Kinetic theory of the sharp leading edge flow of weakly ionized gases

The rarefied flow fields near a sharp leading edge of a flat plate immersed in a weakly ionized supersonic argon were analyzed theoretically. The BGK kinetic equations were solved numerically and the behaviours of neutral and charged particles in the region very near to the leading edge were obtained. Also, the detail structures of a shock wave and a boundary layer were made clear through the present analysis. The calculated density profiles for both neutral and charged species showed the shock formation processes in the leading edge region. The temperature of ions did not differ very much from that of neutral particles throughout the whole flow field. The calculated slip velocity and the shock wave shapes agreed reasonably well with the experimental results obtained from the low density arc heated wind tunnel. (author)