Abstract In present work, a miniature rectangular groove (MRG) is arranged at the bottom of the rectangular channel, and an effective slip surface is constructed. The flow and heat transfer characteristics in the channel with MRG are numerically investigated by Large Eddy Simulation. The results show that the fluid flows over the spanwise vortices inside MRG rather than over the non-slip solid surface. Therefore, effective slip velocity occurs at the interface between the fluid inside and outside the MRG, which reduces the velocity gradient nearby the MRG. Meanwhile, the spanwise vortices inside the MRG are similar to rolling bearings which exert an additional driving force on the external fluid of MRG to propel the fluid moves forward. Furthermore, the influence range of MRG on the flow field is different upstream and downstream of the MRG, respectively. The result indicates the Nusselt number is closely related to the spanwise vortex intensity of the channel bottom. The slightly strengthened spanwise vortices at the leading and trailing edges of the MRG enhance the fluid mixing and the heat transfer performance is improved to some extent. Compared with the channel without MRG, the effective slip surface can improve heat transfer performance and obtain drag reduction.

中文翻译：

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有效滑移面对通道内流动传热特性的影响

摘要 在目前的工作中，在矩形通道的底部设置了一个微型矩形凹槽（MRG），并构建了一个有效的滑动面。通过大涡模拟对具有 MRG 的通道中的流动和传热特性进行了数值研究。结果表明，流体在 MRG 内部的展向涡旋上流动，而不是在防滑固体表面上流动。因此，有效滑移速度出现在 MRG 内外流体的界面处，这降低了 MRG 附近的速度梯度。同时，MRG内部的展向涡流类似于滚动轴承，对MRG的外部流体施加额外的驱动力，推动流体向前运动。此外，MRG对流场的影响范围在MRG上游和下游不同，分别。结果表明，努塞尔数与通道底部展向涡强度密切相关。MRG 前后缘略有加强的展向涡流增强了流体混合，传热性能得到了一定程度的提高。与没有MRG的通道相比，有效滑移面可以提高传热性能并获得减阻。