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阿部 真憲, 李鹿 輝, 中野 政身
2005 年 25 巻 Supplement2 号 p.
161-162
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The study of the formation and migration of sand dunes has a long history, but a sound understanding of the turbulent mechanisms behind dune has proved elusive. In this paper, in order to reveal the detailed vortical structures of different dunes, PIV measurements were performed in a circulating water channel at a constant Reynolds number of 2809. Instantaneous and time-averaged velocity distribution in the side and top planes were obtained and the complex reverse flows and eddies behind different dunes were examined.
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多数のデューンの影響
柳田 幸司, 李鹿 輝
2005 年 25 巻 Supplement2 号 p.
163-164
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In order to reduce power consumption, pipe wear and conveying velocity, a pneumatic conveying system that several dunes are installed in pipeline is proposed in this paper. An experimental study focuses on the effect of installed several dunes in the horizontal pneumatic conveying system in terms of the overall pressure drop and particle flow patterns. It is found that in the lower air velocity range, the pressure drop of the pneumatic conveying with installed several dunes was lower than that of the conventional pneumatic conveying system.
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中島 正弘, 李鹿 輝, 田畑 隆英
2005 年 25 巻 Supplement2 号 p.
165-166
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
As a part of the study on the control of the jet diffusion, the jet flow issuing from the circular pipe with the pliable fluttering fins has been investigated. It is hopeful that these fluttering fins supply the disturbance to the jet flow and the jet diffuses largely under the influence of these fins. In order to investigate the attaching effects of these fins on the jet diffusion, the flow visualization by the LIF method and the image processing by the PIV method have been conducted, by changing the length of the fins. Moreover, the wavelet multi-resolution analysis has been also carried out by using the original images obtained from the LIF method. As a result, it has been clarified that the structure of the jet varies with the length of the fins considerably.
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中野 朋則, 青山 暁, 藤澤 延行
2005 年 25 巻 Supplement2 号 p.
167-168
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The shear-stress measurement by liquid-crystal visualization was extended to the flow along curved surfaces for application to the airfoil study in wind tunnel. The measurement system consists of stereoscopic observation system with two color CCD cameras and stroboscope, which are rotational about the axis of the airfoil. It was found that the magnitude of the shear stress changes along the airfoil surface, which is consistent with the visual observation of separation and reattachment point.
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禿 顕久, 石原 勲, 松本 亮介
2005 年 25 巻 Supplement2 号 p.
169-170
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
As the heat transfer in the thermosyphon depends on natural convection flow inside, it is important to reveal the flow characteristics. Upward and downward flows meet each other in the intermediate section of thermosyphon and then a complicated flow would take place. Under certain condition, mutual interaction between both flows results in multi-branched flow. Present study focuses on such flow regime. Flow field in a series of vertical planes was measured by means of PIV technique. Experiments were conducted by using thermosyphon models; 100mm length, 34 or 46mm diameters. Three kinds of silicon oil with different viscosity were used as the working fluid and temperature difference between cooled and heated surfaces was changed up to 12K. The number of branches increased when increasing in the modified Rayleigh number Ra
* and at maximum 7 pairs of branches appeared for Ra
* =2.9×10
6
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伊藤 貴広, 亀岡 利行
2005 年 25 巻 Supplement2 号 p.
171-174
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Recently, an electronic device is miniaturizing. simultaneously the object of temperature measurement became smaller, and more complex. The measurement of a minute area is difficult of the conventional temperature measuring method. It is already known that the temperature measuring method by thermo sensitive liquid crystal is effective in measurement of a thermal field. But a small field can not measure by conventional method. In this study the temperature measurement is enable by taking a picture of a smaller area by thermo sensitive liquid crystal. The object is temperature distribution of the natural convection. The temperature measurement is enable in a small area.
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文沢 元雄, 福壽 栄一, 後藤 文宏
2005 年 25 巻 Supplement2 号 p.
175-176
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
It is very important to measure the fuel surface temperature without contact. Therefore the measurement system is developed by spot thermometer and DVD camera. The video photographing technique is also developed in high nuclear radiation field. The first step of the experimental method is to take the light from the high temperature media surface using the spot thermometer TR-630 as well as the DVD camera DZ-MV380.
