Role of Non-condensable Gas in Cavitation Inception

Cavitating flows are ubiquitous in engineering and science applications. While many aspects of cavitation inception for pure fluids are well understood, less is known about cavitation of fluids that contain dissolved non-condensable gas (NCG). We investigate two-component flows, where one of the components is a NCG, and the other component can undergo liquid-vapor phase transformations accompanied by changes in its miscibility with NCG. We propose a continuum model derived from a cubic equation of state and the Navier-Stokes-Korteweg equations. The model is derived from fundamental principles using the Coleman-Noll approach. One of the outcomes of the modeling approach is that the diffusion coefficient of the NCG depends on pressure.. The phase diagram is constructed using isochoric thermodynamics to show that the model can capture the miscibility contrast of NCG in vapor and liquid phase. We plot the critical bubble pressure as function of radius and compare the result against experimental data. Further, we study the dynamic dissolution of a spherical bubble and compare our results with the classical work of Epstein and Plesset.