本文主要針對水平型橫流扇之性能提升進行設計改良， 首先根據原型橫流扇之幾何參數建模，並利用CFD 模擬軟體進行數值分析，透過流場分析並討論其缺失，如葉片扭轉角與背板幾何對流場之影響性，再藉由上述缺失提出水平型橫流扇之改良設計方案，依序的改良方案為外殼的設計、葉輪的改良以及擋板的加裝，模擬結果顯示，調整上、下背板曲率及葉輪角度改善皆有明顯的性能變化，其流量增幅分別為37.9%與51.6%；在擋板安置後流量總提升91.7%，壓力則有48.1%之增幅，其餘的幾何參數對性能各有消長，在橫流扇性能值得再進一步做探討。最後將水平型橫流扇製作成型並進入利用噪音與性能量測實驗，以獲取待測風扇之流量、壓力以及噪音等之風扇性能曲線。此外，為了確保實驗的可靠性，分別以AMCA201-85 規範進行性能測詴，並依照ISO-3745 及ISO-8753 標準規範，在半無響室進行聲壓噪音量測；經由實驗數據與模擬結果比對下，其兩者數據相當吻合，由此證明模擬結果有相當大的可信度。

An integrated CFD and experimental analysis is executed here to improve the performance of a horizontal cross-flow fan designed for the industrial computer. At first, the CFD code Fluent is used to simulate the flow field associated with the sample cross-flow fan; then, the flow visualization is performed numerically and analyzed carefully for identifying the reversed flow and circulation. Thereafter, several modifications are proposed for enhancing the aerodynamic performance of this sample cross-flow fan. In addition, a comprehensive parametric study is imposed to these design alternatives, which can be classified into three categories regarding to the housing, the rotor, and the blocking plate, respectively. Consequently, the appropriate housing geometry yields an apparent 37.9% increase on the airflow and a 22.2% decrease on its static pressure. And the optimized rotor results in an extra 13.7% enhancement on the volume flow rate while a minor pressure gain (6.5%) is recovered. Moreover, the blocking plate is imposed to install near the impeller at the fan inlet region for further performance improvement, especially the static pressure reinforcement.
In summary, the combination of these modifications successfully constructs a cross-flow fan generating a discharge airstream with a free-delivery flow rate and maximum static pressure at 14.05CFM and 1.37mmAq. This improved performance represents the outstanding 91.7% and 48.1% increases on flow rate and pressure characteristics, respectively. Thereafter, the prototype of the optimized fan is manufactured via CNC technique for experimental test to validate the CFD calculation. Furthermore, fan performance and acoustic experiment are conducted in an AMCA 210-99 test chamber and a semi-anechoic chamber following CNS-8753 code for ensuring a reliable test platform. Accordingly, the entire performance curve is in good agreement between the numerical and test results. In conclusion, this integrated, systematic design scheme not only yields the aerodynamic enhancement on cross-flow fan, but also provides the fan engineer’s design ability to meet with the performance requirement.

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