Heat transfer performance of microchannel heat sink with combined manifolds and bottom wall structures

The heat generated during operation gradually increases with the continuous miniaturization and integration of electronic components. High temperatures and thermal non-uniformity pose serious threats to the stability and reliability of the devices. Therefore, four bottom wall structures for manifold microchannel heat sinks were proposed, namely straight, wavy, zigzag, and right-angled triangle bottom walls. The results show that the rightangled triangle bottom wall exhibits optimal cooling performance, bottom wall temperature uniformity, and comprehensive temperature uniformity among these four structures. Additionally, 56 types of microchannel heat sinks with combined manifolds and right-angled triangle bottom walls for numerical study were designed. For bottom wall temperature uniformity and overall temperature uniformity, the optimal microchannel heat sink with combined manifolds and right-angled triangle bottom wall had a temperature uniformity factor and comprehensive temperature uniformity factor of 0.360 and 0.828, respectively. Compared to the straight bottom wall, the optimal right-angled triangle bottom wall reduced the temperature uniformity factor and comprehensive temperature uniformity factor by 16.86 % and 17.20 %, respectively. In terms of cooling performance, the optimal microchannel heat sink with combined manifolds and right-angled triangle bottom wall had an average temperature of the bottom wall of 324.02 K. Compared to the straight bottom wall, the optimal rightangled triangle bottom wall reduced the average temperature of the bottom wall by 4.07 K. This study provides valuable references for the design of microchannel heat sinks for high heat flux electronic devices.