The analysis of phase-change heat transfer is of importance of phase change
in many physical situations, but such analyses are difficult because of th
e nonlinear governing equations. The extensive use of numerical methods to
analyze heat transfer problems has great potential but also some pitfalls.
This article analyzes the advantages and disadvantages of the enthalpy meth
od and several interface-following methods for modeling solid-liquid phase-
change problems using the finite-difference method. Since the initiation of
melting always numerical difficulties, this article also analyzes the effe
ct of the initial melt region size. Finally, the use of first-order finite-
difference models for the moving-interface term in the interface-following
method is shown to be inaccurate for high heat transfer rates. A second-ord
er-accurate method is presented that gives accurate results in all situatio
ns.