An improved theory for regenerative pump performance

Abstract

Owing to their low specific speed, regenerative pumps allow high heads with small flow rates and have performance curves with very stable features. This kind of pump is also smaller and simpler to construct than the other equivalent volumetric pumps, although it has fairly low efficiency. Over the past few years, regenerative pumps have been subject to more interest in various industrial applications. Previous mathematical models do not describe the flow characteristics very well as they are based on simplified assumptions. An improved model is proposed in this paper for the pump performance. The model can handle one inlet angle and two exit angles for the impeller blades and it can be used for the design of twisted blades that would increase the pump head and efficiency. A new feature of the pump characteristics based on the proposed model is discussed. It is shown that the proposed model yield results that are in good agreements with the experimental results. The new model also shows that the side-blade exit angle has a major effect on the performance of regenerative pump, which has not been accounted for in the previous theory.