Abstract Heat transfer enhancement studies were conducted on a variety of roughened microchannels for a laminar flow at 3≦Re≦25 with DI water as the cooling fluid. Five different discrete roughened surfaces, which were circular, square, triangular, elliptical, and hexagonal in shape, were used in the test channels with a channel cross-sectional area aspect (height to width) ratio of 0.25. The smooth-surface channel had a length of 30 cm, width of 200 μm, and height of 50 μm, which creates the hydraulic diameter of 80 μm for the study. A constant heat flux of 1.25 W/cm2 was applied to the bottom of the channel through the ITO surface. Results of the cooling performance in terms of the enhancement factor compared to those of a smooth channel found that the square pin-fin roughened surfaces had the best transfer enhancement followed by the ellipse, circle, hexagon, and triangle as compared to that of a smooth surface. Furthermore, axial wall heat conduction was noted for both smooth and roughened channels.

中文翻译：

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粗糙微通道中的低雷诺数对流传热增强

摘要 以去离子水作为冷却流体，对各种粗糙的微通道进行了3≤Re≤25的层流增强传热研究。在测试通道中使用了五个不同的离散粗糙表面，形状为圆形、方形、三角形、椭圆形和六边形，通道横截面面积纵横比（高宽比）为 0.25。光滑表面通道的长度为 30 cm，宽度为 200 μm，高度为 50 μm，这为研究创造了 80 μm 的水力直径。1.25 W/cm2 的恒定热通量通过 ITO 表面施加到通道底部。与光滑通道相比，冷却性能在增强因子方面的结果发现方形针翅粗糙表面具有最佳的传递增强，其次是椭圆，圆形、六边形和三角形与光滑表面相比。此外，对于光滑和粗糙的通道都注意到轴向壁热传导。