Parametric numerical study of the flow and heat transfer in microchannel with dimples

The characteristics of flow and heat transfer in microchannel with dimples were numerically investigated. The geometric parameters of dimpled channel, including aspect ratio, dimple depth and dimple spacing, were independently studied under constant Reynolds number 500. A constant heat flux 1 W/mm2 was adopted in the central area at the bottom of the microchannel heat sink to simulate a high power device. In comparison to straight channels, dimpled surface reduced the local flow resistance and also improved thermal performance of micro-channel heat sink. Compared to flat channel case, the optimal dimpled case has 3.2 K decrease of temperature, 15% gain of Nusselt number and 2% reduce of pressure drop.