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巨 東英, 齋藤 大道, 鈴木 貴博
2005 年 25 巻 Supplement2 号 p.
177-180
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In the quenching process, heat transfer behavior will is very complex due to boiling, generation of the bubble by the boiling in the quenchant, flaking off of steam film in metal surface. In this research, the behavior of steam film in quenching process was investigated with high-speed video camera by visualization method. The behaviors of the boiling bubbles including generation and movement as well as the breaking during stirring quenching process were clarified. The flow velocity fields around the quenching parts at no stirring and stirring quenching were investigated. In order to identified the heat transfer coefficients by using of the measured cooling curves of surface temperature. Effects of stirring on breaking the steam film were confirmed.
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山本 義洋, 高木 通俊
2005 年 25 巻 Supplement2 号 p.
181-182
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The motorcycle is the vehicle which is not stable in right and left directions, because it runs with two wheels. In addition, the rider of the motorcycle sits astride directly and is not fixed on the seat. On the other hand, the influence of aerodynamics on a motorcycle is big as same as on a car. Therefore, the elucidation of aerodynamic characteristics of the running motorcycle is important when its safety is considered. In this study, the aerodynamic characteristics of 1/5-motorcycle models were measured in parallel-running states inside a low speed wind tunnel. The total pressure distributions in the wakes were also measured and visualized. As a result, the aerodynamic characteristics of the parallel-running motorcycles are strongly affected by the relative positions of the motorcycles and the sign of the yaw moment is changed in the passing-by maneuver, which can be dangerous to the driving.
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林田 隆幸, 酒向 達也, 井上 浩史, 本宮 嘉弘, 福山 邦男
2005 年 25 巻 Supplement2 号 p.
183-186
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In this study, the authors investigated the effectiveness of using a computer simulation for a traffic accident. The accident being simulated was a highway head-on collision caused by a tire blowout on a truck. The accident was investigated in great detail through observing the behavior of the vehicles by reconstructing the accident using various data collected, of which included skid marks left on the road and damage of the vehicles from the computer founded data. Furthermore, the circumstances of the accident were reconstructed in animation to included view of those persons involved (drivers, eye witness) and the efficacy of the accident was examined through the computer simulation.
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本宮 嘉弘
2005 年 25 巻 Supplement2 号 p.
187-188
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Computer simulation for traffic accident is a very useful device to visualize traffic accidents. In this paper, I will show you several simulations of real cases such as insurance fraud, multiple collisions and etc. It can be used to estimate the cause of death of the occupants too.
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小熊 信慶, 飯田 明由, 小久保 あゆみ
2005 年 25 巻 Supplement2 号 p.
189-192
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In order to reduce aerodynamic noise from rearview mirrors, flow visualization and noise measurements were conducted in a low-noise wind tunnel. The tonal noises from rearview mirrors are generated by sinusoidal velocity fluctuations with small steps and gaps on the surface of the rearview mirror. In order to control the sinusoidal velocity fluctuation, a rotational ellipses cylinder was installed at the small step on the surface of the rearview mirror. The tonal noise from rearview mirror with active control device was 15dB smaller than that of the conventional one. The small spots were observed on the surface flow of the rearview mirror with ellipses cylinder. The result showed that the rotational cylinder destroyed coherent vortices and reduced the tonal noise. It reveals that the source of the tonal noise is the sinusoidal velocity on the surface of the rearview mirrors and its control is useful for reduction of tonal noise from rearview mirrors.
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小熊 靖之, 中野 朋則, 藤澤 延行
2005 年 25 巻 Supplement2 号 p.
193-194
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The flow and pressure field on a rotationally oscillating circular cylinder in a uniform flow are studied by PIV measurement in combination with the analysis with pressure Poisson equation. In order to obtain a high accuracy in PIV near the solid boundary, the image deformation analysis is introduced into the PIV analysis. The present result indicates that both the velocity and the pressure field show the periodic variations in the wake, which is synchronized with the rotational oscillation of the circular cylinder.
