Language：English   Publishing type：Research paper (scientific journal)  

Molecular Number Flux Detection using Oxygen Sensitive Luminophore

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Dual-layer PSP/TSP (DL-PTSP) technique is a method to compensate for the temperature sensitivity of pressure-sensitive paint (PSP) by composite measurement of pressure and temperature, which is based on the combination of PSP and temperature-sensitive paint (TSP) technique. Applying lifetime-based calibration to DL-PTSP enables simultaneous measurement of pressure and temperature by DL-PTSP with a single-camera equipment if the lifetime of PSP luminophore is very different from that of TSP luminophore. However, nonzero thickness of intermediate paint layers of DL-PTSP, separating the upper PSP layer and the lower TSP layer physically, may cause temperature difference between the PSP layer and the TSP layer, and the delay of time response of temperature measurement by the TSP layer. Although the intermediate layers of DL-PTSP cannot be eliminated completely, it is desirable to decrease their thickness, that is, it is important to clarify optimum thickness of the intermediate layers of DL-PTSP. In this study, the relation between the thickness of the intermediate layers and the properties of DL-PTSP with the lifetime-based calibration method, such as the sensitivity of pressure and temperature and the time response of temperature measurement, are examined. It is clarified that the independence of pressure measurement and temperature measurement are kept for DL-PTSP by using the lifetime-based calibration method, when the total thickness of the intermediate layers is as thin as 12µm. The time delay of the temperature measured by the TSP layer from that of the PSP layer is as small as milliseconds if the thickness of the intermediate layers is 12µm.

Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： doi.org/10.1115/AJKFluids2019-5175

Language：English   Publishing type：Research paper (international conference proceedings)  

There are still very few applications of pressure sensitive paint (PSP) for measurement of nonstationary pressure distribution of internal flows in mechanical engineering fields. Application method of PSP taking the luminescent images of PSP through the transparent solid body (e.g. shroud wall of turbomachinery) and translucent PSP layer enables to apply PSP to the measurement of internal flows. However, this method results in low S/N, because PSP without opaque white basecoat has low luminescent intensity and overlaying image inside the body through the transparent material and PSP layer cause significant error in taking the luminescent image of PSP. To solve the problem, we have developed the application method of PSP by using an opaque, oxygen-permeable overcoat layer having porous structure made of nanoparticles of boron nitride (BN). This overcoat enables to increase the S/N of PSP in the transparent mode, which is needed for measurement of internal flows. In this study, we apply silica nanoparticle PSP having fast time response, because the pressure distribution on a shroud wall of turbomachinery is intrinsically unsteady. To analyze the effect of the opaque overcoat on the pressure sensitivity and the time response of the PSP, we have compared the properties of the PSP with the overcoat and those of the PSP without the overcoat. As a result, it is clarified that the opaque overcoat of BN nanoparticle does not reduce the pressure sensitivity and the time response of the fast-response PSP, which can detect periodical pressure change of the order of 100Pa and lower than 3 kHz. We have applied the fast-response PSP with the overcoat to the pressure measurement of an inner wall of a test axial compressor with the blade-passing frequency of 520Hz, and the qualitative images of the pressure distribution are obtained. We consider that the most significant source of the error in the pressure measurement is the temperature-dependence of the PSP. Therefore, the simultaneous measurement of temperature distribution is needed to increase the accuracy of the pressure measurement using the PSP.

Language：Japanese   Publishing type：Research paper (other academic)  

Development of Pressure Distribution Measurement Method on Inner Wall of Turbofan Using Pressure Sensitive Paint
Kazuya HANDA, Keishiro TAKEDA, Tomohiro IMAZEKI, Kil-ju MOON, Hideo MORI
Journal of the Vizualization Society of Japan, Vol. 37, Suppl. 2, OS1-1-5

Language：English   Publishing type：Research paper (international conference proceedings)  

The measurement method using PSP (Pressure Sensitive Paint) is useful to measure the two-dimensional pressure distributions on solid surfaces. However, PSP has not only pressure dependence but also temperature dependence. The error of temperature dependence becomes relatively large when measuring low-gauge pressure condition because PSP is absolute pressure sensor. To solve the problem, we designed DL-PTSP (Dual layer PSP/TSP) which stack up TSP (Temperature Sensitive Paint) and PSP layers, to apply TSP to temperature compensation of PSP. In the previous studies, we showed the temperature compensation effect of DL-PTSP with the intensity-based method at non-uniform temperature field in low-gauge pressure condition. However, the intensity-based method using DL-PTSP requires two cameras for simultaneous measurement of temperature and pressure because it requires two optical filters to separate the luminescence of PSP and TSP. In this study, we propose the method of simultaneous measurement using DL-PTSP with lifetime-based method. Big advantage of the method is to enable simultaneous measurement of pressure and temperature with a single camera, because the different lifetime of PSP and TSP enables to separate the luminescence of PSP and TSP without using two optical filters. In addition, DL-PTSP using lifetime-based method does not require wind off images, which may cause significant error of PSP with intensity-based method. At first, we show the dependence of the lifetime of mono-layer PSP and mono-layer TSP on the pressure and the temperature, to clarify the feasibility of the lifetime-based measurement method of PSP and TSP, and we propose the detailed method to separate the luminescence of them. Finally, we apply the lifetime-based method to DL-PTSP and suggest the possibility of temperature compensation of the DL-PTSP.

Language：Japanese   Publishing type：Research paper (other academic)  

Pressure/temperature simultaneous measurement method of dual layer PSP/TSP using lifetime based method
Kil-Ju Moon and Hideo Mori
Journal of the Vizualization Society of Japan, Vol. 37, Suppl. 1, F113

Language：Japanese   Publishing type：Research paper (other academic)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publishing type：Research paper (other academic)  

Language：English   Publishing type：Research paper (international conference proceedings)  

We apply pressure sensitive paint (PSP) to quantitative analysis of pressure distribution and visualization of shockwave structures on a sidewall in a supersonic flow passing through a turbine cascade. To compensate for the temperature dependence of PSP, we apply dual-layer PSP/TSP, the combination method of PSP and temperature sensitive paint (TSP) based on luminescent nanoparticles of ZnS-AgInS2 (ZAIS). Accuracy of the pressure measurement of the sidewall with non-uniform temperature distribution by the dual-layer PSP/TSP is examined in the supersonic wind tunnel tests, by comparing the pressure data obtained by the dual-layer PSP/TSP with those measured by pressure taps. The pressure distribution on the sidewall measured by the PSP component showed large error without temperature compensation, which is reduced effectively by the temperature compensation using the temperature distribution obtained by the TSP component. In addition, the shockwave structures visualized by the dual-layer PSP/TSP is compared with those obtained by the schlieren photograph. There is slight difference in shock angles and thickness between them, because the PSP visualizes the shockwave structure close to the sidewall while the schlieren photograph visualizes the shock structure in the mainstream.

