A. Bejan et Ga. Ledezma, THERMODYNAMIC OPTIMIZATION OF COOLING TECHNIQUES FOR ELECTRONIC PACKAGES, International journal of heat and mass transfer, 39(6), 1996, pp. 1213-1221
This paper describes several fundamental trade offs that govern the op
timization of cooling techniques for heal generating electric devices.
Five basic cooling configurations are optimized. It is shown that in
forced air cooling above room temperature the fan power requirement is
minimum when the heat transfer contact area is optimized to a value t
hat is of the order of 10(2) A(f), where A(f) is the flow cross-sectio
nal area. This optimal contact area is independent of whether the cool
ant is mixed or unmixed inside the heat generating enclosure. In air c
ooling with natural updraft, the heat generation rate (or amount of el
ectronics, or overall thermal conductance) is maximum when the heat tr
ansfer contact area is of order 10(2) A(f). In forced convection cooli
ng at cryogenic temperatures, the refrigerator power requirement has m
inima with respect to the cold-end (refrigeration load) temperature an
d the heat transfer contact area. The optimal heat transfer area is ag
ain of the order of 10(2) A(f).