verified through the comparison of the calculations and the experiments. As the results, the effects of the red pine plank to prevent humidity increase in rainy season and over dryness during heating are clarified. Then constant temperature capability caused by thermal storage within the red pine plank is also demonstrated..
62. 李 明香,尾崎明仁,前田実可子, Development of Energy-Efficient Houses Equipped with Central Duct Space-Conditioning System and Solar Collector, Proc. of Asim2012 - The 1st Asia Conference of International Building Performance Simulation Association, 8, ID0101, 2012.11.
63. 佐藤有紀,尾崎明仁, The Inference of Window Insulation and Interior Materials Providing Moisture Control on Indoor Hygrothermal Environment, Proc. of Asim2012 - The 1st Asia Conference of International Building Performance Simulation Association, 7, ID0060, 2012.11.
64. Yuki Sato, Akihito Ozaki, Tetsumi Nakamura, Yoshihiko Hayashi, Shigeki Ishiguro, Research on the reduction effect of the space heating load by latent heat storage interior building material
Examination by a model box experiment, a test house experiment, and a numerical simulation, Journal of Environmental Engineering (Japan), 10.3130/aije.77.651, 77, 678, 651-659, 2012.08, The phase-change characteristic of PCM and the influence of phase-change thermal storage on indoor thermal environment and heatingload were examined with the aim of effective utilization of solar heat by model experiments, outdoor experiments and numerical simulation. The main results obtained are as follows. In the model experiment, the basic data on PCM amount and construction area to keep the room temperature constant are obtained. In the outdoor experiments, the heating load during the night was reduced by up to 9.6% in sunny day by apparent effects of heat storage on PCM constructed in the floor of test house. In addition, the horizontal distribution of room temperature was moderated by relieving cold drafts from windows with temperature rise of the PCM constructed floor. It was confirmed that the simulation software 'THERB for HAM' can accurately calculate the actual indoor thermal environments through the comparison with experimental results. Sensitive analyses on heating load for a single-family house utilizing THERB and multiple linear regression analyses with calculation results clarified that the construction area of PCM, the temperature difference between melting point of PCM and heating preset temperature, the heat loss coefficient of buildings, the constructed amount of PCM have a profound effect in sequence on the heating load and then those contributory factors are crucially important in the development of PCM building materials and solar heat utilization houses..
65. 佐藤有紀,尾崎明仁,中村哲己,林 禎彦,石黒成紀, Development and Performance Evaluation of Interior Material Fully-Featured Latent Heat Storage Designed at Energy Conservation, Proc. of the 5th International Building Physics Conference, 697-703, 2012.05.
66. 李 明香,尾崎明仁, Prediction of Sensory Index Based on Hygrothermal Balance of Human Body in Combination with Heat and Moisture Transfer and Airflow of Whole Buildings, Proc. of the 5th International Building Physics Conference, 649-656, 2012.05.
67. 尾崎明仁,李 明香,隈 裕子, Numerical Simulation on Hygrothermal Environment of Whole Buildings Taking into Account Complete HAM Features, Proc. of the 12th International Building Performance Simulation Association Conference, 2156-2163, Building Simulation 2011, 2011.12.
68. M. Lee, A. Ozaki, Numerical simulation on hygrothermal environment of whole buildings based on detailed building physics on heat and moisture transfer and airflow, 7th International Symposium on Heating, Ventilating and Air Conditioning, ISHVAC 2011 7th International Symposium on Heating, Ventilating and Air Conditioning - Proceedings of ISHVAC 2011, 1087-1093, 2011.12, Many simulation software to predict thermal environment of buildings, such as temperature, humidity, heating and cooling load of building spaces, have been developed according to the development concept such as calculation accuracy, calculation speed, user-friendliness. However, most of them do not take into account moisture transfer in wall assemblies. Humidity calculation in most software is simply affected by ventilation and focuses on just the building spaces. A Heat, Air and Moisture (HAM) simulation software called THERB has been developed for the purpose of estimating the hygrothermal environment within buildings. This software has complete HAM features including principles of moisture transfer within walls. In this paper, the prominent features of the THERB are highlighted. Then the accuracy is verified through the comparison of calculation and monitoring results of a residential building. The difference of hygrothermal environment is clarified based whether or not moisture sorption and desorption of walls are incorporated. Furthermore, Sensitive analysis utilizing THERB is performed with the differences of calculation models on heat transfer and incident solar radiation into indoor surfaces..
