Numerical simulation of argon twin torch plasma arc for high heating efficiency

Plasma arc heating technology has been applied for volume reduction through melting of bottom and fly ash, and for producing slag. Recently, a twin torch plasma arc, which has two torches at the cathode and anode, has been anticipated for application to disposal of medical waste because it can treat a wide area and can treat non-conductive materials. For this study, a numerical simulation model of a twin torch plasma arc at opposite electrodes was developed to elucidate high-efficiency heating using a twin torch plasma arc. It is defined as Local Thermal Equilibrium (LTE) and calculated in Magneto-Hydro-Dynamic (MHD) equations. Furthermore, the temperature distribution and conditions of high heating efficiency with the radiation loss were addressed and compared to those of a single torch. The heating efficiency decreases with increasing radiation efficiency because of the temperature increment caused by the current and input power. The radiation efficiency of a twin torch is about 5% higher than that of single torch. (c) 2008 Elsevier Ltd. All rights reserved.