Abstract:
In the aerospace field, the arc plasma technology is essential in the high temperature gas dynamics test. In this paper, the overall thermal characteristics of the axial arc plasma torch with self-sustaining arc length and double arc chambers are studied experimentally for different parameters. The characteristics including the heat efficiency, the enthalpy and the average temperature of the jet-flow, as well as the jet length are obtained, and the results are analyzed based on the heat transfer among the arc, the gas flow and the electrodes. It is shown that for a power between 104 kW and 300 kW, the heat efficiency of the plasma torch is positively correlated with the power in a range of 49.1% to 70.8%, the maximum values of the enthalpy and the average temperature of the plasma jet-flow achieved at a power of 152 kW, are 10.29 MJ/kg and 5006 K, respectively. When the power keeps constant, the heat efficiency is better with a combination of lower arc current and higher load voltage, but the enthalpy and the average temperature of the jet-flow will be lower correspondingly. When the gas flow rate keeps constant, the heat efficiency of the torch decreases with the increase of the arc current, while the enthalpy and the average temperature of the jet will rise in consequence.