STA-MCA anastomosis is known as one of the surgeries for the stroke prevention, which intended to perfuse the cerebral artery. However, this surgical remedy has no general criterion. To assess the effect of this operation, Computational Fluid Dynamics (CFD) is performed for two patients. The vascular lumen geometries are extracted from patient's 3D-DSA images. Additionally, different anastomosis conditions, bypass angle or site, are assumed. As a results, there is a little change in mass flow rate between conditions of the different bypass angle. In contrast, mass flow rate of the M2-part bypass increases at more branch arteries than that of the M4-part bypass. This may mean M2 bypass form could be more effective than M4 bypass one.

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Currently, computational fluid dynamics (CFD) is a widely used analysis method in the medical field, and there are many studies investigating carotid lesions. However, outlet boundary conditions strongly affect CFD results. This is particularly remarkable in cases with high ICA stenosis rates. In those cases, there is still no appropriate outlet boundary condition. For this problem, new approaches of setting outlet boundary conditions are proposed for CFD simulations of the human common carotid arteries (CCAs) bifurcation based on the concept of energy loss minimization at flow bifurcation (Zhang et al. 2013). In this study, we investigate whether this approach is appropriate for CFD simulations in CCAs with high ICA stenosis ratios. The CFD results indicated that the tendency of outflow ratios is similar to that of empirical relationship.

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Leukocyte rolling is physiological phenomenon and it is important process to migrate to inflammatory sites after the leukocyte adhere to endothelial cells. It is said that leukocyte rolling closely relates to arteriosclerosis or cancer metastasis. However, the mechanism of leukocyte adhesion to endothelial cells hass not been sufficiently understood. In this study, we mimicked the leukocyte rolling in a microchannel by coating E-selectin on a epoxy-functionalized glass substrate. Uniform coating of E-selectin by FITC-conjugated anti-E-selectin was preliminary confirmed. We measured leukocyte rolling behavior on the substrate. As the result, we succeeded in the observation of the decreased leukocyte velocity by the interaction between leukocyte and adhesion molecules.

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Hemodynamic researches about cerebral aneurysm have been widely performed to estimate or predict the danger of aneurysm growth and rupture in patients. In this study, we developed an automated in vitro measurement system of flow fields in the aneurysm models based on the scanning stereoscopic particle image velocimetry. The method of vessel wall estimation by using the PIV data, which is quite essential to carry out a hemodynamic evaluation, was investigated; extrapolation of velocity-gradient and image superposition were tested. As a result, the accurate estimation about the vessel wall from superimposed images became possible, and it is expected that more accurate hemodynamic evaluation can be achieved to clarify the mechanism of aneurysm growth and rupture in future.

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Circulating tumor cells (CTCs) are tumor cells shed into bloodstream and would be a primary cause of metastasis to the other organ. Thus, CTCs separation and detection have been actively researched. In the present study, we investigated a concept of two-step dielectrophoresis (ts-DEP) with high separation efficiency for isolating CTCs from other similar-sized cells as a further step of the size-based separation. The developed device showed 98.0 % separation of polystyrene beads by different surface modification. We have also demonstrated 89.8 % separation ratio of SP2/O-HEL from lymphocyte. Dielectric characteristics of 10 kinds of human tumor cells were examined. The results implies a possibility of the discrimination of epithelial and non-epithelial tumor cells.

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For the purpose of separating particles in horse blood at the size threshold of 20μm, a simple microfluidic device with the depth of 110μm contracted flow part was developed using a rapid prototyping. It was found that the particles more than 30μm were separated from all over the horse blood by 100%, but the improvement of the micro channel structure is necessary for the separation of the particle of around 20μm. And moreover, the yeast cells with the diameter of 5μm were selected as sample detection particles after the separation. The newly flow cytometry with the wavelength level of 400-650nm was developed to detect the yeast cells. It was found that the excitation fluorescence spectra patterns typically presented in yeast cells.

