Numerical Analysis of the Rapid Solidification Process of NiTi Binary Alloy

Abstract

The objective of the present work is to analyse the solidication process of NiTi binary alloy. The physical medium is taken as an incompressible uid where the heat is transferred by conduction and convection, including the thermal phase change phenomenon. The last one is modelled by the improvement procedure called enthalpyporosity formulation, where the liquidsolid mushy zone is treated as a porous zone with porosity equal to the liquid fraction. The numerical model is based on the nite volume method in body tted coordinates with a SIMPLER scheme to couple the pressure and velocity elds. The results are presented for the velocity and temperature eld, as well as for the NiTi mass fraction during the solidication process.

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