Experimental investigation controlling a trailing edge separation on a wing in ground effect is carried out. The Dielectric Barrier Discharge (DBD) plasma actuator with pulse modulated driving is used for the control. As a result, the trailing edge separation is suppressed by means of the plasma actuator, so that the drag coefficient is decreased and lift-drag ratio is increased. The lift-drag ratio becomes maximum when the actuator is located at 75% chord from the leading edge.

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The present aim is to reveal the flow past a rotating ring which is immersed parallel to the mainstream. At first, we conduct field observations of a flying ring using a pair of high-speed video cameras, together with three-dimensional motion analyses based on their recorded images, which quantitatively reveal both paths and angular velocities of the flying ring. In addition, we conduct numerical simulations by a finite difference method, whose results suggest that the ring-rotation effect becomes remarkable for a rotation parameter Ω^* > 0.4. This suggests that the flight at Ω^* ≈ 0.4 is suitable.

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Lift and drag characteristics of a symmetric airfoil with miniature electromagnetic actuators have been investigated when an angle of attack has been increased at a constant speed in a low Reynolds number range. It was revealed that the dynamic actuation of the miniature actuators was effective to delay the stall. A basic example of a feedback control, in which the time series lift was used as the input signal to detect the stall and had a role to start the actuation of the miniature actuators, was tried and it could achieve the increase of the lift, that is, it could delay the stall. Second example of a feedback control including the increase and decrease of the angle of attack of the airfoil was demonstrated to be effective not only to recover the lift after the stall but also to maintain the high lift situation.

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Various blades are used for fluid machinery such as wind turbines and pumps. This report focuses attention on wind turbine blades. Wind turbine generator systems consisting of wind turbines with propeller-type rotors on a horizontal axis employ turbine blades to effectively catch aerodynamic forces commonly represented by lift and drag. The thickness ratio of the blade is small at the blade tip (thin blade) and is large at the blade root (thick blade). The previous paper proposed that placing a cylindrical rod in front of a blade as a simplified stall control method for controlling the flow around the blade and avoiding stall phenomena improved the flow on the upper surface of the blade and extended the operable range significantly until the angle of attack reached the high attack angle region where a stall occurred. In this paper, a cylindrical rod in front of the thick blade was placed to examine the behavior of flow aro und the blade by using experimental and studied the effect of the cylindrical rod on the control of stall phenomena.

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This paper performs a numerical analysis of the throughflow on a 4 stage compressor as a two-dimensional axisymmetrical flow. The treated case is a flow in the low-pressure compressor of core-engine of former NAL's conceptual Jet VTOL aircraft. This analysis regards the flow field as axisymmetric flow and employ two-dimensional conservation Euler's equation expressed as general coordinates. The case of design point calculation is performed to obtain the acceptable blade designs for the compressor.

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Water hummer pump can effectively use the water hammer phenomenon that include pumps and allow fluid transport without drive sources such as electric motors. The results of experiments that examined the effect of the geometric form of eater hammer pumps by considering their major dimensions have been reported. However, these conventional studies have not fully evaluated the pump performance in terms of pump head and flow rate, common measures indicating the performance of pumps. The previous paper experimentally examined how the hydrodynamic characteristics ware affected by the inner diameter ratio of the drive and lifting pipes, the form of air chamber, and the angle of the drive pipe. This paper experimentally examines how the water hammer pump performance is affected by number of spring in drain valve. It also clarifies the behavior of flow in the valve chamber during water hammer pump operation.

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The flow field of the newly developed inflow cannula designed for a bridge-to-decision circulatory support was numerically analyzed by computational fluid dynamics. This new cannula has elastic struts at the cannula tip that enables minimal invasive insertion to the left ventricle, while keeping a wide inflow area by its lantern-like cannula tip. The hydrodynamic loss of the cannula, including the change in pressure loss due to deformation, and the thrombus potential of the cannula were numerically examined. The hydraulic resistance of the cannula with the blood analog fluid was 31 mmHg at the flow rate of 5.0 L/min.

