Comparative study of turbulence models for SF_6 arcs in a supersonic nozzle

摘要

A comparative study of the two most popular turbulence models, the Prandtl mixing length model and the K-epsilon model, has been carried out for turbulent SF_6 arcs burning in a supersonic nozzle under direct current conditions. The computed radial temperature profiles are compared with those measured previously by Leseberg and Pietsch at currents of 100 A, 600 A and 1800 A, respectively. It has been found that the turbulence parameters of the K-epsilon model are dependent upon the arcing current while those of the Prandtl mixing length model are applicable for all the currents investigated. For turbulent SF_6 arcs in a supersonic nozzle, consideration of the range of applicability of the turbulence parameters and the cost of computation have made the Prandtl mixing length model preferable to the K-epsilon model.