Lattice Boltzmann simulation of natural convection heat transfer phenomenon for thermal management of multiple electronic components

Abstract

Thermal management of electronic components is becoming a vital necessity in view of the rapid development of electronics technology. It is a concern imposed by the miniaturization of electronic chipsets. The present work addresses this issue numerically, using the lattice Boltzmann method (LBM). It consists of an air-filled heat sink containing multiple protruding electronic components. The problem is modelled using 2D continuity, momentum, and energy conservation equations. The thermal and dynamic fluid flow are analysed for various enclosure inclinations (0°, 45°, and 90°) and Rayleigh numbers (Ra=103-106). A twin protruding heat sources are considered at the bottom wall. The top cold wall can be at a uniform temperature (case 1) or consisting of two protruding sinks maintained at a constant temperature (case 2). The results showed that the maximum heat transfer rate corresponding to Nusselt number (Nu¯=5.51) is achieved for Ra=106 on the hot wall for the horizontal cavity in case 1, illustrating the cavity with top cold uniform wall. Indeed, the heat transfer is improved by 80% by varying the Rayleigh number (Ra) from 103 to 106. Furthermore, for case 2 with a twin cold protruding, a quite complicated heat transfer behaviour is observed on the hot wall. For Ra>106, the horizontal cavity outperforms the other cavities in terms of heat transfer rate, however the horizontal position is the less performant for Ra<104. With a horizontal disposition and Ra=106, the heat exchange ratio is improved by 32.32% in case 2 compared to case 1. The outcomes of this study provide insights into design and implementation of natural convection cooling solutions for electronic devices, which can have significant practical implications in various industries.