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Nasal continuous positive airway pressure (Nasal-CPAP) is frequently used in the care for the preterm neonates to recruit and maintain the lung volume. The authors have developed Nasal-CPAP device with a bypath type (B-NCPAP) of horizontal type which reduces the breathing work for the neonate. Although we uses it in face up and abdominal position in clinical treatment, a vertical type is more desirable. The fundamental features of B-NCPAP device was tested experimentally. Results show that pressure falls at the time of expiration, and the present device provides a comfortable situation to patient, when it works in inspiration phase especially.

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The purpose of this study is to investigate the characteristic of the thrust for the propulsive nozzle directly driven by the high-pressure air compressed by the self-excited vibration in the blower piping system. The exhaust valve is positioned at the discharge pipe, and both the pressure and the thrust were measured for various parameters such as the number of revolution for the blower, the period of the opening and closing action of the valve, and the depth. The following conclusions were obtained. The dominant frequency agrees with the period of the opening and closing action of the valve. It is important for the rise of the ejection pressure to coincide the period of the wave for the gas-liquid interface and one of the opening and closing action of the exhaust valve.

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At closed water region, sediment transport is mainly caused by wind-induced flow. Such sediment transport does harm to water environment because it causes elution of organic components from sediment to the water body. This study numerically evaluates sediment transport caused by wind. Two-phase flow and mass transport at nearshore region are simulated. Results show wind causes resuspension near the onshore and then suspended sediment moves to offshore. RMS value of cross-shore component of water velocity is large at near shore region. Resuspension sediment flux is also large at near shore. This means velocity fluctuation may cause sediment resuspension.

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To understand the flow physics in a serpentine passage over a porous wall, PIV measurements are carried out. Two kinds of porous media (#06, #20) which have the same porosity but different permeability are used. Flows at Re_b=600, 2700 are considered. It is found that the flow rates in the porous media and the flow motions going in and out of the porous media increase as the permeability increases. In the bend region, turbulence is enhanced by the bend structure, and in the flow after the bend region, it is also enhanced as the permeability increases. Also at Reb-600, longer turbulent flow regions are retained near the bend as the permeability increases because of the presence of the flow motions going in and out of the porous media.

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We attempt to improve accuracy of PIV analysis by introducing an interpolation technique for brightness distribution. This work numerically realizes decrease in uncertainty by introducing an interpolation technique. We select a Fourier interpolation technique as a interpolation technique. First, we confirm that the Fourier interpolation technique can interpolate original brightness distribution well. Then, the effectiveness of this proposed method is quantitatively investigated by using a Monte-Carlo simulation. The results show that uncertainty is decreased by applying the Fourier interpolation technique when diameter of particle image is sufficiently large.

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Pressure sensitive paint (PSP) is a useful noncontact measurement technique to obtain continuous pressure distribution on solid surfaces. The application of PSP to low speed flows in mechanical engineering fields, including unsteady flow measurement related to analysis of aerodynamic noise, is highly demanded. In this study, we clarify the feasibility of PSP as a measurement tool for unsteady low-speed flow fields. Because the response time depends on the square of the thickness of the PSP layer, we have developed the thinner-layer PSP to improve its time response, and the dependence of the thickness of PSP layer on pressure sensitivity and time response was verified. Furthermore we have applied the PSP to measurement of pressure distribution around the circular cylinder in steady flow, to clarify the problems when PSP is applied to measurement of unsteady pressure distribution in low speed flows.

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We develop quantitative evaluation method of airless spray by using entropy of gray scale image. Stroboscopic method is employed to visualize the spray. An undesirable "tail" region of the spray is detected as low image entropy area. As against the conventional visual judgment, the proposed method enables a quantitative evaluation of spray.

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The molecular tagging velocimetry (MTV) is applied to measure the velocity fluctuation in a supersonic micro jet issuing from the two-dimensional Laval nozzle whose height is 500jim at the exit. This velocimetry uses the forth harmonic of a Nd:YAG laser (266nm) as a light source to excite the acetone molecules seeded in the flow, and fluorescence images are captured by a CCD camera 300ns after the laser illumination. A distribution of root-mean-square (RMS) of velocity fluctuation is obtained from these images. The distribution represents well the characteristics of the turbulent micro jet although unreasonable RMS values due to low fluorescence intensity are recognized around the jet. A distribution of single-time two-point spatial correlation is also obtained from the measured velocity fluctuations and this distribution reveals that the micro jet fluctuates in a flapping mode.

