Interfacial Heat Transfer Coefficient in Unidirectional Permanent Mold Casting: Modeling and Inverse Estimation

Abstract

The thermal control of the permanent mold casting process is highly dependent on the Interfacial Heat Transfer Coefficient (IHTC). Based on that, many works proposed several models in order to estimate its behavior. This work intends to study three IHTC models present in the literature, as well as to propose and analyse two new models. The proposed models are based on two distinct methodologies: thermal resistance method and analytical comparison to the thermal gradient formulation at the metal/mold interface. All these models will be analysed in terms of their ability to reduce the error between the simulated and experimental thermal profiles by using an inverse method and verifying their respective parameter sensitivity based on the relative sensitivity coefficient. It is observed that the exponential formulation model, proposed in this paper, is able to reduce the numerical/experimental error more efficiently than the others methods in all three hypoeutectic alloys of the Al-Si system considered.