Circular dynamic stereoscopy (CDS) has special advantages as it enables 3-D measurements using a single CCD camera without any cumbersome settings. Annular streaks are recorded using this system and the size of the annular streaks directly relates to the depth/distance from the CCD camera. That is, the size of annular streaks is inversely proportional to the depth/distance from the CCD camera and therefore three-dimensional information can be measured automatically by image processing techniques. In this paper, PIV system using circular dynamic stereoscopy is introduced. Experimental results demonstrate the feasibility of our method.

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Three-dimensional measurement has achieved a high level of satisfaction in limited fields. Nevertheless, if the measuring object includes complex parts, unmeasurable area exists for occlusions of the part on its surface in many cases. In order to reduce the unmeasurable area, we developed a measuring system using a CCD camera and 3D magnetic sensors. The system enables a separated free scanning of a CCD camera and a laser-slit using the 3D magnetic sensors. Many numbers of views of each model from different orientations can be taken on measuring the configuration between a CCD camera and a laser-slit simultaneously. The information of different views is combined to reconstruct the 3D object on a computer display. Experimental results show the feasibility of our system.

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Velocity of swirling flow has been measured by 3D-PIV to analyze the frequency patterns of the azimuthal velocity with modal wavelet image processing. The swirling flows are two types, one inlet and four inlets around a vertical pipe. As a result, the wavelet levels at middle and high frequency of four inlets type are lower than that of the one inlet type. It means four inlet types has a possibility that a rod-like material would be conveyed with an orientation in swirling flow experientially.

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Flow pattern of the wake past two cylinders that are arranged in side-by-side is investigated experimentally by flow visualization and particle image velocimetry (PIV). We exploit the method of stability analysis to classify flow patterns, where we decompose flow field into mean and disturbed field. We found that flow pattern past two cylinders is classified into five typical ones from the analysis of the velocity fields obtained by PIV. The experimental results are compared with those from numerical analysis.

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The authors identified the existence of an "energy source point" with the maximum kinetic energy resulting from the collision of two intersecting streams. Its quantitative explanation of interaction between the intersecting main streams and wake flow in the divergent-flow region of the flow passage is definitely needed in order to disclose the flip-flop flow mechanism. Flow measurements using piezo meter, LDV and PIV were performed to investigate the pressure and velocity distributions inside a diamond-shaped cylinder bundle. It is disclosed that the existence of "energy source point" in the divergent-flow region plays an important role for generation of flip-flop flow.

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This paper presents an experimental study of turbulent flow through a squared-sectioned duct with a 180-deg sharp turn. Fluid flow fields are investigated using a laser-Doppler velocimetry, PIV and a visualization method. The mean velocity features of the primary and secondary flows, and the fluctuating longitudinal-velocity at a Reynolds number of 3×104 are illustrated in the form of a contour map. Moreover, the mean quantities characterizing the turning flow, such as deviation of the primary flow and the intensity of turbulence, are shown in a graphic form against the longitudinal distances. Simultaneously, discussions are given on the transition of phenomena in the longitudinal direction.

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An experimental study has been made of the stably stratified flow over three-dimensional ridges with isosceles triangle sections. The experiments were performed by towing models through saline-water solutions with linear density gradients. The ratios of the spanwise width of the model to its height have been changed between 2 and 6. Flow structures around models were visualized by means of the electrolytic precipitation method and tracer particles method. The velocity fields at several vertical cross sections were determined by PIV method. The Froude number Fr (=U0/Nh) was changed from 0.05 to 1.65 (and ∞), where U0 is the towing speed, N the Brunt-Vaisala frequency and h the height of models.
The structure of the flow over the ridge is characterized by the value of Fr. The value of the dividing-streamline height on the upstream side of the ridge has become a little small with increase of the aspect ratios for each value of Fr.

