A numerical study of the interaction between particles and shock layer applied to Mars reentry problem.

Mars exploration began in 1962 with the Russian space probe « Mars 1 ». Technological advances make possible an exploration by the end of this century. However, several issues need to be addressed. One of them is the presence of dust and water droplets in Mars atmosphere. During reentry, those particles can impact the body, damage the Thermal Protection System (TPS) and increase the heat flux.

To simplify the problem, we only focus on water droplets because water's behavior is well characterized. The aim of the study is to quantify the rate of droplet impact onto the body wall.
A set of equations have been written for both gas and particulate phase and numerical simulations of hypersonic two-phase flows around a generic re-entry body have been performed.

Our model takes into account the influence of the drag force, evaporation and break-up on the droplets, as they are expected to play a very important role on the behavior of the droplets in the post shock zone.

Regarding the spatial discretization, the Eulerian approach is chosen over the Lagrangian one for the sake of numerical efficiency.

A numerical parametric study has been performed, highlighting the predominant influence of the break-up phenomenon on the impact rate.