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Spectroscopic measurements of arc-heated plasma flow are conducted using a hollow electrode arc heated wind tunnel. The test gases are 100 % CO_2and 95% CO_2-5% N_2 mixture gases which simulate Martian atmosphere. In CO_2plasma, radiation of C_2Swan band system is predominant. Other molecular and atomic spectra are not observed except Cu spectra which are produced due to the electrode melting. In CO_2-N_2plasma, radiation of CN violet band system is predominant as well as C_2Swan band system. Other molecular and atomic spectra are not observed except Cu spectra. Analytical tools were used to determine the following line-of-sight-averaged thermodynamic properties from the calibrated spectra. The rotational and vibrational temperatures were measured by a spectroscopic method.

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In recent years, the number of cars and motorcycles has increased around the world and now reached more than a billion. The environmental pollution is caused by the emission from automobiles, being critical problem. As one of the countermeasures, higher and higher level standards of emissions have been defined in developed countries. Catalytic converters are one of the most important parts of vehicles' emissions control system, its operating temperature being very high. Vehicles emit most of their pollution during the first a few minutes of engine operation before the catalytic converter has warmed up sufficiently to be effective. Therefore, this study focuses on heating the converter up to the operating temperature, using wave phenomena formed in the exhaust pipe. As a result, the temperature and the pressure oscillation in the converter were measured with respect to the revolution of engine and these data Were compared with each other. The intensity of pressure wave in converter was found to be related to the temperature rises.

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The new device which can be switching air flow direction is used for capsule conveying system. This device produces pulsating flows with positive and negative pressure owing to switch the suction and discharge of one blower. Behavior of the capsules moved with those pulsating flows in a pipe is experimentally examined. As a result, the effects of pulsating flows on behavior of the capsules are clear; transfer distances of the capsules depend on the difference between positive and negative pressure acting times, and the larger a mass of capsule is, the later the capsule starts to move.

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In Part 1, the performance of the new device which can be switching air flow direction is tested for capsule conveying system. In this report, behavior of the capsules moved with those pulsating flows in a pipe is examined analytically. As a result, the effects of pulsating flows on behavior of the capsules are clear extensively. The minimum period and minimum peak value of the pulsating pressure for driving a capsule are found, and the relation between transfer distances of the capsule and trapezoidal pressure waves is obviously shown.

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In a petrochemical plant, piping vibrates and often results in the fatigue fracture of connection of tubes. A lot of hydrocarbon gas is formed in the oil refining process in such a plant, which is burned off in the air. The gas is released by pressure valve with a loud noise made, going to a flare stack. The noise has broadband and vibrates pipes, in which the flammable gas flows. This phenomenon is called "Acoustic Induced Vibration", by which a connection of tubes is thought to be destroyed. So far, measures have been given based on a certain standard originated from this thought and the mechanism of destruction does not completely clear. In this research, in order to solve this destruction mechanism, the loud noise was experimentally radiated in a pipe and a mode of vibration of pipe wall was examined. As a result, the vibration was shown to become large at specific frequency.

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Velocity measurements have been done in order to clarify the flow reattachment locations over a 3D backward-facing step in a duct by PIV for low Reynolds numbers 400. The aspect ratio and the expansion ratio of the stepped duct were 16 and 2, respectively. It was found that the reattachment location changes periodically at the center of a duct, and this periodicity becomes weak as it goes from the center to the side wall. At the center of a duct, since both of the clockwise and the counterclockwise vortex generate equally and move toward downstream, the reattachment location appears between them. On the other hand, at the location having a little bit distance from the center of the duct, counterclockwise vortex becomes large compared to that of the center of the duct.