Language：English   Publishing type：Research paper (other academic)  

Pressure sensitive paint (PSP) and temperature sensitive paint (TSP) are useful measurement tools in measurement of pressure and temperature distribution on surfaces in airflows, and application of PSP and TSP in relatively low speed flow fields is highly demanded. However, temperature dependence of PSP will be the factor of an error in the pressure measurement, and therefore the temperature compensation is needed to obtain highly precise pressure distribution. To solve this problem, we apply new combining method. This is made by stacking up a PSP layer and a TSP layer. PSP emission and TSP emission can be separated each other using optical filters. Using this combining method, temperature distribution obtained by the TSP can be used for the temperature compensation of the PSP. In this research we call this combining method as "dual-layer PSP/TSP". We clarify that the sensitivity of the dual-layer PSP/TSP in low-speed flow fields against pressure and temperature is comparable to that of mono-layer PSP or TSP, showing the feasibility of the dual-layer PSP/TSP for the measurement in low-speed flow fields with the gauge pressure below 1kPa and temperature in the range of 10-20°C (283-293K). We also clarify that, using dual-layer PSP/TSP method, the accuracy of pressure data obtained by PSP increases by compensation of temperature which is obtained by TSP.

DOI： 10.1115/AJK2011-11020

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (scientific journal)  

Pressure-sensitive paint (PSP) has the potential as a diagnostic tool for pressure measurement in high Knudsen number regime because it works as a so-called "molecular sensor". However, there are few reports concerning application of PSP to micro-devices, because conventional PSPs are too thick owing to polymer binders. In our previous work, we adopted the Langmuir-Blodgett (LB) technique to fabricate the pressure-sensitive molecular film (PSMF) using Pd(II) Mesoporphyrin IX (PdMP), which has pressure sensitivity only in the low pressure range (below 130 Pa). In this study, aiming for pressure measurement under an atmospheric pressure condition, we have constructed four samples of PSMFs composed of Pt(II) Mesoporphyrin IX (PtMP), Pt(II) Mesoporphyrin IX dimethylester (PtMPDME), Pt(II) Protoporphyrin IX (PtPP) and Cu(II) Mesoporphyrin IX dimethylester (CuMPDME) as luminescent molecules. The pressure sensitivity of those PSMFs was measured, and it was clarified that the pressure sensitivity of PSMF-PtMP is the highest among the four samples. Moreover, the temperature dependency of PSMF-PtMP was investigated, and we found that the temperature dependency of PSMF is dominated not by the oxygen diffusion in the layer, but by non-radiative deactivation process of excited luminescent molecules.

DOI： 10.1007/s00348-009-0694-6

Language：English   Publishing type：Research paper (scientific journal)  

The pressure-sensitive paint (PSP) is a very useful tool to measure pressure distributions on surfaces. In general, a measured pressure distribution by the paint shows good agreement with that by pressure taps. The paint is considered to represent the thermodynamic pressure. Recently, the paint has been adopted to rarefied gas flows and micro/nanoflows, i.e. high Knudsen number regime, and exhibited feasibility of pressure measurement in wide range of flows. In this study, we have discussed the physical meaning of luminescent intensity emitted from the paint through high Knudsen number regime measurements. It is known that a pressure tap shows good agreement with surface pressure and not with thermodynamic pressure in this regime, because of the temperature jump. High Knudsen number flow is required to be treated as a molecular flow; thus we discussed the PSP measurement mechanism by the molecular kinetic theory. The pressure profile of PSP was examined by a DSMC numerical result, and it was verified that PSP indicates the surface pressure. The temperature sensitivity was also investigated analytically in detail in continuum flow regime to discuss the suggestion that "PSP measures pressure, not density" [H. Bell, E.T. Schairer, L.A. Hand, R.D. Mehta, Surface pressure measurements using luminescent coatings, Annu. Rev. Fluid Mech. 33 (2001) 155-206]. From these analyses, however, we suggest that PSP measures a number flux of oxygen molecules toward the surface. The effect of a macroscopic flow against PSP in high Knudsen number flow is also discussed.

DOI： 10.1016/j.snb.2009.07.022

Language：English   Publishing type：Research paper (scientific journal)  

In late years, the necessity of high Knudsen number flows, such as highly rarefied gas flows with large mean free path and gaseous flows around nanodevices with small characteristic length have increased significantly, especially in fields of researches on space technology, surface science, fabrication of thin film for semi-conductor and so on. In this paper, we describe mainly the optical diagnostic techniques for the high Knudsen number flows, such as laser induced fluorescence (LIF), resonantly enhanced multiphoton ionization (REMPI) and pressure sensitive molecular film (PSMF), and our experimental results obtained by the use of the techniques, i.e., applications of LIF to visualization of flow field structures including complicated shock wave system and to a measurement of rotational temperature, establishment of a REMPI system and its application to detection of rotational nonequilibrium in highly rarefied gas flows, and development of the suitable PSMF for low density and micro-scale gas flows.

DOI： 10.1260/175683109789686691

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Molecular beams are powerful tools for diagnoses of solid surfaces and gas-surface interaction tests. Unfortunately, there are very few reports about experimental analysis of internal energy distribution (e.g. rotational energy) of molecular beams of diatomic or polyatomic molecules, because measurement of internal energy distribution is very difficult. Spectroscopic measurement techniques based on resonantly enhanced multiphoton ionization (REMPI) is very powerful for measurement in highly rarefied gas flows. In this study, the REMPI method is applied to measurement of rotational energy distribution of nitrogen molecular beams. The REMPI spectrum of the molecular beam indicates the rotational temperature higher than the translational temperature of 7.2 K estimated by assuming isentropic flows. The O and P branches of the REMPI spectrum correspond to the rotational temperature of 30 K, but the S branch of the spectrum deviates from that at 30 K. It seems to be because the non-equilibrium rotational energy distribution of the molecular beam deviates from the Boltzmann distribution.

Language：English   Publishing type：Research paper (scientific journal)  

The pressure-sensitive paint (PSP) has potential as a diagnostic tool for pressure measurement in the high Knudsen number regime because it works as a so-called "molecular sensor". However, there are few reports concerning application of the PSP to micro devices, because the conventional PSP is too thick owing to the use of polymer binder. In our previous work, we have adopted Langmuir-Blodgett (LB) technique to fabricate pressure sensitive molecular films (PSMFs) using Pd(II) Mesoporphyrin IX (PdMP). The PSMF based on PdMP has pressure sensitivity only at low pressure range (below 3kPa). In this study, we have constructed PSMF composed of Pt(II) Mesoporphyrin IX (PtMP) to be applied to pressure measurement near atmospheric pressure. The pressure sensitivity of PSMF based on PtMP has been tested, and it is clarified that the PSMF of PtMP has equivalent pressure sensitivity of polymer PSP. Moreover, we have applied PSMF to measurement of pressure distribution of micro-channel gas flow, showing its usefulness.

