DNS of reacting hypersonic turbulent boundary layers

A direct numerical simulation (DNS) approach is used to simulate boundary layers at supersonic speeds. The computational method is validated by comparison with experimental results of a Mach 0.3 turbulent boundary layer. Non-reacting supersonic turbulent boundary layer simulation parameters, such as the mean velocity, shear stress, structure parameter, and turbulent intensity, are found to be in agreement with experimental data. A Mach 4 turbulent boundary layer is simulated, which is represents a 26° wedge at a Mach number of 20 and 20 km altitude. In this case, the boundary layer temperature is high enough to induce chemical reactions. The endothermic chemical reaction that we simulate significantly reduces the temperature fluctuations in the boundary layer. The spanwise and wall-normal Reynolds stresses and the shear stress are increased. In addition, the pressure dilatation increases by an order of magnitude.