Finite-difference calculation of hypersonic wakes

Abstract

A finite-difference method is used to solve the system of equations governing the hypersonic air wake with nonequilibrium chemistry; both laminar and turbulent transports are considered. Numerical results for laminar flow are compared with results of an integral method. Additional calculations for turbulent flow are presented to show some effects of the oxygen-electron attachment process in the far wake, and of the choice of the model of turbulent diffusivity. Nomenclature Cp = specific heat D = vehicle base diameter L = Lewis number h = enthalpy h° = enthalpy of formation P = pressure Rt, = vehicle base radius T = temperature U = X component of velocity U = velocity defect V = Y component of velocity Wi = net rate of generation of species i X = stream wise coordinate Y -radial coordinate a = mass fraction du -velocity radius rj -density transformed radial coordinate a = Prandtl number n = viscosity p = densitŷ = stream function Subscripts 0 = evaluated on wake axis Y = ^ = 0 e = evaluated at edge of wake, or freestream i -refers to species i Superscript ( ) = mass-averaged quantity