The technique to measure spark plug temperature in an engine combustion chamber was developed. As for this technique, the infrared image of a spark plug in a visualization engine is captured with an IR camera. The visualization window which stands up to the environment of the combustion chamber which reaches 100 atm and 2000°C is attached, and this technology can measure a plug temperature to drive in the high load. Furthermore, this technology can measure a change in plug temperature in every cycle.

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In the present study, unsteady-state friction heating experiments and corresponding numerical analysis have been conducted for the purpose of evaluating the effective dynamic coefficient of friction μ between a rotating rod and a copper plate, which is regarded as one of essential key parameters for elucidating heat transfer process in friction welding, friction stir welding, spot friction welding, surface modification, and so on. It has been shown that, the effective dynamic coefficient of friction μ of copper plate is evaluated from about 0.30 to 0.35 to first approximation, and almost no effects of the tip radius of rotating rod on μ has been observed under the present experimental conditions.

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Recently electronic equipments get gradually small. Therefore the fluid temperature measurements using contact-type thermometers are more difficult. The liquid crystals change the color depending on temperature. The liquid crystals mixes into the fluids (water, oil, etc, , , ) which enable to do non-contact measurements. We use a Neural Network to measure the temperature from the color. It is an advantage that the method can effectively uses the temperature measurement range of liquid crystal. But the method is of doubtful accuracy. We use the design of experiments and the robust design to improve an accuracy of measurement. As a result, ± 0.05 degree Celsius measurement is possible.

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We have studied inherent fluorescence spectra of fingerprints and various papers in the deep UV region with a nanosecond pulsed laser system and have visualized latent fingerprints on papers with the time-resolved fluorescence imaging method. The excitation wavelength is 230 nm and 280 nm. Fingerprints emit fluorescence from 300 nm to 500 nm. Since papers also emit fluorescence above 400 nm and it is quite strong, it is necessary to suppress paper fluorescence using filters for imaging latent fingerprints. For printed papers, inks or toners often emit fluorescence. By using appropriate filters, latent fingerprints on papers were visualized for all white and printed papers examined. We have also studied absorption images of fingerprints and obtained clearest images with 215-nm illumination for latent fingerprints on white papers.

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Several bi-leaflet prostheses (the St. Jude Medical(SJM) valve etc.) were tested in the mitral position under pulsatile-flow condition. Dynamic PIV system was employed to analyze the flow field affected by the leaflet shapes and valve designs. Scanning PIV was developed to measure the three-dimensional flow inside the ventricular. The pulsed Nd:YLF laser was scanned by a polygon mirror in other to provide several light sheets inside ventricular. Detailed chronological comparison of the flow fields associated with the opening, accelerating, peak and closing phase of the flow revealed the significance of the leaflet and overall valve designs on the flow field. The Scanning PIV system was applied successfully to the study of the three-dimensional flow field.

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Accurate information on sea grass distribution is an essential prerequisite for managing sea grass resources in coastal area. In this study, a method to estimate sea grass mapping using high-resolution images such as satellite data or aerial photograph for is developed based on an inversion of reflectance estimation at seabed. The mapping method simulates parallel, radiative light transfer in the water and at sea grass approximated by using principles of geometric-optics transportation. To examine validity proposed of model, field surveys along sea grass meadows were conducted to obtain actual sea grass coverage. The estimated sea grass coverage from the image shows nice agreement with the observed data.

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We are aiming at the development of an inexpensive system that can shoot, record, and analyze the minute world of nano-scale. As the first step, a new visualization system was built using a household high-definition video camera (HDR-HC3) and an optical microscope with the darkfield illumination. And, we evaluate its usage in ferromagnetic nano-particles visualization of magnetic fluid, and make sure its effectiveness in it.

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We have conducted a basic experiment on visualization of a pipe which is used for transport catalyst in industrial use. First two copper-electrodes are attached to inner side and outer side of the container. We have charged 5volt to the interelectrode and have changed frequency from 5kHz to 100kHz to obtain stable capacitance. The experiment has two conditions that container is filled with catalyst or air. The stable conditions have been confirmed at the time more than 50kHz. We have made a CT sensor with 12 electrodes attached to the pipe which has diameter of 270mm based on the experiment result.

