Simulation of Ionization and Electronic Excitationin Hypersonic Shock Tube Flows Using DSMC

Abstract

At Japan Aerospace Exploration Agency (JAXA), several sample return missions from deep space have lately been proposed. Since its reentry speed is higher than 10 km/s, flow conditions are not well known due to highly non-equilibrium phenomena within such speed range. A hyper-velocity shock tube (HVST) at JAXA is capable of producing such flows, and thus, in order to analyze hypersonic flows in HVST, we have developed an unsteady DSMC flow solver and carried out unsteady DSMC flow simulations for a 11.8 km/s test case. The computed electron number density was consistent with the estimated value from the VUV measurement in HVST, and the DSMC results show thermally non-equilibrium conditions in the downstream region.