Purpose

This numerical study aims to investigate the modification of the hexagonal pin fin geometry to enhance both the thermal and hydraulic performance of the copper micropin fin heat sink with single-phase water coolant in a laminar regime. The heat sink performance evaluation criteria have been investigated for the parametric effects of vertex angle θ (10–120) and relative length (RL) (0.25–9) of hexagonal pin fins.

Design/methodology/approach

To carry out research and reduce the computational cost, only one heat sink unit is simulated and analyzed using periodic boundary conditions on the side walls and includes a hexagonal pin fin and half channel on both sides to reflect the structural characteristics completely. The governing equations are also solved using finite volume method.

Findings

The results reveal that θ = 60 and RL = 1 yield the optimum thermal performance and heat sink performance is significantly influenced by the vertex angle and RL. The modified hexagon geometry improves fluid flow behavior by reducing the volume of the recirculation region behind the pin fin, preventing its effects on the downstream pin fins and restricting the thermal boundary layer development on its straight side. At Re = 1,000, the modified geometry enhances the average Nusselt number by 24.46% and the thermal performance factor by 23.89%, demonstrating the potential of modified hexagonal pin fins to enhance micropin fin heat sink performance.

Originality/value

Prior studies suggest using the pin fins with a regular hexagonal cross-section to obtain better thermal performance. However, this comes with a higher pressure drop penalty. The modification of the hexagonal pin fin geometry has been investigated in this numerical study to enhance both the thermal and hydraulic performance of the micropin fin heat sink. Because little attention has been paid to the modification of the regular hexagonal pin fins, as a geometry inspired by natural honeycomb structures, its design optimization is relatively scarce, and a gap was felt in this field.

中文翻译：

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改进的六角形针翅片可增强微针翅片散热器的热工水力性能

目的

本数值研究旨在研究六角形针翅片几何形状的修改，以提高层流状态下使用单相水冷却剂的铜微针翅片散热器的热性能和水力性能。研究了六角形针鳍顶角θ（10~120）和相对长度（RL）（0.25~9）参数效应对散热器性能评价标准的影响。

设计/方法论/途径

为了开展研究并降低计算成本，仅对一个散热器单元进行侧壁周期边界条件模拟分析，并在两侧包括六角形针鳍和半通道，以完整地反映结构特征。控制方程也用有限体积法求解。

发现

结果表明，θ = 60 和 RL = 1 可产生最佳热性能，并且散热器性能受顶角和 RL 的显着影响。改进的六边形几何形状通过减少针翅片后面的再循环区域的体积来改善流体流动行为，防止其对下游针翅片的影响并限制其直边上的热边界层的发展。在 Re = 1,000 时，修改后的几何形状将平均努塞尔数提高了 24.46%，热性能因数提高了 23.89%，证明了修改后的六角形针鳍片在增强微针鳍片散热器性能方面的潜力。

原创性/价值

先前的研究建议使用具有规则六边形横截面的针鳍以获得更好的热性能。然而，这会带来更高的压降损失。本数值研究对六角形针翅片几何形状的修改进行了研究，以增强微针翅片散热器的热性能和水力性能。由于正六边形针鳍的改造较少受到关注，作为一种受天然蜂窝结构启发的几何形状，其设计优化相对匮乏，在该领域感到有差距。