Constructal design for convection melting of a phase change body

S. Ziaei (1) , Sylvie Lorente (2) , A. Bejan (1)

1 Department of Mechanical Engineering and Materials Science
2 LMDC - Laboratoire Matériaux et Durabilité des constructions

This paper documents a numerical study of time-dependent melting dominated by natural convection in a cylinder filled with a phase change material. In accord with constructal design, the search is for effective heat-flow architectures. The volume-constrained improvement of the designs for heat flow begins with assuming the simplest structure, where a single line serves as heat source. Next, the heat source is endowed with freedom to change its shape as it grows. The objective of the numerical simulations is to discover the geometric features that lead to the fastest melting process. The results show that the heat transfer rate density increases as the complexity and number of degrees of freedom of the structure are increased. Furthermore, the angles between heat invasion lines have a minor effect on the global performance compared to other degrees of freedom: number of branching levels, stem length, and branch lengths. The effect of natural convection in the melt zone is documented. (C) 2016 Elsevier Ltd. All rights reserved.

Mots clés: Evolutionary design; Dendritic; Energy storage; Constructal; exchangers; Melting; microchannel heat sinks; Natural convection; Phase change material; pipes; optimization; temperature; thermal-energy storage; Tree shaped

Domaines: Génie civil

S. Ziaei, Sylvie Lorente, A. Bejan. Constructal design for convection melting of a phase change body. International Journal of Heat and Mass Transfer, 2016, 99, pp.762--769. ⟨10.1016/j.ijheatmasstransfer.2016.04.022⟩. ⟨hal-01849708⟩