Flow and Temperature Fields in a Free Discharge Inductively Coupled Plasma

摘要

Computations were made of the flow and temperature fields in an inductively coupled argon plasma at atmospheric pressure under confined and free discharge conditions. The model takes into account gravity effects and swirl in the sheath gas. Natural convection was found to have a negligible effect on the flow and temperature fields under confined discharge conditions but a significant effect for the free discharge. The back flow in the discharge was substantially reduced in the presence of swirl for swirl velocities over the range 0-50 m/s. Also with a mode-rate increase in swirl, the conduction heat flux to the wall decreased but increased with the further increase in swirl. From an overall energy balance point of view, conductive heat flux to the wall of the plasma confinement tube was substantially lower for a free plasma discharge compared to that for a confined plasma. (ERA citation 09:038920)