Column of an atmospheric-pressure electric arc

An analytic method is proposed for calculating the electrical and thermal characteristics of a cylindrical arc with a plasma whose conductivity depends exponentially on the temperature. The energy equation in the inner current carrying region is solved by expanding the exponent. This solution is matched with the outer solution at the radius where the densities of input electrical power and loss by heat conduction to the walls are approximately equal. The calculated current–voltage characteristics and temperature distributions for different molecular gases are compared with corresponding experimental data and with an exact numerical solution. The conditions for applicability of this method are discussed.