Numerical Study of Non-Equilibrium Air Dissociation for Calculation of Electron Density in Hypersonic Flow

A CFD technique is described in which the finite-rate chemistry in thermal and chemical nonequilibrium air is fully and implicitly coupled with the fluid motion, developed for use in hypersonic flight speed range. Air is modeled as having seven chemical species (N2 , O2 , N, O, NO, NO+, e-) and seventeen reactions. The governing equations are taken to be two-dimensional, compressible, Reynolds-average Navier-Stokes equations and species transport equations. The transient solution to the resulting system of equations is obtained using L USSOR scheme and solved by a full-block matrix inversion. The method is applied to calculate environment of a blunt body with nose radius of circular nose body Rn = 0.3048 m and angle of the base nose θb = 0° flying at hypersonic regime. Computed results are compared with existing experimental and numerical results of other researchers.