Effects of radiation on enhanced electronic cooling

The radiation component of heat transfer has been shown to provide a significant portion of the power dissipation capability for certain applications of enhanced surfaces in electronic cooling. Experimental work using two surface coatings has shown that the radiation interchange can be increased in natural-convection cooled environments for both horizontally and vertically oriented heat sinks. It was also shown that, to a lesser degree, the radiation component of heat transfer is effective in a forced convection environment. Based on experimental data from an oxidized aluminium heat sink, the radiation component was evaluated using the geometry constraints of a heat sink enclosed within a system environment consisting of gray reradiation walls. The equations used were then modified to simulate a change in heat-sink surface finish. The results of this investigation indicate that, for an aluminium heat sink, in the test configuration evaluated, the radiation component in a natural convection environment dissipated approximately 5% of the total heat flow.<>