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Computational Study on the Design for Fluid Flow in High Angular Velocity Screw Pumps

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Abstract

In this study, a multiphase CFD method is used to analyse fluid flow in a screw pump which rotates at very high angular velocity under cavitating conditions. This model utilizes a homogeneous phase approach, based on volume-scalar-equations and a truncated Rayleigh-Plesset equation for bubble dynamics. The model is implemented in the CFD software CFX. Three variants of screw pumps with different combinations of plain and threaded shrouds are studied for their Net Positive Suction Head (NPSH) required and compared. The three variants are studied under similar conditions, and the pump with maximum available NPSH is found out.

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