Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published December 1, 1975 | public
Journal Article Open

Unsteady Flow in Cavitating Turbopumps


Unsteady flow in a cavitating axial inducer pump is analyzed with the help of a simple two-dimensional cascade model. This problem was motivated by a desire to study the effect of unsteady cavitation on the so-called POGO instability in the operation of liquid rocket engines. Here, an important feature is a closed loop coupling between several different modes of oscillation, one of which is due to the basic unsteady characterisitcs of the cavitation itself. The approaching and leaving flow velocities up- and downstream of the inducer oscillate, and the cavity-blade system participates dynamically with the basic pulsating flow. In the present work, attention is focused on finding a transfer matrix that relates the set of upstream variables to those downstream. This quantity, which is essentially equivalent to cavitation compliance in the quasistatic analyses, is found to be complex and frequency dependent. It represents the primary effect of the fluctuating cavity in the system. The analysis is based on a linearized free streamline theory.

Additional Information

Contributed by the Fluids Engineering Division and presented at the Cavity Flow Symposium, Minneapolis, Minn., May 5-7, 1975. Manuscript received at ASME Headquarters, February 5, 1975. This work was supported by the National Aeronautics and Space Administration (Contract NAS 8-28048).


Files (1.4 MB)
Name Size Download all
1.4 MB Preview Download

Additional details

August 22, 2023
October 13, 2023