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	Turbulence - shockwave interaction Development of next generation hypersonic passenger aircraft is being promoted in JAXA. For realizing the hypersonic aircraft, the sonic boom(shockwave) is a serious issue. Therefore, it is important to clarify the mechanism of interaction between atmospheric turbulence and shockwave. We are measuring the property of turbulence affected by shock wave in the large wind tunnel. Using PIV(particle image velocimetry), we measure the instantaneous velocity field at the exact moment a shockwave propagates through the turbulent field.→Detail
	Fractal grid turbulence In this study, we clarify the property of turbulence generated by fractal grids. From our experiments, following distinctive properties, which are not confirmed in regular grid turbulences, were revealed: 1.strong turbulence intensity, 2. constant length scales in the downstream direction, 3. non-equilibrium energy cascade. By using these properties, we aim at developing efficient industrial devices.→Detail
	Scalar mixing in grid turbulence For the effective scalar (mass and heat) mixing, taking advantage of turbulence is very important. In this study, we are investigating basic properties of scalar transport in grid turbulence or turbulent shear flow. We simultaneously measure two dimensional velocity and concentration fields in a water tunnel using PIV-PLIF system. In addition, detailed turbulent structure are being investigated using DNS(direct numerical simulation).→Detail
	Chemical reaction in planar jets Chemical reactions occur with turbulence in chemical plants, rivers, oceans and so on. For precise prediction of the reaction products, we need accurate prediction model which takes account of both of chemical reaction and turbulence. In this study, we are clarifying the detailed mechanisms of chemical reaction especially at turbulent/non-turbulent interface in turbulent jet from the sophisticated experiments and numerical simulations.→Detail
	R&D of zinc anode batteries Zinc battery is one of the potential alternatives for large-scalebatteries. However, short life cycle due to non-unifrom electrodeposition of zinc on charging prevents from its commercialization. In this study, we enabled in-situ measurement of zinc concentration near the zinc anode by applying background-oriented Schlieren (BOS) technique. We are trying to suppress the non-uniformity by controlling the mass transport of zinc ion by some methods such as flowing electrolyte.→Detail
	Flow control of round jet by vortex generator Control of mixing and diffusion in jets is very important in many industrial applications. In this study, we control jet mixing and diffusion by inserting small vortex generators in the shear layer. We found that this technique enhances entrainment in upstream region and suppress entrainment in downstream region.→Detail
	Wall shear stress measurement by MEMS sensor Measurement of wall shear stress gives us a lot of information on drag forces in turbulent boundary layer, flow separation point, and so on. In this study, we are developing thermal-type micro sensors with sufficiently high spatial and temporal resolutions using MEMS techniques.→Detail
	Momentum and heat transport in planer jet It is well known that there exit large coherent structures in turbulent planer jets. In this study, we clarify the contribution of the large coherent structures to transfer of momentum and heat in a turbulent planer jet. This study can lead to development of efficient air-conditioning equipment etc.. We are also making a new probe for simultaneous measurement of velocity, temperature and static pressure.→Detail
	Blood flow in a cerebral aneurysm and stenting Rupture of cerebral aneurysms is one of the major causes of death. From previous studies, it is found that development and rupture of the aneurysm have a relationship with flow dynamics of blood in the aneurysm. In this study, we deal with this problem from the point of view of fluid engineering. From experiments and numerical simulations, the wall friction fluctuations are measured in the aneurysm. In addition, we propose new stents which shape is optimal for forming blood clot and suppressing the growth of the aneurysm.→Detail
	Noise reduction in a multiblade fan These days, aeroacoustic noise from car air-conditioners attracts increasing attention with development of quiet hybrid engines. Aeroacoustic sound is generated from turbulence in separated/reattachment flow between blades. In this study, we clarify the mechanisms of sound generation from the flow by simultaneous measurement of sound pressure, air velocity, and wall pressure between an enlarged model blades. In addition, we use numerical simulation to get the visual information of flow field between blades.→Detail
	Mixing and diffusion in coaxial swirl jets In pulverized coal combustion, fuel (coal particles) is provided into the combustion chamber by a round jet while the air is provided by a swirl jet. The interaction of these flows primarily contributes to mixing of fuel and the air and mitigation of toxic gases. However, these flows are optimized empirically due to the complexity of the phenomena. In this study, we investigate the flow structure and mixing by both experiments and simulations to achieve logical control of the flows.→Detail
	Large structure in turbulent boundary layer Drag force on a moving body in fluid depends largely on the states of turbulent boundary layer on its surface. These days, it is pointed out that there exists very large scale motions in turbulent boundary layer at high Reynolds number. In this study, we try to clarify properties of the very large scale motions in a wind tunnel through multi-channel hot wire anemometry.→Detail