Abstract Microchannel heat sink (MCHS) is an advanced cooling technique to fulfil the cooling demand for electronic devices installed with high-power integrated circuit packages (microchips). Various microchannel designs have been innovated to improve the heat transfer performance in an MCHS. Specifically, the utilisation of nanotechnology in the form of nanofluid in an MCHS attracted the attention of researchers because of considerable enhancement of thermal conductivity in nanofluid even at a low nanoparticle concentration. However, a high-pressure drop was the main limitation as it controls the MCHS performance resulted from heat transfer augmentation. Therefore, this study aimed to critically summarise the challenges and limitations of both single and hybrid passive methods of MCHS. Furthermore, the performance of nanofluid as a coolant in the MCHS as affected by the type and concentration of nanoparticle and the type of base fluid was reviewed systematically. The review indicated that the hybrid MCHS provides a better cooling performance than MCHS with the single passive method as the former results in a higher heat transfer rate with minimal pressure drop penalty. Besides that, further heat transfer performance can be enhanced by dispersing aluminium dioxide (Al2O3) nanoparticles with a concentration of less than 2.0% (v/v) in the water-based coolant.

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通过先进的几何结构和纳米流体回顾微通道散热器应用中的被动方法：当前的进步和挑战

摘要 微通道散热器（MCHS）是一种先进的冷却技术，可以满足安装有大功率集成电路封装（微芯片）的电子设备的冷却需求。已经对各种微通道设计进行了创新，以提高 MCHS 中的传热性能。具体而言，在 MCHS 中以纳米流体形式使用纳米技术引起了研究人员的注意，因为即使在低纳米颗粒浓度下，纳米流体的热导率也显着提高。然而，高压降是主要限制因素，因为它控制了由传热增强引起的 MCHS 性能。因此，本研究旨在批判性地总结 MCHS 单一和混合被动方法的挑战和局限性。此外，系统地审查了纳米流体作为 MCHS 中冷却剂的性能受纳米颗粒的类型和浓度以及基液类型的影响。审查表明，混合 MCHS 比采用单被动方法的 MCHS 提供更好的冷却性能，因为前者导致更高的传热率，同时压降损失最小。除此之外，通过将浓度小于 2.0% (v/v) 的氧化铝 (Al2O3) 纳米颗粒分散在水基冷却剂中，可以进一步提高传热性能。审查表明，混合 MCHS 比采用单被动方法的 MCHS 提供更好的冷却性能，因为前者导致更高的传热率，同时压降损失最小。除此之外，通过将浓度小于 2.0% (v/v) 的氧化铝 (Al2O3) 纳米颗粒分散在水基冷却剂中，可以进一步提高传热性能。审查表明，混合 MCHS 比采用单被动方法的 MCHS 提供更好的冷却性能，因为前者导致更高的传热率，同时压降损失最小。除此之外，通过将浓度小于 2.0% (v/v) 的氧化铝 (Al2O3) 纳米颗粒分散在水基冷却剂中，可以进一步提高传热性能。