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (other academic)  

Pressure sensitive paint (PSP) technique is based on the interaction of oxygen molecules with luminescent molecules, and it seems suitable for analyses of high Knudsen number flows which require diagnostic tools in the molecular level. However, application of the PSP technique to micro-devices is still very difficult because of the thickness of PSP layers of the order of microns and the aggregation of luminescent molecules caused by the "painting" methods. To resolve the problems of ordinary PSPs mentioned above, we adopt the Langmuir-Blodgett (LB) method to fabricate pressure sensitive molecular films (PSMFs) having nanometer order thickness. The fundamental properties of the PSMFs such as the pressure sensitivity and the surface roughness are examined, to evaluate the feasibility of the PSMF technique for pressure measurement around micro-devices. A PSMF based on palladium (II) mesoporphyrin IX shows high pressure sensitivity in low pressure regime, while a PSMF based on platinum (II) mesoporphyrin IX is optimum for atmospheric pressure. It is also clarified that the PSMFs do not degrade the roughness of solid surfaces. The results indicate the feasibility of the PSMF technique for pressure measurement in high Knudsen number flows such as micro flows.

DOI： 10.1115/HT2007-32632

Language：English   Publishing type：Research paper (international conference proceedings)  

The Pressure Sensitive Paint (PSP) is very useful and easy way to obtain the pressure distribution on surfaces. Therefore the PSP has been adopted to various flow fields to obtain pressure distributions, showing good agreement with other methods, such as a pressure tap. Many kinds of flow fields have been used in the manufacturing process, like small scale, low pressure and/or high speed flows; for example, semiconductor manufacturing processes where a mean free path of gas molecules is large, and micro-/nano-systems where a characteristic length is small. Recently the PSP is applied to these high Knudsen number flows. Usually it is considered that the luminescent of the PSP represents the surface pressure, but it is not clear yet that this "pressure" means "static" or "total" pressure. The PSP is considered to be in the boundary layer, leading to the local equilibrium of oxygen molecular density between in the gas phase and in the PSP is achieved. This becomes a large problem especially in the high Knudsen number regime. The mechanism of the PSP has been mainly discussed focused on the luminescence intensity and the oxygen quenching of luminescent molecules. Here, in this study, we tried to relate the flux of oxygen molecules and the surface pressure to the luminescence intensity of the PSP, and clarify the limit of application from the molecular kinetics point of view. The main target of this problem was in the high Knudsen number and the high Mach number flow fields.

DOI： 10.1115/HT2007-32712

Language：English   Publishing type：Research paper (scientific journal)  

Experimental analyses of thermo-fluid phenomena of micro- and nano-flows with high Knudsen number need the measurement techniques based on interaction of atoms or molecules with photons. The pressure-sensitive paint (PSP) technique has potential as a diagnostic tool for pressure measurement in the high Knudsen number regime because it works as a so-called "molecular sensor". However, application of PSP to micro devices is very difficult because the conventional PSP is too thick owing to the use of polymer binder and does not have sufficient spatial resolution for pressure measurement of micro-flows. In this study, we have adopted the Langmuir-Blodgett (LB) technique to fabricate pressure sensitive molecular films (PSMFs) using Pd(II) Octaethylporphine (PdOEP) and Pd(II) Mesoporphyrin IX (PdMP) to resolve ordinary PSPs problems, and have tested these PSMFs to evaluate the feasibility of the pressure measurement around micro-devices. It is clarified that the PSMF composed of PdMP has higher sensitivity than that of PdOEP. Since it is also considered that the sensitivity of PSMFs can be increased by introducing arachidic acid (AA) as spacer molecules of LB films to prevent the aggregation of luminescent molecules, we have produced PSMFs with several molar ratio of PdMP to AA. At the most suitable ratio, the PSMF has high sensitivity in the low pressure region with high Knudsen number, even if the amount of the luminescent molecules in the PSMF layer is smaller than that in conventional PSPs. This result indicates that the PSMF is feasible to measure the pressure in high Knudsen number flows such as micro-flows.

DOI： 10.1007/s00348-007-0259-5

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (other academic)  

Gas flows in micro- and nano-systems having high Knudsen number must be treated as molecular flows, and experimental analyses of thermo-fluid phenomena in micro- and nano-systems need measurement techniques employing "molecular sensors". However, such measurement techniques are behind in development compared with molecular simulation techniques for numerical analyses. Pressure sensitive paint (PSP) technique is based on the interaction of oxygen molecules with luminescent molecules, and it seems suitable for analyses of high Knudsen number flows, which require diagnostic tools in the molecular level. In this study, we fabricate pressure sensitive molecular films (PSMF) with very small thickness based on the PSP technique and the Langmuir-Blodgett (LB) film technique. It is clarified that the PSMF composed of palladium (II) mesoporphyrin IX (PdMP) as a luminophore and arachidic acid as a buffer has comparable pressure sensitivity with conventional PSPs in low pressure regime with high Knudsen number, even if the amount of the luminescent molecules in the PSMF layer is much smaller than that in conventional PSPs. The results indicate the feasibility of PSMF technique for pressure measurement in high Knudsen number flows such as micro flows.

DOI： 10.1109/MHS.2006.320288

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (other academic)  

Aerospike nozzles have expected to be used for reusable space shuttles (single-stage-to-orbit: SSTO) to respond to growing demand for rocket launching at low cost. Unlike bell-type nozzles causing a big thrust loss due to over-expansion at low altitudes, aerospike nozzles expand combustion gas equilibrating with ambient pressure at any altitude, and the nominal expansion ratio is adjusted automatically to the suitable one. In this study, flow field structures in any cross sections around a linear-type aerospike nozzle are visualized and analyzed using NO-LIF. Since the flow field structures are affected mainly by the pressure ratio, the linear-type aerospike nozzle is set inside a vacuum chamber to carry out the experiments in the wide range of pressure ratios. A novel technique for measurement of surface pressure, the pressure sensitive paint (PSP) technique, is also applied successfully to measurement of the complicated pressure distribution on the spike surface. We have analysed flow fields of linear-type aerospike nozzles in detail by the two techniques for visualization and measurement, especially to demonstrate the effect of sidewalls to prevent the undesirable lateral expansion.