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Neutrophil is known as one of the immunological system, and it has chemotaxis by concentration gradient of cytokine. In general, the neutrophil is moved to high concentration of cytokine in the blood vessel, and derived to the inflammation areas. However, the mechanism of propulsion has not been elucidated yet. By understanding this mechanism, it can be applied to medical technologies such as drug delivery systems and micro machines. Therefore, it is necessary to elucidate the principle of neutrophil's propulsion. In our previous investigation, it was found that concentration gradient on the surface of neutrophil is reverse toward surrounding fluid. In this paper, concentration on the surface of neutrophil and surrounding fluid are examined computationally by concentration gradient of cytokine. From the computational result, the reverse concentration gradient occurs by increasing diffusivity of cytokine or adsorption/desorption coefficient. It is concluded that the fluidity of neutrophil surface influences neutrophil's motion.

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Glycocalyx layer on endothelial cells (ECs) has filtering function related with the specific mass transfer. To evaluate the mass transfer, time-course measurement of concentration distribution in the glycocalyx layer is one of the effective approaches. However, spatial resolution of conventional methods was not enough to observe the layer. In the present study, in order to clarify the detail mechanism of the mass transfer, we developed a novel investigation method of mass transfer in a glycocalyx layer of an EC using a super resolution LIF. As the result of a demonstration of the method, we discovered that the effective filtering area was about 28 times wider than the glycocalyx layer of 0.43 μm thickness.

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Total internal reflection fluorescence microscopy (TIRFM) is a powerful tool for analyzing 3D fluid flow in microchannel. To visualize the 3D fluid flow via TIRFM, intensity calibration of a fluorescent particle is required by using calibration plates, carrying a set of nano-steps of different heights. In the present study, to discern the micro-structures in water, TIRFM visualization is carried out by a refractive index-matching method using a water employed as a working fluid. The MEXFLON obstacles is chosen to be able to adjust its refractive index to match to that of the water with an index of 1.333. We have demonstrated a fabrication technique for making the micro-structures on a glass substrate by employing thermal nanoimprint. In summary, we have succeeded in the fabrication of micro-structures made of a polymer resin and used it for the visualization of the fluorescence intensity in a water.

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Butterflies fly by skillfully controlling the deformation of the wings, which contain many veins and can undergo elastic deformation. A number of studies on the mechanism of butterfly flight have been carried out. Recently, there have also been many attempts at visualizing the flow field around insect wings. The present authors have investigated the vortex structure and dynamic behavior produced. However, the relationship between the dynamic behaviors of the vortex rings and the dynamic lift has not been understood sufficiently. In the present study, we performed the direct measurement of the dynamic lift generated by a flapping butterfly using six-axes sensor, and investigated the detailed relationship between the dynamic behaviors of the vortex rings and the dynamic lift.

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We recorded the flight path of a swift using a video camera with a three axis digital gyro module and investigated the relationship between the swift tail motion and the change in the flight path. The swift was found to open the tail before a steep climb. In order to analyze this relationship, the flow around a swift was numerically simulated.The simulations showed that the open tail stabilized the wake flow for the attack angle of 10°. In addition, the simulation revealed that the transient tilting motion of the tail induced effectively a temporal increase in lift force before flow separation on the tail.

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To investigate the aerodynamic effects of leading-edge serrations of owl wings, aerodynamic force measurement and Particle Image Velocimetry (PIV) of the 10th primary feather of an Ural owl and artificial feather models were performed in a wind tunnel. The mean chord length of the owl feather was 28.6 mm and that of the models was 30 mm. The lengths of the artificial serrations were 0, 3, 6 mm and the spacing was 1 mm. The wind velocity was 3 and 5 m/s. The force measurements show that both the owl feather and the artificial models with serrations have a moderately increasing in lift coefficient compared with that of the model without serrations. The PIV results demonstrate that the serrations suppress velocity fluctuations in separated flow. Our results indicate that the leading-edge serrations are likely capable to enhance the robustness of the force generation at larger angles of attack.

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We have studied experimentally about the flow on a ciliary respiratory epithelium with the relation between a viscosity of mucus and a generated flow velocity using μPTV measurement. We used a fresh dissected mouse respiratory epithelium for our experiment, and observed a flow on it by using a confocal microscopy for tracing micro fluorescent particles, which dispersed in the mucus on the ciliary cells. The frequency of ciliary motions and velocity of mucus were measured in several cases with different viscosity of mucus. The driven force for generating ciliary flow has a non-linearity with an increasing of viscosity. Our findings would play a medical role to clarify a mechanism of mucus flow on a ciliary respiratory epithelium with its viscous changing.

