A simple wake survey method was applied to the flow fields after an airplane model and a passenger car model. The method consists of a rake of four simple total pressure probes, a traverse mechanism and a personal computer. The measurement can be automatically conducted by their combination.
The model airplane is of FA-200 of Fuji Heavy Industries and the car model is of Supra of Toyota Motor. The measurements are made at various conditions changing flap angles, angles of attack. In case of the car, yaw angles were changed and the body shapes were changed into fastback, squareback and wagon by changing several attachments.
The obtained results were compared with the aerodynamic forces measured by a struttype balance and presented good explanation of the measured aerodynamic forces.

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The three-dimensional vortical structure of a circular water jet was investigated by a flow visualization technique. The jet was excited by axial and azimuthal perturbations to stabilize and enhance axisymmetric and streamwise vortices. A laser florescent dye and a laser light sheet were used to visualize the jet. The three-dimensional view of vortical structure was constructed by applying the Taylor hypothesis to the jet cross-sectional images. The view reveals the details of the complicated structure. From the three-dimensional view, the area of jet boundary surface was estimated to discuss jet mixing. The result suggests that the enhancement of axisymmetric and streamwise vortices is very effective to increase mixing.

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Seawater tends to stratify because the sea surface is high temperature and the bottom is low temperature. Upper seawater with large amount of planktons and lower seawater of large amount of nutrient salts are mixed around this density stratified boundary by discharging the mixed water horizontally. So similar to the water flowed on a flat plate in the air, the flowing mixed water will follow the interfacial boundary. The flow entraining makes it possible to agitate large areas. This experimental investigation has been observed the behavior by changing saline density in a two-dimensional tank as the basic experiment of previous phenomenon, making the density stratified layers and jetting colored water from a nozzle. The sprayed water jet diffuses horizontally in the stratified layers according to that density. We have observed interesting behavior when water is sprayed in the different density layers. At first it diffuses up and down to reach the layer of same density as itself, then diffuses horizontally.

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This paper is concerned with the water circular jet flow issuing along the circular cylinder wall. Especially, attention is focused on the flow aspect in the cross section normal to the jet flow. This flow aspect at several down-stream locations has been visualized by the system composed of the dual-pulse YAG-laser, the CCD-camera, the CRV and the PIV. The visualized image information has been compared with the experimental results obtained by the hot-wire anemometer system, which have been already presented in the previous paper. As a result, the interesting flow aspect obtained from the velocity contour maps in the previous experiment has been explained by using this image processing results.

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In order to reveal the intermittent phenomenon of circular wall jet issuing along cylinder over a time and frequency region, the wavelet cross spectrum was used to analyze the experimental velocity signals between two different fluctuating velocity components. From the wavelet cross spectrum analysis, the instantaneous contribution to Reynolds stress may be easily analyzed. The flow structure of the circular wall jet has been clarified using the wavelet cross spectrum method, comparing with that of the plane wall jet.

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For the purpose of simulating diffusion flames, the authors make an experiment that a small amount of Sodium Hydroxide Solution (NaOH) is injected into water bath with Hydrochloric Acid (HCl) and observe acid-base neutralization using Phenolphtalein. The paper presents a concept of analogy between diffusion flames and liquid jets using acid-base neutralization and a plan of the system. The observation results shows that the reaction and diffusion process of acid-base neutralization is the same as that of diffusion flame except the point of being magnified in time scale. And this observation measure is one of the effective method to analysis of reaction and diffusion process.

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This paper presents the result of an experimental study on a reattachment of a radial turbulent jet discharged from a cylindrical nozzle onto an adjacent disk plate. The flow on the side wall are visualized by oil film and surface tuft methods, and the velocity field near the wall (forward flow fraction, power spectra and time-space correlations of the fluctuating velocity) are measured by hot-wire probes. The reattachment positions are distributed concentrically and the flow is axisymmetry. However, the flow around the reattachment positon periodically switches its direction relatively.