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Almost nothing is visible in water because of the large attenuation of light. This paper presents the brief history of underwater acoustics and the latest acoustic technology for underwater visualization. Aristotle(384-322 B.C.) has recognized that sound could be heard in water as well as air. Leonardo da Vinci(1452-1519) observed that one could hear ships from afar. Paul Langevin(1872-1946) detected a submarine for the first time, in 1918, as deep as 1500 meters with his piezoelectric transducer.
Underwater detection systems were developed for the purpose of underwater navigation by submarines in World War I and in particular after the Titanic sank in 1912. Many types of SONAR(SOund NAvigation and Ranging) were developed, Echo sounder, Side scan sonar, Multi-beam echo sounder(MBES), Scanning sonar.
Today new acoustic equipments produce the 3D image of seabed, and the underwater movie.

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The aerial laser survey is the advanced technology of measurement of altitude by means of laser irradiation device installed in the aircraft. The accuracy of altitude measured by laser is ±10cm in horizontal, and ±15cm in vertical respectively. In this paper, by using aerial laser survey data, space occupation ratio was shown as an example of visualization of appearance of city. Space occupation ratio was found to be corresponding to the land use, such as residential area was high space occupation ratio and river and main roads were low. It was shown through the example that the appearance of the city can be made visible by the expression of statistical characteristics reduced by making full use of the original laser data.

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This paper describes a detection method of two types of exfoliations for outward tile wall. One of the tile exfoliations is an outer exfoliation separated the tile surface from mortar concrete, the other is an inner exfoliation deteriorated space between the substrate and mortar concrete. In order to research these exfoliations, we focused attention on the wavelet analysis that enable to analyze the frequency element of a waveform on time phase continuously. An impulse sound by a small hammer was measured using a mockup wall that reproduced two types of exfoliations, and then these sound data were inspected by wavelet analysis. As a result, the characteristics of two exfoliations were semi-empirically recognized visualizing the wavelet plane and the quantitative parameters judged the two exfoliations were obtained processing the wavelet data statistically.

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Liquid spray is mainly made up of tiny spherical droplets fully atomized and small non-spherical ones which may be deformed or sheared by liquid injection.
This paper presents the technique of phase-shifting digital holography for measuring ellipsoidal objects distributed in 3D space, objects which are the typical non-spherical ones. Hough transform is employed for detecting the minor and major axes for each ellipsoidal object on reconstructed images. Numerical simulated results show that the number of objects is successfully counted and thee minor and major axes are measured with accuracy using the present method.

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A lot of slurry fluids have an opaque substance. It is difficult to visualize using previous photograph system with a visible ray. Therefore, we use the X-ray photograph to visualize inside a slurry fluid. And also to capture three-dimensional flow structure of the slurry flow, we use two X-ray sources and detectors. Time-serial data of the particle position are obtained by particle tracking and stereo-pair matching techniques. 3-Dimensional velocity vectors inside the slurry fluid are obtained

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When a portion of a straight open-channel is replaced by a channel with a side cavity zone, water surface in the main channel in front of the cavity as well as that within the side cavity zone begins to show significant surface oscillation for specific experimental conditions. The mode of the oscillation changes with hydraulic condition and aspect ratio of the side cavity shape. When the aspect ratio is small, only a seiche-like oscillation within the cavity zone can be observed. However, as the streamwise length of the cavity increases, i.e. for a large aspect ratio, the oscillation in the cavity zone propagates into the main channel and a longitudinal oscillation becomes evident. In order to understand the mechanism of such mode-change, we performed a stereoscopic measurement of the water surface flow oscillation by gradually changing the aspect ratio of the side cavity.

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In recent works, the authors have reported an extension of PIV, called "Interface Gradiometry" (PIV/IG) that, by shearing templates to various degrees, directly measures the instantaneous velocity gradient at a fixed wall. This approach works well when the height of templates is carefully chosen. Our recent generalization of the original PIV/IG (denoted PIV/IG+; Nguyen & Wells 2006), does not require a template height to be specified a priori for pattern matching, and is thus more widely applicable. It also introduces an image transformation to handle curved boundaries. The present communication considers the sensitivity of PIV/IG+ results to errors in estimated wall position.

