Computational modeling of turbulent melt flow in CdZnTe crystal growth

Abstract

A computational model of CdZnTe crystal growth including turbulent phenomena in the melt is presented as a continuation of the previous work by Černý, Kalbáč and Přikryl [Comp. Mater. Sci. 17 (2000) 34]. The ternary CdZnTe system is treated as pseudobinary in the temperature range under consideration. The phase interface between the solid and liquid is modeled as a discontinuity surface. The k– ε model for low turbulent Reynolds numbers is used for the description of the turbulent processes. The numerical solution of the model is done using the Galerkin finite element method in two-dimensional approximation with cylindrical symmetry. The problem of moving boundary is solved by a front-fixing method. The results obtained with the turbulent model are compared to those of the previous laminar model and the influence of including the turbulence into the model is discussed. It is shown that the laminar and the turbulent models exhibit significant differences in the structure of melt flow, concentration profiles, and also in the movement of the phase interface for larger time periods.