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In this research, the air flow of an air-conditioner is quantified and it is the purpose to save the energy by searching for an optimal conditions which are supply air velocity and angle. It experiments about the model room which diminished to one sixth toward the wall tapestry air-conditioner. A laser light sheet is irradiated for the supply air flow and is visualized. The general characteristic of an air flow is analyzed by the PIV method. The flow in the simple model room which without anything indoors was studied to the former. However, in actual room, various objects are placed indoors, and the influence cannot be disregarded. Then, by this report, two types of the objects is placed indoors and it compare with the simple model without an object. As the result, when an object is installed, it is understand that a flow diffused and it spread indoors.

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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. Presently, the simultaneous visualization and the velocity measurement have been carried out about the both phases of the liquid-liquid two-phase flow. The difference in the reflective indices makes the visualization in the vicinity of the boundary of the multiple phases almost impossible. In this study, the reflective index of the aqueous phase has been equalized to that of the oil phase by adjusting the concentration of aqueous solution. The results show the flow structure both inside and outside of a falling water droplet in the stationary oil simultaneously.

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In general, liquid spray field is a complicated and three-dimensional two-phase flow. The structure of it indicates strong correlation between size and velocity of droplets. In order to perform experimental analysis of the structure, simultaneous measurement of size and velocity of the individual droplet in the spray is the most important factor. In the recent years, the techniques based on IPI or ILIDS for the simultaneous measurement of droplet size and velocity were proposed as a field measurement technique, and the most of them are basically 2D measurement. However, multi-dimensional field measurement is indispensable for understanding of spray flow.
In this report, a technique of simultaneous measurement of size and 3D velocity of droplets based on the characteristic of light scattered from droplets has been proposed. In this technique, droplet size was estimated by glare-points separation, and 3D velocity was reconstructed with 3D PTV. The present technique has been applied to the measurement of spray issuing from the swirl nozzle. And its validity of velocity measurement was confirmed by comparison with the result of stereoscopic PIV.

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A vending machine is indispensable when we live comfortably. A former vending machine is used in this experiment. The air flow of the lower part in a vending machine was fundamentally visualized and analyzed by PIV. Especially upper side air flow of a shooter affects to cooling fluid in a can. The temperature of water in a can was measured and the cooling performance was compared. Consequently, the flow induced to the fan and the reduction of the flow velocity by the collision of the air flow to a shooter became problems. The shooter for preventing that the flow induced to the fan as improvement was processed (it is the blockade of one half of holes from the upper part). Attachment to a duct was tried in order to keep the wind velocity from a fan. By these improvement, the cold air current in a vending machine became energy saving.

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For global warming prevention, energy saving is called for also at the supermarket or the convenience store. In this research, the visualization model of the same size as the system and form was manufactured. It changed and experimented in internal and external double air curtain velocity. The Ar+ laser light sheet was illuminated from the front of a showcase, and the flow in an air curtain and a shelf space was visualized with using dry ice mist for the tracer. PIV was used for the analysis of a flow. The swirl in a leakage and shelf space of an air curtain wore evaluated synthetically. As a result, the air curtain leakage has been reduced by making inner side wind velocity increase. Inflow on the shelf of the upper row of an air curtain was one of the causes of a leakage. It became clear that the conditions of the air curtain of a system are satisfactory.

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The dynamic particle image velocimetry (PIV) is consisted of a high frequency pulse laser, high speed cameras and a timing controller. This high speed camera is able to capture 1k×1k pixels images at 2 kHz and 512×512 pixels images at 6 kHz. The three velocity components of flow downstream of an axial flow fan for PC cooling system are measured using the stereoscopic dynamic PIV system. An axial flow fan has seven blades of 72 mm in diameter. The rotating speed is 1800 rpm. The downstream flow is visualized by particles of about 0.3-1μm in diameter. The three-dimensional instantaneous velocity fields are measured at several downstream planes. The effect of the support of hub on axial velocity component is recognized by the instantaneous and time-mean vector maps.

