J0501-4-4 Specific Speed Adjustment Method for Blade Design of Axial Flow Pumps

Abstract

We developed a new method for controlling specific speed at best efficiency point of axial flow pumps. This method introduced two scalar parameters for adjusting a blade surface globally, one is the total curvature of blade camber surface, and the other is blade setting angle. The total curvature represents strength of blade surface curving and controls pump head. The blade setting angle determines blade inlet attack angle and controls a flow rate characteristics. Changing both parameters at once, we control the specific speed of the pump best efficiency point. If we modify the total curvature of blade surface with keeping its curvature distribution similar, we can change specific speed without major deterioration of pump efficiency. Because the controlling method is simple and efficient, we can also reduce the duration and cost of the blade design and optimization process.