本研究中是以CFD流體模擬分析軟體 ANSYS CFX(17.0版)，針對所設計出不同的吸頭幾何形狀(入口與出口間形狀採用直線幾何或曲線幾何)，探討不同幾何設計之收縮區對於真空裝置吸頭流場特徵之影響。在模擬域出風口邊界條件之相對總壓力設定為0 Pa，進風口速度邊界條件為10m/s，以及牆面邊界條件為No-slip wall的條件下，模擬出幾何內部流場的情況後，對於模擬得到的結果進行觀察。模擬結果指出，初步模擬出此兩種幾何形狀的其中之A TYPE壓損係數 (Static pressure loss coefficient)為0.85，低於B TYPE之總壓損係數0.19。且經過觀察指標壓損係數、模擬數值以及流場特徵的比較之後，可以歸納出B TYPE幾何設計較A TYPE幾何相對來說，吸頭性能有較佳的表現。最後在結果比較中也發現B TYPE吸頭存在著些微影響性能的設計問題，因此在本研究結論中也指出了B TYPE吸頭的修正方向，如此未來才能針對設計進行更好的修正，呈現出更好的產品性能。

In this paper, the CFD fluid simulation software ANSYS CFX (version 17.0) was used to validate different suction nozzle geometries (linear or curved geometry of the side wall between inlet and outlet) and to explore the influencing factors of different geometric designs for the vacuum device. The influence of the different geometric design factors on the flow field characteristics of the suction nozzle on the vacuum device has been explored. The inlet boundary condition, which is the average velocity of an internal domain, is set to 10 m/s, the outlet boundary condition total pressure is set to 0 Pa atmospheric pressure, and the wall boundary condition is set to No-slip wall.
After the analysis via simulation, the results indicate that the static pressure loss coefficient of the A TYPE geometry is 0.85, which is higher than the B TYPE geometry (0.19). And after comparing the static pressure loss coefficient (observation index with the simulation value) and the flow field characteristics, it can be concluded that the B TYPE geometric design has a better flow field performance than the A TYPE geometry design.
After completing the discussion of the relative relationship between the flow field characteristics and the geometric design, it is also possible to realize the design principles of the suction nozzle at the inlet of the vacuum type product.

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