Chemical nonequilibrium inviscid flow over a blunt cone at incidence

Abstract

Using a finite volume computational technique, we have investigated the chemically reacting inviscid flow of pure nitrogen over a blunt cone (half angle 13.5 deg) at an incidence of 30 deg. Although the effects of viscosity have been disregarded, the flow is three dimensional and contains a complex shock-vortical structure on the leeward surface of the blunt cone. We selected constant freestream conditions to correspond to those typical of the test section of ground based experimental facilities capable of producing strong dissociation effects. A range of cone sizes has been studied to produce flows ranging across the non-equilibrium regime as well as the limiting cases of chemically frozen (perfect gas) flow and flow that is in chemical equilibrium throughout. We found that the pitching moment coefficient on the body is a strong function of the degree of bluntness and that there are small but significant chemical effects superimposed on the bluntness effects. The effect of chemistry is most complicated for the bluntest body. There are strong chemical effects on the leeward flow.