Language：English   Publishing type：Research paper (other academic)  

The pressure sensitive paint (PSP) technique has the capability to be applied to high Knudsen number flows, such as low density gas flows, micro-flows, and so on. In this study, to inspect the feasibility of PSP for measurement of pressure on a solid surface in the high Knudsen number flows, fundamental properties of three types of PSP [PdTFPP, PdOEP and PtTFPP bound by poly(TMSP)] are examined especially in the range of pressure below 130 Pa (about 1 Torr). The pressure sensitivity against nitrogen monoxide is also examined for the above PSPs, to develop a technique for the composite measurement of the flow field structure and the surface pressure, using NO-LIF and PSP, respectively. As an application of PSP to low density gas flows, we measure the pressure distribution on a jet-impinging solid surface using PdOEP/poly(TMSP) with very high pressure sensitivity.

DOI： 10.1063/1.1941715

Language：English   Publishing type：Research paper (other academic)  

An aerospike nozzle has been expected as a candidate for an engine of a reusable space shuttle to respond to growing demand for rocket-launching and its cost reduction. In this study, the flow field structures in any cross sections around clustered linear aerospike nozzles are visualized and analyzed, using laser induced fluorescence (LIF) of NO seeded in the carrier gas N₂. Since flow field structures are affected mainly by pressure ratio (P _s/P_a, P_s: the source pressure in a reservoir, P_a: the ambient pressure in the vacuum chamber), the clustered linear aerospike nozzle is set inside a vacuum chamber to carry out the experiments in the wide range of pressure ratios from 75 to 200. Flow fields are visualized in several cross-sections, demonstrating the complicated three-dimensional flow field structures. Pressure sensitive paint (PSP) of PtTFPP bound by poly-IBM-co-TFEM is also applied to measurement of the complicated pressure distribution on the spike surface, and to verification of contribution of a truncation plane to the thrust. Finally, to examine the effect of the sidewalls attached to the aerospike nozzle, the flow fields around the nozzle with the sidewalls are compared with those without sidewalls.

DOI： 10.1063/1.1941561

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (other academic)  

Experimental analyses of thermo-fluid phenomena of micro- and nano-flows with high Knudsen number need the measurement techniques based on interaction of atoms or molecules with photons. The pressure sensitive paint (PSP) technique has the capability to be applied to high Knudsen number flows, such as micro-flows and low density gas flows. In this study, to inspect the feasibility of PSP for measurement of pressure on a solid surface in high Knudsen number flows, fundamental properties of PSPs are examined especially in the range of pressure below 1 Torr. As an application of PSP to measurement in high Knudsen number conditions, the pressure distribution on a jet-impinging small solid surface is measured. However, application of the PSP technique to a micro-system is very difficult, because of large thickness of conventional PSPs. Therefore, we have adopted Langmuir-Blodgett (LB) method to fabricate a pressure sensitive molecular film (PSMF) applicable to pressure measurement around micro/nano devices. Finally, the dependence of luminescence intensity of PSP on the molecular number flux onto the solid surface is discussed, because molecular number flux is an important quantity to analyze the interaction between high Knudsen number flows and solid surfaces.

DOI： 10.1109/MHS.2005.1590002

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (other academic)  

Experimental analyses of thermo-fluid phenomena of micro- and nano-flows with high Knudsen number need the measurement techniques based on atoms or molecules, such as emission and absorption of photons. The pressure sensitive paint (PSP) technique has the capability to be applied to high Knudsen number flows, such as micro-flows and low density gas flows. In this study, to inspect the feasibility of PSP for measurement of pressure on a solid surface in high Knudsen number flows, fundamental properties of three types of PSP [PdTFPP, PdOEP and PtTFPP bound by poly(TMSP)] are examined especially in the range of pressure below 1 Torr. The pressure sensitivity against nitrogen monoxide is also examined for the above PSPs, to develop a technique for the composite measurement of flow field structure and surface pressure, using NO-LIF and PSP, respectively. As an application of PSP to measurement in high Knudsen number conditions, we measure the pressure distribution on a jet-impinging small solid surface using PdOEP/poly(TMSP) with very high sensitivity.

Language：English   Publishing type：Research paper (scientific journal)  

In the DLR-high vacuum plume test facility STG, experiments have been performed to study the expansion of supersonic plumes into vacuum with N ₂ as a test gas. The measured values were the Pitot pressure, the molecular number flux, the rotational temperature and the density. The last two quantities were measured by the 2+2 REMPI-technique with a stimulation wavelength of 283-284 nm (REMPI = resonance enhanced multi photon ionization). This method is also suitable to measure the absolute flow velocity by the ion time-of-flight (TOF) method, The apparatus for the combination of the REMPI and TOF technique is similar to that for the TOF experiments using electron beam bombardment, but a focused laser beam is used instead of an electron beam. The results of such laser measurements in highly rarefied plumes for several stagnation temperatures are presented with nitrogen as test gas. On-axis results fit well with the theoretical limiting velocity for perfect expansion; angular velocity profiles off-axis are discussed and compared to theory. This study is focused on the experimental procedure to measure the flow velocity of N₂ in rarefied plumes expanding from supersonic nozzles into vacuum.

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (other academic)  

A measurement technique of thermodynamic variables with high sensitivity is strongly demanded for analyses of highly rarefied gas flows. REMPI (Resonantly Enhanced Multiphoton Ionization) is a powerful optical tool because of its high sensitivity even in highly rarefied gas flows and ability to measure nonequilibrium among internal (translational, vibrational, and rotational) energy. In this study, to investigate fundamental properties of REMPI signal, the experimental apparatus of 2R N2-REMPI is constructed and the REMPI spectra are measured along the center line of a free molecular jet. A method of Boltzmann plot using the spectral lines of both O and P branches is proposed, determining electronic transition dipole moments in Hönl-London factors experimentally from the relative line strength of O and P branches. Then an effect of an experimental noise on a rotational temperature measured by the Boltzmann plot becomes smaller because the number of the lines used for the plot increases. By using the factors, simulated spectra agree well with experimental ones, suggesting feasibility of rotational temperature measurement by a spectral fitting.

DOI： 10.1063/1.1407662

Language：English   Publishing type：Research paper (scientific journal)  

In this study, the experimental system for 2R+2 N₂-REMPI (Resonantly Enhanced Multi-Photon Ionization) is established and applied to measurement of the rotational temperature in a supersonic free molecular nitrogen flow. In the 2R+2 N₂ REMPI technique, nitrogen molecules are ionized by two steps from the ground state to the resonance state by 2 photons and from the resonance state to the ionization state by 2 photons. The nitrogen ions are detected as a signal and its spectra depending on the wavelength of an irradiated laser beam are analyzed to measure the rotational temperature. The new Boltzmann plot method using spectral lines belonging to multiple branches is proposed to measure the rotational temperature more precisely, also showing the feasibility of the temperature measurement by the best fitting of the theoretical spectra to the experimental one. There appear the non-equilibrium phenomena in the highly rarefied gas flows, such as the translational and rotational non-equilibrium and the rotational non-equilibrium. The non-Boltzmann distribution (strong non-equilibrium) of the rotational mode in the ground state is found in the free molecular nitrogen flow using the REMPI technique.