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The National Defense Academy, Dept. of Mechanicak Engineering, Hashirimizu 1-10-20, Yokosuka, 239-0811 Japan Experimental studies on the fluid flow around a small disk levitated by a circular impinging jet with confining wall were carried out. The diameters of the upper and lower disks were 100 mm and 2075 mm, respectively. The mass of the lower disk ranged from 0.77 to 52 g. The behavior of levitation of the disk and the pressure distributions on the disk were measured in the range of the space between the two disks from 0.5 to 6 mm. The flow rate was ranged from 10 to 50 limin. The surface oil-flow patterns on the both disks were visualized. The levitating and falling critical flow rates were obtained by the dimensionless quantities. And the dimensionless lift acting on the lower disk was also obtained. The lift is almost equal to the weight of the disk. The levitation of the lower disk was caused by the large pressure drop outward along the impinging region of the jet. The pressure drop was induced by the vena contracta due to the separation bubble attached on the upper disk.

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Feedback mechanism of self-sustained oscillation in impinging jets with M = 1.0 was studied experimentally by using a laser-induced fluorescence (LIF) technique. Phase velocities of disturbances in the flow field were obtained from a time-dependent cross-correlation function between a reference pressuresignal on the wall and the LIF signal in the flow field. A feature of disturbance propagation can be visualized by drawing maps for the cross-correlation coefficients on a plane at successive delay-times and making an animation. There are two feedback loops : one is closed by a neutral wave propagating upstream inside the jet and another is achieved by sound wave propagating outside the jet. Both the axisymmetic and helical modes of resonance were clearly observed by use of the present method.

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The color Doppler method, which can measure velocity of a flow in realtime using the Doppler effect of ultrasound, is suitable for observation of a blood flow and has contributed to diagnosis of circulatory illness. However, the result of measurement is represented as a 2-D image, which is not useful for understanding a state of a complex flow. This paper presents 3-D visualization methods of a blood flow from color Doppler images. For diagnosis and investigation, the visualization of a blood flow must fulfill the following features : (1) objectivity (2) interactivity and (3) multi-aspect. The proposed system meets the above requirements by providing realtime visualization methods and intuitive interfaces. Moreover, an experiment with a phantom channel shows that the proposed system enables observers to recognize a state of an entire flow, such as occurence of turbulence and an area of regurgitant jets.

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Particle image velocimetry (PIV) is a quantitative method of measuring velocity fields instantaneously in experimental fluid mechanics. In order to improve the dynamic range, resolution and accuracy, the authors has proposed a new high-resolution PIV technique based on iterative cross-correlation and gradient method. The proposed method has the error of the order of 0.01 pixels.
In this paper, the proposed method is applied to visualized images of the arteriole in the rat mesentery using the intravital-microscope and the high-speed digital video system. Time-series of the velocity profiles of the arteriole was obtained. Averaged velocity profiles shows the blood flow volume were constant at five vessel cross-sections. The arteriole velocity profile was blunt at center region of the vessel cross-section and sharp profiles at near wall region, this suggests the shear stress on the vessel wall is higher than expected. The results show that the proposed method is very useful to measure the blood flow velocity profiles with high accurate, temporal and spatial resolution.

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In the design and development of medical instrument, safety, functionality, derating to the patient, etc. are problems of the prime. In order to realize them, the engineering viewpoint is important factor. The problem concerning the fluid dynamics is often included in it, and improvement based on the detailed analysis has been required. Nasal continuous positive airway pressure equipment (Nasal CPAP) for newborn infant with respiration disorder using the principle of fluidics is one of the typical devices concerning the fluid dynamics. Nasal CPAP has been improved in order to reduce the burden to the newborn infant. However, the optimization of the shape does not advance for the improvement on the operating condition, and it limits the movement of the newborn infant in the mounting. With the aim of the miniaturization of the equipment a simple model of it using at present is made, and by the examining characteristics by the visualization of internal flow, the directivity of future improvement is examined.

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The purpose of this study is to analyze the mechanism of a small insect's wing to make the micro machine which is able to move and fly everywhere in three dimensional area. We investigate the structure of small insects and take photographs of the insects, which are Aulacophora nigripennis and Harmonic axyridis, by using the high speed video camera. Then we obtained the locus of the wings, and the following three flapping parameters; the flapping angle, the period and the velocity. After all we reach the conclusions as follows; 1) The upper wing moves simulateneously with the wing. 2) The Aulacophora nigripennis and Harmonia axyridis have similar posture in flying. From these consequences, we know the mechanism which is suitable for the body size of small insects.

