Numerical Simulation of a Novel Complex Fan

• Main Authors: Wang Yih Wen, 王藝文
• Other Authors: Shian Chun Lin
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/15912662745863062164

碩士 === 國立臺灣科技大學 === 機械工程系 === 93 === 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.