本研究主要之目的是設計出適合現今筆記型電腦內部空間及散熱需求的高效能電腦冷卻風扇，風扇整體尺寸大小為60×60×15 mm3，此新型風扇是兼具傳統離心扇及橫流扇之設計特點，希望此複合扇能具有橫流風扇之高流量低噪音及離心扇之高靜壓的優點，使其能在筆記型電腦之有限空間內發揮最大的效能。首先以符合氣動力性質之NACA4410 翼型設計出扇葉，再搭配具有蝸形流道的風扇外殼，最後以CNC加工製作出原型風扇，並以符合AMCA210規範之實驗設備進行風扇性能量測，同時依照CNS-8753之標準規範，在半無響室進行聲壓噪音量測，最後藉由調整外殼與葉輪的幾何參數的組合，找出性能最好之新型複合式風扇。在數值模擬方面則分為三部份來觀察分析，第一部份是將實驗所得最佳設計參數組合之複合式風扇，以電腦數值計算軟體(STAR-CD)模擬其內外流場之實際狀況；第二部份是將複合式風扇之上下進風口封閉，以觀察比較傳統式橫流扇與複合式風扇之流場差異所在；最後則是縮小馬達Hub之尺寸，模擬比較不同尺寸之Hub對風扇整體流場之影響，藉由各種不同設計狀況之流場比較分析，以提出相關之改善建議，使得此新型風扇之整體設計能更加完善。

In this study, the purpose is to devise a novel complex fan, which can meet the requirement of internal space and cooling desire of notebook computer. Overall volume of innovated complex fan is 60×60×15 mm3, and it is consisted of the design features of centrifugal and cross-flow fans. High airflow rate of cross flow fan and the high static pressure of centrifugal fan are the advantages on performance of complex fan. First of all, the centrifugal rotor is designed with the NACA4410 airfoil, and it is fitted in the spiral housing. The prototype is made by CNC machine and tested to serve as reference for further modification. All the performance and noise experiments are executed in AMCA 210-99 chamber and semi-anechoic chamber, respectively. Thereafter, a parametric study on fan geometry is performed to realize the influences caused by those variations. From experimental result, the complex fan yield a better output than the sample does. In numerical analysis, the simulation is divided into three portions. First portion, the optimum complex fan in the experimental program is simulated via the CFD software (STAR-CD). Then, for understanding the flow patterns, the open holes of top and bottom plates are sealed in order to simulate the traditional cross flow fan. Finally, the flow field of complex fan is simulated with various hub size of motor. All recommendations of improvement are raised to enhance the performance characteristics of complex fan via comparing the experiment and simulation result. In summary, while the noise level is kept roughly at the same level, compared to the reference available in the current market, an impressive 4.92 CFM airflow with 6.82 mm-Aq static-pressure gain are delivered by the complex fan with an optimum geometrical parameters operating at 3000rpm.

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