69. 李 明香,尾崎明仁, Numerical Simulation on Hygrothermal Environment of Whole Buildings Based on Detailed Building Physics on Heat and Moisture Transfer and Airflow, Proc. of the 7th International Symposium on Heating, Ventilation and Air Conditioning, 1128-1134, 2011.11.
70. Yupeng Wang, Hiroatsu Fukuda, Akihito Ozaki, Simulation study on the effect of insulation on interior structural parts of super high-rise residences, Journal of Environmental Engineering, 10.3130/aije.76.999, 76, 669, 999-1008, 2011.11, We examined the impact of air-conditioning loads (hereinafter referred to as AC loads) on the interior structural parts and the AC-usage patternsof super-high-rise residences. We considered different building orientations, structures, and insulation methods. We used the dynamic simulation software THERB (simulation of the thermal environment of residential buildings). It can estimate the temperature, humidity, sensible temperature, and heating/cooling load for multiple buildings. Super-high-rise residences have more structural components such as pillars and beams than do ordinary apartment buildings. The skeleton is generally made of concrete and steel, which have high thermal-storage capacities. The thermal-storage capacity of super-high-rise residences is considered to have a larger impact on the AC load and thermal comfort than that of ordinary residences. We show that the AC load of super-high-rise units would be reduced by installing insulation on the surfaces of interior walls that are not usually insulated in Japan..
71. Yupeng Wang, Hiroatsu Fukuda, Yuko Kuma, Akihito Ozaki, Study of air-conditioning load
Comparison of steel and RC residence units, Journal of Asian Architecture and Building Engineering, 10.3130/jaabe.9.571, 9, 2, 571-576, 2010.01, Recently, the fight against global warming is becoming increasingly important. Being major energy consumers, air-conditioning (AC) loads are gaining importance. Therefore, the effects of heat insulation methods and AC usage patterns on AC loads should be verified before a building is constructed. This paper examines the AC loads of two typical residential units of steel (S) and reinforced concrete (RC). To compare and analyze these cases, THERB, software for dynamic simulation of the thermal environment of residential buildings, is employed to simulate the loads. Three common patterns based on the lifestyle in Japan are applied in this study to show that different family makeup can lead to varying AC loads. Further, two RC units (exterior wall insulated on the inside/ outside) and one S unit (exterior wall insulated on the inside) are studied. The results reveal that the high heat capacity of concrete influences the living environment and causes differences between the RC and S units. The AC load of an RC unit with an exterior wall that is insulated on the inside is lower than that of a unit with an exterior wall that is insulated on the outside and is almost equal to that of the S unit..
72. 中野誠司,尾崎明仁,渡邊俊行, Efficiency of Solar Radiation on Heating Energy Conservation of Residential Buildings, Proc. of the 11th International Building Performance Simulation Association Conference, 2085-2091, Building Simulation 2009, 2009.07.
73. 尾崎明仁,佐藤有紀,李 明香,松田千怜, The Effect of PCM Interior Finishing Material with Moisture Sorption and Desorption Characteristics on Hygrothermal Control of Rooms, Proc. of the 11th International Building Performance Simulation Association Conference, 1822-1829, Building Simulation 2009, 2009.07.
74. 尾崎明仁,李 明香,小笹治美, Influence of the Thermal Bridge through Window Frame on Hygrothermal Conditions of Building Envelopes, Proc. of the 11th International ROOMVENT Conference, 1112-1118, 2009.05.
75. Akihito Ozaki, Yuki Satou, Myonghyang Lee, Chisato Matsuda, The effect of PCM interior finishing material with moisture sorption and desorption characteristics on hygrothermal control of rooms, 11th International IBPSA Conference - Building Simulation 2009, BS 2009 IBPSA 2009 - International Building Performance Simulation Association 2009, 1822-1829, 2009.04, In this paper, the hygrothermal controll material, the interior finishing material with moisture sorption and desorption characteristics containing PCM (Phase Change Material utilizing latent heat), is developed to provide the function of constant temperature and humidity in buildings. The model experiments and the numerical simulation have examined the influence of the hygrothermal controll materials on the indoor environment. The simulation software "THERB" which has complete HAM features (heat and moisture transfer and airflow) including principles of moisture transfer within walls is used and its accuracy is also verified through the comparison of the calculations and the experiments..
