Validation of DSMC Hard Sphere Model on Hypersonic Shock Interaction

The effect of Kn number and the number of simulation molecules for Direct Simulation of Monte Carlo (DSMC) is investigated in hypersonic double-cone flow and Edney's type IV shock interaction. Hard sphere (HS) model is selected as molecule model and at least 25 simulation molecules are initialized in each upstream cell. Comparisons between DSMC and experiment were conducted. Investigation of double-cone hypersonic flow shows that hard sphere collisions model can predict the trend of pressure coefficient and Stanton number. Investigation on type IV shock interaction shows that the agreement between DSMC simulation and experiment is generally good in hard sphere model. Both double-cone flow and type IV shock interaction simulation reveal that DSMC error depend on Kn Number and models employed for intermolecular interaction. With the Kn number and numbers of simulation molecules increasing, DSMC error is decreasing. When Kn number is more than 8.0 x 10(-5) and the numbers of simulation molecules is more than 25 in each cell for initialization, DSMC error for pressure coefficient, Stanton number and scale of interaction region is controlled within 10%.