Torch plasma arcs have useful high-energy and high-current characteristics. Torch plasma arcs can be flexible even if exposed to high-speed laterally flowing gases. This study measured the length, voltage, input power, heat power and heat efficiency of a torch plasma arc to the anode to elucidate their influence upon the plasma torch arc anode attachment with a high-velocity laterally flowing gas. That velocity was varied from 0 to 60 m s −1 . The axial plasma gas argon flow rates used were 4, 8 and 12 slpm. Consequently, the input power increased about 8000-16 000 W with these lateral gas air velocities. The heat efficiency decreased with lateral gas air velocity from about 50% to 25% at a current of I = 150 A. The torch plasma arc length, L a , was ca 1 cm. The results of this study are applicable for providing electrical power from the ground to high-speed vehicles or vice versa and for reducing anode erosion by anode spot movement.

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SUMMARYThe torch plasma arc has useful characteristics of high energy and high current. The mode of torch plasma arcs can be flexible, even if the arc is exposed to the lateral gas. In this paper, we measured the input power, heat power, and heat efficiency of the torch plasma arc to the anode in order to determine the current effect on the anode attachment of plasma torch arc with high lateral air velocity, varying from 0 to 80 m/s at a plasma Ar flow rate of 12 slm. As a result, the input power increases with lateral gas velocity such as from about 8000 W to 16,000 W and the heat efficiency decreases with the lateral gas velocity such as from about 50% to 25% at the current I = 150 A and appearance plasma length L a = 1 cm. These results could be applied to providing the electrical power from the ground to high-speed mobiles, v.v., and to reducing an anode surface erosion by the anode spot movement.

Many of the wide range of parameters for which plasma torch have been developed are relevant for plasma diagnostics and these include operating current, electrode distance, plasma diameter, and axial plasma gas flow rate, inside the temperature and ambient pressure. Furthermore, its physical properties such as plasma power, Young's Modulus and voltage gradient become very im portant for the following reasons: the torch plasma is required to be bent; the torch plasma is considered using outside where wind blows; and the torch plasma is considered to he used as an energy transmitting medium between a flying object and the earth. C o p sequently, it is informed that the study on the properties is of fun damental importance. The torch plasma parameters were studied in detail by applying the high-speed crosswind. The transformation behaviors, plasma voltage, quantity of heat being received by cooling water inside the anode were examined. The plasma length stretched gradually as the crosswind velocity became higher. The higher the current of the torch plasma became, the higher the break velocity of the crosswind became. The higher plasma gas flow rate of the torch plasma made changing rate of the plasma voltage lower at higher crosswind velocity. When the crosswind velocity was under 37m/s, the plasma voltage did not have a difference so much for each plasma gas flow rate, but when it was over 37m/s, the plasma voltage increased dramatically and the higher plasma gas flow rate of the torch plasma had higher maximum plasma voltage. The increase of plasma power by crosswind velocity becomes milder with increasing current, and the substantial change in plasma power that is dependent upon crass-wind velocity is considered due t o the energy loss by cross-wind. Exposing the plasma to the cross-wind little by little, starting from no wind, initially the QonodE, the quantity of heat received by cooling water inside the anode, had a gentle decrease, but as the crosswind velocity increased over the critical value of V,,, crosswind speed, it shifted to a dramatic decrease. The rate of reduction of Qanok for the crosswind velocity becomes slightly lower, so that current becoma higher. The difference of Qsnod. for each plasma gas flow rate is smaller than Q. .for each current. The heat received by cooling water inside the anode under crosswind highly depends on current. And after the plasma voltage increases dramatically because of increase of crosswind, the changing rate of the heat received by cooling water inside the anode depends on plasma gas flow rate.