The evolution of nitric oxydes in exhaust jets of aircraft engines is studied by direct numerical simulations. An extended Zeldovich mechanism models the chemical reactions far from equilibrium. For O and O2 molecules equilibrium is assumed. The NO formation can be studied as a function of different parameters e.g. expansion ratio, jet temperature or jet Mach number. The chemical reactions are highly temperature-dependant leading to high reaction rates in the hot regions behind strong shocks. In particular nearly all NO is formed behind the central shock in the first shock cell. It turns out that for jet exit temperatures of T < 2000K only negligeable NO-formation in the jet is observed. The NO formation is significant only in hot jets with high expansion ratios.
Pre-equilibrium radial flow from central shock-wave collisions in AdS 5