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The objective of this study is to understand the formation of school movement with the organism. Two factors relate the formation of school. One is the character of living things. The other is the stimulation from the environment. We numerically investigated the formation of school to change by influence of the character of living things and the stimulation from the environment. As a result we understand the relationship between the coefficient of restitution and formation of school movement.

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The objective of this study is to observe the escape response of flies. Their turning speed is very fast. We developed a system to observe the fast movement. The details of development is used two galvano mirror and high speed camera in this system. The moving speed of the object it is possible to observe up to 250mm/s. The details of development of two galvano mirror and high speed camera in this paper. It shows the state of movement of the flies captured using a system developed and the developed system.

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The vortex method is analysis method which discretely represents vorticity of the flow field as a large number of micro-vortex particles. This method has good stability in the numerical integration and does not need the computational grid in the flow field. Using this method, the velocity field is obtained from the calculated vorticity field using the Biot-Savart formula and potential of upwelling. The pressure field has been calculated by using the unsteady Bernoulli equation. The purpose of this study is to analyze the flow around the shark and calculate the forces acting on the shark in three-dimension. Our results indicate that driving force has a large influence of the vortex.

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Ski jumping is a sport which competes the flight distance and the flight form, and jumpers attempt to fly as far as possible. In the regulations for ski jumping competition, the outstretched fabric must show a medium air permeability of a minimum of 40 liters per m2/sec under 10 mm of water pressure. However, the effect of the air permeability of ski jumping suits on aerodynamic characteristics has not been completely clarified yet. The purpose of this study is to investigate the effect of air permeability of jumpsuit fabrics on aerodynamic characteristics, and three types of fabric with different air permeability are examined from aerodynamic point of view. The wind tunnel experiments were carried out using the fabric clothed elliptic cylinder. The aerodynamic forces and velocity distribution were measured for four fabrics with different air permeability.

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The present aim is to reveal the flow past a rotating pipe which is immersed parallel to the mainstream. At first, we conduct field observations of a flying pipe in rotation using a pair of high-speed video cameras, together with motion analyses based on their recorded images, which quantitatively show paths and the change of kinetic parameter such as rotation parameter Ω^* of the flying pipe. Here, Ω^* represents the ratio of pipe's rotating velocity at the outer diameter to flow velocity of the mainstream. As a result, Ω^* monotonically increases with increasing travel distance X. In addition, we conduct numerical simulations by a finite difference method based on the MAC scheme, whose results suggest that the pipe-rotation effect becomes remarkable for a rotation parameter Ω^* > 0.4. This suggests that the flight at Ω^* ≈ 0.4 is suitable. Besides, at Ω^* ≥ 1.8, the axisymmetry of wake becomes broken.

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A badminton shuttlecock generates significant aerodynamic drag and has a complex flight trajectory in actual flight. In the present study, aerodynamic forces were measured at high angles of attack. The objective of this study was to investigate the aerodynamic stability of a badminton shuttlecock. A shuttlecock is aerodynamically stable for the pitch movement just after impact. It was confirmed that the aerodynamic stability of a badminton shuttlecock is related to behavior of vortices separated from the shuttlecock skirt.

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The aerodynamic properties of an archery arrow are investigated experimentally and numerically. The boundary layer along A/C/E shaft (Easton) remains laminar in the Reynolds number range Re < 1.3 _ 10^4, while it becomes turbulent for Re > 1.8 × 10^4. In the transition range 1.3 × 10^4 < Re < 1:8 × 10^4, two values of drag coefficient CD are measured, i.e., about 1.5 (laminar) and about 2.6 (turbulent). We compute the trajectory and attitude of an arrow in free flight numerically, and the time evolution of the angle of attack is determined, whose influence on the boundary layer transition is discussed.

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The decrease in fluid resistance is one of the important keys for the purpose of shortening of the sports time record. The development of low resistance cloth as the application to sports is very important. This study is intended to suggest the best piece of cloth in specific speed area of sports. The fluid resistance concerning the change of cloth materials, surface roughness, surface processing method, seam position and the difference in sewing were investigated by one of the authors. In this time, Influence of slack of the clothes was also investigated. In addition, we performed the aerodynamics experiment of the sports wears which considered the seam position of the cloth as a result of cylinder model and obtained an interesting result. The obtained results showed that there were no influence on the seam position and cloth materials.

