Numerical Study of Free Convection Dominated Melting in an Isolated Cavity Heated by Three Protruding Electronic Components

This paper presents the results of a numerical study of the melting and natural convection in a rectangular enclosure heated with three discrete protruding electronic components (heat sources) mounted on a conducting vertical plate. The heat sources generate heat at a constant and uniform volumetric rate. A part of the power generated in the heat sources is dissipated in phase change material (PCM,
n
-eicosane with melting temperature,
Tm
= 36°C) that filled the enclosure. The advantage of using this cooling strategy is that the PCMs are able to absorb a high amount of heat generated by electronic components without activating the fan. To investigate the thermal behavior of the proposed cooling system, a mathematical model, based on the mass, momentum, and energy conservation equations, was developed. The governing equations are next discretized using a finite volume method in a staggered mesh, and a pressure correction equation method is employed for the pressure-velocity coupling. The energy conservation equation for the PCM is solved using the enthalpy method. The solid regions (substrate and heat sources) are treated as fluid regions with infinite viscosity. A parametric study was conducted in order to optimize the thermal performance of the heat sink. The optimization involves determination of the key parameter values that maximize the time required by the electronic component to reach the critical temperature (T < T
_cr
).