Numerical investigation of thermochemical nonequilibrium flow field in a 20kW arc heater coupled with electric field calculation

Numerical simulation is carried out and the distribution of flow field properties is obtained for nonequilibrium flow in a constrictor-type 20kW arc-heated wind tunnel. In the arc heater, plasma flow is highly in nonequilibrium and arc discharge plays a critical role. The flow field is described by the Navier-Stokes equations with a multi-temperature model. The flow field equations are solved with the governing equation for the electric field being coupled. Furthermore, to validate the present numerical model, the numerical solutions are compared with the corresponding experimental data. The flow characteristics in the 20kW arc heater, e.g., the arc charge and the supersonic expansion, become clear through the present simulation. Moreover, the computed results for the arc heater indicate almost full dissociation/ ionization reactions and thermochemical equilibrium in the constrictor part, while strong nonequilibrium clearly appears in the nozzle section.