Study on forced air convection cooling for electronic assemblies

In the present work, the slotted fin concept was employed to improve the air cooling performance for heat sinks of plate-fin type. Numerical simulations of laminar heat transfer and flow pressured drop were conducted for the integral plate fin, discrete plate fin, and discrete slotted fin heat sinks. It is found that the performance of the discrete plate fin is better than that of integral plate fin and the performance of slotted fin is better than that of discrete plate fin based on the same pumping power of the fan. Then a type of heat sink was proposed, which is characterized by discrete and slotted fin surface with thinner fin height and shorter fin spacing. Preliminary computation shows that this type of heat sink may be useful for the next generation of CPU of higher thermal load with an efficient fan. The issue of the limit of air-cooling techniques was also analysed.