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田中 洋介, 大津 一晃, 川口 寿裕, 辻 裕
2005 年 25 巻 Supplement2 号 p.
195-196
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In this research, we carried out the evaluation of the measurement accuracy for an in-line stereoscopi PIV system with a single camera. Conventional stereoscopic PIV systems use two or more cameras, thus a complex adjustment of camera settings is necessary. We developed a simple stereoscopic PIV systel composed of a single camera, mirrors and a half-mirror. This system is applied to in-line stereogrammeti method, which requires that the two cameras have the same optical axis. In this developed system, howeve one camera is replaced with the mirrors, and a double particle image is separated using the half-mirror.
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粒子パターン変形が及ぼす影響について
西尾 茂, 桐本 兼輔
2005 年 25 巻 Supplement2 号 p.
197-200
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The mechanism of error vector appearance in PIV image analysis was evaluated by means of VSJ Standard Image, which enables us to obtain error vectors directly. In the present study, the relationship between the deformation and rotation parameters of particle image and error vector appearance was considered through the statistical analysis. Analyzed results shows that the sensitivity parameters for shear flow and rotation were different, and the direct cross corre-lation procedure gives different error appearance characteristics from sub-pixel analysis. Deformation of particle pattern affects the correlation map producing smaller undulation and non-symmetry distribution around correlation peak, and it would be a candidate of major error factor in PIV image procedure.
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山本 恭史, 城 憲一郎, 米原 紀吉, 植村 知正
2005 年 25 巻 Supplement2 号 p.
201-202
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In this paper, we proposed a digital inline holography technique combined with stereoscopic recording for micro 3D-PTV. With the assistance of one mirror, stereoscopic recording is achieved by one single camera, keeping simplicity of optical alignment. Holograms were magnified through a zoom lens. It was confirmed that the uncertainty in the optical-axis direction can be reduced to a few pixel by the proposed technique.
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二宮 尚, 渡辺 淳史
2005 年 25 巻 Supplement2 号 p.
203-204
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Presently, a new measurement algorithm for PIV is proposed that enables us to obtain the three-dimensional velocity vectors at three-dimensional measuring points, i.e., 3-D 3-C PIV. According to the recent progress in PIV, the three-dimensional velocity vectors in a two-dimensional plane, i.e., 2-D 3-C PIV, are easily obtained and have revealed the many features in many kinds of applications. With the use of the cameras under the Scheimpflug condition, clear focus can be obtained for both cameras at different viewing angles and this stereoscopic arrangement enables the 2-D 3-C PIV. In order to obtain the third velocity component, three-dimensional camera calibration is necessary. This means that the three-dimensional position of a particle can also be calculated without implementing any additional devices to 2-D 3-C PIV. Presently, the 3-D 3-C PIV algorithm has been proposed and an actual 3-D 3-C measurement is carried out for a two-dimensional jet.
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混相流への適用を目指して
植村 知正, 山本 恭史, 西尾 茂, 村田 滋, 上杉 健太朗
2005 年 25 巻 Supplement2 号 p.
205-208
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In order to measure three dimensional multiphase flows in a micro scale space, the stereo micro PIV method using synchrotron radiation X-ray is expected to be developed. Selection of tracer particles, and imaging method are discussed in this paper. A stereo matching technique for parallel projected stereo pictures is also examined.
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速水 洋
2005 年 25 巻 Supplement2 号 p.
209-210
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Particle image velocimetry (PIV) can capture velocity vector fields with high spatial resolution. A dynamic PIV system with 2 kHz at mega-pixel frame up to 10 kHz at 512x256 pixels was developed by combining a high-speed camera, a high-speed pulse laser with double pulse option, and a pulse controller. The system has been successfully applied to various types of jet flow, a channel flow, and so on.
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弁デザイン形状の違いが流れ場に与える影響
福田 孝将, 齋藤 淳, 森 一将, 阿久津 敏乃介
2005 年 25 巻 Supplement2 号 p.
