AN IMPLICIT/EXPLICIT NUMERICAL METHOD FOR PHASE-CHANGE HEAT TRANSFER BASED ON POROUS MEDIA FORMULATION

Abstract

© 2025, Begell House Inc.. All rights reserved.This paper presents a novel numerical approach for addressing the phase change term in the energy equation. The One-Energy Equation Model (1EEM) is extended to handle both melting and solidification processes for pure substances and alloys. Prior to melting and after solidification, the solid material is modeled as a porous medium with low porosity and minimal permeability. During phase transition, thermal equilibrium is assumed in the mushy zone. As the temperature surpasses the melting point, viscous and form drags in the momentum equation decrease. Latent heat is discretized using a combination of implicit and explicit methods in the energy equation. After computing the temperature field, the liquid fraction is updated across the domain. The algebraic systems are solved using the SIMPLE algorithm, with inner iterations utilizing the Strong Implicit Procedure. Initial findings show that the model produces results consistent with those found in the literature.

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