Model and simulation of a capacitively coupled plasma torch array

Using capacitively coupled electrical discharges, an array of plasma torches powered by a single 60 Hz source are lit up simultaneously to produce a sizable dense plasma in the open air. The number of torches in the set is limited by the power handling capability of the source. The discharge voltage and current of each torch is measured for three cases of one to three torches in the array. The results determine the u-icharacteristic of the discharge which indicates that the torch is operating in a diffuse arc mode. The torch array is modeled by an equivalent circuit for simulating its operating. The simulation results of the discharge voltage and current of a torch are shown to agree well with those from the experimental measurements for the three cases. The lump circuit model is then used to carry out numerical simulations of the discharge for a broad parameter space of plasma species. An empirical dependence of the power consumption on average electron density maintained in the plasma is obtained to be (P) = 6.1 x 10^-21(n_e)^1.9 α^0.4, where a is the electron-ion recombination coefficient used as a variable parameter in the simulation.