High-speed leading edge problem

Abstract

The sharp leading edge problem has been studied for both monatomic and diatomic gases using the Boltzmann equation with the Bhatnagar-Gross-Krook type models as the governing equation and the discrete ordinate method with a closed-boundary value approach as a tool. Plate length relative to the freestream mean free path is taken to be 52. The gas-surface interaction law is assumed to be diffuse reflection. The local distribution functions of molecular velocities and internal energies (for the diatomic gas) for the entire flow field have been calculated for M ∞ = 6.1; thus, the complete flow field has been determined for Tw/T0 = 0.11 and 0.18. Comparisons are made between the calculated results and experimental data. It should be pointed out that the present theory provides a technique to calculate not only gasdynamic variables such as density, flow velocity, pressure, and temperature, but also the nonequilibrium distributions of molecular velocities and internal energies that are very useful in the determination of nonequilibrium radiation intensities.