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Recently we have enjoyed the sport "Ultimate" using flying disk in the world. Ultimate game is composed of seven people per team. The flying disk used in this competition isn't made in Japan. So, it is expected to develop the inexpensive and highly efficient flying disk of Ultimate. In this research, we understood the aerodynamic properties of flying disk by fluid forces measurement and Stereo-PIV measurement, CFD analysis. We verified the appropriateness of CFD analysis by comparing fluid coefficients of experiment with that of CFD analysis.

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In order to obtain the exact universal Karman constant in an equation of a mean velocity profile based on log law, the friction factor for a fully developed pipe flow is examined in high Reynolds number up to Re_D=1.8×10^7 and with high accuracy using the High Reynolds number actual flow facility "Hi-Reff". Using inner scale variables estimated by the present friction factor, the velocity profile measured by LDV in the same measurement configuration for the friction factor is normalized in order to observe the consistency of the Karman constants between both the measurements. The Karman constant is estimated to be 0.385 by the friction factor which is almost consist with the result by the velocity profile for Re_D>3.0×10^5.

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LDV (Laser Doppler Velocimetry) measurement has been made in the high Reynolds number (1010≦Re_τ≦20700) turbulent pipe flow to clarify its velocity properties. The accuracy of the mean velocity in LDV measurement was checked by a comparison between the integration of the mean velocity profile and the actual flow rate measured by a weighting system in AIST (Advanced Industrial Science and Technology), NMIJ (National Metrology Institute of Japan). Mean velocity overlap region satisfies power law and log law, each coefficients are γ = 0.145, C = 8.41, κ = 0.383 and B = 4.38, respectively. Log-linear region in the turbulence intensity profile is observed at Re_τ = 20700, where coefficients are A_1 = 1.44, B_1 = 1.65. This log relation almost collapses mean velocity log region.

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Detailed experiments have been made for effect of the adverse and favorable pressure gradients on the low of the wall in turbulent boundary layers. The local wall shear stress was measured by a direct measurement device. Mean and turbulent velocity profiles were measured by hot wire anemometer. A new velocity scale defined by considering significant contribution of inertia term in integrating the equations of motion was applied to the near wall statistical properties. The log-law modified with the new velocity scale agrees well with experimental data. The streamwise turbulent intensity profile in the wall layer is likely to be scaled successfully with the new velocity scale.

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We try to obtain the description on the logarithmic velocity profile in the terms of the numerical exact solutions. Here the plane Couette turbulence with the eddy viscous model is considered. We study bifurcation structure arising from Gentle UPO (Unstable Periodic Orbit) reported by Kawahara and Kida(1) in Navier-Stokes equations. We find that the UPOs in Navier-Stokes system connect to those of LES system and the Gentle UPO is a simple edge state of LES turbulence.

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Direct numerical simulations (DNSs) are used to analyze a flat-plate turbulent boundary layer with separation and reattachment. In the present DNSs, the strong blowing and suction are imposed at the upper boundary for producing a large turbulent separation bubble, thus dealing with massive separation. Particular attention is given to the Reynolds stress budgets and the similarity to those in a backward facing step.

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Simple evaluation method of fluid resistance on the hull with roughness is demanded in optimum ship management. In this study we replaced the three dimensional irregular roughness by the "set of multi-dispersed cone model" (SMCM) characterized by the pdf of peak heights 3fpeak. Bayes estimation of 3fpeak from the simple inline measurement of roughness curve has made. We also proposed the pressure drag of three dimensional roughness based on the SCM model. The applicability and limitation were discussed based on the comparison of model estimation and measurements.

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We carried out direct numerical simulation for turbulent flow and heat transfer in a channel with gentle two-dimensional wavy surfaces, and investigated the possibility of drag reduction and heat transfer enhancement. The slip velocity was assumed to be proportional to the velocity at an adjacent grid point to the wall. Three proportional constants are used. The computational results show that the mean wall-shear stresses for the wavy walls do not depend on the slip velocity, and are lower than those for a non-slip flat wall. The mean Nusselt number for the wavy walls increases with an increase in the slip velocity. This increase in the Nusselt number is due to the decrease in the mean temperature gradient in the buffer region, which is due to the gradient of turbulent heat flux.

