The shear-force pump utilizes the viscous properties of real fluids, and the idea to use shear force in turbomachines is not new. However, if the system size is reduced, it cannot work efficiency in order to increase of friction losses. The purpose of this study is to produce a new type shear-force pump with a highly efficient rotor that we can apply to a micro pump. It is 50mm in a rotor diameter. Experiment was carried out by the measurements of the pump performance and the tangential velocity fluctuation of the flow on a rotating disk. It was seen that the shear-force pump is a highly efficient in comparison with that of a plane rotor pump as usual. It is η≅60% in the maximum total pump efficiency at the flow rate Q=300ml/min and the total head H=1.5m on the rotating speed N=3000rpm. The prediction performance that it can apply to a micro pump was given by these experimental data based on the analogy.

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Fine spheroidal graphite cast iron (FCD-M) has some superior features. One is high tensile strength and fatigue crack propagation resistance. The other is a good molding nature, such as shape accuracy, compared with another cast or forged iron materials. For the purpose of applying FCD-M to axial-flow fan blades, test blades made of FCD400M were manufactured and investigated to obtain strength properties and profile accuracy. Because these results satisfied design criteria, FCD400M were practically used to rotor blades for axial-flow fan. The axial-flow fan with FCD400M blades showed almost the same performance (P-Q characteristic curve and efficiency) as a fan with NC machined blades.

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