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An experimental study on visualization of the wave profile is presented here. A diode-pumped solid-state laser was used as a light source for exciting fluorescent dye (Rhodamine-B). The combination of a high speed CCD camera and two sliding rails were used. The sliding rails were used to move the CCD camera and an optical projection unit with propagating wave crest. Specially, we perceived region between breaking and non-breaking wave on a constant depth reef. As a result, microscale breaking wave, which has no falling jet at breaking process, existed in the boundary region. The breaking wave decayed through the capillary waves progressed to 3D turbulence without the jet plunged.

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The Sea of Okhotsk is well known as one of the southernmost seasonal pack-ice zones in the Northern Hemisphere. The pack ice are observing with three radar stations in Esasi, Mombetsu and Abashiri These radars were constructed by Sea Ice Research Laboratory (SIRL) of Institute of Low Temperature Science, Hokkaido University. The pack ice floe is very complex because of having various factors. Therefore, there are many sea accidents in the coast of Okhotsk Sea during the sea-ice season. To avoid these accidents, it is necessary to need some information regarding the movement of the ice pack. However, the radar image is the static information that has the scale and position of the ice pack. There is no information regarding the movement of the ice pack. This paper describes the visualization of the pack ice flow on the Okhotsk Sea with a PIV technique, using a series of radar image that is taken automatically every 3 hours with a computer.

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Diversified analysis of end-use energy consumption is indispensable for exploration of desirable energy system in urban area. This paper proposes a VR-based interactive visualization system utilizing hyperlink function of VRML. The proposed visualization relates end-use energy consumption with consumers' geometrical arrangements and nests sets of visualizations of different spatial resolutions. The users can traverse the set of visualizations and can observe them in a virtual environment. The proposed system is applied to a set of end-use electric power consumption data of a certain area. Experimental results clear that the visualization lets users comprehend a trend of end-user and characteristics of each consumer.

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The purpose of this study is to evaluate the pedestrian space with time series interfering area model. The model illustrates the interference of pedestrian's area in the several directions. And the coordinates of pedestrians are sensed and used for evaluation of the space. The “time series interfering area model” describes the load between pedestrians in the several directions. This model's advantage is as follows; (1) The characteristics of pedestrian loads in a time series are grasped and comprehended with it. (2) As the congestion in the observation area in a time series is observed, and the area is evaluated particularly. (3) The situations of intersecting pedestrians in the several directions are grasped.

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Creatures, such as humans, fishes or birds move in a cluster or crowd almost always. The characteristics of crowd motion were discussed from the point of fluid dynamical view. The motivation of its motion was classified into 7 categories due to the intelectual level. In the present report, lowest three categories were taken into consideration. In order to express an individual molecular potential, a poly-nominal potential function was discussed and introduced for human model. Directional and influence functions in the dynamics of collision were introduced to take account for the dependency of view angle of creatures. Thermo-dynamical macro quantity such as temperature, pressure and density were defined for the creature flow. Simple models of collision of two individuals and of cross flow between two crowds were simulated by using the present technique.

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The purpose of this study is to analyze the patterns of complicated pedestrian flow with visible pedestrian area model. The coordinates of all pedestrians at each frame is calculated.The pedestrian area is defined as the 90cm circle from the coordinates of each pedestrian. The condition of monodirectional pedestrians which forms groups is similar to the distribution of electric field, so Blobs, Meta-ball, with Bezier Clipping method is used to visualize the pedestrian area. (1) The conflict among pedestrians is reduced by the forming group of monodirectional pedestrians; (2) The pedestrian move along the edge of other group's area because he/she can't cross inside the group; (3) The overlap of group's area illustrates the conflict between groups;The condition of pedestrian flow is analyzed with visible pedestrian area model.

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The CFD prediction of temperature and ventilation performance in an Automobile-Headlamp is very helpful to design a new type of headlamp casing. In the previous Paper, the CFD calculation in the Headlamp are presented using skelton model. Then it is found that the acuuracy of the prediction is well improved by applying PIV measurements for determination of the CFD boundary condition. In this paper, new developed technique called SHT was investigated with PIV measurements and temperature measurements. Consequently, temperature results by CFD were within ±10° as compared with experimental results.