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Event date： 2007.9

Presentation type：Oral presentation (general)  

Venue：Rome   Country：Italy  

Event date： 2007.7

Presentation type：Oral presentation (general)  

Venue：Vancouver   Country：Canada  

Event date： 2024.2

Language：English   Presentation type：Oral presentation (general)  

Venue：TKP Tokyo Station Conference Center (Tokyo)   Country：Japan  

Event date： 2023.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：近畿大学　東大阪キャンパス   Country：Japan  

Discussion on the Effect of Temperature Compensation for Imaging Measurement of Pressure Field by Using Dual-layer PSP/TSP with Lifetime-based Method

Event date： 2023.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：近畿大学　東大阪キャンパス   Country：Japan  

A Trial of Visualization of Dissolved Oxygen Distribution Under Cavitation

Event date： 2023.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：グランドパーク小樽   Country：Japan  

Simultaneous Measurement of Pressure and Temperature by Frequency-Domain Lifetime Imaging Technique
―Measurement Accuracy Comparison of a Single Layer of Luminous Paint and Dual-Layer of Luminous Paint―

Event date： 2023.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：グランドパーク小樽   Country：Japan  

Improvement of simultaneous measurement method of pressure and temperature fields by DL-PTSP by thinning of coating film

Event date： 2023.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：グランドパーク小樽   Country：Japan  

Development of PSP with Low Temperature Sensitivity for Unsteady Measurement of Back Flow Induced by Surging Using DL-PTSP

Event date： 2022.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：工学院大学   Country：Japan  

Event date： 2022.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：工学院大学   Country：Japan  

Event date： 2022.8

Language：English   Presentation type：Oral presentation (general)  

Venue：工学院大学（ハイブリッド開催）   Country：Japan  

Event date： 2021.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

寿命法に基づくDL-PTSP(Dual-layer PSP/TSP)の適用において，有限の膜厚さがもたらす層間の温度差は，DL-PTSPのPSP層が有する温度依存性の補正効果に影響をもたらす．そこでDL-PTSPによる圧力・温度場の同時計測精度向上を念頭に，PSPおよびTSP層や中間層の膜厚さがもたらす層間の温度差について検討するとともに，これらの層の構造がDL-PTSPの特性に及ぼす影響についても議論する．

Event date： 2021.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Shanghai Jiao Tong University (Online)   Country：China  

Temperature sensitivity of pressure-sensitive paint (PSP) has been one of the most serious problems for application of PSP. Dual-layer PSP/TSP (DL-PTSP) technique can compensate for the temperature sensitivity of PSP by composite measurement of temperature based on temperature-sensitive paint (TSP) technique. In addition, by applying lifetime-based method to DL-PTSP, the emission from a PSP layer and a TSP layer of DL-PTSP can be separated, because the order of the lifetime of the PSP luminophore, PtTFPP, is larger than that of the TSP luminophore, Ru-phen. This feature enables the simultaneous measurement of pressure and temperature by DL-PTSP with a single-camera equipment. In the previous study by Moon et al., data of emission decay of DL-PTSP for 50 periods of excitation must be accumulated to obtain a set of pressure and temperature data. This study enables to obtain a set of pressure and temperature data from emission decay of DL-PTSP for only one period of excitation, by setting appropriate timing of exposure gate of a high-speed camera. As shown in Figure 1 and 2, temperature and pressure sensitivity of the DL-PTSP is comparable to that of the previous work, while the SN ratio can be increased drastically because of the 50-times efficient data analysis. The result enables imaging measurement of pressure and temperature distribution on surfaces by using DL-PTSP.

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：慶應義塾大学日吉キャンパス（オンライン）   Country：Japan  

Applying the lifetime-based method to dual-layer PSP/TSP (DL-PTSP) enables the simultaneous measurement of pressure and temperature fields by using a single high-speed camera. Structures of intermediate layers between the PSP layer and the TSP layer of DL-PTSP may affect the sensitivity and the accuracy of measurement by DL-PTSP. In this study, the dependence of the thickness of a colorless poly(TMSP) layer, one of the intermediate layers beneath the PSP layer, on the sensitivity and the accuracy of measurement. It is clarified that the mass of poly(TMSP), which affects the thickness of the colorless poly(TMSP) layer, shows the dependence on the luminescence intensity ratio of the PSP layer and the TSP layer, which affects the independence of the temperature measurement by the TSP layer from the pressure sensitivity of the PSP layer.

Event date： 2020.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

温度不均一性がもたらす圧力計測誤差の補正を目的とした，PSPとTSPの複合手法であるDual-layer PSP/TSP (DL-PTSP) に対し，寿命法を適用した圧力・温度分布の同時計測を行ううえで，イメージング計測における計測感度および精度検証の観点から，カメラゲートの設定や色素濃度等，最適な適用条件を示すとともに，課題点およびその解決法について議論を行う．

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：鹿児島（オンライン開催）   Country：Japan  

Temperature dependence of pressure-sensitive paint (PSP) causing relatively large error in pressure measurement is still a serious problem. Dual-layer PSP/TSP (DL-PTSP) method overlaying PSP and temperature-sensitive paint (TSP) enables temperature compensation of PSP by composite measurement of pressure and temperature fields. Previous research by the authors applying the lifetime-based method to DL-PTSP enables simultaneous measurement of pressure and temperature, by separating the luminescence of PSP and TSP using the difference between their luminophore lifetimes, but it needed multiple-cycle measurement to obtain one set of data. In this study, we improve the method to enable to obtain one set of data from single-cycle light excitation and measurement, by modifying the timing of camera gates. The luminescence decay reflecting the lifetime of the PSP layer showed high pressure dependence and high SN ratio. However, the luminescence decay reflecting the lifetime of the TSP layer showed pressure dependence, since the effect of PSP decay cannot be eliminated completely. This problem can be solved by improving the composition of DL-PTSP to control the luminescence intensity ratio of PSP layer and TSP layer.

