The average speed of the anode arc attachment and plasma flow in a hybrid DC arc plasma torch is measured under different experimental conditions and curves that fit the measured values are generalized. A high-speed camera, and photodiodes are utilized.
It is found that the average attachment speed and consequently the plasma flow speed can be expressed as one function of ambient pressure, arc current, argon flow rate, exit nozzle diameter, and distance between the exit nozzle and anode.