Observations of Unstable Cavity Fluctuations in a Rocket Turbopump Inducer

Abstract

The regions of cavity fluctuations in an inducer were investigated with three different types of housing : modified, original and straight. The region of rotating cavitation with modified or straight housing shifted to a higher flow rate range than that with original housing. Some results of visual observations suggested that the reversed flow aroud the tip of the inducer inlet is related to this phenomenon. The rotating cavitation velocity ratio seemed to approach 1.0 as the magnitude of shaft vibration increased. Another rotating cavitation was identified at a lower cavitation number than that at which attached cavitation occurred.