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Hard-disk drives are the most popular storage devices in modern PCs. Recently, for higher speed and higher capacity, the accurate positioning operation of read/write magnetic heads becomes required. As the inside flow often causes pressure and velocity fluctuations, more accurate research have been needed. Our present interest is the flow between two disks. Namely, we consider a pair of disks of the same radius in a stationary cylindrical enclosure. Disks are connected with a common shaft, and corotate. Such a flow is often non-axisymmetric, and consists of two regions, that is, the region in solid-body rotation and the region of secondary flow. Until now, various studies have been carried out in order to resolve the flow. The authors attempt flow and thermo visualizations on a real HDD. Thermo visualizations show no obvious increase of disk-surface temperature during first 60[min.]. We confirm the existence of the solid-rotation core with some obstructed flows. But, there is no core at higher brockage ratio of the obstruction.

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The purpose of this research is to clarify generation mechanism of aerodynamic force of flapping airfoil imitating insect's flight. Hovering flights are important to develop micro air vehicles (MAV) for rescue inquiry devices of disaster area. In order to understand hovering flight of insects, aerodynamic lifting force and flow field around a flapping machine was measured by using PIV and numerical simulation. PIV measurements were carried out with the flapping machine which was 10 times expanding model of real insects. Experimental results showed a flapping-airfoil holds a strong vorticity near the bottom dead center. The wake-capture process can be observed by the PIV measurement, which is important to understand insect's flight. Moreover these processes generate large amount of aerodynamic force compare to the sinusoidal flapping motion. It reveals that feathering motion is important to realize the hovering flight.

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The aim of this investigation is to develop the high performance vertical axis wind turbine (VAWT) with turbulence promoters. An angle of attack of turbine blades in VAWT changes from a plus to a minus broadly. Symmetric vortex generators are therefore required to develop the turbulence promoters for VAWT. A thin tripping wire introduces at upstream stagnation point as symmetric turbulence promoters. In order to evaluate an effect of the turbulence promoters, wind tunnel experiments and numerical simulations were carried out. As a result, turbulence promoter restrains the flow separation at high angle of attack. Lifting force is 38 % larger than that of conventional airfoil by using the turbulence promoter. It reveals that the turbulence promoter is effective device to improve performance of the VAWT.

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Many studies on unsteady flow behind an unsteady airfoil have been carried out with experimental and numerical approaches. However, the detailed vortex structure has not been understood sufficiently. In order to clarify the quantitative vortex structure behind unsteady airfoils, such as pitching and heaving airfoils, at low Reynolds number region, we have carried out the PIV measurement at Re=4000. Moreover, we have performed the dynamic thrust measurement. The jet behind pitching and heaving airfoils in the wake increases as the non-dimensional trailing edge velocity and non-dimensional heaving velocity increases. As a result, the dynamic thrust acting on them became larger.

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The unsteady flow field within an annular turbine rotor was investigated experimentally using an LDV system. Detailed measurements of the time-averaged and time-dependent distributions of the velocity, the flow angle, and the turbulence intensity were carried out at a very low Reynolds number condition, Re, out=3.60×10⁴ . The obtained data was analyzed from the viewpoints of both absolute (stationary) frame of reference and relative (rotating) frame of reference. The effect of the turbine nozzle wake and secondary vortices on the flow field inside the rotor passage was clearly captured. The nozzle wake and secondary vortices are suddenly distorted at the rotor inlet, because of the three-dimensional distributions of velocity and flow angle around the rotor. The nozzle flow (wake and secondary vortices) and rotor flow (separation, wake, secondary vortices, and tip leakage vortex) interact intensively near the rotor exit.

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Digital engineering has been utilized in product development to improve the quality. The actual object was measured and digitized into the three-dimensional (3-D) data, and the requirement of evaluating and analyzing the CAD data has been increased in these activities. So, we developed the technology that measures the actual object and obtains the 3-D model data for general automotive parts. The features of this new system are high-speed and high-accuracy by using high energy X-ray CT technology and 3-D model data technology. 3-D model data can be obtained for about 5 hours in case of the engine block and the error is 0.1mm or less. We also show the examples of the new automotive parts development using this technology.

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This paper proposes a new approach to three-dimensional reconstruction of an object shape using multiple silhouette images that are taken from arbitrary random angles. The technique can be realized by utilizing a magnetic sensor that is attached to the CCD camera. The distinctive feature of this system is that it reduces the limitation of the target in terms of size, shape and obstruction, etc. but more importantly it reduces the dead-angle problem of measurement. Experimental results show the feasibility of our system.