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Recently with improving high-speed performance of vehicle, the wiper characteristics can not be performed enough because the wiper lift acting on the wiper blade decrease pressure force of the wiper blade on the windshield. The fin attached to the wiper blade is the most affective method to increase pressure force of the wiper blade on windshield.
However the studies on influence of the fin on wiper characteristics can not be almost found. So, we tried to clear influence of specifications of the fin and attached conditions of the fin to the wiper blade on flow pattern through the wiper blade by experiments. As the result, we can find the most optimum specification of the fin and attached condition of the fin to the wiper blade by observation of visualized flow pattern.

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In this report, in order to evaluate influence of eccentricity on the behaviour of Taylor vortices in submerged multi-pad journal bearings, fluid film flow in bearing clearance and cavity flow between pads were visualized by means of tracer method. Critical Taylor number decreased once, and then increased with an increase of eccentricity as in the case of full cylinder.

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Research results pertinent to heat exchangers are available in existing literature and heat transfer text books. However, it was short of sufficient flow visualizations in louver fins because of the difficulty in its flow visualization. Flow visualization by means of the dye injection method and the laser Doppler velocimetry (LDV) was performed to disclose flow characteristics in louver fins. Three kinds of louver angles of θ=10°, 15° and 20° were tested. Flow patterns in each louver fins are visualized using the fluorescein dye illuminated a laser light sheet. The LDV data were used to calculate Reynolds stress distributions and power spectrum distributions. It is disclosed that flows in cases of θ =15° and 20° exhibit a distinctive periodic characteristics, and the Strouhal number is uniquely related to the Reynolds number.

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This paper describes water flow characteristics and heat transfer characteristics of inclined fintube heat exchanger. In order to demonstrate the fundamental performance of water flow visibility experiments are done. Concerning to the heat transfer characteristic experiments of different lean angle are done and the result shows that both the heat transfer rate and the flow loss are increased according to the increase in the inclined angle. Moreover, no matter what inclined angle is the heat transfer rate is a bit higher than the normal one.

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Flow structure and heat/mass transfer characteristics for turbulent flow in serpentine channels with a inclined partition wall have been examined experimentally. Detailed distributions of velocity data have been measured using PIV for three kinds of angle α=+4°, 0°, -4° at Reynolds number of 3.5×10⁴. Next, by comparing the published local mass transfer results for their three cases, the mechanism of the heat (mass) transfer from the channel wall in and after turn section were discussed.

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There are many kinds of branch pipes connecting to the main coolant pipes of nuclear plants. Some of them are closed with valves during normal operation of the plants, and form deep cavities. The flow in the main pipes induces cavity flow in the branch pipes. Cavity flow and heat radiation form a thermal stratification in the pipe. We observed the structure of the cavity flow in a branch pipe with a closed end, and found there are one or two cellular vortices near the branch and a spiral vortex beyond them. We measured the distribution of the tangential velocity of the spiral vortex to get an experimental equation. We also measured velocity and temperature distributions near a thermal stratification to get the local Richardson number. The cavity flow deeply goes into the branch pipe, and its length depends on the local Richardson number given by the decay of the tangential velocity and the stability of the stratification.

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The flow field in tube banks of a tube-nest combustor has a completed 3-D flow structure by the impingemeat of burner jet. This 3-D structure has significant influence on the heat transfer characteristics around the tube. The flow field near the boundary layer on the tube was visualized by the oil-lampblack method. The observed trace of oil indicated clearly a close relationship between the flow structure and the heat-transfer distributions.

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Universal motors are used in mainly cleaners. The commutating processes take place by sliding contact of commutator segment and brush, and sparks occur when a segment separates from the brush. The commutation sparks cause wear on the brush and electromagnetic interference to other electronic machines. We visualized images of sparks on high-revolving. motors by a high-speed camera, and analyzed the mechanism of the spark generation. We devised external laser triggering using laser light for shuttering of the camera. This method make it easier to analyze images because it provides with images of the same point of the same segment every time. By photographing spark generation with a high-speed camera by external laser triggering we probed that sparks occurred on every other segment and also visualized that commutation spark occurred on one segment.

