A theoretical analysis of alternate blade cavitation in inducer

Abstract

An analysis of steady cavitation on flat plate cascade is performed by a singularity method based on closed cavity model. As a result, it is found that two kinds of the steady cavitation patterns exist. One is equal length cavitation in which the cavity lengths of all blades are the same. The other is alternate blade cavitation in which the cavity length changes alternately from blade to blade. Although the present model fails to predict the range of cavitation number where alternate blade cavitation occurs, it predicts alternate blade cavitation in terms of cavity length fairly well. The static pressure losses in both the equal length cavitation and the alternate blade cavitation are estimated. A parameter study is carried out to educe the general characteristics of alternate blade cavitation.