Modeling the interaction of convex solidifying interfaces with spherical particles

ELIANA M. AGALIOTIS; MARIO R. ROSENBERGER; ALICIA E. ARES; CARLOS E. SCHVEZOV

Beijing, China

Congreso; The 16th International Conference on Crystal Growth(ICCG-16)in conjunction with The 14th International Conference on Vapor Growth and Epitaxy(ICVGE-14) will be held together; 2010

Chinese Association for Crystal Growth

In the present report, the phenomenon of pushing is modeled for the case of particles generatinga convex interface is considered. The thermal and fluid field calculations are made in adecoupled way determining first the shape of the interface, and then the two main forces actingduring pushing; the drag and repulsion forces. The thermal and fluid flow fields werecalculated using finite element methods.Both, the drag and repulsion forces are integrated at each step and compared until both areequal and the steady state of pushing is reached. The pushing force is integrated using theCasimir-Lifshitz-Van der Waals interaction.It was found that the model predicts the equilibrium distance in a steady state of pushing forspherical particles and a convex solidifying interface. It is shown that the separationequilibrium distance for a convex interface with respect to an ideal planar interface results in alarger solidification velocity for trapping. The model results were in good agreement withexperimental results for the critical velocity reported in the literature.