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The purpose of this research is to explore the mechanism required for the generation of earthquake vibration on the propagation velocity of the crack in fault plane. In this research, the impact splitting tensile tests of mortar and granite were carried out, and the propagation velocity of the crack was visualized and obtained by image analysis using ultra high-speed video camera. A relationship between the impulse which is impact loading and propagation velocity of the crack was observed. There appears to be a critical state in which propagation velocity does not increase, even if impulse is increased over it. It was proven to converge in 2.6 km/sec. Next, the mechanism of the development of the dynamics of the crack by the impulse was examined from displacement vector and Particle Image Velocimetry (PIV) analysis.

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To measure the diameter and the terminal velocity of the naturally falling raindrops, consecutive images of the falling raindrops were taken by using the ultra-high-speed video camera developed by the authors. The terminal velocity and the diameter of the raindrops were calculated from these images.
As a result, the behavior of the raindrops that moved downward along with the time passage was clearly observed from the consecutive images, and the relationship between the terminal velocity and diameter was obtained.

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When a viscous drop impacts onto a thin film of ethanol on a solid surface, a lot of hole formations can be observed on the eject crown. The holes are caused by the Marangoni instabilities, which occur at a point where ethanol droplets contact at crown wall of viscous drop. The high-speed video camera, of which frame rate is a million frames per second, is employed for detailed observations.

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We demonstrate spatially and temporally continuous motion pictures of three-dimensional image of femtosecond light pulses propagating in non-uniform optical media. Light-in-flight recording by holography is applied to record the motion pictures. To record the three-dimensional image of the light propagation, a weakly diffusive optical medium with adequate volume made by gelatin jelly is introduced to the recording optical setup of the holography. A 226-femtosecond light pulse is incident into a graded-index medium consisting of gelatin jelly and sugar in the recording process. Then the recorded hologram is illuminated by a continuous wave laser operated at 728nm wavelength, which is the same as that of the laser pulse used in the recording, then we can clearly observe propagation of light pulse gradually curving. Also a 226-femtosecond light pulse is incident into a diffraction grating located in a uniform and diffusive medium in the recording process. Then we can observe diffraction of light pulse which split into three pulses and drastically changing the propagation direction.

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We present a technique to record and observe motion picture of three-dimensional image of femtosecond light pulse propagation. The technique was attained by light-in-flight recording by holography. The holography uses an ultrashort pulsed laser as an optical source for the recording. To record the three-dimensional image of light pulse propagation, weakly diffusive medium with adequate volume was introduced to the recording optical setup of conventional light-in-flight recording by holography. Temporally and spatially continuous motion pictures of three-dimensional images of a 373-femtosecond light pulse propagating in gelatin jelly were observed. We found from the motion pictures that the shape of the reconstructed image was horizontally flipped. To analyze the flip, we modeled image-recording and reconstructing process in the technique and numerically simulated the shape of the image based on the model. The shape of the reconstructed image in the simulation agreed with that of experimental result, thus the validity of the modeling and analysis was verified.

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The authors have developed image sensors for vide cameras with the maximum frame rate more than 1, 000, 000 fps (frames per second). They also have designed an image sensor, the PC-ISIS, Photon-Counting In-situ Storage Image Sensor, with the ultra-high frame rate and the ultra-high sensitivity close to the photon-counting sensitivity as well, which is under preliminary evaluation. The sensor is based on the innovative structures for the ultra-high performance, such as the ISIS structure for the ultra-high frame rate, and the CCM, Charge Carrier Multiplier, together with the backside illumination and cooling for the ultra-high sensitivity. Once the performance of the PC-ISIS is confirmed, some derivatives of the sensor that have also ultra-high performance can be designed for various scientific and engineering applications by using the structures and the process applied to the PC-ISIS. A cooperative research project is proposed to search for the possible applications and to prepare the specific designs for the various applications.

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A new photographic method that enables to catch a whole shape of a fuel spray with quite fine droplet sizes is developed. A self-made camera that is composed of a large sized film and a self-made projector was used for this purpose. The self-made projector has an objective lens with high magnification and a long working distance. Using the large sized film, it is possible to photograph objects with both a desirable wide visual field and a fairly good spatial resolution at the same time. In the experiment, laser transmitted light has been developed to consider adequacy of this photographic system for a non-evaporative spray. The light source was the second harmonic of Nd:YAG laser. As a result, the fine image of the spray was taken by this system. There is the possibility of measuring the droplets diameter in the whole spray by using photographic system.