211-212
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Three bi-leaflet prostheses (St. Jude Medical, Jyros and On-X valve), were tested in the mitral position under the pulsatile-flow condition. The Dynamic PIV system was employed to analyze the flow field affected by the leaflet shapes and valve designs. The Dynamic PIV system allows to acquire 1000 time-varying velocity fields at 1kHz by using Nd:YLF laser, which is synchronized with a high resolution camera (1024×1024 pixel). 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 small difference in leaflet configuration in the bi-leaflet prostheses generates noticeable differences on the flow.
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桑原 譲二, 岡本 孝司
2005 年 25 巻 Supplement2 号 p.
213-214
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Shell and tube heat exchanger are widely used for various devices, such as steam generator, evaporator, and so on. It is very important to understand the flow structure around the tube and the relationship between the flow and the tube vibrations.
In this study, the cross-flow in the tube bundles were measured using the Dynamic PIV. The fluctuations of the flow structure are clearly obtained with high spatial and high temporal resolution. The characteristics of the vibration mode of the tube will be discussed with the fluctuation data.
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治田 真一, 中村 瑞木, 冨川 昌義, 飯田 明由
2005 年 25 巻 Supplement2 号 p.
215-218
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The purpose of this research is to clarify generation mechanism of aerodynamic force of flapping airfoils 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, a flapping machine was developed by using real insect's wings and link and motor mechanism. Flow field around the flapping machine was visualized by using smoke-wire method and dynamic PIV. Experimental results showed the down flow shed from the airfoils impinged to the airfoil, which reduced aerodynamic force of down stroke process. On the other hand, upper flow was generated in up stroke process, which made lifting force of flapping airfoil near the top dead center.
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渡辺 佳恵, 橋爪 勇嗣, 藤澤 延行
2005 年 25 巻 Supplement2 号 p.
219-220
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In order to understand the turbulent structure of the buoyant plume, the simultaneous flow visualization and the velocity measurements by PIV are carried out in vertical and horizontal planes of the plumes. The flow visualization result shows the periodic formation of mushroom type vortices in the plume, which is induced by the ejection of the hot fluid from the nozzle exit by the influence of buoyancy. It is found from the PIV measurement that the ejection velocity reaches more than 3 times of the plume velocity at the nozzle exit and entrains the cold fluid into the plume, which contributes the large growth rate of the plume development.
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梅田 眞三郎, 若林 友則, 万本 信三, 堀井 清之
2005 年 25 巻 Supplement2 号 p.
221-224
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Researches for stabilizing a plain liquid film are not still sufficient for industrial applications. The improvement of film-forming technology through thin-film jet flow for the purpose of maintaining freshness in food products and protecting operational environments of electronics systems is crucial in these industries. A new nozzle using a composite flow network has been developed for plain air film stabilization without film break. The design consists of a slit duct with layers of diamond-shaped cylinder bundles. An experimental study was performed to investigate flow characteristics of efflux in composite flow networks by means of PIV. It is disclosed that it is conceivable to extend longitudinal vortex flow in composite flow networks through interacting with flip-flop flow exiting from a pre-fixed multiple-intersecting flow network in order to strengthen and thus stretch its efflux.
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橋爪 勇嗣, 渡辺 将生, 藤沢 延行
2005 年 25 巻 Supplement2 号 p.
225-226
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
As a purpose to know the mechanism of energy transportation in turbulent Rayleigh Benard convection, the measurement experiment of temperature and velocity at turbulent thermal convection field is carried out by the liquid crystal thermometry and velocimetry. From these experimental results, the distribution of mean and fluctuation of temperature and velocity, Reynolds stress, turbulent head flux and dissipation are obtained. These values indicate a balanced distribution of turbulence energy at spacious field without neighboring wall boundary.
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渡辺 将生, 橋爪 勇嗣, 藤沢 延行, 船谷 俊平
2005 年 25 巻 Supplement2 号 p.
227-228
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In order to understand the development of the plume in turbulent thermal convection, the temporal and spatial variations of temperature and velocity in the horizontal fluid layer are measured by the scanning liquid crystal thermometry and stereo-velocimetry. It is found that the growth of the plume is mainly associated with the temperature field near the heated boundary, while it is greatly influenced by the three-dimensional velocity field induced by the buoyancy.
