This paper describes numerical magnetohydrodynamic (MHD) calculation of heat plasma used in heating and welding processes. Most of the calculation models have been two dimensional and static. Since physical phenomena are three dimensional and nonstatic, three dimensional, dynamic MHD calculation of heat plasma is developed in this paper. Since local heat balance is assumed, the heat plasma is considered as a conductive fluid dynamic material such as molten metal. However, heat plasma's material constants such as density, heat transfer coefficient, specific heat, and electrical conductivity are strong functions of the temperature. Temperature is governed by heat plasma material transfer and heat transfer. Material transfer is driven by the electromagnetic force. Turbulent flow is modeled by the large eddy simulator including heat transfer. The electrical phenomenon is modeled using the Poisson equation in a dc magnetic field. It is assumed that the static electrical force may be ignored. Calculations show that the heat plasma concentrates at the center. The center area is of low density and high electrical conductivity. To verify the usefulness of this 3D dynamic MHD method, a conventional model, which is 2D and static is compared to a k-ε model. Comparison of velocity distributions shows good agreement.
ASJC Scopus subject areas
- Physics and Astronomy(all)