現今電子產品不斷發展小尺寸電子零件的情況下，廢熱排放已成為重要的議題，主要方式以風扇搭配Sink、熱管，來達到散熱的功能；而今風扇仍扮演著主要的角色，本文有鑑於此，設計離心扇外殼搭配斜流扇葉輪，發展新式風扇研究其不同情況下性能的表現，以提供更多解決方案。本文首先設計一風扇尺寸，觀察其流場並改善後以Fan A表示，再以Fan A為基礎進行不同參數的研究，舉凡葉片曲率半徑、葉片內徑、舌部起始角、入口直徑及葉片高度等等，探討其各個參數對流場的影響以及其最佳設計範圍。經過數值模擬我們得知除了葉片高度，均可提升風扇性能且有最佳值存在，其中以葉片內徑可提升性能與減噪功能，其他參數較無法同時滿足。為了驗證模擬的準確性，本文挑選葉片曲率半徑、葉片內徑、舌部安裝角及入口直徑等參數，將風扇實體以CNC製作出來，再以AMCA所規範之出口式風洞以及CNS8753聲壓量測技術，測量風扇性能與噪音。其實驗結果顯示，模擬與實驗誤差在10%以內，P-Q Curve整體趨勢亦相當一致，在所有風扇之中，以改變葉片內徑可以得到較低的噪音，性能提升則以改變入風口直徑最為顯著。

This work aims to design a small blower for the thermal task of laptop computers by using an integrated scheme, which consists of fan design, mockup manufacture, experimental verification, and numerical simulation. In the fan design, a high-performance fan (60×60×15 mm3) is constructed with the aids of flow visualization on the entire flow patterns via the CFD means. Then, to further enhance fan performance and realize the corresponding influences caused by varying the fan geometry, a parametric study is executed with the emphasis on the rotor inner diameter, the blade curvature, the cut-off angle, and the inlet diameter. Thereafter, prototypes are manufactured by the CNC machine to carry out the corresponding experimental verifications. To ensure a reliable outcome, the fan’s performance and noise tests are performed in the AMCA-210 and semi-anechoic chambers following CNS-8753 code. The experimental results show that the deviations between numerical simulations and experiments are within 10%. This fact represents a great potential to reduce the expensive and tedious experimental work by using CFD tools. Besides, the results show that there is an optimum value existed for each parameter considered here. Also, the dominant parameters for increasing the aerodynamic performance and noise reduction of a blower are the inlet diameter and the blade curvature, respectively. In addition, an extensive discussion on these parameters is summarized to serve as the design guideline for small cooling blowers for notebook computers.

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