Effects of Thermal Conductivities on Heat and Mass Transferduring Directional Solidification
by
Victoria Timchenko
University of New South Wales, Sydney, Australia 2052
Coauthors: Mohammed El Ganaoui, Eddie Leonardi, Patrick Bontoux, Graham de Vahl Davis

Melting and solidification problems are very important in manufacturing processes such as crystal growth of semiconducters, and casting and welding of metals and alloys.

In this paper we investigate the effects of unequal thermal conductivity in the liquid and solid phase during directional solidification in both vertical and horizontal Bridgman configurations. Numerical solutions are obtained based using a fixed grid single domain (enthalpy) method using two different approaches - finite volume with primitive variables and finite differences vorticity-stream function formulation.

Two cases are investigated. The first one is that of a transient phase change problem of a pure substance with oscillatory and steady convection in the liquid region in the inverted Bridgman configuration (heated from below). The second case is the phas e change problem during transient directional solidification of binary alloy in the horizontal Bridgman configuration.

The significant effects of the variation of thermal conductivity on the interface shape and flow structures are discussed in detail.

http://reflab.mech.unsw.edu.au

Date received: February 22, 1999

Copyright © 1999 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # caco-13.