Numerical modeling of plasma cutting torches.

Abstract

In this thesis, a study of numerical modeling technique is performed for various plasma cutting torches. The plasma cutting process model uses a finite volume method based on the SIMPLEC algorithm along with the solver “FAST-2D (Flow Analysis Simulation Tool-2D).” The source code available is a general code and does not include any finite volume grid generator. Part of this work includes development of a generalized finite volume grid generator dedicated for the new generation plasma torches. This modified version of the grid generator offers users a great flexibility in grid and geometry choice, and offers the advantage of easy variations in boundary conditions. The work presented also includes a detailed study of the effect of the radiation model and the cathode current density boundary condition on the distribution of the plasma field quantities. Finally the modified version of the grid generator along with the appropriate radiation model and current density boundary condition at the cathode are employed to simulate selected plasma cutting torches from Hypertherm Inc.