Characteristics of Thermal Cavitation on a Two-Dimensional Hydrofoil

Abstract

Cavitation in cryogenic rocket propellants was simulated using a surrogate fluid exhibiting thermodynamic properties similar to liquid hydrogen. A NACA 0015 hydrofoil was chosen to represent the leading edge of a turbopump inducer, and it was installed in a closed-loop facility filled with a fluid that exhibits a strong thermodynamic effect at ambient conditions. Static pressures were measured at seven locations along the hydrofoil chord and along the wall of the test section. Flow at Reynolds numbers up to and temperature high enough to produce above unity exploited the thermosensitive properties of the surrogate fluid. Sensitivity to isolated effects of velocity, cavitation number, temperature, and angle of attack were studied, and behavior of the cavity growth and collapse cycle is described. Cavitation was observed at local static pressure both above and below the vapor point corresponding to the inlet temperature. Pressure and frequency analysis of these phenomena is described.