The flow, temperature and concentration fields in a radio-frequency argon-helium plasma

The numerical simulation of an RF argon-helium thermal plasma under atmospheric pressure was performed. The two-dimensional continuity, momentum, energy and species equations along with the electromagnetic equations were solved simultaneously with the SIMPLER algorithm. The physical properties of the argon-helium mixed plasma were taken into account. The plasma velocity, temperature and concentration were measured with a water-cooled probe. The numerical results were in good agreement with the experimental ones. The results demonstrate the existence of an inward radial flow induced by the electromagnetic pumping effect. The recirculating eddy formed by the inward radial flow becomes stronger in an argon-helium plasma than that in an argon plasma. A uniform distribution of helium concentration is obtained upstream from the discharge region.