Evaluation of SCIROCCO plasma wind-tunnel capabilities for entry simulations in CO2 atmospheres

A high-enthalpy wind-tunnel, named SCIROCCO, has been developed in order to perform tests related to the design and the development of thermal protection systems for atmospheric entry vehicles. The main interest of this numerical study is to investigate the capabilities of this facility to simulate flight conditions during entries into planet atmospheres containing CO2. The objective is to estimate the performance map obtained on a sample in the facility test chamber. The flight values of these parameters need to be duplicated during ground tests of the thermal shield protecting the probe. First, a study at equilibrium of the mixture composition for a range of temperatures and pressures has been performed. Then, numerical simulations of the flow along the facility nozzle have been undertaken using a quasi one-dimensional method at equilibrium and a non-equilibrium Navier-Stokes solver. This has determined the theoretical performance envelope of the facility for a CO2 atmosphere. The mass fraction of CO, a highly toxic explosive gas, in the test chamber has also been estimated.