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In this paper, we aim at visualizing smoke-filled space in front of fire crews using millimetric wave radar sensor. Our proposed system is composed of the millimetric-wave radar, a stereo camera, and gyroscope sensor attached on them. Millimetric-wave has a property of filtering out smoke. The FM-CW millimetric-wave radar can output a 2D reflection density values from obstacles for one-time scanning in invisible space. As for visible space by eyesight, we utilize the 3D stereo camera which can capture a 3D distance map with color information in an angular field of view. Both of the sensors have the capable of real-time scanning (10 frames/sec), and we manually operate them to scan target space. The scanned frame data is stored with 3D direction information from a gyroscope sensor. To construct the 3D space map, we integrate the 2D maps from the millimetric-wave radar and the 3D maps from the stereo camera using the gyroscope data.

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Three-dimensional unsteady behaviors of a supersonic cavity flow are investigated by the numerical simulation based on the Navier-Stokes equations. The resulting time-dependent solutions are phase-averaged on a dominant frequency. As a result, the standing wave in the cavity and vortex shedding from the leading edge are found to be highly three-dimensional.

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Understanding of hypersonic viscous interaction phenomenon over control surfaces and engine intakes is of particular importance for designers of hypersonic vehicles. However, experimental data of velocity fields around the compression corner which is an idealized configuration of these practical situations are sparse chiefly because it is difficult to obtain such data owing to short duration, high velocity, and rarefaction of the test flow in hypersonic ground facilities. In this report, we shall try to apply the high frequency impulsive glow discharge technique to obtaining the hypersonic velocity fields. The experiment is carried out in a hypersonic gun tunnel at Mach number 10 and Reynolds number based on the frontal plate chord length 2.8×10⁵. Time lines are obtained successfully, even for separated flow cases.

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It was necessary to analyze the finite amplitude waves in exhaust systems for prediction the acoustic characteristics in silencers of internal combustion engines. In this paper, according to the same calculation method to the previous work, a numerical analysis of the propagation of shock waves was carried out by using several silencer models with the internal structures which are comparatively simple. Two-dimensional analysis was compared with three-dimensional analysis under the same conditions by the silencer models of two-dimensional models and three-dimensional models. In addition, the effect of the reduction of the shock wave is considered by analysis of the model similar to the figure of the actual silencer.

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It is very meaningful that the Coanda effect is one of the characters of the jet flow, which clarifies the structure and behavior from the viewpoint of technological application. Recently, the numerical analysis and the experiment have been studied for the subsonic flow, but almost have not been researched for the supersonic flow. Then, the jet flow was issued from an asymmetric nozzle with an oblique outlet, the structure of the Coanda effect of the supersonic flow along curved surface wall was clarified, and the process where the Coanda effect was caused by the numerical analysis was clarified in this research too. As a result, it was able to be confirmed that the experiment and the numerical analysis were corresponding well. In addition, the Coanda effect of a supersonic flow through the numerical analysis was studied.

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The Hopfield neural network was already applied with success to the particle pairing process by the present authors. However it was limited to the frame pairs with relatively less number of particles due to its high computation time. In the present study the algorithm has been improved for reduced computation time. The point of the improved algorithm is new concept in connection scheme of the neurons, according to which the network is reduced from fully connected to partially connected scheme. The constrained conditions for the object function are further modified in order to meet with this new strategy. As a result the algorithm is able to handle the higher number of particles with higher degree of particle pairing accuracy within much shorter computation time. The algorithm is tested by using the PIV Standard Image of the Visualization Society of Japan,

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So far, visualization methods and the parameters are selected based on the reseacher experiences and his favor. We propose the effective combination of visualization methods and the parameters can be defined for the purpose from the view point of the human recognition. In this paper, we report our test method and the result to measure the recongnition difference between shading contour and line contour. As the result, we got the response time of shading contour was shorter than one of line contour. However, we did not get the difference of the correct answer raito.