76. 副島正成,渡邊俊行,尾崎明仁, Efficiency of Energy Conservation Methods on Space Conditioning Load of Residential Buildings, Proc. of the 29th AIVC Conference - Advanced Building Ventilation and Environmental Technology for Addressing Climate Change Issues, Vol.2, 227-232, 2008.10.
77. 尾崎明仁,小笹治美,隈 裕子, Potential Influence of Moisture Sorption and Desorption of Walls on Space Conditioning Load of Residential Buildings, Proc. of the 29th AIVC Conference - Advanced Building Ventilation and Environmental Technology for Addressing Climate Change Issues, Vol.1, 287-292, 2008.10.
78. Hiroto Takaguchi, Takuya Hirose, Akihito Ozaki, Diverse lifestyles and energy comsumption of single-person household, AIJ Journal of Technology and Design, 10.3130/aijt.14.521, 14, 28, 521-524, 2008.10, We did the survey of the questionnaire of the lifestyle realities of the single-person household. Through the result, we have devised a lifestyle model of the household. This model is composed by the use frequency of home electric appliances and the daily action style. This model will become an effective model for the energy conservation adoption in thinking about the diversification of the home form in the future..
79. Yuko Kuma, Akihito Ozaki, Harumi Ozasa, Hiroatsu Fukuda, Influence of moisture sorption and desorption of walls onspace conditioning load
Factorial analysis of latent heat load, Journal of Environmental Engineering, 10.3130/aije.73.1171, 73, 632, 1171-1178, 2008.10, In this paper, the influence of moisture soiption and dcsorption of walls on space conditioning load is exaluated by dynamic simulation based on detailed building physics taking account of heat and moisture transfer and aiifloo of whole huildings. Then sensitive analysis is performed with a number of factors, such as preset temperature and humidity of space condiliomng, ventilation amount, property of inferior materials and so on, which influence indoor humidity. Eleven factors that affect indoor humidity are detined with the extent of the influence by the multiple regression analysis on the basis offhe sensitive analysis. It is clarified that the moisture sorption and desorpf ion of walls are influence both heating and cooling load at a rate over 10 percent and water vapoui pcirncance and moisture capacity of interior finish are the significant factor on the moisture solption and desorption..
80. Y. Wang, H. Fukuda, A. Ozaki, Y. Kuma, A study on AC load impact by AC pattern and heat insulation method of super high-rise residences, 6th International Conference on Indoor Air Quality, Ventilation and Energy Conservation in Buildings: Sustainable Built Environment, IAQVEC 2007 IAQVEC 2007 Proceedings - 6th International Conference on Indoor Air Quality, Ventilation and Energy Conservation in Buildings Sustainable Built Environment, 813-818, 2007.12, This paper examines air-conditioning loads by several air-conditioning patterns and heat methods of a super high-rise residence by using the dynamic simulation software "THERB" (the simulation software of the thermal environment of residential buildings) which can estimate temperature, humidity, sensible temperature, and heating/cooling load for multiple zones of buildings. As high-rise residences, the ratio that the structural skeleton dominates a floor area is bigger than that of ordinary residences, and its skeleton is used concrete generally. Heat capacity has a considerable impact on air-conditioning load of high-rise residences. Meanwhile, aspects of air-conditioning style, heat insulation style, structural form and building direction affect to air-conditioning load of high-rise residences significantly. Recently, high-rise residences are to be more and more important factor in our life with its rapid development. It is respected that most people will chose high-rise residences, because of its popularization. Therefore, we must reduce energy consumption for keeping environment load reduction in high-rise residences. Based on above mentioned, heat environment impact on high-rise residences will become an important issue in our society..
