The sewage pumps are demanded a high pump efficiency and a performance in passing foreign bodies. The authors developed the new type impeller which balanced high efficiency and high passage performance so far. However, the impeller used by these usages demands the large passing particle size (minimum particle size in the pump). Therefore, it is very important by the design of these pumps to understand the influence that impeller outlet width gives to pump performance and a radial thrust. This study examined the influence that the impeller outlet width of singleblade centrifugal impeller with a helical spiral suction flow channel gave to pump performance and a radial thrust experimentally. As a result, if impeller outlet width becomes large, time averaged radial thrust decrease at low flow rate, but fluctuating component of radial thrust increase, and fluctuating component of radial thrust does not change at high flow rate, but time averaged radial thrust increase. Therefore, it was made clear that the maximum of the radial thrust did not almost change at all flow rates.

View full abstract