Volt-Ampere and Thermal Features of a Direct-Current Dual-Jet Plasma Generator With a Cold Gas Injection

Experimental studies on the volt-ampere characteristics and thermal efficiencies of a dual-jet direct-current arc thermal plasma generator with a cold gas injection are conducted. Discharge image processing results using the contour extraction method with the variable binary thresholding technique show that, compared with the conventional dual-jet plasma generator, the length of the high-gas-temperature region increases, the arcjet expands downward with the injection of cold gas, and the arc voltage and the thermal efficiency both increase by increasing the flow rate of the injected cold gas as a whole, accompanied by the more severe electrode ablation. The derived generalized dimensional complex equations concerning the electrical and thermal characteristics of the plasma generator based on the measured data and using the multiple linear regression method can, to some extent, be employed to predict the electrical and thermal features of the plasma generator. These equations are helpful for the design and operation of the dual-jet thermal plasma generator with a cold gas injection in actual applications.