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笹沢 哲也, 平原 裕行, 川橋 正昭, ホセイン ジャキル, 野々村 義民
2005 年 25 巻 Supplement2 号 p.
229-232
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
This paper describes a study of integrated small wind turbines for built environment. In order to create the amenity space, the prediction of the wind flow is important to evaluate the windbreak deficit effect and turbulence in the wake. In the work, flow field around a building, on which a integrated wind turbines system installed are investigated by using model wind turbine. Result indicates the remarkable effect of the integrated system on the flow regime in the wake. In addition, the distance between the turbines is most influenced on the blocking of the wind and the inclination angle between the shear layer and array is secondary important factor.
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N Erkan, M Ishikawa, K Okamoto
2005 年 25 巻 Supplement2 号 p.
233-234
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Dynamic PIV (Particle Imaging Velocimetry) measurement technique was applied to the high-speed mist flow in a narrow channel with an obstacle. The boundary layer was visualized with a high-speed camera and a high repetition double-pulse laser. The square flow channel has the dimensions of 10×10 mm and an oil and nitrogen gas mixture flows through it with Reynolds numbers of 11, 000 and 34, 000 respectively (kinematic viscosity fluid is taken to be as μ=le-5m
2/s). Although, the Reynolds number of 34, 000 was hard to capture enough number of images, which shows vortex evolution in time, for the time resolved analysis of boundary layer, the vortex evolution at the edge of thin plate. has been clearly visualized in temporal domain. Velocity fluctuation transfers velocities in the boundary layer were calculated by two-point velocity cross-correlation. Fluctuation transfer velocities were in good agreement with the some measured vortex transfer velocities..
1) Report for Int. Workshop on Dynamic PIV 2004 Tokyo.
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城 憲一郎, 植村 知正
2005 年 25 巻 Supplement2 号 p.
235-238
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
For stereo measurement, diffraction grating is used for laser light division into two rays. Direction of divided rays depends on only wavelength of light and the interval of grid lines. The advantage of stereo measurement using this idea is that an optical adjustment is extremely easy because the stereo arrangement angle is fixed. This paper describes effects of optical performance and position of diffraction grating on quality of stereo image and accuracy of measurement.
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山田 浩平, 伊藤 光
2005 年 25 巻 Supplement2 号 p.
239-242
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Goertler vortices generate in laminar boundary layers on concave walls. The horseshoe vortices generate downstream, and these are broken in laminar-turbulent boundary layers. The experiments were carried out with a concave wall of Im in radius of curvature for 3m/s of main airflow velocity. The behavior of the horseshoe vortices was visualized by smoke and measured with a hot-wire. Additionally, the visualizations and the velocity measurements at four positions were conducted simultaneously. In this paper, the process of the horseshoe vortices breakdown is described.
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異なる形状の凹曲面前縁板の場合
十文字 航洋, 伊藤 光
2005 年 25 巻 Supplement2 号 p.
243-246
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Gortler vortices were developed in boundary layers on concave walls, and the high-frequency horseshoe-vortices were generated in the upwash region between pairs of Gortler, vortices downstream. In this experiment, flow visualization by smoke and Hot-wire measurements were conducted for the free air stream velocity of 2.5 m/s using a concave wall of 1 m radius of curvature with different shapes of leading edge plates. The relation between the forced wavelength given by the plate and secondary instability flows of horseshoe vortices mode and sinuous mode are also discussed.
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上杉 知弘, 川橋 正昭, 平原 裕行, 座間 淑夫
2005 年 25 巻 Supplement2 号 p.
247-250
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In general, spray field is a complicated and three-dimensional two-phase flow. The structure of it indicates strong correlation between size and velocity of droplets. Thus simultaneous measurement of size and velocity of the individual droplet in the spray is needed. In the recent years, the techniques based on Interferometric laser imaging for droplet sizing (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 field of droplets is based on the characteristic of light scattered from droplets. In this technique, droplet size was estimated by number of interference fringes, and 3D velocity field was reconstructed with 3D-PTV. Moreover, holography technique has been applied in order to separate the overlapping interferometric image, and its feasibility was verified.