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Three-component velocity measurement has been performed for micro flow using a 3-D micro-PIV technique. Sequential volumetric particle images are obtained using a high-speed 3-D confocal scanning microscopy. The present 3-D confocal system consists of a microscope, a Nipkow disk-based multi-spot confocal scanner, a piezo-driven objective positioner, and a high-speed camera. This system can scan the cubic domain of 240×180×19μm in less than 100 milliseconds as changing the position of the confocal plane quickly in the out-of-plane direction by the objective positioner. As the result, we can record time series of 3-D spatial distributions of tracer particles in slow micro flow. All three components of velocity are obtained applying a 3-D PIV algorithm based on the 3-D cross-correlation method to the sequential volumetric images. We have measured a 3-D flow in a microchannel with a step using the 3-D micro-PIV technique. The out-of-plane component of velocity has been measured successfully in addition to the in-plane velocity distribution.

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The interaction between the oscillating jet and the wedge produces a fluctuating flow field outside the jet which in turn affects the motion of the jet. However, microscopic evidence of these phenomena remains undisclosed. In the present study, an optical system-operated PIV technique was employed to obtain the time-wise variations of both the velocity-vector and vorticity distributions. With the aid of LDV measurements, the Reynolds stress and power spectral distributions were also acquired. In conclusion, the micro PIV measurements have for the first time disclosed the location and flow process characteristics of the edge-tone source. In addition, the micro flow behavior of reciprocating migration of the conjunct separation vortex pair over the rear edge of the third-row cylinder is confirmed as the mechanism of flip-flow oscillations induced by the edge tone phenomenon.

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The purpose of this research is to clarify swimming mechanism of Water flea which could be a model of micro-machine. Its motion and flow around it have been experimentally visualized by microscopic particle image velocimetry (PIV). Water flea swims pushing water behind generating two type vortices. One is around its body and another is at the tip of second antenna. Study on the effects of these vortices are underway and it seems vortex around its body plays a role for propulsion.

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An oscillatory flow was employed to improve the highly effective mixing process in a Y-shape micro-channel. In the oscillatory flow, it is clarified on numerically and experimentally that a decrease in frequency and/or an increase in amplitude contribute to increase in the interfacial area between two liquids.

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In order to make the X-ray micro-PIV technique as a common technology, the alternative X-ray source to Synchrotron Radiation (SR) facility is indispensable. The characteristics of micro-focus X-ray (MFX) source are examined for the micro-PIV. The MFX source seems better than the SR, in respect of the availability, the flexibility for PIV systems, and image enlargement. X-ray PIV is the only method that provides us with a method to realize three-dimensional micro-PIV measuring flows in complex channels. The spatial resolution, intensities, and imaging methods are discussed. Three dimensional shape of a spiral shape of fine metal wire is reconstructed from a two-dimensional micro-focus X-ray picture.

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In order to measure instantaneous three-dimensional velocity distributions in a small space, three-dimensional micro-PIV technique have to be developed. In this paper, the improved eccentric aperture method that could be conveniently applied to the three-dimensional PIV measurement in a small space is discussed. By introducing a color separation technique, the measurement distance can be expanded twice, and it can process dense tracer pictures. Some experimental examples are shown.

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Rapid mixing is essential on the micromixer in microfluidic systems. Mixing in microchannel relies mainly on molecular diffusion due to the laminar flow at low Reynolds number. In this study, the sequential switching of electroosmosis flow is applied to the mixing in microchannel. By switching of the electroosmosis flow sequentially to the T-junction microchannel, the mixing stream is segregated by the two inlet streams on and off, then the mixing process can be accelerated and controlled by increasing the contact surface of two liquids. The flow pattern was classified into two patterns, wavy flow pattern and segmented flow pattern, by Strouhal number. The mixing degrees can be expressed as a function of Strouhal number.

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Although the phenomena related to the multiphase flow can be found in many kinds of industrial and engineering applications, the physical mechanism of the multiphase flow has not been investigated in detail. The major reason for the lack of data in the multiphase flow lies in the difficulties in measuring the flow quantities of the multiple phases simultaneously. The difference in the refractive indices makes the visualization almost impossible. The authors of this study have developed the technique for the simultaneous visualization of the both phases of the liquid-liquid two-phase flow by adjusting the refractive indices of both phases. In this study, the PIV measurement has been carried out for a water droplet falling near the wall in the stationary oil. The results reveal the typical features of the effect of the wall on the convection around and inside of a droplet.

