STEP MODEL OF EROSION OF ELECTRODES. I. APPLICATION TO ARC SPOTS ON THE CATHODES OF ELECTRIC-ARC HEATERS
A. Marotta,a L. I. Sharakhovskii,b, and A. M. Esipchukb UDC 621.387.143.014.31 A simple model of erosion of cold electrodes which considers the step motion of arc spots is proposed. It is assumed that the macroscopic destruction of an electrode begins with fusion of the electrode in the spot. The basic thermal characteristics of the arc spot, the thermophysical properties of the electrode material, and the regime of the electric arc are taken into account. The notion of the effective erosion enthalpy which summarizes all the elementary processes leading to the erosion of the electrode is used. The model has successfully been applied to arc spots on the cathodes of electric-arc heaters. A comparison with the earlier model of continuous motion of the spot has been made. aGleb Wataghin Institute of Physics at Campinas State University, Campinas, Brazil (Instituto de Fisica "Gleb Wataghin," Universidade Estadual de Campinas, Campinas, Sã Paulo, Brasil); email: aruy@ifi.unicamp.br. bA. V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus, Minsk, Belarus; email: leonids@land.ru; Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 76, No. 2, pp. 116-122, March-April, 2003. Original article submitted October 14, 2002