Melting of a phase change material in concentric horizontal annuli of arbitrary cross-section

Results are presented of a finite element computational study of the free c onvection-dominated melting of a pure phase change material contained in co ncentric horizontal annuli of the following configurations: (a) square exte rnal tube with a. circular tube inside - annulus type A and (b) circular ex ternal tube with a square tube inside - annulus type B. Effects of the Rayl eigh number as well as heating of the inside, outside or both walls at a te mperature above the melting point of the material were studied. Flow and te mperature patterns within the melt, local heat flux distributions at the he ating surface and the cumulative energy charged as a function of time are p resented and discussed. (C) 2000 Elsevier Science Ltd. All rights reserved.