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A simple design micro-heat pipe was proposed. It was composed of 20.0×20.0 mm square flow circuit which had two adjacent narrow-sides and two adjacent wide-sides. A heating spot was at the narrow side and a cooling spot was at the wide side. Working fluid was ethanol. The flow circuit was placed horizontally. Bubbles generated at the heating spot migrated toward the wide side, the bubbles coalesced there to form a large bubble, and then the large bubble moved to the cooling spot. Finally, the large bubble was condensed at the cooling spot. This cycle repeated continuously. As a result of it, heat transport from the heating spot to the cooling spot was produced in the micro heat pipe. Temperature property and flow state in channel was confirmed. An analysis of a flow mechanism was performed by solving a simple flow equation based on the flow resistance. It was proved that one-way circulation flow could be formed in the flow circuit. Predicted flow velocities were close to measured velocities.

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Liquid jets from a nozzle were visualized and recorded using a high-speed video. Water and PVA solutions with various viscosities were used as test fluids. Liquid with relatively low viscosity makes a liquid column near the nozzle. The column breaks into satellite droplets. When the viscosity of liquid increased, larger droplets are directly created without the liquid column and satellite droplets are not observed.

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The flowfield analysis around a model of space plane traveling at Mach 10 has been carried out utilizing an Electrical Discharge Method and a Finite Element Method scheme. In this study, the experiments and the numerical simulations were carried out under the conditions the angle of attack were 0 and 10 deg. Furthermore, the experimental results were compared with the numerical ones. In these comparisons, it was found that they were relatively in good agreement.

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A polymer electrolyte fuel cell (PEFC) is expected to be a next generation power source for automobiles and home station generators because of its efficient and clean operation. Solid polymer membrane used as electrolyte of the PEFC shows high performance in a moderate hydration condition. However, the performance is remarkably deteriorated in excessively high or low hydration conditions. Therefore, appropriate water management is important in order to keep the PEFC in efficient, and stable operation. This research was aimed to clarify the relationship between the waterdrop behavior and the characteristics of the fuel cell. To grasp moisture condition in the cell, a visualization fuel cell was developed whose cathode gas channels condition can be observed by direct watching. With the experimental equipment, continuous operation test were conducted varying the cell temperature and the gas utilization, and the cell characteristic and the waterdrop behavior inside the cathode gas channels were observed.

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Volatilizing of molten carbonate as electrolyte in Molten Carbonate Fuel Cell (MCFC) is one of degradation factors. The Volatilization of the molten carbonate brings the cross-leak and the corrosion of the metallic materials. Moreover, the piping blockage caused by solidification of the volatile chemical species in piping will be happened at lowering temperature. Especially, since the reforming catalysts filled to the anode channel in Direct Internal Reforming Molten Carbonate Fuel Cells (DIR-MCFC) are polluted by volatile species from the molten carbonate, volatilizing of the molten carbonate is an important issue. However, the behavior of molten carbonate volatile issue has been not elucidated, since the volatilization volume is too small amount to analyze them. Last symposium, we informed that at anode side, amount of volatilized particle was increasing with increasing current density. Although volatilization phenomenon was observed at cathode side, there was no relationship between amount of volatilized particle and current density. The volatile chemical species from anode and cathode were potassium rich composition.

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Recently, the sludge increase dramatically with the economics development, this disposal is big issue. Moreover, the electric consumption also increases with the economics development. Although a new energy development such as fuel cell is promoted about the problem of the power consumption, the correspondence of the disposal of the sludge is promoted hardly. Therefore, we propose the gasification system for which the sludge gasify by molten salt. Moreover, this gasification gas is used as fuel gas of MCFC. This paper elucidates the fundamental characteristics of the gasification of the sludge. The crucible filled with the molten salt is installed in the reaction vessel, and can be set to an arbitrary temperature and the gas atmosphere. The sludge is supplied into the molten salt, and is gasified. The chemical composition of the gasification gas is analyzed by HC meter, SOx meter and the gas chromatography. As a result, although the gasification of sludge by molten carbonate can generate CO and H2 as same as the chemical equilibrium value, the molten carbonate was not able to absorb SOx enough. HC causes carbon deposition at the exhaust pipe because the moisture of the sludge is a few. Consequently, the sludge can be expected as the fuel for the gasification which uses the molten salt.