81. Akihiro Mitsumoto, Hiroatsu Fukuda, Yupeng Wang, Akihito Ozaki, Yuko Kuma, Study on structure heat capacity of high-rise residences (part 1) comparison with or without insulation, 16th IASTED International Conference on Applied Simulation and Modelling, ASM 2007 Proceedings of the 16th IASTED International Conference on Applied Simulation and Modelling, ASM 2007, 115-118, 2007.12, Here we examined Air-Conditioning loads (hereinafter referred to as AC loads) impact in several deferent cases of insulation methods in interior of super high-rise residences by using the dynamic simulation software "THERB"(the simulation software of Thermal Environment of Residential Buildings), which can estimate temperature, humidity, sensible temperature and heating/cooling load for multiple zones of buildings. The Proportion that structural frames, such as columns and beams of super high-rise residences, is larger than that of ordinary residences, and the skeleton is generally made of concrete and steel which have high heat storage capacity. Therefore the heat storage capacity of structure of super high-rise residences is considered to have larger effect on AC load than that of ordinary residences. So we consider that the AC load of super high-rise unit would be cut down by putting insulation on surface of interior walls, floors and ceilings on which usually insulation isn't put in Japanese buildings. Recently, high-rise residences are more and more important in our life with its rapid development in Japan. Therefore, reduction of energy consumption in high-rise residences is very important to reduce total environmental loads in Japan..
82. Yupeng Wang, Hiroatsu Fukuda, Akihiro Mitsumoto, Akihito Ozaki, Yuko Kuma, Study on structure heat capacity of high-rise residences (part 2) comparison by insulation methods, 16th IASTED International Conference on Applied Simulation and Modelling, ASM 2007 Proceedings of the 16th IASTED International Conference on Applied Simulation and Modelling, ASM 2007, 209-212, 2007.12, This paper follows the paper of Part 1. Here we examined Air-Conditioning loads (hereinafter referred to as AC loads) impact in several deferent cases of insulation methods in interior of super high-rise residences by using the dynamic simulation software "THERB"(the simulation software of Thermal Environment of Residential Buildings), which can estimate temperature, humidity, sensible temperature and heating/cooling load for multiple zones of buildings. The Proportion that structural frames, such as columns and beams of super high-rise residences, is larger than that of ordinary residences, and the skeleton is generally made of concrete and steel which have high heat storage capacity. Therefore the heat storage capacity of structure of super high-rise residences is considered to have larger effect on AC load than that of ordinary residences. So we consider that the AC load of super high-rise unit would be cut down by putting insulation on surface of interior walls, floors and ceilings on which usually insulation isn't put in Japanese buildings. Recently, high-rise residences are more and more important in our life with its rapid development in Japan. Therefore, reduction of energy consumption in high-rise residences is very important to reduce total environmental loads in Japan..
83. Yu Peng Wang, Hiroatsu Fukuda, Akihito Ozaki, Yuko Kuma, Analysis of energy load for a unit of super high-rise residences by dynamic simulation, Huanan Ligong Daxue Xuebao/Journal of South China University of Technology (Natural Science), 35, SUPPL., 223-226, 2007.10, This paper investigates the impact of structural skeleton on heat load of super high-rise residences with different air-conditioning patterns, heat insulation styles, building directions and glazing structures by using the dynamic simulation software 'THERB'(the simulation software of the thermal environment of residential buildings) which can estimate the temperature, humidity, sensible temperature and heating/cooling load for multiple zones of buildings. In high-rise residences, the ratio that the structural skeleton dominates a floor area is bigger than that in ordinary residences, and the skeleton is generally made up of concrete, so the heat capacity has a considerable impact on heat load of high-rise residences. Meanwhile, the aspects of air-conditioning style, heat insulation style, structural form and building direction affect the heat load of high-rise residences significantly..
84. 綾垣伸康,尾崎明仁,高口洋人,黒木 洋,渡邊俊行, Prediction of Energy Efficiency and Thermal Environment of Residential Buildings Utilizing PEFC-CGS Combined Floor Heating System, Proc. of the 10th International Building Performance Simulation Association Conference, 546-553, Building Simulation 2007, 2007.09.
85. 隈 裕子,、福田展淳,尾崎明仁, Performance Evaluation of Residences by Dynamic Simulation - Heat Load Based on Changing the Location, Plan and Specification of Residences, Journal of Asian Architecture and Building Engineering, Vol.6, No.1, 183-188, 2007.05.
