Abstract In this article, the effects of convex dimple streamwise arrangements on the flow and heat transfer characteristics of protrusion-grooved channels are determined, and five streamwise positions of convex dimples are considered. In addition, research on the transverse-circular-protrusion-grooved channel is also performed to serve as a contrast. The results indicate that replacing the transverse-circular-protrusion with the convex dimple produces a counter-rotating vortex pair, and the streamwise arrangements of the convex dimple significantly affect the flow structure downstream of the convex dimples. As the convex dimple is moved downstream, the velocities near the center protrusion-grooved surface increase till a maximum occurs for the case of a convex dimple placed at the center between adjacent grooves, and then decrease. Compared with the case of transverse-circular-protrusion, the convex dimple at the center region can enhance the overall heat transfer rate, while if it approaches the adjacent grooves lower heat transfer rate appears. Besides, replacing the transverse-circular-protrusion with the convex dimple can significantly reduce the pressure loss penalty and enhance the thermal performance factor. In addition, the effect of streamwise arrangements of convex dimples on the friction factor is slight, but the case with the center convex dimple exhibits the best overall thermal performance.

中文翻译：

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凸凹流向排列对矩形凸凹槽通道流动传热特性影响的数值研究

摘要 本文确定了凸凹坑流向排列对凸槽通道流动和传热特性的影响，并考虑了凸凹坑的五个流向位置。此外，还对横向圆形凸槽通道进行了研究以作为对比。结果表明，用凸凹坑代替横向圆形突起产生了一个反向旋转的涡对，凸凹坑的流向排列显着影响了凸凹坑下游的流动结构。随着凸凹处向下游移动，中心突起-凹槽表面附近的速度增加，直到在凸凹处放置在相邻凹槽之间的中心的情况下出现最大值，然后减小。与横向圆形凸起的情况相比，中心区域的凸凹坑可以提高整体传热率，而如果靠近相邻的凹槽，传热率就会降低。此外，用凸凹坑代替横向圆形突起可以显着降低压力损失损失并提高热性能系数。此外，凸凹坑的流向排列对摩擦系数的影响很小，但中心凸凹坑的情况表现出最佳的整体热性能。用凸凹坑代替横向圆形突起可以显着降低压力损失损失并提高热性能系数。此外，凸凹坑的流向排列对摩擦系数的影响很小，但中心凸凹坑的情况表现出最好的整体热性能。用凸凹坑代替横向圆形突起可以显着降低压力损失损失并提高热性能系数。此外，凸凹坑的流向排列对摩擦系数的影响很小，但中心凸凹坑的情况表现出最好的整体热性能。