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Injection of microbubbles within water has been investigated for several years as a method to achieve pipe friction loss reduction. However, the physical mechanism of this phenomenon is not yet understood. So, the purpose of our study is to understand the mechanism. We researched pipe friction loss reduction by the experimental device, which was constructed by a circular pipe. Adherence of bubbles to the wall had an effect on pipe friction loss. In the case of void fraction 0.1% ± 0.02%, the effect was shown Re ≦10000, and influenced pipe friction loss reduction. In addition, in the event Re = 5000, 20000, pipe friction loss reduction became enlarged by increasing void fraction. Meanwhile, at Re = 10000, pipe friction loss reduction didn't change widely by increasing void fraction. As the result, void fraction had a relationship with pipe friction loss.

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The micromixer, which has a rotor with a curved channel, is studied experimentally. The secondary flow in a curved channel of rectangular cross-section is investigated using PIV (Particle Image Velocimetry) and LIF (Laser Induced Fluorescence) methods. Two walls of the channel (the inner and top walls) rotate around the center of curvature and a pressure gradient is imposed in the direction of the exit of the channel. The non-dimensional parameters concerned are the Dean number De and the Taylor number Tr. Photographs of the flow in a cross-section at 180° downstream from the curved channel entrance are taken by changing the flux (De) at a constant rotational speed (Tr) of the channel walls. It is found that good mixing performance is obtained in the case of De <__<_> 0.1Tr This tendency appears more strongly if aspect ratio is large.

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An experimental study has been made of the baffle-tube leakage in shell-and-heat exchangers. The discharge coefficients for flow through the multiple annular orifices are same as pressure coefficient for flow through a single annular orifice at Z=29 (Z: orifice shape factor). In the case of Z=67, the discharge coefficients are unsuitable.

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This report describes experimental results of a small scale updraft fixed-bed gasifier for wood chips. The characteristic of wood chips such as size and water content vary depending on how to make chips and state of conservation, respectively. Therefore, it is important to devise the gasification method corresponding to various woody biomass for wide use of woody biomass energy. In order to clarify the effect of wood chips characteristic on gasification, the experimental was performed in different condition in terms of grain size and water content. Fluctuations of temperature distribution, pressure difference between inlet and outlet of reactor, and CO concentration were measured. By using these results, combustion state and construction of wood chips in the reactor were deduced and effects of grain size and water content of wood chips on gasification are discussed.

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The present research presents a new type of thruster that has a nozzle-like, or diffuser-like, configuration, i.e., an asymmetric channel. The fluid in the channel is excited by the reciprocating piston integrated on the sidewall. The experiment and the Computational Fluid Dynamics (CFD) and the one-dimensional(lD) analysis were conducted to investigate the flow characteristics in the asymmetric channels. In the experiment, the Particle Image Velocimetry (PIV) system was used. In the CFD, the ANSYS code was utilized. In the analysis, the one-dimensional analysis was performed with the continuity, the unsteady momentum and the quasi-steady loss equations. The experimental, CFD and analytical unsteady results agree qualitatively well. The mean flow runs from the wide to the narrow and the time-averaged thrusts acts in the opposite direction. The thrusts becomes larger for the 3mm width than for the 24mm one.

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Mixing/diffusion enhancement is one of the key technologies in various aspects, and is needed in chemical reactors, heat exchangers, burners/combustors, low-noise jet engines, air conditioners and so on. Jets are known to be useful for such mixing/diffusion enhancement. The authors research the jet from an asymmetrical two-dimensional nozzle, especially concerning the effect of the lip length of the nozzle. Experiments are conducted at a Reynolds number of 6000. The aspect ratio of the nozzle exit is fixed to 300. And, the lip length is 13h or 10 h, where h denotes the height of the nozzle exit. The authors show mean-velocity and turbulence-intensity profiles at various downstream sections, in order to reveal fundamental characteristics of the jet.

