Cavitation Modelling Using Real-Fluid Equation of State

Abstract

The aim of this work is to improve the accuracy of cavitating flow simulations by considering realfuel mixture thermodynamics, like gas (air) solubility and physical property deviations from ideality, and their effects on phase change. In this work, a new fully compressible two-phase six-equations model coupled with Peng and Robinson [1] real-fluid cubic equation of state (PR-EOS) is described. Assuming thermodynamic equilibrium with negligible capillarity, this diffuse interface model has been implemented in the IFP-C3D solver [3], which already includes the Gibbs Energy Relaxation Method (GERM) cavitation model [10]. One-dimensional academic test cases (cavitation-tube, shock-tube) are performed firstly to validate the real-fluid PR-EOS implementation. Comparisons of the numerical results with previously published works are also carried out. Then, the models have been applied to simulate the cavitation phenomenon inside a single-hole nozzle. With phase equilibrium theory, the simulation has proved that increased dissolved gas may facilitate gaseous cavitation and restrict the developing of vaporous cavitation. The effect of dissolved gas on fuel properties has also been presented and discussed using the suggested real fluid model. Overall, the two fluid model combined with real equation of state is able to reveal more physical details about the cavitation process.