Effects of splitter blades on the flows and characteristics in centrifugal impellers

Abstract

Flow measurements were made in an unshrouded and a shrouded impeller with splitter blades by using a five-hole pressure probe. The passage flows and characteristics of these impellers were compared with those of impellers without splitter blades. In the pressure-sided passages of impellers with splitter blades, the wake positions are similar to those in impellers without splitter blades. In the suction-sided passages of impellers with splitter blades, the wakes of the unshrouded and shrouded impellers occur on the suction surfaces, but the relative velocity at the unshrouded impeller exit is smallest around the middle blade-to-blade position near the casing. In impellers with splitter blades, the blade loadings tend to become smaller, and the absolute circumferential velocities and total pressures become considerably larger than those in impellers without splitter blades. However, the effect of the splitter blade on static pressure differs between the unshrouded and shrouded impellers.