Calculating the parameters of electric-arc heaters with gas-stabilized arcs

Computation of electric-arc parameters taking account of convective and radiant losses

“…Moreover, the stream of working gas entering the discharge channel usually possesses an initial noticeable turbulence, and hence the gas flow in real heaters may be turbulent. Belyanin [1] proposed a turbulent arc model for an approximate estimate of the basic heater parameters, and it received further development and extension in [2][3][4]. The turbulent model of a longitudinally cooled arc is based on the analogy between the development of an arc discharge in a gas stream and the propagation of a nonisothermal jet in a co-flow.…”

“…Within the scope of the turbulent model, the problem of the distribution of the stream and discharge parameters in a cylindrical channel has been solved approximately taking account of convective heat exchange between the gas and the wall [4]. A solution of this same problem is presented below, taking account of the radiant energy losses, for the case of an arc in an argon stream at atmospheric pressure.…”

“…A solution of this same problem is presented below, taking account of the radiant energy losses, for the case of an arc in an argon stream at atmospheric pressure. We shall not formulate the problem since it is described in detail in [4]. The change in the system of equations of the problem only concerns the energy equation in which the energy flux due to volume radiation of the plasma is introduced: R R i dV~-dx d (f 2~puhrdr) ~ 2~xqrrdr"…”

“…Integrating (1) and going over to dimensionless quantities, we obtain the energy equation in the following form (taking account of the simplifications introduced in [4]):…”

“…Using the equation for propagation of a turbulent nonisothermal jet in a co-flow [4] d~ _ = --0. l~ 2 Ah~ s , Here Q is a dimensionless criterion characterizing the intensity of volume radiation under the considered conditions, and q0, W/m~, is the characteristic magnitude of the specific energy flux due to the volume radiation. As we see, the fraction of the radiation in the energy balance of the arc is determined by the gas pressure and species (this is taken into account in terms of q0), and the gas discharge G, and depends quite strongly on the diameter of the discharge channel.…”