Using a Jet Pump To Alter the Inlet Swirl of a Turbopump

An analysis of empirical data on low-frequency oscillations in the inlet flow of a turbopump has led to the conclusion that these oscillations could be reduced or eliminated with suitable design of a jet pump to alter the inlet swirl. The oscillations in question are of fluid-dynamic origin and occur in the absence of externally supplied excitation, are related to cavitation, and are of approximately constant frequency and amplitude. They are undesired because they give rise to instabilities that can be transmitted to the thrust-chamber stage of the turbopump.