An analytical solution for the close-contact melting with vertical convection and solid-liquid density difference

- Journal title : Transactions of the Korean Society of Mechanical Engineers B
- Volume 21, Issue 9, 1997, pp.1165-1173
- Publisher : The Korean Society of Mechanical Engineers
- DOI : 10.22634/KSME-B.1997.21.9.1165

Title & Authors

An analytical solution for the close-contact melting with vertical convection and solid-liquid density difference

Yu, Ho-Seon; Hong, Hui-Gi; Kim, Chan-Jung;

Yu, Ho-Seon; Hong, Hui-Gi; Kim, Chan-Jung;

Abstract

The steady state close-contact melting phenomenon occurring between a phase change material and an isothermally heated flat plate with relative motion is investigated analytically, in which the effects of vertical convection in the liquid film and solid-liquid density difference are incorporated simultaneously. Not only the scale analysis is conducted to estimate a priori qualitative dependence of system variables on characteristic parameters, but also an analytical solution to a set of simplified model equations is obtained to specify the effects under consideration. These two results are consistent with each other, in that the vertical convection affects both the solid descending velocity and the film thickness, and that the density difference alters only the solid descending velocity. While the effect of vertical convection can be characterized conveniently by a newly introduced temperature gradient factor which asymptotically approaches the unity/zero with decreasing/increasing the Stefan number, that of density difference is represented by the liquid-to-solid density ratio. It is shown that the solid descending velocity depends linearly on the density ratio, and that the ratios of solid descending velocity, film thickness and friction coefficient to the conduction solution are proportional to 3/4, 1/4 and -1/4 powers of the temperature gradient factor, respectively. Also, established is the fact that the effect of convection can be legitimately neglected in the analysis for the range of the Stefan number less than 0.1.

Keywords

Close-Contact Melting;Vertical Convection;Solid-Liquid Density Difference;

Language

Korean

Cited by

2.

분할된 핀붙이 전열면상에서의 얼음의 용융,홍희기;김무근;

설비공학논문집, 2000. vol.12. 1, pp.67-74

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