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Much progress has been made in recent years in reducing the noise from air conditioner centrifugal blowers used in automobiles. There is particularly great demand to reduce the noise in the frequencies 50-300 Hz generated in the high-pressure operation area. Therefore, the mechanism by which the low-frequency noise is generated was analyzed and measures for reducing blower noise were studied.To analyze the noise generating mechanism, flow visualization and fluid measurement were used. The flow visualization method was to inject and adjust the tracer from two locations and clearly visualize the flow at the interference section, which was the cause of the noise. For fluid measurement, SI and a hot-wire flow velocity meter were used to investigate the relationship with the noise. It was found that the causes of the low-frequency noise are fluctuating flow and periodic vortex generation at the blower intake side.

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A study of internal centrifugal blower is very interest in case problems for improve the characteristics. Also, the form of volute tongue which have an affects to characteristics centrifugal blower. This paper is described about effect of tongue shape for characteristics of centrifugal blower. Visualized experiment and numerical calculation for the tongue shape of 3 types clarified the flow characteristic of the flow near the tongue in centrifugal blower. As the results, the following facts are made clear. The behavior of the flow near the tongue agrees with that obsessed by flow visualization experiments. Numbly the stagnation punt moves around the tongue when changing the mass flow.

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An advanced single-cylinder DI deisel engine for visualizing in-cylinder phenomena has been developed. The combustion chamber of this engine is optically acsessible from three directions of top, bottom, and side. Furthermore, a transparent glass part is set around the cavity on the top of the extended piston and thus in-cavity phenomena is also observed. In additon to direct photography and shadowgraphy from each direction, laser light sheet techniques such as laser-induced fluorescence (LIF) and laser-induced incandescence (LII) can be applied. For example, fuel vapor distributions in both cavity and squish areas have been clearly measured by using LIF imaging.

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We have developed a laser ultrasonic system for the visualization of elastic waves propagating on a solid surface. Scanning an optical heterodyne probe to measure surface transient displacements, ultrasonic waves in the frequency range up to 50MHz are detected and passed to a personal computer through a digital oscilloscope. The recorded signals are reconstructed to make 3-D displacement images at any propagation time. This system can produce a series of successive images as an animation of wave propagation. Using this visualization technique, we observed the scattering and diffraction of ultrasonic waves around various shapes of simulated defects, and examined its application to nondestructive inspection

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We thought that the luminescent spot was related to the continuation of the electrical discharge. In this study, we aimed to know the relation between stability of electrical discharge and behavior of luminescent spot. The chamber is made of the stainless steel of 150mm in the diameter and 200mm in length. The anode is a cylinder (Ti 99, 9%), and the diameter is 5mm. The cathode is a disk (Ti 99.9%), and the diameter is 50mm. The helium gas (99.99%) was made an atmosphere gas and the arc was discharged from 0.1Torr to 2Torr. The behavior of the luminescent spot on the electrode was observed, and the relation to the continuation of arc discharge was considered. In the current that the electrical discharge is maintained to stability, the cathode luminescent spot was observed to move continuously.

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The electrorehorogical (ER) effect is known as a phenomenon that shows reversible increase of apparent viscosity by applied electric field. The electric field induces the particle polarization, resulting in the chains between the electrodes.
In this study, the ER fluids in the channel with two parallel electrodes were visualized under the pressure flow and the constant flow rate. The laser light sheet and transparent electrodes were used in the experimental apparatus to visualize the particles under lOwt% concentration. The particle chain structure in the channel was clearly visualized. Under higher voltage condition, particle layers were formed at the neighbor of the electrodes. The layer gradually becomes thick, at last it is destroied. By compareing the visualized image and the mass flow rate, the relation between the layer and the mass flow rate were investigated.

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A fast and effective algorithm for particle detection is presented. In this method, correlation between a simple 1-dimensional function and image intensity is evaluated and binarized to detect particles. It is found that the calculation time of the present method takes less than 0.3 times of particle mask method, and the number of extracted particles by present method is about 1.5 times as that by standard binarization method.

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An improved correlation based Particle Tracking Velocimetry (PTV) algorithm was proposed in the present paper. The path tracking of the tracer particles was achieved through a recursive correlation operation of the small interrogation window at two-time steps. The central positions of the tracer particles were determined by the correlation operation of the tracer particle image with a gauss particle mask in order to improve the accuracy to identify the central positions of particles up to sub-pixel level. The performance of the present improved correlation based Particle Tracking Velocimetry (PTV) algorithm was evaluated by using both artifical VSJ standard PIV images and actual PIV images of a self-induced sloshing. Compared with other conventional PTV methods, the present improved correlation based PTV algorithm was found to be able to provide better solution.

