A sharp-interface method for computing the shock-induced evaporation rate of droplet

Shock-induced evaporation of droplets governs the rate of combustion and subsequent deposition of energy in scramjet engines, rocket motors, heterogenous explosions etc. Therefore, it is important to accurately predict the evaporation rate of the droplets during interaction with shock waves. In this work, a sharp-interface method is developed to calculate the evaporation rate of the droplets. The level-set method is used to track the liquid-gas interface. A robust ghost fluid method is developed to couple the flow fields of the liquid and the gaseous phase at the interface. A modified interfacial Riemann problem is solved at every point on the interface to account for the jump in the pressure and the normal velocity fields due to surface tension and evaporation. The tangential components of the velocity fields for the ghost fluid are obtained such that the jump in the stresses at the interface due to the Marangoni effect is respected. The current sharp-interface method is validated against analytical solutions of 1-D Riemann problems and experimental studies of shock interaction with water-column. Subsequently, simulations of shock-droplet interactions are performed to estimate the shock-induced evaporation rate of the droplets.