Event date： 2020.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン開催   Country：Japan  

Event date： 2019.12

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：JAXA 調布航空宇宙センター   Country：Japan  

ゲージ圧の小さい低速流れ場における圧力分布計測において，温度不均一性を補正することを目的として，PSPとTSPの複合手法であるDual-layer PSP/TSP (DL-PTSP) を適用した圧力・温度複合計測を行うにあたり，計測感度および精度検証の観点から，強度法および寿命法の比較検討，ならびに色素の組み合わせや撮影条件等について議論を行う．

Event date： 2019.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Hokkaido University, Sapporo   Country：Japan  

Dual-layer PSP/TSP (DL-PTSP) method can reduce the measurement error of PSP technique caused by temperature sensitivity of PSP. Applying intensity-based calibration method to DL-PTSP is relatively easy, because it does not require either high-speed imaging or pulsed light source. However, overlap of emission spectra of the two luminescent dyes results in insufficient separation of the two emission, reducing the sensitivity of both the PSP component and the TSP component. Lifetime-based calibration enables the separation of emission from the PSP and the TSP by using the large difference in their lifetime, even if their emission spectra overlap each other. On the other hand, insufficient difference in the lifetime may results in the decrease in the sensitivity of them. In this study the effect of the overlap of the emission spectra on the intensity-based calibration of DL-PTSP, and the effect of the difference in the lifetime on the lifetime-based calibration of DL-PTSP are discussed.

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：秋田大学　手形キャンパス（秋田県秋田市）   Country：Japan  

Event date： 2018.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：蓬崍殿（北海道室蘭市）   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：関西大学　千里山キャンパス（大阪府吹田市）   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：明治大学（東京都）   Country：Japan  

Event date： 2018.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学　伊都キャンパス（福岡市）   Country：Japan  

Configuration optimization of Dual-layer PSP/TSP for simultaneous measurement of pressure and temperature

Event date： 2017.12

Language：English   Presentation type：Oral presentation (general)  

Venue：Kumamoto University, Kumamoto   Country：Japan  

There are still very few applications of pressure sensitive paint (PSP) for measurement of nonstationary pressure distribution of internal flows in mechanical engineering fields. Application method of PSP taking the luminescent images of PSP through the transparent solid body (e.g. shroud wall of turbomachinery) and translucent PSP layer enables to apply PSP to the measurement of internal flows. However, this method results in low S/N, because PSP without opaque white basecoat has low luminescent intensity and overlaying image inside the body through the transparent material and PSP layer cause significant error in taking the luminescent image of PSP. To solve the problem, we have developed the application method of PSP by using an opaque, oxygen-permeable overcoat layer having porous structure made of nanoparticles of boron nitride (BN). This overcoat enables to increase the S/N of PSP in the transparent mode, which is needed for measurement of internal flows. In this study, we apply silica nanoparticle PSP having fast time response, because the pressure distribution on a shroud wall of turbomachinery is intrinsically unsteady. To analyze the effect of the opaque overcoat on the pressure sensitivity and the time response of the PSP, we have compared the properties of the PSP with the overcoat and those of the PSP without the overcoat. As a result, it is clarified that the opaque overcoat of BN nanoparticle does not reduce the pressure sensitivity and the time response of the fast-response PSP, which can detect periodical pressure change of the order of 100Pa and lower than 3 kHz. We have applied the fast-response PSP with the overcoat to the pressure measurement of an inner wall of a test axial compressor with the blade-passing frequency of 520Hz, and the qualitative images of the pressure distribution are obtained. We consider that the most significant source of the error in the pressure measurement is the temperature-dependence of the PSP. Therefore, the simultaneous measurement of temperature distribution is needed to increase the accuracy of the pressure measurement using the PSP.

Event date： 2017.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：室蘭工業大学（北海道室蘭市）   Country：Japan  

Development of Pressure Distribution Measurement Method on Inner Wall of Turbofan Using Pressure Sensitive Paint
Kazuya HANDA, Keishiro TAKEDA, Tomohiro IMAZEKI, Kil-ju MOON, Hideo MORI
Journal of the Visualization Society of Japan, Vol. 37, Suppl. 2, OS1-1-5

Event date： 2017.10

Language：English   Presentation type：Oral presentation (general)  

Venue：Okinawa Convention Center, Ginowan, Okinawa   Country：Japan  

The measurement method using PSP (Pressure Sensitive Paint) is useful to measure the two-dimensional pressure distributions on solid surfaces. However, PSP has not only pressure dependence but also temperature dependence. The error of temperature dependence becomes relatively large when measuring low-gauge pressure condition because PSP is absolute pressure sensor. To solve the problem, we designed DL-PTSP (Dual layer PSP/TSP) which stack up TSP (Temperature Sensitive Paint) and PSP layers, to apply TSP to temperature compensation of PSP. In the previous studies, we showed the temperature compensation effect of DL-PTSP with the intensity-based method at non-uniform temperature field in low-gauge pressure condition. However, the intensity-based method using DL-PTSP requires two cameras for simultaneous measurement of temperature and pressure because it requires two optical filters to separate the luminescence of PSP and TSP. In this study, we propose the method of simultaneous measurement using DL-PTSP with lifetime-based method. Big advantage of the method is to enable simultaneous measurement of pressure and temperature with a single camera, because the different lifetime of PSP and TSP enables to separate the luminescence of PSP and TSP without using two optical filters. In addition, DL-PTSP using lifetime-based method does not require wind off images, which may cause significant error of PSP with intensity-based method. At first, we show the dependence of the lifetime of mono-layer PSP and mono-layer TSP on the pressure and the temperature, to clarify the feasibility of the lifetime-based measurement method of PSP and TSP, and we propose the detailed method to separate the luminescence of them. Finally, we apply the lifetime-based method to DL-PTSP and suggest the possibility of temperature compensation of the DL-PTSP.

Event date： 2017.9

Language：English   Presentation type：Oral presentation (general)  

Venue：University of Hohenheim, Stuttgart   Country：Germany  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：埼玉大学（埼玉県さいたま市）   Country：Japan  

Measurement of Pressure Distribution around Internal Flows by Fast-response Pressure Sensitive Paint
Hideo MORI, Keishiro TAKEDA, Kazuya HANDA, Tomohiro IMAZEKI and Kil-Ju MOON

Event date： 2017.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：工学院大学（東京都）   Country：Japan  

Pressure/temperature simultaneous measurement method of dual layer PSP/TSP using lifetime based method
Kil-Ju Moon and Hideo Mori
Journal of the Visualization Society of Japan, Vol. 37, Suppl. 1, F113

Event date： 2016.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：山口大学　工学部   Country：Japan  

Measurement of pressure distribution in internal surface of turbo machinery by using pressure sensitive paint

Event date： 2016.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：山口大学　工学部   Country：Japan  

Research of pressure sensitive paint using lifetime based method for low pressure flow field

