Simulation of MHD Turbulence-Chemistry Interaction in Supersonic Flow

In order to improve the operational efficiency of scramjet engines, it is necessary to develop new techniques to increase the mixing and flameholding properties at high Mach numbers of current scramjet designs. This paper investigates the high-temperature chemistry and plasmadynamic effects of a discharge arc in a supersonic shear layer. This is the first step in developing a clear understanding of the physics governing flameholding and mixing in scramjets. Magnetohydrodyamic source terms are included in fluid conservation equations and the electron energy conservation equation is added to the solution set. This allows the modeling of additional terms such as Ohmic heating, ionization energy loss, and heat transfer through electron and heavy particle collision. The large-eddy simulation (LES) equations are derived and closed using a local-dynamic kinetic energy model (LDKM). The magnetohydrodynamic LES equations are solved numerically under the low Magnetic Reynolds assumption, and the magnetohydrodynamic subgrid terms are ignored in the current work, although these assumptions can be easily relaxed. A chemical kinetic model proposed by Chul Park, which uses 11 species and 51 reactions, simulates the radical distributions in the vicinity of the plasma. Results for a plasma source in a supersonic flow are discussed in this paper.