Numerical Simulation of Unidirectional Unsteady Solidification under Variable Gravity Conditions

Abstract

A numerical simulation code of the unsteady convection-solidification combined process was developed to study solidification processes under microgravity. Boundary fixing method was applied for the method to get a solution. Time evolutions of solid-liquid interface, isotherms, and flow patterns of unidirectional solidification of succinonitrile were calculated for several gravity vectors and boundary conditions to obtain the informations about the following cases: (1) solidification when changing gravity vector, (2) solidification for endothermic boundary condition and (3) solidification when changing gravity level. It was demonstrated that the interfacial patterns varied with time, boundary condition, gravity direction and gravity levels. It was found that the numerical results well explained experimental ones for both interfacial patterns and average solidification rates.