The three-dimensional heat transfer and pressure drop of fluid flow within a microchannel with transverse vortex generator and porous medium are numerically investigated. A total of 14 cases with various designs of vortex generator, semi-porous, and completely porous material were studied in detail. Further, the performance is compared between microchannel with different heights and the number of transverse vortex generators, as well as a semi-porous microchannel with a vortex generator. The finite volume method is used to solve the governing equations based on the three-dimensional volume averaging method for single-phase laminar flow. The Darcy-Forchheimer model is applied to solve the flow in a porous medium. The computational domain includes a stainless steel rectangular microchannel with a vortex generator and/or the insertion of porous media. The numerical results indicate that the convective heat transfer coefficient increases with increasing height and the number of transverse vortex generators. Compared to the empty microchannel, the heat transfer coefficient is 12 times higher with a completely filled porous media and 2.6 times higher with eight vortex generators with 12.5% of the channel height. While pursuing a high heat transfer coefficient, the pressure drop of the fluid flow often also increases. Therefore, a thermal performance ratio is defined to normalize the change of heat transfer coefficient and pressure drop. The final combined results show that the microchannel with vortex generator and with top-and-bottom inserted porous media has the highest thermal performance ratio at low and high Reynolds number, respectively. Lastly, detail cross-sectional and down-the-channel flow streamlines and temperature distributions are shown to identify the fundamental mechanism of heat transfer. The findings of this study provide a comprehensive insight into designing an effective microchannel with optimal convective heat transfer and reasonable pressure drop.

数值研究了具有横向涡流发生器和多孔介质的微通道内流体流动的三维传热和压降。总共研究了14例不同设计的涡流发生器，半多孔和完全多孔材料的情况。此外，在具有不同高度的微通道和横向涡流发生器的数量之间以及具有涡流发生器的半孔微通道之间的性能进行了比较。基于三维体积平均法的单相层流，采用有限体积法求解控制方程。Darcy-Forchheimer模型用于求解多孔介质中的流动。计算域包括带有涡流发生器和/或插入多孔介质的不锈钢矩形微通道。数值结果表明，对流换热系数随高度和横向涡流发生器数量的增加而增加。与空的微通道相比，完全填充的多孔介质的传热系数高12倍，而具有通道高度的12.5％的八个涡流发生器的传热系数则高2.6倍。在追求高传热系数的同时，流体流的压降通常也增加。因此，定义热性能比以归一化传热系数和压降的变化。最终的综合结果表明，带有涡流发生器和顶部和底部插入的多孔介质的微通道分别在低和高雷诺数下具有最高的热性能比。最后，显示了详细的横截面和通道下方的流线和温度分布，以识别传热的基本机理。这项研究的发现为设计具有最佳对流传热和合理压降的有效微通道提供了全面的见解。