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鈴木 和也, 長谷川 富市, 鳴海 敬倫
2005 年 25 巻 Supplement2 号 p.
251-252
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The flow behavior known well of the fluid in ordinary scales is not necessarily similar in a minute scale. Therefore, it is necessary to examine the flow passing through a minute area in detail for so called Newtonian fluids as well as for complex fluids. This paper presents the result of optical experiments offlows through a slit. Ion Exchange Water, Silicone Oil and Liquid Paraffin were used as test fluids, and made to flow through a two-dimensional slit by using a pump of syringe type. We used Mach -Zehnder interferometer, and took a picture of the changes in the brightness and in the interference fringes with the digital video camera.
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橋本 隆彦, 藤沢 延行
2005 年 25 巻 Supplement2 号 p.
253-254
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In this paper, the mechanism of separation control of flow around airfoil by internal acoustic excitation near the leading edge of an airfoil was studied by flow measurement by PIV. The experiments are carried out at various combinations of non-dimensional frequencies and the momentum coefficients, while the Reynolds number is fixed to 1×10 4. The mean and fluctuating properties of the flow around the airfoil indicate that the separation region on the suction surface of the airfoil is reduced at a certain combinations of non-dimensional frequency and momentum coefficient of the acoustic excitation control. It is found that the synchronized vortex structure, which is well correlated with the acoustic excitation, prevails on the suction surface of the airfoil at the optimum condition and controls the separation phenomenon.
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山本 富士夫, 村井 祐一
2005 年 25 巻 Supplement2 号 p.
255-256
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The analytical algorithm of PIV and PTV has advanced in the last two decades from simple cross correlation method to binary image cross correlation method, Delaunay tessellation method, velocity, gradient tensor method, and recursive cross correlation method. In parallel, useful post-processing schemes for PIV/PTV such as ellipsoidal equation method and inverse analysis method were proposed so that detailed flow structure could be evaluated including pressure field. This paper concerns with such a history of the research and future possibility for further advance of the PIV/PTV.
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市川 直樹, チャン ピーター
2005 年 25 巻 Supplement2 号 p.
257-258
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
With the wide development of microfluidic applications, the importance of the flow field analysis in a is growing. Because of complicated 3-dimensional (3-D) structures for microfluidic systems and 3-D flow structures near gas-liquid interface, the necessity of measurements for 3-D flow field measurement is now increasing. In this paper, we are developing a 3-dimensional PTV (Particle Tracking Velocimetry) system for observing flow in a 100 μm x 55 μm microchannel. There are several crucial points to develop a micro-3D-PTV system, such as the requirement for lens, darkness of images and calibration method. Using two lenses of long working distance and focusing length and high-speed cameras, we successfully obtained 2 different anglular images with 200 frame/s. A microchannel was fablicated from PDMS, and distilled water/ethanol with 5μm diameter fluorescent particles was used as the test liquid. Marangoni flow near the gas-liquid interface was successfully observed stereoscopically, although the obtained images were not so clear.
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水本 飛鳥, 末包 哲也, 津島 将司, 平井 秀一郎
2005 年 25 巻 Supplement2 号 p.
259-260
発行日: 2005/10/01
公開日: 2009/07/31
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フリー
Though CO
2 leakage from a geological storage site through wells and rifts represents a major concern, it is difficult to monitor the CO
2 leakage. In this paper we have experimentally investigated the proton relaxation time (T1) of carbonate-water filled in a porous media at high pressure with an NMR system to see the dependence of T1 on the concentration of CO
2. From the results, it has been observed that the higher the CO
2 concentration is, the shorter the T1 of the carbonate-water in the porous media becomes. Therefore this information is very useful to apply NMR logging to monitor the CO
2 leakage.
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籔野 真大, 川口 寿裕, 辻 裕
2005 年 25 巻 Supplement2 号 p.
