Hybrid stabilized electric arc: numerical study of the performance under different radiation models

Summary form only given. The aim of this paper is to study the influence of different radiation models on the radial energy transfer from the hybrid arc and overall arc performance for different currents and molar ratios argon-water. We employ three radiation models in our calculation: The two models involve the net emission coefficients approach, and one of them accounts for the reabsorption of radiation at the colder arc boundary. In the third model, radiation transfer within the arc column is calculated using the partial characteristics method for atmospheric pressure water-argon arc discharge. Results carried out for 150-600 A and for argon mass flow rates 7.5-27.5 slpm proved that hybrid stabilized electric arc exhibits higher outlet velocities under the practically unchanged plasma enthalpy compared to Gerdien arc. Reabsorption of radiation implies higher outlet temperatures and velocities with respect the case for zero reabsorption. The amount of reabsorbed radiation in the method of partial characteristics is decreased since the molecules of water species have been neglected in calculation so far. Comparison between present calculation and experiments carried out on the hybrid plasma torch operating at the institute shows a good agreement.