Vct pump impeller having monotonically decreasing head with increasing flow rate

Abstract

A shroudless vertical turbine pump (VTC) impeller and method of design thereof minimizes or eliminates discharge recirculation on the shroud sides of the impeller blades, thereby providing a monotonically decreasing head as a function of flow rate from zero flow to a flow rate that is beyond a best efficiency point (BEP) flow rate, and in embodiments beyond 120% of the BEP. Each blade of the impeller has S-shaped mean and shroud streamlines having inflection points located between the exit gate and the terminating edge. The disclosed method comprises varying locations of the inflections points for candidate designs and applying computational fluid dynamics (CFD) to determine successful candidates that meet all application requirements while providing a monotonic head/flow curve. In embodiments, this process is continued until an optimal impeller design is identified, for example a design that optimizes power, energy efficiency, and/or NPSHR.