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In order to improve the dynamic range, spatial resolution and measurement accuracy, a number of iterative methods have been proposed. In these methods, the three-point Gaussian peak fit of correlation value is usually used for a sub-pixel analysis. However, it is reported that the root-mean-square (RMS) error is no less than 0.1 pixels because of simple courve fitting concept, and that it requires high particle concentration or the large correlation window.
The authors have proposed the high-resolution PIV technique based on the crosscorrelation and the gradient method. In this paper, the sub-pixel displacement in the proposed technique is obtained using the spatio-temporal derivative method instead of the three-point Gaussian peak fit. The error of the proposed technique is analytically evaluated as the function of sub-pixel displacement, the particle image density and the out-of-plane displacement using Monte Carlo simulations. It is confirmed that the present method shows the higher performance both on the accuracy and the special resolution than the Gaussian fit method, and its RMS error is in the order of 1/100 pixels.

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Conventional PIV method in which cross correlation coefficient is used has problem that erroneous vectors occur considerably if the correlation matrix is reduced to raise the spatial resolution. In present algorithm, searching for image in correlation matrixes and dividing the matrix are iterated, and after that the second step image transforms to approximate to the first step by using obtained vectors. Shift vectors at each point are obtained by repeating these operation until satisfying necessary space resolution. It is possible to search directly for a position where a correlation coefficient indicates the maximum value, because the shift distance is always smaller than the correlation matrix size. This method is applied to the standard PIV images and the visualized images of wake behind a circular cylinder. And from the results of these PIV measurement, it made clear that initial number of image division must choose appropriate number to prevent emerging erroneous vectors.

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A new type of genetic algorithm (GA) has been developed and implemented for the use in the particle tracking velocimetry. High performance of particle tracking is achieved by introducing a new fitness function as well as by some new ideas in the selection, crossover and mutation operations. With this new algorithm, the GA-based particle tracking velocimetry is likely to attain optimal solutions more quickly and expected to be applied to PIV recordings with larger numbers of particles.

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A method of three-dimensional space reconstruction of particle streaks by genetic algorithms is proposed to progress in 3D PTV The reconstruction became a correspondence of a set of particle streaks observed on two camera capture directions. The genetic algorithms applied to the correspondence as an optimum combination process, and the labeled particle streaks encoded in the gene strength of genetic algorithms. The experimental inspection of this method was carried out for an example of numerical simulated particle flow images with 200 particle streaks. The algorithms and the experimental results are discussed in detail.

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Particle tracking velocimetry (PTV) is one of the methods that measure flow velocity fields. This paper proposes a new method that solves the correspondence problem of particle tracking velocimetry using a network model. The PTV offers many advantages for the study of fluid flows. The flow visualization images are analyzed to obtain the velocity distribution of the flow. Several PTV algorithm has been proposed in the past. The most of the method assumes that the fluid motion, within small regions of the flow fields, is parallel over short time intervals. However, actual flow fields may have some detoured motion, such as rotation and expansion. The proposed pairing particles method using the networks model is based on a connection of particles according as the weights between particles on a 1st image and 2nnd image. The technique is applied to the PTV standard images distributed through the web site (http : //www.vsior.jp/piv). The simulation results demonstrate the effectiveness of the present technique.

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In this study, high spatial resolution measurement technique for three-dimensinal velocity distributions was examined. The Holographic Particle Image Velocimetry (HPIV) was the technique to record the three-dimensional position of the tracer particle on the hologram. From the 3 dimensional holographic particle images 3 dimensional velocity distribution could be calculated whith high-spatial resolution. Ordinaly the HPIV use the Phase-conjugated configuration to reconstruct the 3 dimensional particl position. Though with the technique the particle locations could be obtained with high S/N ration and high spatial resolution, the technique had very complicated caribration procedure and sensitivity. Therefore, in this study using the virtual image, more simple extracting technique to reconstruct particle locations were examined. The technique were simple in lyaout and had good S/N ratio and spatial resolution. Using the holographic particle images, 3 dimensional velocity could be obtained with high accuracy. In the experiment, the technique were applyed to measure upword air jet. The 3 dimensional particle locations were well extracted. Using the extracted particl locations, the 3 dimensional velocity could be calculated well showing the effectiveness of the technique.

