Enhanced cooling of electronic components by flow oscillation

Abstract

An experimental investigation was conducted to examine the effect of forced oscillation of the fluid (air) entering an electronic circuit pack channel on component cooling. A realistic air-cooled channel made of two vertically mounted circuit packs containing nine components each was setup. Each component was individually powered and its temperature monitored. To induce controlled oscillation of the incoming air, a low-aspect ratio blade attached to a mechanical shaker was placed at the inlet of the channel. Several parameters including component power dissipation, air velocity (natural to moderate forced convection ReD = 3000), blade angle, and channel width were varied. The component-flow exposure was enhanced by setting the blade frequency to the frequency of the free-shear layer present in the groove formed by the components. This resulted in significant cooling of the components. The results showed that for blade frequencies varying from 1 to 3 Hz up to 25% cooling can be attained in electronic components.