抄録
It is considered that the lower limit of specific speed for a centrifugal pump is 80(min-1, m3/min, m). A centrifugal pump with a much lower specific speed than this has been developed. In this development, a combination of trial calculation using a method of performance estimation for an impeller and the idea to ditch the spiral grooves on the impeller to maintain adequate tip clearance was adopted. The result of tests using two kinds of impeller shows that the maximum efficiency of both impellers is 28% and 25%, and that the specific speeds at that point are 55.7 and 51.0, respectively, even though it is a palm-sized pump. Moreover, the noise level of both impellers is 52 dB (A).
