Direct simulation of a 1-D shock with state-to-state rotational energy exchange

Abstract

One-dimensional Mach 3.5 and Mach 5 shocks are modeled in para-hydrogen (p-H2) using a Direct Simulation Monte Carlo (DSMC) method with quantum state-to-state collision cross-sections. NonBoltzmann rotational population fractions were observed within the shock. The results are compared to a DSMC code using a Borgnakke-Larsen (B-L) energy exchange model. Both constant and temperature variable rotational collision numbers were used in an attempt to match the behavior shown by the quantum state-resolved calculations. The B-L model with constant rotational collision number energy exchange generally failed to match the state-resolved calculations. A modified B-L model with temperature dependent collision number was also tested empirically to see if a better match could be obtained with the state-resolved calculations.