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The relationships between characteristic vortical structures and the wall surface pressure fluctuations in a rough wall turbulent boundary layer with zero pressure gradient are investigated by means of laboratory experiments using a wind tunnel and velocity, shear stress, and wall pressure measurements. To investigate the relationships mentioned above, simultaneous measurements of the streamwise flow velocity near the wall, the wall shear stress fluctuations, and the wall pressure fluctuations were carried out using an I-type hot-wire probe, a near-wall hot-wire probe and a microphone pressure sensor. Characteristic vortical structures are presented by the wall typical pressure fluctuations time history distributions obtained by using conditional sampling methods of the wall-shear stress maximum value and its interval.

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Approaching process of the turbulent pipe flow subjected by sudden change of the wall roughness has been investigated experimentally. The mean velocity, streamwise turbulent intensity, Reynolds stress profiles and the local wall shear stress were measured for the initial stage of the process after change wall condition from rough to smooth. The mean velocity profiles show acceleration before approaching to fully-developed smooth wall flow; overshoot behavior can be seen for the relaxation process. The local wall shear stress takes larger value for the acceleration of the near wall mean velocity profile and corresponds to larger Reynolds shear stress near the wall.

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To investigate the modulation of turbulence structures such as velocity streaks and quasi-streamwise vortices in turbulent boundary layers on various rough walls, direct numerical simulations were carried out by solving the fundamental equations of compressible flow with the external forces which modeled the effect of roughness on a wall. A new spatial scale which introduced the additional effect of the roughness as the wall friction was used to observe the results of the simulations. As a result, if the height of the roughness was within a certain range of the turbulent boundary layer, according to the new scaling, the characteristics of the turbulence structures corresponded with those of the standard scaling for the case of a smooth wall. This means that, in such cases, the knowledge for wall turbulence obtained in the past studies could be applied to the case of turbulent flow along a rough wall.

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Turbulent flow near a wall is autonomously driven by coherent structures. By sudden disappearance of these structures, turbulence can't be sustained and laminarization is occurred. Using direct numerical simulation, we measure mean lifetimes of localized turbulence in plane channel flow and investigate their dependence on the number of coherent structures by changing the spanwise length of the domain. Consequently the mean lifetime at a certain Reynolds number increases exponentially as a function of the number of coherent structures. This indicates that each coherent structure contributes to the lifetime independently.

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Direct numerical simulation of a spectral method was performed to study the flow structure of the turbulent stripe in rotational plane Couette flows. Through the simulation, the turbulent stripes appear in the near-wall regions, while the turbulence become homogeneous near the channel center. The small scale structure is almost same in the entire channel except wall vicinity consisting of viscous sub-layer and buffer layer. The structures as high- and low-speed fluids are transferred downstream by mean velocity at each y-location, whereas the turbulent stripe moved downstream at constant velocity keeping its shape. Moreover, mean spanwise velocity is generated and is responsible for the decision of the stripe direction in this simulation.

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We perform direct numerical simulation (DNS) for annular pipe flow and report localized structures in subcritical transition. Our flow system is the simplest fundamental annular pipe flow which is a flow between two concentric cylinders and is driven by a constant uniform pressure gradient in the axial direction. By changing Reynolds number (Re_τ = uτδ/ν) and radius ratio (η = r_<in>/r_<ou>) systematically, we found several localized intermittent turbulent states. To observe the effect of η, we choose low to high radius ratios, which are 0.1, 0.3, 0.5, and 0.8. At η &ge; 0.5, we confirmed stripe pattern similar to that in the plane Poiseuille flow. In contrast, with a low η of 0.1, localized structures corresponding to equilibrium puffs and splitting puffs arise. The moderate η of 0.3 gives rise to localized turbulence taking a form of finite (like a puff) and helical shape (like a stripe pattern).

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Direct numerical simulations of Taylor-Couette flow from Re = 8000 to 25 000 have been performed to understand the spectral characteristics of turbulence in the transition of the Reynolds number dependency of the mean torque near Re = 10 000. The velocity fluctuations are decomposed into the wavenumber components, and their contributions in the radial profiles of the Reynolds stress and the transmission of the mean torque are evaluated. In the net mean torque, the contribution of the azimuthally averaged component overtakes that of the remaining turbulent counterparts around Re = 15 000. Therefore, the torque transition can be explained by the competition between the contributions of azimuthally averaged Taylor vortex and the remaining turbulent fluctuations.

