In a radial turbine for automotive turbocharger, variable nozzle guide vane is an indispensable component to achieve high aerodynamic performance over the wide operating range. By changing the nozzle throat area, it is enabled to ensure optimum operation of the engine. However, aerodynamic excitation forces caused by wakes behind the nozzle vanes have become issue as High Cycle Fatigue. In this paper, three-dimensional numerical simulations were performed for three types of nozzle opening angle accompanied with the turbine impeller, in order to estimate the unsteady aerodynamic forces acting on the impeller blades. It was verified that excitation forces could become large around the leading edge of the blade, especially in the case of middle nozzle opening condition. Besides, pressure distributions were highly distorted near shroud and hub sides due to nozzle tip clearance flows. It was confirmed that large-scale and complicated pressure fluctuations were produced on the impeller blade by the wakes depending on the nozzle opening angle.

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Cavitation erosion tests were carried out on fiber-and particle-reinforced composites for repairs; four GFRP（Glass Fiber-Reinforced Plastic）test pieces with different laminate structure and four PRP（Particle-Reinforced Plastic）test pieces with different composite structure, and the relationship between cavitation erosion resistance and structural property was examined. Resistance to cavitation erosion for GFRP test pieces was higher than that of matrix resin of GFRP without glass fiber, Cavitation resistance of GFRP decreased with Shore hardness. Cavitation-erosion resistance of PRP test pieces was lower than that of GFRP test piece with top and surface coating.

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The spiral water turbine（screw-type turbine, spiral water mill）has a runner whose shape is the same as that of Archimedes pump. As this turbine can run on the very low head situation, and it can be very easily set to open water channel, it is suitable for the very small hydraulic power generating. In this study, the internal flow and its relation to the generated power are analyzed both by model experiment and by CFD. The CFD result agrees very well with that of model experiment, assuming the torque at free runner status. A formula to estimate the performance of this turbine is proposed, which is based on the momentum equation of fluid.

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In recent years, there has been a rapid development of wind farm. It is important to investigate the wind turbine arrangement in wind farm, especially with a high turbulence intensity found in the complex terrain. Therefore, by varying turbulence intensity with active turbulence grid, a wind tunnel experiment with two model wind turbines was carried out. The velocity distribution of rotor wake and power output and blade flapping moment of wind turbine in the rotor wake are measured. These measurements show that as increase of turbulence intensity of the inflow the velocity in the rotor wake recovers rapidly and power output of the turbine in rotor wake recovers. Furthermore, the blade flapping moment of the rotor in wake becomes smaller as increase of turbulence intensity. Higher turbulence encourages the admixture of rotor wake and free flow and it weakens the velocity gradient at the edge of rotor.

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In recent years the fan heater used for industry and residence has become smaller, lighter, and more silent as the result of improvement. However there are problems that the fan heater size is still very large, and the noise is very high due to air pressure loss of heat exchangers. Therefore we have been developing the centrifugal type fan with the function as heat exchanger. The features of this new type fan heater are that the fan heater size is very small and silent because the fan and the heat exchanger are in one body. This paper described the thermal flow characteristics that relationship exists between internal flow and local heat transfer coefficient, of the centrifugal fan with the function as heat exchanger that has 12 blades. The heat transfer characteristic was clarified by measuring heat flux and blade's surface temperature. Internal flow was clarified by numerical simulations using Front Flow／Blue.

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Unsteady flow field and noise characteristics of a small axial flow fan used in narrow spaces are experimentally studied. To simulate the flow field in narrow spaces, a flat plate is placed at a certain distance downstream of the fan outlet. By varying the spacing between the plate and the fan, the blockage effect on the fan exit flow and the associated noise level is investigated. The flow field at the location of 3mm downstream of the fan casing in the axial direction is measured using a three-dimensional laser Doppler velocimetry. As for fan noise, the tested fan is installed in an anechoic room, and the noise is measured with a microphone located 100mm upstream of the fan inlet. The experimental results show that the flow field downstream of the axial flow fan and the fan noise change significantly in accordance with the spacing between the fan exit and the blockage plate.

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