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An experimental study is carried out for dividing flow through 90°T-junction of rectangular cross-section. The Reynolds number based on the mean velocity at the main channel and the hydraulic diameter ranges from 1.5x 10^3 to 6.0x10^3. The flow rate ratio (ratios between the flow rates in branch and main channel) is set at 0.2, 0.4, 0.6 and 0.8. The results show that the loss coefficient of main channel undergo a characteristic change with changes in the Reynolds number and flow rate ratio. The loss coefficient of branch channel is increased with the increase of flow rate ratio, decreased with the increase of the Reynolds number.

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Induced flow fields by a dielectric barrier discharge (DBD) plasma actuator installed on a flat plate in quiescent flow are analyzed numerically. The produced airflow resulting from a simple sine waveform and burst modulations is discussed. The correlation between the operating mode of DBD plasma actuator and the resulting flow: fields generated in temporal and average domains is presented. The generated flow resulting from a simple sine waveform is quasi-steady and fluctuates with base frequency of actuation. On the other hand, the induced flow structure by the burst modulations is unsteady and shows the dependency of actuation modes in terms of instantaneous sense

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Numerical analyses have been performed on liquid-metal MHD flow in a rectangular channel with sudden expansion. The sudden expansion is in the direction perpendicular to the applied magnetic field. Numerical results give negative loss coefficients as was the case of an existing equation based on experimental data. However, the existing equation gives much smaller values (negative but much larger absolute values) than the present numerical analyses. Thus, it is desirable to perform numerical analyses for wider calculation conditions.

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The flow field such that several physical spaces are combined instantly is interesting analysis object in discipline of computational fluid dynamics. So, in this paper, the flow field around an ejection body from the cylinder is computed as an example of above flow field. In this flow field, two physical spaces separated by the body combine due to ejection of the body. However, it is impossible to compute this flow field by using conventional unstructured moving-grid finite-volume method because this method only moves boundaries, doesn't combine boundaries. Thus, in this paper, developed unstructured moving-grid finite-volume method which creates and eliminates computational elements as time passes is applied to this flow field.

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In this study, we aim to simulate blood flow in left ventricle. As a fundamental study, we make the simulation model of displacement pump whose capacity is changed in a cycle and simulate the internal flow using 2-dimentional Navier-Stokes equations and virtual flux method. We simulate three types of the pump, one is symmetric and the others are asymmetric. First, we validate mass conservation in terms of flow rate in all cases. Next, we discuss the influence of asymmetry of the models on internal flow. We find that velocity profile near the outlet and wall share stress on the outlet walls are strongly affected by the asymmetry.

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We have investigated various problems that arise in applying the Brownian dynamics method to a suspension composed of rod-like hematite particles, which have a magnetic moment normal to the particle axis direction. The accuracy and the deviation of simulation results from theoretical solutions have been discussed by comparing with the theoretical results that were obtained by solving the basic equations of the orientational distribution function. The present simulation results can well qualitatively reproduce the characteristics of the negative magneto-rheological effect that was predicted by the previous theoretical investigation.

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Quasi-equilibrium Lattice Boltzmann model (QELBM) has been developed in order to get stable solution at high Reynolds number flow simulation by tuning viscosity ratio, namely, the ratio of bulk viscosity and kinematic viscosity. QELBM uses only two relaxation times and does not need to solve non-linear equation at each grid point to enhance stability, thus the algorithm is simpler than Multi-Relaxation Time model and Entropic Lattice Boltzmann model. However, there is degree of freedom for determining the viscosity ratio and the effect of viscosity ratio on the results has not been known yet. In this study, we investigate the region of viscosity ratio where the calculation becomes stable and the effect of viscosity ratio on flow field in various Reynolds numbers and Mach numbers.

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In present days, in order to reduce environmental burdens renewable energy is paid attention to, and photovoltaic (PY) power generation technique is one of them. In a PV power plant a large number of PV panels are arranged in array toward the sun. As the proportion of the costs of panel support structure and its construction to total costs is large, it is important to reduce the construction cost as well as to ensure safety. Establishment of prediction technique by numerical simulation is demanded, because it is difficult to experiment with whole PV power plant. In this paper the prediction technique by numerical simulation was developed for pressure load which is one of the most important parameter associated with the designing of panel support structure and construction. Wind-force coefficient obtained by present calculation agreed well with experimental results and flow around PV arrays is visualized. Moreover, applying this method to various PV arrays arrangement, wind-force coefficient is predicted and flows around PV arrays are visualized.

