在現今電子產品的設計中，產品微小化是大家所追求的目標，但也由於體積小，與外界進行熱交換的面積會減少許多，因此我們可預知的電子元件單位面積的熱通量也會大幅提升，因此如何設計良好的幾何結構，增加固體熱傳及流體之對流效應為本研究之重點。
本文藉由Ansys Fluent模擬三維穩態的環境下，微型散熱器於不同內部幾何結構時其強制對流熱傳效應，透過不同模型的比較，提出結構改善的設計理念，並進行一系列的參數分析與討論，瞭解經過結構設計後之流道對於參數的影響性，使得在3D列印此項技術下，能夠有別於以往的製程限制達到新的結構設計。
根據模擬結果可以得知在內部結構為燒結多孔材料、多孔結構與矩形流道下，溫控能力為燒結多孔材料最佳，但所需付出的壓降遠大於矩形流道，在考量經濟效益的前提下，本文往改善矩形流道幾何結構的方式來進行探討。
在不同流道幾何結構下，左右漸縮流道擁有壁面最高溫度的抑制能力，波浪形流道則可得到最低的平均壁面溫度；左右漸縮流道之局部熱對流係數變化較為平緩，可瞭解到此結構在壁面溫度的分佈上較為平均，不會因為熱量過度集中於某段部位，而造成熱應力的損壞；於局部熱傳增益值中，左右漸縮流道在流道後段其值有更巨幅地成長，代表有更多的能量能在流道後段被帶走，符合預期設計理念。
在同一種幫浦功率之下，波浪形流道能得到最大的平均紐賽數，而於FOM結果中所有改善後的流道其值均略小於1，且在左右漸縮流道中，FOM值則會隨著雷諾數變高而有所下降。儘管如此，改善後的結構設計確實能夠得到更佳的溫控效果及緩合壁面的溫度分佈，因此伴隨著3D列印技術的成長與進步，微型散熱器具特殊內部幾何結構設計於電子散熱領域之應用，將具有無限之發展與潛力。

In this study, several interior structure models are developed to numerically investigate the effects of force convection and heat transfer in micro heat sink which is applied on cooling high power electronic components. These structures include sintered porous material, porous structure and rectangular channel. According to the results, the interior structure with sintered porous material has better operating temperature control ability than the others, but its pressure drop between inlet and outlet is much larger than rectangular channel. So improving rectangular channel geometry is chosen in this study.
The channel structures are redesigned including trapezoid, right-left(R-L) converged, top-bottom(T-B) converged, and wave geometry. The result shows that R-L converged channel has the best temperature control ability and its local heat transfer coefficient varies smoothly with flow direction, so the electronic component will not fail due to thermal stress concentration. Moreover, with the same pumping power, all the designed channels can get higher nusselt number and lower operation temperature than the rectangular channel. So, with the growth of 3D printing technology, the micro heat sink with different interior structure for cooling high power electronic components will have the unlimited development and potential in the future.

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