86. 尾崎明仁,香川治美, Sensitive Analysis for Hygrothermal Environment of Residential Buildings during Heating, Journal of Harbin Institute of Technology, Vol.14, 196-200, 2007.01.
87. Akihito Ozaki, Harumi Kagawa, Sensitive analysis for hygrothermal environment of residential buildings during heating, Journal of Harbin Institute of Technology (New Series), 14, SUPPL. 2, 196-200, 2007.01, Dynamic simulation software based upon detailed building physics called THERB for HAM is used to predict hygrothermal environment of whole building. The accuracy of THERB is verified through the comparison of monitored and calculated values of temperature and humidity of the actual residential buildings. Then sensitive analysis utilizing THERB is performed with a number of factors, such as property, area and thickness of interior materials and so on, which influence indoor humidity, especially excessive dryness during heating. Eleven factors that affect indoor humidity are defined with the extent of the influence by the multiple regression analysis on the basis of the sensitive analysis. It is clarified that the THERB can accurately predict the hygrothermal environment of buildings and the extreme sensitive factors influencing indoor humidity are the moisture generation in rooms, outdoor temperature and humidity, the preset heating temperature, water vapour permeance of interior finish and the area of adsorption and desorption materials..
88. Huibo Zhang, Hiroshi Yoshino, Shuzo Murakami, Kazuaki Bogaki, Toshihiko Tanaka, Hirofumi Hayama, Shin Ichi Akabayashi, Takashi Inoue, Akihiko Iio, Shuichi Hokoi, Akihito Ozaki, Keiko Abe, Investigation of actual humidity conditions in houses and evaluation of indoor environment by fungal index, 6th International Conference on Indoor Air Quality, Ventilation and Energy Conservation in Buildings: Sustainable Built Environment, IAQVEC 2007 IAQVEC 2007 Proceedings - 6th International Conference on Indoor Air Quality, Ventilation and Energy Conservation in Buildings Sustainable Built Environment, 289-294, 2007.01, The characteristics of climate in Japan are hot and humid in summer, with cold and dry winter. For this reason, mold growing in rooms is common during summer period. On the other hand, in winter, due to space heating, indoor environment is over-dry as a result of low humidity. This situation is particularly distinctive in the well-insulated and air-tightened houses. The aim of this study was to understand the current indoor humidity environmental conditions by the means of long-term measurement data for obtaining the fundamental information to evaluate the measures to mitigate the dry or humid indoor environment. In addition, the conditions of fungal contamination influenced by indoor environment were predicted. A detailed long-term field measurement program on energy consumption and indoor thermal environment was carried out in 2003, for 80 dwellings (including detached houses and apartments) in six regions of Japan. The data obtained from the field measurement were analyzed and the results based on indoor humidity distribution were reported in this paper..
89. Yuko Kuma, Hiroatsu Fukuda, Akihito Ozaki, Performance Evaluation of Residences by Dynamic Simulation
Heat Load Based on Changing the Location, Plan and Specification of Residences, Journal of Asian Architecture and Building Engineering, 10.3130/jaabe.6.183, 6, 1, 183-188, 2007.01, The Japanese residential energy saving standard for new house generation was modified in 1999, in which “specification standards” were provided as decision criteria for designers. However, there are several methods for lowering the energy consumption of houses which are not evaluated by these standards. In this paper, we predict the change in heating and cooling load by difference of location, planning and specification of a model house, which are not evaluated by “the specification standards”. We then examine the effectiveness of passive energy methods which are also not considered by the standard..
90. 尾崎明仁,香川治美, Simulation Software to Describe the Hygrothermal Environment of Whole Buildings Based on Detailed Physical Models, Proc. of the 7th International Conference of System Simulation in Buildings, 24, P03, 2006.12.