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Efficient design of thermal puffer type gas circuit breaker need a detail understanding of the fluid-plasma interaction phenomena associated with the gas blast characteristics. Therefore the main aim of this research is to study the fluid-plasma interaction phenomena based on a High-Order LES turbulence model. The first part of this work deals with basic fluid-plasma interaction phenomena around a converging-diverging type nozzle installed with two electrodes inside to generate thermal arc plasma in the nozzle flow field. In the second part of this work, pressure rise mechanism in a thermal puffer type GCB and related physical behavior is analyzed. The results led to an understanding, that basically fluid-plasma interaction results in sudden expansion of the hot gas which in turn led to the pressure rise in the tank and the transport of thermal and pressure energy is carried out through two different modes, namely the convection and the acoustic mode.

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A thermally-expanding gas flow accompanying significant changes in both temperature and density is simulated using SPH method. Thermal expansion is modeled by changing the diameters of particles according to their temperatures. A convective flow whose local temperature varies, ranging from 300 K to 3,000 K, is successfully simulated.

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In order to apply the lattice Boltzmann method to a flow problem of magnetic suspensions, we have investigated the f1・asibility of the viscosity-modifying method that is expected to・be a technique for sophisticating the activating method of the particle Brownian motion based on fluctuation hydrodynamics. We have addressed a magnetic suspension in thermodynamic equilibrium to clarify the influences of various factors such as the roughness of a lattice system and the volumetric fraction of magnetic particles on the scaling coefficient of viscosity. From the snapshots and pair correlation functions of magnetic particles, it is seen that the viscosity-modifying method can show good agreement with the results of Monte Carlo method in berth quantitative and qualitative points. This good agreement is almost independent of the roughness of a lattice system if a relatively fine lattice system is used.

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In the Tohoku-Pacific Ocean Earthquake, many onshore structures were destroyed by the tsunami, the wave height of which exceeded the conventional assumption. In the future, the reinforcement of tsunami disaster prevention measures w 3 be needed, and the evaluation of inundation height and tsunami wave force on onshore structures w 3 be very important. In this study, a three-dimensional simulation that was developed by the authors and can reproduce the topography, building structures, the water depth was applied t0 Tohoku Electric Power Haramachi thermal power station which suffered serious d"11age by tsunami caused by Tohoku-Pacific ocean earthquake. The run-up process of ts 3 lami, inundation height of the main building was evaluated by comparison with the actual traces of the disaster, and the applicability of the three-dimensional simulation is examined for the evaluation of inundation height on onshore structures.

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In this study, knowing about behavior of virus droplets under the indoor environment by combining droplet nuclei infection. which is difficult to prevent with CFD is the object・In concrete terms, temperature and humidity, radius of virus droplet, viability of virus as parameters which has an influence on behavior and infection of virus introduce into 7[!ransmission Simulation. As a result, many virus droplets are different from airflow under the indoor environment.

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Three-dimensional numerical simulation of a red blood cell (RBC) flowing through a micro orifice is carried out in this paper. The characteristics of the RBC deformation and the pressure loss of the flow are discussed as the flow rate is varied for several conditions. Nonlinear spring network model and immersed boundary method are employed to solve the motion of the RBC membrane and its interaction with the flow. A peak was observed for the deformation index and the pressure loss at the entrance the orifice. In this region, the RBC deforms due to the elongational flow and produces drag forces to the flow together with the blockage effect. The pressure loss decreases markedly as the RBC passes the orifice, and then shows a second peak as the RBC flows out from the orifice. These distributions are attributed to the stress produced on the membrane owing to the membrane deformation, and the obstruction effect of the RBC on the orifice. As flow rate increases, the value of the normalized pressure loss at the first peak increases due to the difference of the deformation degree of the RBC.

