Numerical modeling of an RF plasma in argon

An axisymmetric, two-dimensional mathematical model of a radio frequency gas heater is described and compared with experimental data. The model includes mass, axial momentum, radial momentum, and energy conservation equations along with Maxwell's equation for the circumferential component of the electric potential vector. Buoyancy along the heater axis and radial jxb forces are included in the momentum equations. Ohmic heating and radiation losses are included in the energy equation. The radiation loss terms are divided into an optically thin component which leaves the gas directly and an optically thick component which is modeled as a conduction term. Results from the model agree reasonably well with data obtained from a laboratory scale gas heater using a bluff body to stabilize the plasma. Calculated results at increased mass flow and pressure are shown to indicate the models capability in designing larger scale heaters.