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Recently CFD simulations have been widely utilized for investigating indoor air environments. However, these quantitative observations are currently unsatisfactory, especially for natural 'convections in enclosures. By utilizing a scale model of a residential room equipped with a floor panel heating system, this study aims to provide detailed experimental data in order to verify observations made using CFD on natural convection. Here we present results of the PIV measurement in the boundary layer along the heated bottom surface of the test chamber. The test space was a rectangular enclosure filled with water. The bottom surface was uniformly heated and one of the vertical walls was cooled. The Rayleigh Number was kept at a constant value of 3.1×10¹⁰. To make the flow near the wall more visible, fluorescent tracers were used. A thin punching plate was set along the measuring plane in order to measure the image distortions caused by the non-uniform temperature field. The distorted image data were used to correct velocity data, and thus more accurate velocity distribution was obtained.

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In order to understand the formation and the development of the plume structure in turbulent thermal convection, the temporal and spatial variations of temperature and velocity field are measured in the non-penetrative thermal convection of the horizontal fluid layer using the combined liquid crystal thermometry and stereo-velocimetry. It is found that the spoke structure is generated near the heated surface and moves along the heated surface unsteadily changing the cell size. The thermal plume is generated from the high temperature region of the spoke structure, where the vertical velocity component is clearly observed near the heated surfaces.

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Marangoni (or thermocapillary) convection in a liquid bridge reaches an oscillatory state when the temperature gradient along the free liquid surface exceeds a critical value. The oscillation appears in surface temperature, surface velocity and surface deformation. The clarification of the phase relationship in their oscillation is vital for better understanding of oscillation mechanisms. The present paper reports experimental results obtained through a sophisticated combination of multiple techniques for those oscillating quantities.

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Experimental investigations have been carried out on natural convective flows over a heated L-corner in which the vertical plate was shorter than the horizontal plate. Special interest was paid to the fluid flow and heat transfer around the vertical plate. The height of vertical plates, H, were varied as H=10-150mm. The width of horizontal plate was 350mm constant. The test fluid was water. The flow fields and the surface temperatures were visualized with fluorescent dye and liquid crystal thermometry, respectively. The local heat transfer coefficients of the vertical plate were also measured. The result shows that the recirculating flow appears irregularly around the vertical plate when H is less than 30mm. It is also found that the local heat transfer coefficients show a maximum at H/2 when the recirculating flow appears around the vertical plate.

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The propulsion method of the aquatic life is a result of optimization by evolution. Research of the propulsion method is useful for the design of robot that operates efficiently, for example swimming-robot etc. This study is about a loath that swims bending whole body. Our purpose of research is to clarify its swimming mechanism through flow field analysis. We analyzed the three-dimensional flow field around the loath using stereoscopic PIV, about both horizontal cross section and vertical section. As a result, we captured three-dimensional flow field and vortex structure around the loath.

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It is very important to reveal coherent horizontal vortices, in meandering compound open-channel flows for predicting the transport and distribution of suspended sediment in actual rivers. However, in previous studies, flow-visualization techniques such as PIV and PTV, have not sufficiently been applied to such flows, and thus, there is almost no detailed information on coherent turbulence in meandering compound open-channel flows. Therefore, we conducted innovative flow-visualization measurements by using a multi-layer scanning PIV system, and analyzed instantaneous velocity vectors on horizontal planes at several different elevations simultaneously. As the results, the time-space correlations between the different elevations, the vortexcore motion and instantaneous velocity properties were revealed in the meandering compound open-channel flows.

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In this paper, fluctuating surface pressure measurements are made for four flat roofed building models with square or rectangular plans in order to examine wind load combinations. The fluctuating pressures are integrated over all their surfaces and results are obtained as along-wind force, crosswind force, vertical force and torsional moment on their frames. The maximum wind force in consideration of the wind direction component and other simultaneously observed wind force components are examined, and some interesting facts regarding the wind force combinations are discussed on" the basis of absolute value correlations, phase-plane expressions and so on. This investigation concurrently measured wind pressure applied to a wall surface and the resulting wind flow field around the building using a wind pressure model and DPIV systems. Data obtained through the measurements enabled identification of the wind flow field around the building that results from the maximum and minimum wind force applied to it.

