An enthalpy-porosity method is extended to the simulation of crystal growth process via directional solidification. The approach is based on a homogeneous formulation for Navier Stokes and energy equations and involving a two-phases intermediate zone modelled as a porous medium. A finite volume approximation is used with a fixed mesh. The front capturing technique is validated with respect to an interface tracking method. The applications concern the interaction of steady and oscillatory melts with the interface during Bridgman crystal growth. The effect of an axial magnetic field is considered in steady case. The amplification of oscillatory instability in the melt is studied in the case of inverted Bridgman configuration (heated from below). Various solutions (steady symmetric and asymmetric, time-periodic, aperiodic...) are analyzed. Successive interfaces are considered over a characteristic growth time scale in order to exhibit some typical crystal constitution.
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