91. Yasuto Takuma, Hiroyuki Inoue, Futoshi Nagano, Akihito Ozaki, Hiroto Takaguchi, Toshiyuki Watanabe, Detailed research for energy consumption of residences in Northern Kyushu, Japan, Energy and Buildings, 10.1016/j.enbuild.2006.04.010, 38, 11, 1349-1355, 2006.11, Energy consumption in residential sector has been increasing year by year since 1965. To improve this situation, it is necessary to reconsider the traditional energy supply systems. Distributed power source systems, such as photovoltaic (PV) system and micro co-generation system, are considered as solutions to current residential energy problems. In order to utilize these systems effectively, understanding detailed energy consumption of residences is required. The purpose of this research is to clarify detailed energy consumption; seasonal and annual energy consumption classified by uses, the effect of energy-saving apparatus and heating demand of residences located in the north of Kyushu, Japan. Major results are as follows: (1) energy consumption for hot water supply is larger than ones for lighting, air-conditioning and cooking among most houses, in the north part of Kyushu, (2) PV system is quite effective to save energy of residential buildings, and (3) Heat demand and electric power demand of residences are clarified by detailed measurement for installing individual dispersed power source system, some houses show high thermoelectricity ratio enough to move micro co-generation system effectively, even at present..
92. 尾崎明仁,辻丸達憲, Prediction of Hygrothermal Environment of Buildings Based upon Combined Simulation of Heat and Moisture Transfer and Airflow, Journal of the International Building Performance Simulation Association, Vol.16, No.2, 30-37, 2006.10.
93. 宅間康人,井上博之,永野 太,尾崎明仁,高口洋人,渡邊俊行, Detailed Research for Energy Consumption of Residences in Northern Kyushu, Japan, Journal of Energy and Buildings, Vol.38, 1349-1355, 2006.09.
94. 尾崎明仁,長谷川惣一, Analysis on the Hygrothermal Environment of Crawlspaces to Prevent Moisture Damage Based upon Combined Simulation of heat, Air and Moisture Transfer, Proc. of the 2005 World Sustainable Building Conference, 1517-1524, 2005.09.
95. 尾崎明仁,辻丸達憲, Prediction of Hygrothermal Environment of Buildings Based upon Combined Simulation of Heat and Moisture Transfer and Airflow, Proc. of the 9th International Building Performance Simulation Association Conference, Vol.II, 899-906, Building Simulation 2005, 2005.08.
96. 細川隆行,林 徹夫,尾崎明仁,小島昌一,野村幸司, Simplified Calculation Method for Moisture Movement on Wall Surfaces, Proc. of the 3rd International Workshop on Energy and Environment of Residential Buildings, 191-196, 2004.11.
97. 尾崎明仁,渡邊俊行,辻丸達憲, Combined Simulation of Heat and Air and Moisture on the Hygrothermal Environment of Building, Proc. of the 3rd International Workshop on Energy and Environment of Residential Buildings, 179-184, 2004.11.
98. 宅間康人,井上博之,尾崎明仁,渡邊俊行,高口洋人,Yu L.,永野 太, Detailed Research for Energy Consumption of Residences in Northern Kyushu, Japan, Proc. of the 3rd International Workshop on Energy and Environment of Residential Buildings, 110-115, 2004.11.
99. 尾崎明仁,渡邊俊行,高瀬秀芳, Simulation Software of the Hygrothermal Environment of Buildings Based on Detailed Thermodynamic Models, Proc. of eSim 2004 - The Canadian Conference on Building Energy Simulation, 45-54, 2004.06.
100. 隈 裕子,福田展淳,尾崎明仁, Evaluation of Building Thermal Environment by Dynamic Simulation - Part 1 Case studies of a clubhouse of Kitakyushu University, Proc. of the 5th International Symposium on Architectural Interchanges in Asia, 524-527, 2004.06.
101. 尾崎明仁, Systematic Analysis Model on Combined Heat and Water Transfer Using Water Potential Based on Thermodynamics, Journal of Thermal Envelope & Building Science, Vol.27, No.2, 95-122, 2003.10.
102. Akihito Ozaki, Systematic Analysis Model on Combined Heat and Water Transfer Using Water Potential Based on Thermodynamics, Journal of Thermal Envelope and Building Science, 10.1177/1097196303032806, 27, 2, 95-122, 2003.10, A thermodynamic energy "water potential" based on the principles of chemical potential of an element of mixed gas is defined as the driving force of gaseous phase water transfer. Adhesive power or "capillary action" and a portion of the water potential, is confirmed as the driving force of liquid phase water transfer. A numerical model of combined heat and water transfer using the water potential is introduced and influences of forces such as gravity and pressure on water transfer are incorporated from the viewpoint of thermodynamics. A way to estimate diffusivities of gaseous and liquid phase water through porous materials and the thermodynamic relations between such diffusivities and the potential are also shown. Accuracy of the numerical model is demonstrated through a comparison between calculation and experiment for different temperature gradients and water content in a porous material..
