Three-dimensional DSMC calculation and heat transfer analysis of four capsules for hypersonic rarefied conditions

Hypersonic rarefied flow field of four vehicles (Apollo, Orion, Mars Pathfinder and Mars Microprobe) in the atmosphere of Earth and Mars was calculated using the DSMC(direct simulation Monte Carlo) source code compiled by us. Detailed aerodynamic coefficients and thermodynamic coefficients of these vehicles under 42 conditions (with the altitude from 250km to 90km, attack angle from 45° to -45°, Knudsen number from 111.0 to 0.0057, velocity from 7.6km/s to 9.6km/s for the Earth atmosphere; with the altitude from 141.8km to 80.28km, attack angle from 45° to 0°, Knudsen number from 100.0 to 0.0546, velocity from 7.47km/s to 6.908km/s for the Mars a tmosphere) were presented and compared with flight data announced by other countries and calculation results published by NASA (National Aeronautics and Space Administration) Langley Research Center. The results are satisfactory. Three-dimensionless parameters were used to describe the characteristics of thermodynamic non-equilibrium, chemical non-equilibrium and wall heat flux of these four typical vehicles respectively. These results are quite useful for thermal protection design of spacecrafts.