Advanced simulation and experiments on dynamic weakly-ionized plasma, with MHD and non-equilibrium chemistry

An overview of recent efforts at developing a high-fidelity simulation tool for dynamic weakly ionized plasma phenomena is presented in this paper. The work also has an experimental component intended to provide extensive validation data. The various models investigated are physics-based, and are cast in a form that was incorporated into AEROFLO, which is a high fidelity CFD software tool developed by TTC Technologies, Inc. As a first step, magnetohydrodynamic (MHD) models were validated with experimental data obtained at the Ohio State University (OSU). The implementation of a generalized boundary condition framework for the MHD variables, conductivity, electric potential and the field variables is described. The procedure allows easy specification of boundary conditions. The feasibility of implementing the additional transport equations that are needed to describe thermal non-equilibrium, air chemistry, and plasma dynamics in AEROFLO are described. The experimental program also produced reduced kinetic models for the air chemistry, quantified the rapid energy thermalization phenomena, and measured the temperature rise due to repetitive nanosecond pulse discharge. The results of the experiments provide insight into the mechanism of flow control by nanosecond pulse, low-temperature plasma, as well as key nsec plasma actuator characterization and scaling data for validation of flow codes used for predictive modeling of high-speed flow control.