103. 尾崎明仁, Systematic Derivation of the New Potential Model on Combined Heat and Water Transfer Based on Thermodynamics, Journal of Asian Architecture and Building Engineering, Vol.2, No.1, 17-24, 2003.05.
104. Akihito Ozaki, Systematic Derivation of the New Potential Model on Combined Heat and Water Transfer Based on Thermodynamics, Journal of Asian Architecture and Building Engineering, 10.3130/jaabe.2.17, 2, 1, 17-24, 2003.01, A thermodynamic energy “water potential” based on the principles of chemical potential of an element of mixed gas is defined as the driving force of gaseous phase water transfer. Adhesive power or “capillary action” and a portion of the water potential, is confirmed as the driving force of liquid phase water transfer. A numerical model of combined heat and water transfer using the water potential is introduced and influences of forces such as gravity and pressure on water transfer are incorporated from the viewpoint of thermodynamics. A way to estimate diffusivities of gaseous and liquid phase water through porous materials and the thermodynamic relations between such diffusivities and the potential are also shown..
105. Maoyu Ran,渡邊俊行,尾崎明仁,Yun Cai, Theoretical Basis of Humidity Controlling Index of Materials in Closed Space, Proc. of the 2nd International Workshop on Energy and Environmental of Residential Buildings in China, 251-255, 2002.10.
106. 田上美佐子,渡邊俊行,尾崎明仁,岩岡重樹, Simulation for the Development of High Insulated and Airtight Houses in Japan, Proc. of eSim 2002 - The Canadian Conference on Building Energy Simulation, 128-134, 2002.09.
107. 高瀬秀芳,渡邊俊行,尾崎明仁,山下秀一, Simulation of the Maximum Heating and Cooling Loads for an Atrium Space, Proc. of eSim 2002 - The Canadian Conference on Building Energy Simulation, 120-127, 2002.09.
108. 高瀬秀芳,渡邊俊行,林 徹夫,尾崎明仁, Measurement and Simulation of the Thermal Environment of a Low Energy House with Air-Circulation in Brick Walls, Proc. of eSim 2001 - The Canadian Conference on Building Energy Simulation, 212-219, 2001.06.
109. 尾崎明仁,渡邊俊行,岩岡重樹,高瀬秀芳, Simulation Software to Describe the Thermal Environment of Residential Buildings Based on Detailed Physical Models, Proc. of eSim 2001 - The Canadian Conference on Building Energy Simulation, 66-73, 2001.06.
110. 尾崎明仁,渡邊俊行,林 徹夫,龍 有二, Systematic Analysis on Combined Heat and Water Transfer through Porous Materials Based on Thermodynamic Energy, Journal of Energy and Buildings, Vol.33, No.4, 341-350, 2001.04.
111. Akihito Ozaki, Toshiyuki Watanabe, Tetsuo Hayashi, Yuji Ryu, Systematic analysis on combined heat and water transfer through porous materials based on thermodynamic energy, Energy and Buildings, 10.1016/S0378-7788(00)00116-X, 33, 4, 341-350, 2001.04, A new thermodynamic energy `water potential' based on the principles of chemical potential of an element of mixed gas is defined as the driving force of gaseous phase water flux. Adhesive power or `capillary action' and a portion of the water potential, is confirmed as the driving force of liquid phase water flux. A numerical model of combined heat and water transfer using the water potential is introduced and influences of forces, such as gravity and pressure on water flux are incorporated from the viewpoint of thermodynamics. A way to estimate diffusivities of gaseous and liquid phase water through porous materials is also shown. Accuracy of the numerical model is demonstrated through a comparison between calculation and experiment for different temperature gradients and water content in a porous material..
112. 尾崎明仁,渡邊俊行,林 徹夫,龍 有二, Analysis on Coupled Heat and Water Transfer through Porous Materials by Thermodynamic Energy, Proc. of the 8th International Building Performance Simulation Association Conference, 285-292, Building Simulation 1999, 1999.09.