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In the present study, we construct the 3-D data analysis environment for space plasma simulations such as Global MHD simulations, hybrid simulations and full particle simulations. This analysis environment works on a 3-D visualization tool, Application Visualization System; AVS/Express. It provides Earth and Space researchers with research environment to achieve new scientific findings.

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In the present study, we succeeded in improving an oil hydraulic ball valve using the visualization technique, in order to prevent the vibration, cavitation and the noise of the ball valve. The valve body outside of the ball is made of transparent acrylic resin to observe the flow and the motion of the ball. The cavitation cloud near the orifice in the valve, and the movements of the ball, the ball support and the spring during cavitation and the vibration of the ball are observed using a commercially available digital video camera, a high-speed video camera and X-rays. After the generation of the cavitation and the vibration of the ball inside the conventional ball valve are visualied in detail, new types of the ball valve without the lateral oscillation are designed to obtain good performance. It is confirmed that one of the new types of the valve has no cavitation bubble and no cavitation noise. Furthermore the upstream pressure of the valve is measured and discussed from the vibration point of view.

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The effects of the inlet casing configurations on unsteady cavitation were examined with a 3-bladed inducer. The inlet flow and cavitation pattern with two casings were visualized using by PIV and high-speed video. It was found that the rotating cavitation would be suppressed when the tip clearance at the inducer inlet was increased. The vortex cavitation in tip leakage flow and cavitation in back flow effected the suppression of the rotating cavitation through the inlet casing configuration.

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A stable plasma within cavitation bubble created in a liquid can be achieved by applying microwave and ultrasonic irradiation simultaneously. We refer to the latter plasma using ultrasonic vibration as sono-plasma. We propose that plasma in a liquid be applied as a new technique to replace the gas-phase. To control the plasma for practical application, it is important to clarify the behavior of bubbles in liquid. The behavior of a single air bubble in water, n-dodecane and benzene with ultrasound was visualized by use of stroboscope, and calculated by numerical simulation. Single bubble sonoluminescence was observed in the case of using water. However the luminescence phenomenon was not observed in liquid hydrocarbon. When the bubble size is minimum, the deformation of the spherical bubble occured in liquid hydrocarbon. Ultrasonic wave had to be irradiated with much lower amplitude of sound pressure than that in water to hold the bubble, which moved and became unstable with increased of sound pressure. The numerical analysis results are compared with that of the observation data to check the reliability of the analysis.

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To investigate the movement of each bubble individually, we attempt a 3D PTV analysis of air bubbles. A compressor blows air into water in a 1m×1m×1m cubic tank through a converging nozzle with an inner diameter of 0.3[mm]. The pressure p 0 of a chamber between the compressor and the nozzle is 1.0×10⁵, 2.0×10⁵ or 0.1×10⁵ [Pa]. We take the stereo pictures, using two high-speed cameras. Choked and non-choked conditions are compared.

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To improve the combustion efficiency in a direct injection engine, it is important to improve the mixture formation on the combustion chamber wall. In the gas injection in the atmosphere flow is high-speed and analysis is difficult. Then, the jet is changed into the low-speed liquid injection in liquid by the similarity rule of a flow. The influence by the angle of a plate (modeled the piston head) analyzed the concentration characteristic of an unsteady impinging jet with the photograph visualized by the laser light sheet method of Ar+. Understood the process of development of the unsteady jet by after injection start. Development of the unsteady jet by the difference in the angle of plate was also observed. It becomes a clue in a solution to the trade-off of NOx and soot from the concentration character of unsteady impinging jet.

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Explanation of injected fuel and air mixture formation process in combustion chamber is necessary to reduce exhaust gas of a car. The shape of fuel jet is shown quantitatively by fractal dimension. And the unsteady jet shape characteristic is clarified. Till now, helium jet has been visualized by the Schilieren method. By this method, the three dimensional data on a jet is photography in two dimensions, and it cannot extract only the outline of a jet. So water jet with tracer is injected into a water, and the two dimensional section of a jet was visualized by the laser light sheet method. The photograph of jet is taken by high speed camera. The outline of jet was extracted by image processing. The jet shape characteristic was found by searching for a fractal dimension. And it becomes clear that the jet shape characteristic changes with differences in nozzle shape (diameter and length).