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A technique using high-speed infrared thermography was used to measure the spatio-temporal heat transfer to a turbulent water pipe flow around an orifice plate (bore ratio: d/D = 0.49, Re_D &ap; 13000). The spatio-temporal distribution of the heat transfer coefficient was evaluated based on the temperature fluctuation of a heated thin-foil measured using infrared thermography. In this work, we tried to evaluate the convection velocity of the heat transfer structure on the heated surface, which is considered to be associated with the convection of the vortical structure in the near-wall region. As a result, it was confirmed that the maximum position of the heat transfer in the time-averaged distribution was not coincide with the time-averaged flow reattachment position, as reported in the literature. In order to investigate the mechanism of this difference, ensemble-averaged heat transfer coefficients were calculated on the condition that instantaneous reattachment appeared at specific streamwise positions. The ensemble-averaged heat transfer distribution shows a noticeable peak at the flow reattachment position, comparing with the time-averaged distribution. Also, the peak value of the ensemble-averaged heat transfer distribution tended to decrease toward downstream. This trend indicates that reattachment at upstream contributes to the heat transfer enhancement more significant than that at downstream. This is the reason why the maximum position of the time-averaged heat transfer exists upstream of the time-averaged flow reattachment position.

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Turbulent heat transfer in horizontal Couette-Poiseuille flows heated from below is investigated numerically at fixed Reynolds number Re = 2000 and for bulk Richardson numbers Ri = 0, 0.01, 0.1. In this flow system the u_<upper> wall moves at a temporally constant speed u_<upper>, while the lower wall is at rest. For an invariant volume flux and so a constant bulk mean velocity u_b, the upper wall speed is changed in the range of 0 &le; u_<upper>/u_b &le; 2 to establish the Couette-Poiseuille flows. It is found that the dimensionless wall heat flux (Stanton number St) takes a local maximum for a certain value of u_<upper> at which the mean velocity gradient on the upper wall is null. For larger Ri (= 0.1) this local maximum of St is observed to be global.

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The transfer phenomena of wall turbulence are carried by quasi orderly vortex structure, what is developed from small scale vortex near the wall. How to change the turbulent motion and turbulent transfer by modifying the condition of near wall is important for academic and industry like control of mass and heat transfer. In this study, we analyze empirically how to change mass transfer in cannel turbulence by uniform blowing from the wall, what has porous plate. We use PIV・PLIF simultaneous measurement by mixing fluorescent dye in blown fluid to observe spatial situation of mass transfer in turbulence and analyzed from turbulence statistical point of view. As a result, blowing enhanced fluctuation of disturbance and along with it, coefficient of friction and mass transfer rate ware increased. On the other hand, isotropy of turbulence and turbulent Schmidt number are almost no change.

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Direct numerical simulations have been performed for turbulent heat and momentum transfer in porous channel flow, on which similar thermal and mechanical conditions are imposed. On the porous surface the transpiration is assumed to be proportional to the local pressure fluctuations (Jimenez et al. 2001 J. Fluid Mech. 442 89-117). Turbulent heat and momentum transfer is found to be significantly enhanced by the appearance of large-scale spanwise rolls from a linear instability of shear layer over the permeable wall. The physical mechanism of this dissimilarity is interpreted in terms of the relevance of the spanwise rolls with ther induced turbulent heat flux and Reynolds stress. The correlation between the wall-normal velocity and fluctuation streamwise pressure gradient, induced by the spanwise rolls, is shown to play a role in the dissimilar heat transfer enhancement.

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An experimental investigation has been conducted to examine the effects of vortices on turbulent diffusion behind a pyramid placed on the wall in a turbulent boundary layer. Turbulent diffusion process was observed with CO_2 injection near the pyramid. The concentration of CO_2 was detected by RI-85 monitor with Non Dispersive Infrared Radiation technology. On the other hand, the velocity distribution was measured by a single hot-wire with constant temperature anemometer. Gas diffusion without pyramid in z direction is somewhat faster than in y direction. Pyramid can enhance gas diffusion but CO_2 contour map has non-uniform and strong concentration in the cross-streamwise plane behind the pyramid placed with angle of attack at γ=45°. The non-uniform diffusion could be explained with longitudinal vortices generated by the pyramid placed in the shear layer.

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We have constructed an experimental platform by using the precession of a fluid container. This platform is useful to attack various unsolved problems on turbulence such as turbulence modulation due to a small amount of additives, the non-equilibrium statistics of turbulence driven by steady force, and so on.

