Presented in
AFS Transactions '95
Page 243
Thermal Transport Phenomena in Metalcasting Simulations
H.
Huang
O. Gurdogan
H.U. Akay
Technalysis Incorporated
Indianapolis, Indiana
W.W.
Fincher
Lufkin Industries, Inc.
Lufkin, Texas
Abstract
An interface element model
has been developed for a finite element method-based casting
filling/solidification simulation software. The thermal resistance at the
casting-mold interface is treated through an interface element with zero
thickness and coincident nodes. The principle of this model is described.
The model is tested through an example of practical size. The computed
results of the interface element model are compared with the experimental
data, as well as the computed results of the conventional effective heat
transfer coefficient model and common node model.
A heat source/sink algorithm
has also been incorporated into the solidification solver. The algorithm
combines the concept of the temperature recovery method and heat source/sink
term in the thermal energy equation. The advantage of this algorithm, over
the effective specific heat method, is that the phase transformation will
not be complete until all the heat of transformation has been released or
absorbed.
Introduction
Heat transfer across
the casting-mold interface plays an important role in the heat removal from
the molten metal and, hence, the filling and solidification of a casting. It
has been recognized that a fast rate of heat removal from the molten metal
helps to obtain better microstructures and reduce undesirable pores in a
casting. On the other hand, a slow rate of heat removal may result in coarse
microstructures and allow undesirable pores to develop. Generally speaking,
most thermal energy in molten metal is removed through the casting-mold
interface. Hence, the heat transfer across the casting-mold interface has
received considerable attention from metalcasting researchers.