An alternative two-phase formulation and analytical solution for a Stefan problem in one-dimension accounting for volume change and sensible heat

Abstract

Stefan problems, or free boundary problems, in the phase change process occur in many engineering problems. This paper develops a compact formula for a two-phase melting process in a one-dimensional semi-infinite slab with a novel approach. Unlike the classic Stefan problem, the novel approach considers volume change (or density difference) and the net-sensible-heat of the two phases. Furthermore, an analytical solution is proposed. To illustrate, the melting process of ice-water in a pipe is investigated. The results have been validated through an exact solution and comparisons with other relevant models. A special case of a one-phase problem is also proposed. The proposed model can be used as an alternative tool for engineers in estimating the position of the melt-front, depending on the dominant effect on the phase change process.

Keywords

• Stefan problem
• Volume change
• Density difference
• Melting process
• Moving boundary problem
• Phase change