Computational study of the coupling of drift-diffusion, photoionization, and chemistry in a scramjet environment

Both experimental and numerical studies have shown that Nanosecond Repetitively Pulsed Discharges (NRPD) can significantly change the combustion field supported by supersonic streams, allowing access to regimes in terms of Mach number and total pressure that would not be possible with regular combustion. Current methods feature simplified plasma-fluid models, which do not consider the effect of flow non-uniformity on the discharge, and one-dimensional radiation models. We present a more complex way to calculate the plasma-induced heat release and radical yield, which incorporates specific kinetic effects of the plasma and radiation. To study this complex non-linear environment, we use three primary tools. First, this model uses Monte Carlo ray tracing (MCRT) to calculate the effects of photoionization of the discharge. Next, multi implicit spectral deferred correction (MISDC) to couple the drift-diffusion equation and reaction to help reduce the splitting errors since this problem incorporates many different time scales for various components. Lastly, in-situ tabulation (ISAT) to solve the Boltzmann equation helps speed up this computational model. Finally, we consider the effect of photoionization and non-equilibrium plasma generated by NRPD on high Mach number flow in a scramjet environment. This model can investigate multidimensional curved electrodes to see how the electrode shape affects the flow in the combustor.