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A flowfield including local internal flow is difficult to investigate in both experiment and numerical simulation, even though such flow is significant from the point of engineering, for instance flap and slat of a wing. Recently, this kind of flow can be treated by numerical simulation by using high performance computer with large scaled computational grid. However, the complicated geometry consisting of a number of parts with close distance has difficulty still now especially for the grid generation. In the present study, Cartesian grid method is employed for automatic grid generation for the complex geometry with utilizing cut cell method. The flow solver is going to be applied to the flowfield of flat plates in the vicinity of the wall to capture the flow interaction of the objects.

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Unstructured mesh is often used for a flow field with complicated shaped boundaries . In particular, a polygonal mesh is more flexible and efficient for mesh generation. Thus, in this paper, a new solution adaptive mesh method combined with a polygonal mesh is proposed. In this method, meshes based on pressure distribution are generated and divided like a super-polygonal mesh. An algorithm with generated and divided meshes is discussed and confirmed in this paper. The method is applied to supersonic flow with shock wave to show a efficiency of computation.

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Aerodynamics simulation of a small airplane in acrobatic flight has been simulated using moving computational domain (MCD) method. At present, Digital Flight which is the method of flight test using computer is studied in the world. In our laboratory, the simulation of flow field around an airplane which moves turn flight has been performed as a first step of the challenge toward the realization of Digital Flight. As a next step, the purpose of this paper is to simulate a flow field around a freely-moving small airplane in acrobatic flight. Flow field around the small airplane in acrobatic flight was simulated and shown in detail in this paper.

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Characteristics of a flow field around a wing with surface oscillation are investigated using an immersed boundary method. The immersed boundary method is to represent the effect of an immersed body in a flow by a virtual volume force. In this study, the method is successfully adapted to an unstructured-grid solver "FrontFlow/red" based on the Finite Volume scheme. Low Reynolds number flows, such as flows around Micro Aerial Vehicles and Unmanned Aerial Vehicles, are likely to cause early separation. A possible way to restrict this separation is to apply an oscillatory morphing wing shape. Comparisons between static and actuated simulations indicate that the actuation does significantly reduce separation for low Reynolds number cases.

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Compression wave is generated when a high-speed train enters a tunnel. Intention of micro-pressure wave is roughly proportional to pressure gradient. We are obtain it 3-dimentional large eddy simulation. The train enters to the tunnel at three different tunnel pattern, one is only tunnel, the other pattern is with portal hood without window, and the other is hood with window. This simulation uses weakly-compressible fluid with involvement of viscosity analysis method and sliding mesh method. Analysis result show that hood and window have slow the formation of a compression wave. So, maximum pressure gradient reduce. The maximum pressure gradient is reduced 42% compared to only tunnel and hood with window.

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A liquid film flow on a rotating disk and the scattering behavior are simulated using a three-dimensional incompressible SPH (Smoothed Particle Hydrodynamics) method. The liquid film simply flows out when the rotation is slow, whereas the liquid film breaks up to thin lines and eventually to numerous droplets when the rotation is fast. Those numerical results of the scattering liquid show good agreements with the experimental results. However, the effect of the size of the disk cannot be observed when the disk size is large due to not enough resolutions.

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This paper presents results of flight simulations of a paper airplane in the dynamic motion, where both fluid dynamics and flight dynamics are considered. The flight of six degree of freedom is calculated by use of Moving Computational Domain (MCD) Method. This numerical method can be applied to simulate the dynamic motion of a paper airplane in the physical space without the restriction of region size. In this paper, as a demonstrative calculation, the flight, such as circling movements, of a paper airplane is simulated. The computed results show the dynamics of flow around a paper airplane during the flight.

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In parallel computing, it is important that each core is worked with good efficiency. However, it is difficult to achieve high performance in parallel computing, especially using Unstructured Mesh. In this paper, Cashe Oriented Domain-decomposition Method for parallel computing in MPI parallel environment on Unstructured Mesh is presented. A feature of the method is dividing the computational domain by the size of the cache memory in each core and renumbering of element number. Applying the method, the case of computation using 8 cores on compressible flow around a Concorde like airplane was able to achieve speed-up more than about 24% in comparison with a conventional method.

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