Studies of electric arc сombustion in the swirling flow of a cylindrical discharge chamber of a plasma torch at oxygen consumption of 10-160 g/s are carried out. It is established that the electric field strength is constant along the channel at the initial section of the arc, and the length of this section is determined. On the basis of the similarity theory in a wide range of changes in the parameters of the plasma torch, methods for determining the electric field strength of the arc and the length of the initial section are obtained. The length of the plasma torch is calculated, which mainly includes the length of the initial section, where the voltage is constant, and the current-voltage characteristics. The design of the plasma torch was created. Theoretical studies of near-electrode processes at the cathode and anode were carried out, on the basis of which electrode materials were selected and cathode and anode structures were created that provide high thermal efficiency and service life of the plasma torch. The developed plasma torch can be used as a highly efficient arc source of ultraviolet radiation for generating ozone, for heating oxygen, as well as in metallurgy, chemical industry, for example, the production of titanium dioxide and ozonation.