Numerical and experimental heat transfer analysis of two-phase flow through microchannel for development of heat dissipation correlation

Abstract

The current trend of reducing the size of electronic devices in the industry has extensively increased the demand for effective heat dissipation, thereby intensifying the need for high-performance heat-dissipating devices. A promising approach to solve this challenge is the use of single-phase (SP), two-phase (TP), and supercritical fluids in micro-channels (MCs). Two-phase cooling is applicable only to those devices in which the tip temperature is high enough to allow the cooling fluid to convert into a two-phase state. In all other cases, only single-phase cooling can be utilized. In this work, numerical and experimental investigations on MC have been performed using water as the working fluid to predict TP behavior and heat dissipation from electronic devices using SP and TP flow. A numerical model of flow boiling heat transfer was developed based on conservation equations, which is solved to identify the existence of single and two-phase regions in the MC and to study the variation of pressure along its length at different heating powers. Further, experiments were performed in both SP and TP conditions to observe the nature of flow regimes and the impact of various parameters on effective heat dissipation through MCs well as temperature distribution. Numerical results were validated with experimental results, which showed good agreement. Several experiments were also carried out to develop an empirical correlation between mass flow rate and heat power to maintain the electronic device temperature below 40 °C. The developed correlation is experimentally validated at three different heat powers 6 W, 8 W and 10 W.