Event date： 2016.9

Language：English   Presentation type：Symposium, workshop panel (public)  

Venue：KAIST   Country：Korea, Republic of  

Nowadays fast-response pressure sensitive paints (PSP) have been developed [1], but there are still very few applications of PSP for measurement of nonstationary pressure distribution of internal flows. Applying PSP on a transparent solid surface (e.g. shroud surface of turbomachinery) made of glass or acrylic resin and taking the luminescent image of PSP through the transparent material results in low S/N, because PSP without opaque white basecoat has low luminescent intensity and overlaying image through the transparent material and translucent PSP layer cause significant error in taking the luminescent image of PSP. To solve the problem, we have developed the fast-response PSP with an opaque, oxygen-permeable overcoat layer having porous structure made of nanoparticles of boron nitride (BN), which enables to increase the S/N of PSP for measurement of internal flows. From the static calibration tests, it is clarified that the opaque overcoat of BN nanoparticle does not reduce the pressure sensitivity of the PSP. From the dynamic calibration tests using an acoustic resonant tube, we also have clarified that the opaque coating of BN nanoparticle does not reduce the time response of the fast-response PSP for pressure fluctuation whose amplitude is of the order of 100Pa, within the frequency range lower than 3kHz.

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学　伊都キャンパス   Country：Japan  

Measurement technique of pressure and temperature by dual-layer PSP/TSP with lifetime based method using high speed camera

Event date： 2016.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学　伊都キャンパス   Country：Japan  

Development of measurement technique for pressure distribution of inner flow of turbo machinery by using pressure sensitive paint

Event date： 2016.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Gatlinburg, Tennessee, U.S.A.   Country：United States  

Nowadays fast-response pressure sensitive paints (PSP) have been developed, but there are still very few applications of PSP for measurement of nonstationary pressure distribution of internal flows, because of the very limited optical access of the target system. By applying PSP on a transparent solid surface (e.g. wall of pipes or shrouds of turbomachinery, made of glass or acrylic resin) and taking the luminescent image of PSP through the transparent solid body, pressure distribution on the surface caused by internal flows can be measured in principle. However, low S/N caused by low luminescent intensity of PSP without screen layer and overlaying image through the transparent solid body and translucent PSP layer, acting as one of noise sources, is a serious problem for practical application of PSP. We have developed the fast-response PSP with an opaque overcoat layer having porous structure made of nanoparticles of boron nitride (BN) whose average particle size of 50nm, which enables to increase the S/N of PSP for measurement of internal flows. The pressure sensitivity of the PSP is examined, and it is clarified that the opaque overcoat of BN nanoparticle does not reduce the pressure sensitivity of the PSP. We also have examined the time response of the PSP by using an acoustic resonant tube, to compare the time response of the PSP with BN overcoat with that of the PSP without overcoat. As a result it is clarified that the opaque coating of BN nanoparticle does not reduce the time response of the fast-response PSP for pressure fluctuation whose amplitude is of the order of 100Pa, within the frequency range lower than 3kHz.

Event date： 2016.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Gatlinburg, Tennessee, U.S.A.   Country：United States  

The greatest advantage of the lifetime-based method for pressure sensitive paint (PSP) and temperature sensitive paint (TSP) compared with the widely used intensity-based method is that reference images are not required, because theoretically lifetime of PSP luminescence does not depend on luminophore concentration, paint thickness, photodegradation and paint contamination. However, lifetime of PSP luminescence as well as intensity has temperature dependence, and temperature compensation of PSP is needed to increase the accuracy of pressure measurement. To solve this problem, we introduced dual-layer PSP/TSP, the combining method of PSP and TSP. However, simultaneous measurement of pressure and temperature by the intensity-based method needs two cameras because different optical filters are needed to separate the luminescence of PSP and TSP. On the other hand, because luminophores of PSP and TSP has different lifetime, the two luminescence can be separated by using the lifetime difference instead of using different optical filters, allowing simultaneous measurement by dual-layer PSP with one camera. In this study we have clarified the lifetime sensitivity of the dual-layer PSP/TSP in low-gauge pressure conditions in order to show the feasibility of the dual-layer PSP/TSP with the lifetime-based method for the measurement in low-speed flow fields with temperature distribution. Normalized luminescence intensity at 22.5μs after the end of excitation light has high pressure dependence, while the luminescence of TSP has almost vanished at 22.5μs. On the other hand, normalized luminescence intensity at 6.25μs has high temperature sensitivity, while the pressure sensitivity at 6.25μs is very small. Using this combining method, temperature information obtained by the TSP can be used for the temperature compensation of the PSP.

Event date： 2016.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：熊本大学   Country：Japan  

Event date： 2015.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京理科大学   Country：Japan  

Event date： 2015.7

Language：English   Presentation type：Oral presentation (general)  

Venue：COEX, Seoul   Country：Korea, Republic of  

Event date： 2015.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：工学院大学   Country：Japan  

Event date： 2015.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学   Country：Japan  

Event date： 2014.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：富山大学   Country：Japan  

Measurement Technique for Unsteady Low-speed Flow Fields Using Polymer-type Pressure Sensitive Paint

Event date： 2014.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：熊本市国際交流会館   Country：Japan  

Event date： 2014.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：工学院大学   Country：Japan  

機械工学分野の研究開発において，感圧塗料（ＰＳＰ）を用いた固体表面の圧力計測技術を，流体機械内部流れなど複雑流れ場の実験的解析を通じて異常流動現象に関する有用な知見を得るためのツールとするには，低ゲージ圧領域におけるＰＳＰの圧力感度の低さやＰＳＰの温度依存性の存在，および曲面かつ大面積の対象物に対する励起光照射の不均一性など，圧力計測精度に大きく影響する数多くの課題点を克服する必要がある．本研究では，ゲージ圧が低く，かつ温度分布が不均一な場を対象とした圧力計測の精度向上を実現するため，励起光強度の補正法および感温塗料（ＴＳＰ）による温度分布計測を併用した温度補正法の適用によるＰＳＰの精度向上手法について議論する．これらの手法を，圧力上昇が小さく，かつ大面積の曲面であるプロペラファン動翼負圧面上の圧力・温度計測に適用し，ＰＳＰの精度向上効果を検証する．

Event date： 2014.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Okinawa   Country：Japan  

We apply pressure sensitive paint (PSP) to quantitative analysis of pressure distribution and visualization of shockwave structures on a sidewall in a supersonic flow passing through a turbine cascade. To compensate for the temperature dependence of PSP, we apply dual-layer PSP/TSP, the combination method of PSP and temperature sensitive paint (TSP) based on luminescent nanoparticles of ZnS-AgInS2 (ZAIS). Accuracy of the pressure measurement of the sidewall with non-uniform temperature distribution by the dual-layer PSP/TSP is examined in the supersonic wind tunnel tests, by comparing the pressure data obtained by the dual-layer PSP/TSP with those measured by pressure taps. The pressure distribution on the sidewall measured by the PSP component showed large error without temperature compensation, which is reduced effectively by the temperature compensation using the temperature distribution obtained by the TSP component. In addition, the shockwave structures visualized by the dual-layer PSP/TSP is compared with those obtained by the schlieren photograph. There is slight difference in shock angles and thickness between them, because the PSP visualizes the shockwave structure close to the sidewall while the schlieren photograph visualizes the shock structure in the mainstream.