261-262
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
MRI (magnetic resonance imaging) measurement was performed for a horizontally vibrated granular bed of binary mixtures in a liquid. Larger particles tended to rise through the central region. The size ratio of larger to smaller particles affected the segregation phenomena. The experimental results were compared with results of a DEM simulation. The calculated results agreed qualitatively well with the experimental results.
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保田 和則, 小原 教弘, 千葉 訓司, 森 教安
2005 年 25 巻 Supplement2 号 p.
263-266
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Axial velocity distribution of a steady tube flow was measured using magnetic resonance imaging (MRI). Test fluids were aqueous solutions of carboxymethyl cellulose (CMC) containing solid particles (glass flake or glass bead) at high volume fractions. As a result, we observed a plug-like velocity distribution in the tube flow. This velocity distribution measured by MRI had a good agreement with that numerically calculated using the viscosity curve of the test fluid. Furthermore the effect of suspended particles on the velocity distribution in the tube flow with an abrupt contraction was also examined. We observed a plug flow for the CMC solution and the bead suspension, but a concave region in the velocity distribution near the centerline at upstream of the contraction for the concentrated flake suspension. This velocity distribution is caused by the shape of the glass flake particle.
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長谷川 光大, 鳴海 敬倫, 長谷川 富市
2005 年 25 巻 Supplement2 号 p.
267-268
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
We have investigated particle migration phenomena in a torsional flow of bi-dispersed suspensions or a suspension with aggregations. In the case of bi-dispersed systems, a small amount of larger/smaller black particulate suspension was injected into a base white one, and the diffusion or migration of the black particles in the flow was observed. When the two plates were parallel, only the diffusion of the black one was observed. But, when the two plates were a little inclined, larger/smaller particles migrated to the lower/higher shear rate region in many cases. Moreover, we have observed the migration of aggregated particles toward the center.
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佐藤 宣明, 関根 大介, 高橋 勉, 白樫 正高
2005 年 25 巻 Supplement2 号 p.
269-270
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Effect of elasticity on Hele-Shaw flow is investigated using M1 fluid, which has strong elasticity and constant shear viscosity, by applying the photochromic technique for flow visualization. Elongation stress due to fluid elasticity has influence on the flow patterns of M1 similar to the case of PAA-solution with intense shear-thinning.
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石丸 賢策, 辻 知宏, 蝶野 成臣
2005 年 25 巻 Supplement2 号 p.
271-272
発行日: 2005/10/01
公開日: 2009/07/31
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フリー
We performed two kinds of fundamental experiments for developing liquid crystalline micro-actuators. The first experiment was to measure the velocity distribution of back-flow between parallel plates under an electric field. The gap of an experimental cell was 50μm, and its twist angle was 0°. We obtained that the velocity distribution was antisymmetric with respect to the center plane of the cell. In addition, the magnitude of measured velocity was agreed well with numerical predictions. The second experiment was to try to move the upper plate, by the induced back-flow. Gap of the plates was 300μm, and weight of the upper plate was about 0.05g. As a result, the upper plate was moved by 38μm with the maximum velocity of 179μm/s.
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深田 純, 鳴海 敬倫, 渡部 博, 長谷川 富市
2005 年 25 巻 Supplement2 号 p.
273-276
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
We have examined the transient behavior of the liquid crystalline polymer solution in successive simple shear and squeezing flows between two parallel plates. At the first stage, the simple shear flow was applied to the liquid crystalline polymer solution, and then the squeezing flow was started. Moreover, after the squeezing motion, a simple shear flow with different gap was applied again. We had observed the structural change of the liquid crystalline polymer solution in these successive flows with polarizing microscope. Furthermore, the dichroism and orientation angle were measured with a laser optical measurement system. It was found that the structure generated in the first simple shear flow was maintained and slid for a while in the squeezing flow. Moreover, at the commencement of the last shear flow after the squeezing motion where the structure was already destroyed with the squeezing motion, a rapid and large structural change was observed.
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西田 政弘, 田中 皓一, 池田 勇介, 田中 祐輔
2005 年 25 巻 Supplement2 号 p.
