A Downhill Simplex Method for Computation of Interfacial Heat Transfer Coefficients in Alloy Casting

Abstract

This article describes methods used for obtaining both the thermal contact resistance (TCR) between an alloy casting and the mold, and the heat transfer coefficient (HTC) between the mold and a bath that is used to control the speed of the solidification process. Both the Downhill Simplex optimization method and Beck's approach are used in the inverse task. These inverse tasks, which simultaneously compute both the TCR and HTC, use a model involving a phase change during the solidification of the alloy. An automatically generated mesh uses the control volume method and ''Direct Enthalpy'' algorithm [1] instead of the ''Total Enthalpy'' approach [2] to compute the temperature profile inside the alloy-casting model. A comparison of the Downhill Simplex optimization method and Beck's approach is made.

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