A Barotropic Cavitation Model with Thermal Effects

Extending Brennen’s original formulation [1], this paper illustrates the development of a modified bubbly isenthalpic flow model that naturally accounts in an approximate but physical-based way for the effects of thermal cavitation and the concentration of active nuclei. The model allows for the closed form evaluation of the sound speed in the cavitating mixture, with regular transition to the sonic speed in the liquid at zero void fraction. Numerical integration from the saturation conditions then leads to the barotropic relation for the cavitating/fully-wetted flow, depending on the value of the pressure. Speed of sound curves for three different liquids are shown (water, LOX and LN2), highlighting the influence of thermal effects at different temperatures. The model is then applied to the numerical simulation of cavitation on axisymmetric headforms and 2D hydrofoils. The results are compared with available experimental data with the purpose of assessing the potential of the proposed model for engineering simulation of more complex cavitating flows with special emphasis on liquid propellant rockets applications, where thermal effects are often of crucial importance.