Event date： 2013.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：JAXA調布   Country：Japan  

Event date： 2013.11 - 2014.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学伊都キャンパス   Country：Japan  

Measurement for pressure distribution on blade surfaces of consumer propeller fan using pressure and temperature sensitive paint

Event date： 2013.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：JAXA調布   Country：Japan  

Event date： 2013.7 - 2014.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：工学院大学   Country：Japan  

Visualization of the pressure distribution using dual-layer PSP/TSP in the supersonic flow field

Event date： 2012.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：同志社大学   Country：Japan  

Event date： 2012.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：JAXA調布   Country：Japan  

Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：高知大学   Country：Japan  

Accuracy of Pressure Measurement in Low Speed Flows by Dual-layer PSP/TSP

Event date： 2012.9

Language：English   Presentation type：Symposium, workshop panel (public)  

Venue：KAIST   Country：Korea, Republic of  

Pressure sensitive paint (PSP) is a powerful measurement tool to visualize pressure distribution on solid surfaces using emission of luminescent molecules, and application of PSP to analysis of complex pressure distribution in several experimental fluid dynamics (EFD) problems is strongly demanded. However, it is difficult to apply PSP to low-speed flow fields with small differential pressure and non-uniform temperature distribution, which may cause a significant error of the pressure measurement. Therefore temperature compensation of PSP is needed to obtain highly precise pressure distribution when PSP is applied to low speed flow field with low gauge pressure. In this study temperature sensitive paint (TSP) is employed for temperature compensation of PSP to increase the accuracy of pressure measurement using PSP in conditions with non-uniform temperature distribution. We have developed dual-layer PSP/TSP by painting PSP over a TSP layer. By using this method, temperature distribution on solid surfaces can be measured by TSP layer, and the temperature distribution map can be used for temperature compensation of PSP. We discuss the sensitivity of the dual-layer PSP/TSP in low gauge pressure conditions below 1kPa, and the effect of the temperature compensation to increase the accuracy of pressure obtained by PSP.

Event date： 2012.9

Language：English   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Venue：JAXA Chofu   Country：Japan  

Event date： 2012.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：工学院大学   Country：Japan  

Measurement Technique for Rotor Surfaces of Low-pressure Turbomachinery Using Pressure and Temperature Sensitive Paints

Event date： 2011.11

Presentation type：Oral presentation (general)  

Venue：Hotel Metropolitan Sendai （宮城県仙台市）   Country：Japan  

Event date： 2011.11

Presentation type：Symposium, workshop panel (public)  

Venue：宇宙航空研究開発機構　調布航空宇宙センター（東京都調布市）   Country：Japan  

Event date： 2011.9

Presentation type：Oral presentation (general)  

Venue：東京工業大学   Country：Japan  

Pressure measurement methods for blade surfaces of propeller fan using pressure sensitive paint

Event date： 2011.7

Presentation type：Oral presentation (general)  

Venue：アクトシティ浜松　コングレスセンター（静岡県浜松市）   Country：Japan  

Event date： 2011.7

Presentation type：Oral presentation (general)  

Venue：工学院大学   Country：Japan  

Temperature compensation of PSP component for dual-layer PSP/TSP in low-speed flow

Event date： 2011.3

Presentation type：Oral presentation (general)  

Venue：九州大学伊都キャンパス   Country：Japan  

Event date： 2010.10

Presentation type：Oral presentation (general)  

Venue：山形大学工学部   Country：Japan  

Event date： 2010.10

Presentation type：Oral presentation (general)  

Venue：霧島市国分シビックセンター   Country：Japan  

Event date： 2010.9

Presentation type：Symposium, workshop panel (public)  

Venue：名古屋工業大学   Country：Japan  

Event date： 2010.7

Presentation type：Oral presentation (general)  

Venue：工学院大学   Country：Japan  

Event date： 2010.6

Presentation type：Oral presentation (general)  

Venue：Daegu Exhibition and Convention Center (EXCO Daegu)   Country：Korea, Republic of  

Event date： 2010.5

Presentation type：Oral presentation (general)  

Venue：Beijing Friendship Hotel   Country：China  

Event date： 2010.5

Presentation type：Oral presentation (general)  

Venue：Kyushu University   Country：Japan  

Event date： 2009.11

Presentation type：Symposium, workshop panel (public)  

Venue：JAXA　調布   Country：Japan  

Event date： 2009.11

Presentation type：Oral presentation (general)  

Venue：名古屋工業大学   Country：Japan  

Development of Measurement Technique at Low-speed Flow Fields using Pressure Sensitive Paint

Event date： 2009.8 - 2009.9

Presentation type：Symposium, workshop panel (public)  

Venue：Regensburg   Country：Germany  

Event date： 2008.9

Presentation type：Oral presentation (general)  

Venue：Sendai   Country：Japan  

Event date： 2007.12

Presentation type：Oral presentation (general)  

Venue：岐阜   Country：Japan  

Experimental Analysis for Sidewall Shape Optimization for Linear Aerospike Nozzle using NO-LIF and PSP

Event date： 2007.11

Presentation type：Oral presentation (general)  

Venue：広島   Country：Japan  

Analysis of rotational energy of nitrogen molecular beam by REMPI

Event date： 2007.9

Presentation type：Oral presentation (general)  

Venue：岐阜   Country：Japan  

Sidewall Shape Optimization for Linear Aerospike Nozzle using NO-LIF and PSP

Event date： 2007.8

Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Measurement of rotational energy of nitrogen molecular beam by REMPI

Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

Application of Pressure Measurement Technique by Pressure Sensitive Paint to Mechanical Engineering

Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

Measurement of Temperature and Density for Highly Rarefied Gas Flows
（Resonantly Enhanced Multiphoton Ionization）

Language：Japanese  

Development of Pressure Sensitive Molecular Film by Langmuir-Blodgett method

Language：English   Publishing type：Internal/External technical report, pre-print, etc.  

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Academic society, research group, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Number of participants：532

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Number of participants：700

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Academic society, research group, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Academic society, research group, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc.