A study on the flow pattern and the performance of a high-head axial-flow pump by instantaneous pressure and velocity measurement. (Experimental analysis of pump efficiency)

Abstract

As the continuation of the research to improve the suction performance of a high-head axial-flow pump, composed of tandem impellers (an inducer and an impeller), the present study was aimed to make clear the three-dimensional periodic flow field in the pump. The KIII type pump, a bigger model of the KII type, was constructed and used to examine the flow field, which was measured by traversing a combined five-hole Pitot probe with high-frequency response at the inlet and the exit of each impeller. Adopting the "phase locked ensemble averaging" technique, the sampling date were analyzed with the aid of a digital computer, and the time averaged distributions of pressure and components of velocity with respect to the impeller passages were obtained. Each efficiency of components, such as the inducer, the impeller and the guide vanes was also obtained to evaluate the relationship among them.