A Study on the Flow behind a Centrifugal Impeller : 1st Report, Theoretical Calculation Applying Potential Flow Theory and Experiment

Abstract

The two-dimensional potential flow on the blade surface of a centrifugal impeller can be calculated exactly. But no effective method for practical use to calculate the flow at any point in a centrifugal impeller passage seems to have been developed yet. In this paper, the authors show an approximate, but comparatively simple method applying the velocity function method which was developed previously by one of the authors to facilitate the calculation of the flow on the blade surface. Using a free impeller type apparatus, the authors measured the relative flow behind a centrifugal impeller and compared that result with theoretical one. It has been made clear that at a flow rate larger than about half of shockless entry flow rate, the theory expresses the practical flow pretty accurately.