Analysis of micro-channel heat sinks with rectangular-shaped flow obstructions

It is recognized that cooling methods incorporating micro-channel heat sinks with high capacities of heat removal are necessary for cooling of electronic devices. In this paper, based on a water-cooled smooth micro-channel heat sink, a series of rectangular-shaped flow obstructions are designed into a heat sink, and then the corresponding laminar flow and heat transfer have been analyzed numerically by computational fluid dynamics. Five different configurations of the flow obstructions are considered by adjusting the length of the flow obstructions. The influence of the length of the flow obstructions on heat transfer, pressure drop, and thermal resistance is also observed and compared to that of the traditional smooth micro-channel heat sink without flow obstructions. The overall resistance versus inlet Reynolds number and pumping power are also compared for whole micro-channel heat sinks (including smooth micro-channel heat sink). The results show that the capacity of heat removal of micro-channel heat sinks with flow obstructions is much better than that of the corresponding straight micro-channel heat sink. It is found that the length of the flow obstructions has a major influence on thermal performance. In other words, the flow obstructions placed in the micro-channel heat sink can improve thermal performance.