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As a part of the investigation on the control of jet diffusion, the flow visualization of jet has been conducted. The jet issues from the pipe exit where the soft fins made of an artificial cellulose are attached. By using the experimental results from the PIV method, the jet width has been obtained. Moreover, the wavelet multi-resolution analysis has been carried out, by using the images from the LIF methods. As a result, it has been found that the fluttering fin affected the jet diffusion largely and this effect appeared remarkably in case of a long fluttering fin. Furthermore, the difference of the flow structure between the jet flow with and without fluttering fins is recognized from the results of the wavelet multi-resolution analysis.

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The relation of the vortical structure and the entrainment in the initial region of a plane jet was investigated under the four conditions of vortex generators by vorticity measurements. The vortices were enhanced and stabilized by streamwise and spanwise disturbances. The three-dimensional views of the vortices were constructed by applying the Taylor hypothesis to the phase-average vorticities, and the entrainment was discussed in relation to the vortical structures. The result reveals the enhancement of entrainment by the interaction of spanwise and streamwise vortices

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The Gortler vortices on a concave wall of the three-dimensional convergent nozzle. having rectangular cross section were affected by crossflow in boundary layer with difference of static pressure. Flow visualization by means of smoke-wire technique and hot-wire measurement with I-type probe were carried out for main airstream of 1.5m/s. Using the two-dimensional convergent nozzle and the three-dimensional convergent nozzle, the Gortler vortices transformed remarkably in boundary layer by the crossflow on the curved wall were observed.

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Recently in nuclear plants, it has occurred thermal fatigue failure accidents because of thermal fluctuations that called Thermal Striping in T-junction where mixed a higher temperature sodium and a colder temperature sodium into each other. Then, we set up turbulence promoter in T-junction piping system, effects of turbulence promoter on flow characteristics have been investigated experimentally using flow visualization techniques (the dye injection method) and velocity measurement by LDV. As a result, it is clarified that secondary streams in pipe sections becomes stronger and diffusion of momentum is promoted in case with turbulent promoter.

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The three dimensional visualization is an important method to understand the flow structure. In this study, the program that can pursue a motion of arbitrary two or more passivity particles is constructed for the Taylor-Couette flow with small aspect ratio. It can visualize a flow field in three dimensions. The inner cylinder is rotating whereas the outer cylinder and the end wall of cylinders are stationary. The velocity data that is in the quasi-steady state after fully developed flows are used. Using the staggered grid, the an algorithm of interpolation method in three dimensions is developed and we succeeded to pursue a fluid particle. A user can change a starting position of a particle, time interval, velocity data, iteration number and the circumferential velocity component. After drawing path lines, the user can change a point of view with mouse operation.

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We developed a system for analyzing and visualizing business solutions provided by information technology (IT) companies in Japan. The system enables analyzing investments in the IT sector in Japan that exceed 100 billion dollars per year. The system uses information about business solutions obtained from web sites to do the analysis. It generates a two-dimensional diagram of the information using a visualization engine called GAVE (Galaxy Analysis and Visualization Engine). The system enables analyzing IT investments by year, company size, industry, characteristics of the region, and so on. It enables users to understand how IT investments are being made in Japan. The IT industry is growing rapidly, and opportunities for investment can significantly affect the cost of the investment. Companies making investments in IT can use this system to make informed investment decisions to ensure their competitiveness.

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The 3D visualization of observation data and the result of simulation becomes the useful analysis method recently. And by sharing the processed data between fellow researchers, we may have common view simultaneously and improve mutual understanding. So we realized the importance of the development of the middle-ware that supports the bi-directional and multipoint communication with 3D visualization tools. As we had been built VEMS (Virtual Earth Magnetosphere System) on AVS/Express (Application Visualization System), we developed the distributed object based middleware 'Milkyway' to act in union with them. It realized that the multipoint and bi-directional communication accelerates the understandings and helped the enlightenment of the new aspect from the modeled data.

