MODELING OF THE CATHODE JET OF A HIGH-POWER TRANSFERRED ARC

A physical model of two zones (constricted arc and cathode jet) of a 1 -MW transferred arc in air is presented. It is based on the solution o f conservation equations by a finite-difference method. Turbulence is treated with Prandtl's approximation, whereas radiative transfer is so lved considering a nonhomogeneous medium, with the hypothesis of gray spectral bands. The influence of radiative transfer on the temperature field is illustrated using two-band and four-band radiation models. W e also show the influence of several parameters on plasma jet properti es: current intensity between 500 and 1500 A; gas mass flow rate betwe en 10 and 90 g/s; vortex injection. The arc characteristics are analyz ed in accordance with physical mechanisms such as heat conduction, rad iation, turbulence, convection, and mixing of cold gas.