277-278
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The impact behavior of aggregated particles subjected to projectile impact at velocities less than 20 m/s is investigated experimentally. The aggregated particles consist of nylon spheres arranged randomly in a rectangular parallelepiped container. A steel sphere strikes obliquely several nylon spheres on the top of aggregated particles. The motion of aggregated particles and steel projectile is recorded by two high-speed video cameras. The effects of the impact velocity and impact angle of steel projectile on the motion of steel projectile and aggregated particles after impact are discussed in detail.
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吉田 太一, 川口 寿裕, 辻 裕
2005 年 25 巻 Supplement2 号 p.
279-280
発行日: 2005/10/01
公開日: 2009/07/31
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フリー
This paper describes the measurement of particle behavior inside a spouted bed by using MRI. We measured the particle velocity distribution in the annulus region in a three-dimensional cylindrical spouted bed. The tagging method and the phase method, which are the velocity measurement technique of MRI, are employed to measure the particle velocity distribution. A stagnation region near the corner of the vessel is clearly visualized by the tagging method. A plug-like motion of particles in the upper part is also visualized. The velocity distribution obtained by the phase method is integrated to calculate particle flow rates at each height.
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伊藤 瑛人, 佐合 康弘, 田中 敏嗣, 辻 拓也
2005 年 25 巻 Supplement2 号 p.
281-282
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
In gas-solid flows, particles form a spatial structure known as "particle cluster". However, mechanism of the particle clustering is still not known well. In this paper, particle cluster's multi-scale structures are examined in details by applying the high/low-pass filters to flow field data obtained from point-force DNS which takes particle-particle collisions into account. Keywords: Particle clustering, Multi-scale structure, Filters, Gas-solid flows, Direct numerical simulation
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佐々木 幹夫, 細越 英憲, 明堂 健
2005 年 25 巻 Supplement2 号 p.
283-284
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
The solid-liquid multi-phase flow is observed with the high speed camera, the rotation behavior characteristic of the solid particle is examined, and the experiment results are shown in this paper. In this experiment, the pipeline was used, and the diameter of the pipe is 5 cm, the specific gravity of the solid particle is 1.06
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尾川 朋史, 角田 勝, 鈴木 節夫, 柿崎 容子
2005 年 25 巻 Supplement2 号 p.
285-286
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
An experimental investigation was made on pulp-suspension flows in a duct with a square cross-section and around a circular cylinder. The flows were visualized by the light transmission method. A method for obtaining the instantaneous, local pulp-fiber concentration was suggested. Effects of the pulp concentration on the flows were examined and the relationships between their flow pattern and Reynolds number were discussed.
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川久保 政洋, 松崎 充男, 木倉 宏成, 有冨 正憲
2005 年 25 巻 Supplement2 号 p.
287-288
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
Dropwise condensation process consist of several discontinuously and irregular process. Therefore, it is difficult for dropwise condensation to analysis of continuously and regular methods as filmwise condensation and another heat transfer phenomenon. It is widely thought that drop growing speed and drop size distribution is paramount importance for construction of dropwise condensation theory. In addition, it is well known that the presence of non-condensable gas is reduced the heat transfer coefficient. However the research of drop growing speed and drop size distribution is not performed a lot. The objective of this study is to measure the departure drop diameter and the drop size distribution in the presence of non-condensable gas, and visualization of dropwise condensation process is performed using a digital video camera. In the result of visualization method, it is understandable that the causes with decreases of heat transfer coefficient and amount of heat transfer in the reduction of drop glowing speed.
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大橋 順一, 稲葉 一昌, 田坂 裕司, 村井 祐一, 武田 靖
2005 年 25 巻 Supplement2 号 p.
289-290
発行日: 2005/10/01
公開日: 2009/07/31
ジャーナル
フリー
An experimental study of air-water two-phase slug flow in a horizontal tube is performed using UVP and high-speed camera. The spatio-temporal velocity profile on the vertical axis is obtained and analyzed using phase-averaging technique. The results show that an upward rising flow is induced inside the liquid slug in the central region of the tube, and remains in the downstream liquid layer below the gas bubble. This implies the liquid slug has a secondary circulation in the cross-section.
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