極低比速度遠心ポンプの高性能化に関する研究開発

抄録

This paper presents study for high performance of very low specific-speed centrifugal pump. The disc friction loss is one of the main causes of the performance degradation of the very low specific speed centrifugal pump. In order to examine the influence of the number of the balance hall giving a leakage flow to back shroud clearance, its number was changed with 4,2,1 and numerical flow analysis was performed. With a decrease in number of the balance hall, the flow rate in the impeller decreased, and the head increased. On the other hand, the shaft power did not change much, and therefore the efficiency was increased. Consequently, the highest efficiency was obtained in one balance hole, it was improved up to 2.7% efficiency.