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Buoyancy-driven exchange flows of helium-air were investigated through inclined a small opening. Exchange flows may occur following a window opening as ventilation, fire in the room as well as a pipe rupture accident in a high temperature gas-cooled nuclear reactor. The experiment has carried out by a test chamber filled with helium and flow was visualized by the smoke wire method. By removing the cover plate placed on the top of the opening, the exchange flow initiated. Air enters the test chamber and the mass of the gas mixture in the test chamber increased. The flow behavior has recorded by a high-speed camera with a computer system. The image of the flow was transferred to the digital data, thus the flow velocity was measured by PTV software. The volumetric exchange flow rate was evaluated from the PTV method and mass increment method. In the case of inclination openings, the results of both methods were compared. The detected data was arranged by the densimetric Floude number of the exchange flow rate that derived from the dimensional analysis.

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To characterize sliding behavior of water droplets with dynamic contact angles on hydrophobic, the instrument was developed. Sliding action of the droplet was classified into three motion categories: constant accelerated motion, constant velocity and stasis. The action of the sliding droplet was controlled by the interaction between solid and liquid surface. This interaction was expressed by the internal fluidity of the sliding droplet. The device with PIV facilitated the measurement of the sliding acceleration, shape variation and internal fluidity in the sliding droplet.

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Many studies on unsteady flow around an unsteady airfoil at low Reynolds number region have been carried out with experimental and numerical approaches. However, the detailed vortex flow structure and the characteristics of dynamic forces have not been understood sufficiently. In order to clarify the detailed vortex flow structure behind unsteady airfoils at low Reynolds number region, we have carried out the particle image velocimetry (PIV) measurement behind an unsteady airfoil in pitching and heaving motions and numerical simulation by advanced vortex method. Moreover, we have performed the numerical simulation behind an elastic airfoil.

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This paper proposes a novel algorithm using an artificial neural network for modelling both 3-D flow velocity vector and concentration fields from measured values and boundary conditions. By using its trained neural network, we can estimate 3-D velocity vectors and concentrations over the entire field. The network is trained by using sparsely measured values and boundary conditions as teaching data so that the output of the network agrees well with those data. In addition, the continuity and the diffusion equations are systematically satisfied by the model inclusive learning. In order to evaluate the effectiveness, the proposed method is applied to air flow fields in the full size model of an infection-free hospital room. The concentration distributions in the room are estimated and then compared with the experimental smoke concentration data over the field for validating the proposed algorithm. The estimated results grasp the experimental diffusion behavior.

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The authors have considered the higher-order analysis on multi-frame correlation information in spatio-temporal field. The latest innovative optical devices enable us to obtain more than sufficient information to obtain mean values. Present approach allows us to get acceleration and spatio-derivatives by considering the accumulation of multi-frame correlation maps. The VSJ standard images were used for the evaluation of their performances. The authors also have proposed an inductive approach, which will offer us further development of for the higher-order analysis.

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Artificial respiration techniques for patients with respiratory disorder are important as a basic life support treatments for the patients. The nasal CPAP (Continuous Positive Airway Pressure) is a typical clinical treatment for infants keeping self respiration. Some devices for the nasal CPAP have been used in clinical procedure. However, in order to reduce the load for patients in the treatments, the downsizing and improvement of fitting of the devices are required. A new type device of nasal CPAP has been developed by the authors, but its performance in MAP (Mean Airway Pressure) variation did not meet the condition for clinical use. In this report, the performance of a nasal CPAP device improved has been investigated and it has been clarified that the performance was meet to clinical use.

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Stem cell culture becomes a key technology for the medical treatment of patient and implant technology. In this process, the cell size and the rate of necrosis is influenced on the fluid dynamical condition, such as maximum flow velocity, shearing slress, Reynolds stress, etc. According to the previous repornt, the cell size was detenrmred by the turbulence ofthe flow, in which the Kolmogorov's scale becomes important parameter in cell culture. In the present study, velocity measurement was camied out in whole flow field and local area. From the experimental results, it was shown that the fluctuation of velocity and vorticity had Kolmogorov's scale. The estimated shear stress obtained from the velocity distribution showed a good agreement with the previous nivestigation.

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