3-DIMENSIONAL MODELING OF UNSTEADY HIGH-PRESSURE ARCS IN ARGON

Three-dimensional, unsteady behaviour of high-pressure electric arcs i n argon is studied by means of numerical simulations. Attention is pai d to argon arcs whose steady structure is fairly well understood. Resu lts are reported for the case of a one centimetre long are, burning in argon and driven by a total current of 200 A and 300 A. The influence of the boundary conditions for the electrical potential on the macros copic structure of the are is studied and it is found that the distrib ution of the current density near the cathode is one of the critical p arameters which can significantly modify both the distribution of mean quantities and the stability of the are. All mean quantities found fr om three-dimensional calculations are compared with two-dimensional ax i-symmetric fields obtained by a previously used code for are simulati ons. The results indicate good agreement between the results from thre e-dimensional calculations, hive-dimensional axi-symmetric simulations and results from physical experiments documented in literature.