A MICRO-MACRO MODEL FOR NUMERICAL SIMULATION OF DENDRITIC ALLOY SOLIDIFICATION

摘要

The present article reports on a micro-macroscopic modeling approach for dendritic columnar alloy solidification systems. The computational convenience of the continuum model in using standard single-domain CFD procedure has been retained by using a fixed-grid dual-scale numerical approach. The local solidification rate is calculated by implicit iterations of macroscopic conservation equations and the microscopic solute redistribution model. Simulation results for solidification in the presence of thermo-solutal convection are presented with emphasis on the influences of micro-structural parameters that affect the permeability and microscopic solute distribution on the predicted convection and macrosegregation patterns.