Experimental and numerical investigations on natural convective cooling of electronic equipments using dual coolants

Abstract

Experimental and numerical analysis on electronic equipment cooling with use of multiple coolants viz., ethanol, gasoline, mixture of ethanol and gasoline, acetone under natural convection mode have been explored in the present thesis. The principle involves the use of more than one fluids to achieve the objective. The heat removal has been attempted by using dual tanks viz., primary and secondary tank in which the primary and secondary coolants are filled respectively. The electronic component is thermally guided by a primary coolant water by non-contact cooling, while a secondary coolant assists to remove the heat from the primary coolant. The primary and secondary coolants remain unmixed. The heat from the secondary coolant is eventually dissipated to the ambient air.Heat carried away by primary, secondary coolants and convective heat transfer co-efficients have been estimated by using energy balance method. The experimental result shows that maximum convective heat transfer co-efficient has been achieved as 430W/m2-K for heat input of 60W and primary (water) and secondary (ethanol) coolant combinations due to a high figure of merit(FN) which enhance heat transfer rate in the higher side. Nusselt number for both primary and secondary coolant have been estimated. Correlations have been developed in terms of Grashof number and Prandtl number. The novelty in the secondary coolant correlation is an inclusion of blending ratios (and#966;1 and and#966;2) along with the Rayleigh number. 71.4% of total 42 data, has been found to be within ± 30% of error range. newline