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We have constructed a new research environment for Earth and space science based on virtual reality system and network database: a Virtual Earth Magnetosphere System (VEMS). The VEMS provides an interactive research environment by which researchers can visually understand structure and dynamics of Earth magnetosphere. On the VEMS, data assimilation, combinations of computer simulation and observation data, is possible. Since the VEMS deals with time-dependent data, it helps researches to understand temporal and spatial structure and behavior of the magnetosphere. More realistic data analysis is possible using VEMS on CAVE.

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A newly developed visual-oriented numerical method for solving the two-dimensional unsteady-state heat conduction problem which applies the spreadsheet of Excel is explained through a simple physical model. The present unsteady-state numerical calculation has been realized by introducing a dummy sheet with empty cells and a sheet with icon cells, in which difference equations concerning the inner, boundary and singular points and so on are embedded. By organizing and expanding such sorts of icon cells, the proposed method is expected to get applied against much wider range of heat transfer problems in the future.

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The turbulence characteristics in the Rayleigh-Bernard convection of horizontal fluid layer are quantitatively evaluated using thermo-sensitive liquid crystal particles suspended in a fluid. The temperatures are evaluated from the color change of liquid crystal particles using HSI calibration technique and the velocities are evaluated from the PIV analysis of the intensity images. The results are shown by the distributions of temperature, the fluctuating temperature and velocities, which allow the evaluation of statistical properties in the Rayleigh-Bernard convection.

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In the observation of thermocapillary flow using a molten metal which is an opaque low Prandtl number fluid, the internal flow pattern has to be estimated from the fluctuation pattern of the surface temperature. In order to obtain the internal flow pattern directly, the visualization technique using an ultrasonic wave has been developed. The position of a tracer can be detected by small array transducer, and the internal flow pattern can be visualized from dynamic position change of the tracers. The tracer and signal processing equipment which is used for an actual flow examination were manufactured, and these were checked satisfying a required function by the test. Moreover, the numerical simulation was performed to verify the capability of this system.

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This paper present the visualization of refrigerant flow for falling film type evaporator on enhanced tube. The enhanced tube on external surface has independent projections with a projection pitch of 26 fins per inch, and a circumferential segmentation pitches of 0.53 were tested. The observation of refrigerant flow was carried out at the evaporation pressure of 0.8kPa, at the outlet chilled water temperature of 7 °C, and at the refrigerant flow rate per unit length between 0.75 and 2.00 kg/(min m). Refrigerant flow was also photographed the top of the tube at a frames rate of 500 frame per second using a high-speed video camera. The results of the study showed that a thin film refrigerant film formed on the grooves as the refrigerant flow rate decreased.

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The assist of respiration for the premature babies based on nasal CPAP (Continuous Positive Airway Pressure) is one of the important medical treatments. Some devices of nasal CPAP have been developed, however they give some kinds of installation load to the babies. In order to decrease the load, the down sizing of the devices and the improvement of the installation method are required. A new type device of nasal CPAP has been developed for adapting these requirements. The device operates fluid-dynamically in switching mode of jet flow by the similar mechanism of a fluidics device. The fundamental characteristics in fluid dynamics have been investigated experimentally by using techniques of qualitative and quantitative visualization.

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This paper aims to investigate behavior of pulsatile blood flow in a curved pipe that emulates the Internal Carotid Artery (ICA), which is the frequent occurrence site of an aneurysm. Due to the limit of in vivo experiment, the PIV (Particle Image Velocimetry) is applied to obtain detailed flow information such as complicated secondary flow created by curvature of in vitro experiment. However, the blood flow in the artery is pulsatile, and time-resolution of the conventional PIV is not enough to capture transient behavior of pulsatile flow. Thus, the dynamic PIV is applied to measure unsteady flow. Since the dynamic PIV can provide good resolution in space as well as in time.
As a result of measurement, even with the same Reynolds number, flow characteristics at systole are drastically different from those at diastole. Especially at the time of diastole, the large recirculation flow, which is not seen in steady flow, is observed in the separation region. The secondary flow in the cross section changes according to changes of flow rate in time.

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