113. 尾崎明仁, Analytical Theory on Coupled Heat and Water Transfer through Porous Materials, Proc. of the 8th international Conference on Indoor Air Quality and Climate, Vol.1, 738-743, 1999.08.
114. 小野公平,尾崎明仁,須貝 高, Cooling Load Reduction by Cold Ground Heat through Rock Bed in Temperate Climate Residences, Proc. of Renewable and Advanced Energy Systems for the 21st Century, 16, RAES99-7671, 1999.04.
115. 小野公平,尾崎明仁,須貝 高,森田 大, Assessment of Optimum Window Glazing in Temperate Climate in Terms of Solar Air Temperature, Proc. of International Thermal Energy and Environment Congress, Vol.2, 504-509, 1997.06.
116. 小野公平,尾崎明仁,須貝 高,神品恭二, Optimum Window Glazing in Cold and Mild Climate of Japan - Assessment in Terms of Solar Air Temperature, Proc. of the 14th International Conference on Passive and Low Energy Architecture, Vol.3, 171-176, 1997.01.
117. 尾崎明仁,須貝 高,渡邊俊行,神品恭二,小野公平, Analysis of Draft Quantity through Ventilated Air Space, Proc. of the 14th International Conference on Passive and Low Energy Architecture, Vol.2, 33-38, 1997.01.
118. 小野公平,尾崎明仁,須貝 高,森田 大, Heat Gain and Loss through Kinds of Window Glazing in Temperate Climate, Proc. of Healthy Build¬ings ’95 an International Confer¬ence on Healthy Buildings in Mild Climate, 317-322, 1995.07.
119. 尾崎明仁,須貝 高,石田 卓,渡邊俊行,龍 有二,赤司泰義, Study on Prevention of Moisture Injury of Exterior Walls in the Hot-Humid Season, Proc. of Indoor Air Quality, Ventilation and Energy Conservation in Buildings, 575-582, 1995.05.
120. 小野公平,尾崎明仁,須貝 高,森田 大, Effect of Window Glass on Room Thermal Environment and Air Conditioning Load, Proc. of Indoor Air Quality, Ventilation and Energy Conservation in Buildings, 515-522, 1995.05.
121. 尾崎明仁,須貝 高,渡邊俊行,龍 有二,赤司泰義,石田 卓, Analysis of Temperature and Moisture Fluctuation of Exterior Walls by Numerical Calculation, Selected Papers of International Symposium ’93 on Design of Amenity, 197-205, 1993.10.
122. 石田 卓,須貝 高,尾崎明仁, Study on Alleviation of Cold Drafts through Windows, Selected Papers of International Symposium ’93 on Design of Amenity, 192-196, 1993.10.
123. 石田 卓,須貝 高,神品恭二,尾崎明仁, Experimental Studies of the Highly Heat Insulated House Using Heat Insulating Panels, Proc. of International Conference on Human-Environment System, 319-322, 1991.12.
124. 尾崎明仁,須貝 高,神品恭二, Experimental Studies of the Roof Heat Insulation for Wooden House, Proc. of International Conference on Human-Environment System, 315-318, 1991.12.
125. 須貝 高,神品恭二,尾崎明仁, The Effect of Window on Room Thermal Environment, Proc. of International Conference on Human-Environment System, 303-306, 1991.12.
126. 尾崎明仁,渡邊俊行,須貝 高, A Simplified Calculation Method of Seasonal Air-Conditioning Requirements for Residential Buildings, Proc. of the International CIB W67 Symposium on Energy, Moisture and Climate in Buildings, 6, III 14, 1990.09.
127. 浦野良美,渡邊俊行,林 徹夫,龍 有二,尾崎明仁,吉竹裕二, Evaporative and Radiative Cooling of Houses in Seasonally Hot-Humid Area, Proc. of the International Mediterranean Congress on Solar and Other New-Renewable Resources, 159-173, 1988.11.
128. 浦野良美,渡邊俊行,林 徹夫,龍 有二,塩月義隆,尾崎明仁, Improvement in Thermal Performance of Outer Insulated Walls Using Water Evaporation and Selective Radiation, Proc. of the 1987 ASHRAE Far East Conference on Air-Conditioning in Hot Climates, 37-55, 1987.09.