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By using database of Direct Numerical Simulation(DNS), we analyze the accuracy of the frozen turbulent hypothesis. Reynolds number based on the friction velocity and the channel half-width is 1000. We compare the Pre-multiplied spectrum(PMS) in frozen turbulence and spatial data. It is found that the frozen turbulent hypothesis is approved in the streamwise, wall-normal, spanwise velocity and pressure fluctuation in the region away from the wall.

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Lifetime of transient turbulence in a rectangular-duct with the cross-sectional aspect ratio A = 5 is measured experimentally by using a multi-PIV (Particle Image Velocimetry) system. The survival probability of transient turbulence is observed to decay exponentially as a function of its streamwise position. The comparison of the mean lifetime obtained from exponential fitting of the probability for A = 5 with the former experimental data for A = 3 shows that the mean lifetime significantly depends on the aspect ratio. For a fixed value of the bulk Reynolds number, the mean lifetime in the wider duct with A = 5 is shorter than that in the narrower duct with A = 3.

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A local wall shear stress measurement method is proposed with a thin circular plate submerged in the wall layer. A calibration curve of pressure difference produced by the plate and near wall flow can be correlated with the local wall shear stress by a single analytical function for different plate thickness. For approaching angle of attack to the mean flow, the circular plate has well sensitive in comparison with the rectangular plate.

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Fluid Bed, Technology of drying while fluidizing the powder by blowing the drying gas from a gas distribution plate mounted in the lower part of the box-shaped dryer

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General mixing machine which has rotor with blades have some problems such as influence on mixing fluids by share force at blade tip and occurrence of cavitation at high speed range. In order to solve these problems, the mixing rotor without blades had been developed. This rotor has very simple shape, which has 3 thorough holes in the mixing rotor. In the present study, the numerical analysis and experiment were carried out to obtain the basic characteristics of mixing rotor with holes on columnar shape. In the experiment and numerical analysis, the number of rotation of rotor and kinetic viscosity of working fluid were changed. It was concluded as follows; (1) Outlet velocity is only subjected to number of revolutions. (2) Number of mixing power is smaller than general impeller's when mixing Reynold's number Rem ranges from 50 to 5000. (3) According to CFD, flow field is symmetrical when Rem is low. But, flow field is complicate when Rem is high.

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As a part of the research for developing pitch-adapted marine propellers, a deformable hydrofoil with composite materials was designed and manufactured. Hydroelastic behavior of the deformable hydrofoil were studied in a large cavitation tunnel at the Naval Systems Research Center. Displacements of target points on the hydrofoil were measured using a laser distance meter and a high speed video camera. Measured hydrofoil deformation was in a good agreement with the computations of the fluid-structure coupled analysis.

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This paper presents the results of detailed 3D CFD analyses of the aerodynamic interaction between two MEXICO wind turbines. The interest of this study is focused on the flow field, aerodynamic load fluctuation and performance of the downstream turbine in the wake of the upstream turbine. A CFD analysis code, rFlow3D, developed in Japan Aerospace Exploration Agency (JAXA) is adopted for this purpose. Computations in this paper are conducted using the Quasi-DNS solver because it is well adapted for relatively low Reynolds numbers in the order of 10^5〜10^6. The results show that the velocity fluctuation in the wake and the wake interference ratio dominate the aerodynamic load fluctuation of the downstream rotor. Furthermore, the power change trend of downstream rotor due to the change of the lateral distance between the rotors is also confirmed. The results will contribute to the design guideline of large-scale wind farms.

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A simultaneous optimization method for the aerodynamic design of rotor and wind-lens for wind-lens turbine has been developed. The present optimal design method is based on a genetic algorithm (GA), and optimizes simultaneously blade loading distribution and wind-lens shape. Three-dimensional Reynolds averaged Navier-Stokes (RANS) simulation for the wind-lens turbine designed by the optimal design method has been conducted on the off-designed conditions. The result shows that the wind-lens turbine designed by the optimal design method is superior to the conventional one in the total performance, because of the suppression of flow separation on the inside of wind-lens, the lower stall point, and the smaller difference between design and actual attack angles. The analysis indicates also that the more suppression of flow separation and the less difference between design and actual attack angles raise the performance of wind-lens turbines.

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