Abstract Heat sinks are always in the center of electronic cooling researchers' attention. Microchannels are utilized in electronic cooling devices owing to their increased surface and better thermal performance than that of normal heat sinks. In this numerical investigation, the first and second laws of thermodynamics impact of twisted porous ribs on the microchannel are studied. The effects of the Reynolds number, the Hartman number, and the volume fraction of nanoparticles are investigated. The range of the dimensionless number for the Hartmann number and the Reynolds number is 0 to 20 and 250 to 1000, respectively. All types of microchannel in this study consist of clear microchannels in two groups; group one (No. 1, 2 and 3) and group two (No. 4, 5, and 6). The obtained results show that at the end of each porous rib, the reported parameters depict a decrease. Twisted porous ribs cause a significant decrease in the expanding thermal boundary layer. Also, the microchannel with triple-layer porous ribs (No. 3) exhibits considerable performance in the entropy generation. Finally, since group one has a double pitch, it has the better thermal performance and increasing the Hartmann number is one of the reasons for the increasing velocity gradient near the microchannel wall and friction factor.

中文翻译：

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磁场对具有不同多孔层和节距的扭曲多孔肋的影响：用两相方法研究热力学第一定律和第二定律

摘要 散热器一直是电子冷却研究人员关注的焦点。微通道由于其比普通散热器增加的表面积和更好的热性能而被用于电子冷却设备。在此数值研究中，研究了扭曲多孔肋对微通道的热力学第一定律和第二定律的影响。研究了雷诺数、哈特曼数和纳米颗粒体积分数的影响。哈特曼数和雷诺数的无量纲数的范围分别是 0 到 20 和 250 到 1000。本研究中所有类型的微通道均由两组透明微通道组成；第一组（第 1、2 和 3 号）和第二组（第 4、5 和 6 号）。得到的结果表明，在每个多孔肋的末端，报告的参数描述了减少。扭曲的多孔肋条导致膨胀的热边界层显着减少。此外，具有三层多孔肋条的微通道（第 3 号）在熵产生方面表现出可观的性能。最后，由于第一组具有双节距，因此具有更好的热性能，并且增加哈特曼数是微通道壁附近速度梯度和摩擦系数增加的原因之一。