Simulation study of a capacitive-coupled plasma torch array

Summary form only given. Dense atmospheric-pressure plasma can be produced through a low frequency discharge operating in the high current diffused arc mode, such as a plasma torch, which introduces a gas flow to carry plasma out of the discharge region. However, the volume of a single torch is, generally, not large enough for most of the applications. A simple way to enlarge the plasma volume is by introducing an array of torches as a plasma source. To keep the size of the source compact, torches in the array have to be coupled to each other so that the number of power sources operating the array can be reduced considerably. Using capacitive-coupled electrical discharges, a single 60 Hz source lights up an array of three plasma torches simultaneously. The discharge voltage and current of each torch is measured for three cases of one to three torches being lit up in the array. The results determine the V-I characteristic of the discharge, which indicates that the torch is operating in a diffuse arc mode. An equivalent circuit based on the V-I characteristic is developed to model and simulate the operation of the torch array. The simulation results of the discharge voltage and current of a torch validate the circuit model by showing excellent agreement with those from the experimental measurements for the three cases . This lump circuit model is then used to carry out numerical simulations of the discharge for a broad parameter space of plasma species. By fitting the simulation results, a function giving the parametric dependence of the consumed average power density