Heat Transfer of Forced Convective Fin Flow with Cooling Applications to Electronic Chipset

Abstract

The detailed heat transfer measurements over three smooth-walled rectangular channels with open boundaries on their two side profiles and a sealed-bottom end, simulating a cooling passage in the fan-fin type heat sink of CPU cooling unit performed. The interactive effects of side-profile leakage flow and streamwise coolant stream are functionally related with Reynolds number and channel length-to-gap ratio, which demonstrate considerable influences on local and spatially averaged heat transfers over the fin surfaces Heat transfer modifications caused by varying Reynolds number (Re) and length-to-gap ratio of channel (L/B) over the ranges of 500≤Re≤3000 and 5.89≤L/B≤21.33 are disclosed by examining the detailed heat transfer distributions over the fin surfaces. In conformity with the experimentally revealed heat transfer physics, a regression-type analysis is performed to develop the correlation of spatially-averaged Nusselt number over fin surface, which permits the individual and interactive effect of Re and L/B on heat transfers to be evaluated. A criterion for selecting the optimal length-to-gap ratio of a confined fin channel that provides the maximum convective heat flux from fin surface is formulated.