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It is difficult to grasp the whole flow field accurately by PIV, because the velocity vector is located at a wall surface is missing in most cases. In this study, therefore, we examine an interpolation method by making use of the advantage of PIV and CFD.
In this paper, two-dimensional cavity flow is also treated as an example of the application. We also devise how to make the velocity vector diagram using the pressure information at the location where the velocity vector is absence.

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Velocity vector distributions of non-Newtonian fluid flow in a channel obstructed by an antisymmetric array of cylinders are measured by means of PTV. The flow pattern of polyacrylamide (PAM) solution differs significantly from that of water. In the case of PAM solution, fluid cannot proceed easily through a narrower passage, which shows that an elongational viscosity of PAM solution is large. On the other hand, in this experiment there is little difference between the flow pattern of water and that of surfactant solution.

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Flows inside a water drop sinking in oil are measured combining new visualization techniques and a PTV technique. The flows have been interested in the relation to the heat and mass transfer phenomena across an interface between two fluids. This study aimed to measure the flow conditions, velocity distributions, in the interface region of a drop, and to correlate the fluid resistances to the quantitative flow conditions.
In order to apply the PTV to the flow measurements, some problems associated with the visualization of the inside area of a water drop have to be resolved. The authors have developed new visualization techniques, which are able to correct the image distortion caused by a spherical surface of a water drop, and able to obtain distinct outline of the drop. It is confirmed that the measured velocity distributions exhibit good correlations to the changes in the drag coefficients of the drops.

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The velocities of both the continuos phase and the dispersed phase of the liquid-solid two-phase flow are measured simultaneously by PIV and PTV techniques, respectively. The fluorescent particles are used as the tracer particles for the fluid phase. A simultaneous image recording system is designed and the images of the tracer particles and the test particles are separated by the optical filters. The ensemble-averaged velocity and turbulent velocity fluctuation of both phases are analyzed and compared with the single-phase flow. The modification of the turbulence intensity of the fluid phase and the preferential concentration of the particles by turbulence are observed by the experiments.

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Development of a high suction performance pump inducer is required for a reusable rocket engine to reduce total weight of a launch vehicle and to increase its reliability. But, flow patterns or pressure distributions in an inducer are not well known. Therefore, observations of flow patterns around an inducer by PIV (Particle Imaging Velocimetry) method were planned for the foundation data for a high suction performance inducer design. In this study, structures of the backflow and the reversed flow are minutely described and discussed.

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A combustor for gas turbine is required to reduce pollutant gas emission. In order to satisfy this requirement, it is needed that combustion process in the combustor is controlled accurately. So, it is important to get an information of interaction between turbulence and combustion. This report deals with aerodynamic phenomena in a swirl type combustor that has two swirlers. Stereoscopic PIV has been used to measure 3-component velocity field of swirling flow without combustion. It was shown that in the swirling flows the interaction of rotational direction is stronger than axial direction. So, two rotating flows are combined and become one rotating flow more quickly. But the distribution of axial direction flow speed is kept to farther downstream as it is.

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The flow patterns in the mock-up model of the cross-flow type mercury target were measured using the PIV technique under water flow conditions at room temperature. The experimental results were compared with the analytical results conducted with the thermal hydraulic analysis code, STAR-CD. As a result, it was confirmed experimentally that the cross-flow could be realized in most of the proton beam path area, where the removal of the high density heat is important, with the proper flow rate distribution along the proton beam path. The analytical result showed the good correspondence to the experimental result. Then the mercury flow field and the temperature distribution were analyzed taking the volumetric heat generation by the spallation reaction into consideration. The volumetric heat generation calculated for the proton beam energy and power of 1.5GeV and 5MW were assumed in the analysis.The mercury flow analysis showed that the maximum mercury temperature less than the design criteria of 300 deg C can be attained with the inlet mercury velocity of more than 1.1m/s and that the recirculation flow seen in the rear of the proton beam path is considered to cause no excessive temperature rise.

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