泵為應用相當廣泛之流體機械，凡有需輸送液體流動之處，幾乎都會看到泵的蹤跡，從民生農業灌溉用抽水機、自來水公司抽水機到工業上化工廠裡的製程泵、核能廠的冷卻泵等。在現今生活中節能成為人類目前的一大課題，離心泵的內流場表現也就顯得格外重要，唯有良好的設計才能在正常運作下達到最佳揚程的效果，工作流體要從離心泵內流場得到良好的獵能效果，就必須針對會造成揚程損耗的低剪應力區域做診斷，故本研究將針對離心泵進行流場分析，葉輪在離心式幫浦流場中佔有主導性之地位，故本研究將嘗試改變葉輪之幾何參數在葉輪內流場來縮小低剪應力區域造成的損耗現象，建立最佳化的葉輪設計，透過低剪應力區域流場分析後，本研究在設計點Qd流量下，葉片壓力側圓弧PSR71、葉片吸入側圓弧SSR67上得到最好的性能表現，揚程增加1.4%，在大於設計點Qd 流量(過載流量; Over-load)下PSR71揚程增加7.03%。

Centrifugal pumps have a wide range of applications including agricultural irrigation, household water treatment, liquid transport in industrial plants, reactor cooling in nuclear power plants, etc. Meanwhile, in present days, energy saving has become a critical issue for human beings. And to maximize the efficiency of centrifugal pumps at their design operation flowrate (Qd), it is important to minimize the inevitable head loss in their internal flow field through blade geometry optimization. In this work, we demonstrate that the blade geometry can be modified systematically so as to reduce the area on the blade surfaces where the fluid shear stress is low, thereby reducing the head loss as well. An optimized impeller blade design then can be identified. Specifically, our case study starts with the baseline design in which the blade surfaces are circular arcs, having radii of curvature of PSR=60 mm on the pressure side (PS) and SSR=57 mm on the suction side (SS). The optimized radii of curvature that minimizes the low-shear region are found to be PSR=71 mm and SSR=67 mm, which increases the head at Qd by 1.4%, and increases the head at the overload flowrate of 1.39 Qd by 7.03%.

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