Thermal management for multi-cores chips through microchannels completely or incompletely filled with ribs

Abstract

Microchannels have attracted significant attention in the thermal management of integrated circuits due to their small geometrical size and high heat transfer efficiency. Motivated by further improving the thermal management capacity of microchannels in multi-cores chips with lower pressure drop penalty, in this paper, a comparative investigation on four different configurations was conducted through numerical simulation for the Reynolds number ranging from 200 to 800 to analyze the comprehensive effects of filling mode and rib arrangement on the flow and heat transfer characteristics, including microchannel completely filled with aligned ribs (MCFAR), microchannel incompletely filled with aligned ribs (MIFAR), microchannel completely filled with staggered ribs (MCFSR) and microchannel incompletely filled with staggered ribs (MIFSR). Moreover, the entropy generation rate is used to estimate the irreversibility of flow and heat transfer based on the second law of thermodynamics. Finally, the performance evaluation criteria (PEC) is adopted to estimate the overall performance. The results show the flow patterns in the MIFAR and the MIFSR are different from those in the MCFAR and the MCFSR due to the incomplete filling mode, which could induce more dramatic disturbance and further break the downstream boundary layer, thus the heat transfer could be enhanced with a lower pressure drop penalty. The analysis of entropy generation rate indicates that entropy generated by heat transfer contributes the majority of the total entropy generation thus enhancing the heat transfer is a more important and effective approach in reducing the irreversibility. Among the four configurations researched, the microchannel MIFAR shows the best overall performance (PEC = 1.76) when Re = 400.

Keywords

• Microchannel
• Ribs
• Heat transfer
• Pressure drop
• Numerical simulation