Improving the Sound Radiation froma Plate by Adding Inner Supportand Concentrated Mass

• Main Authors: Yu-Chao Yeh, 葉育超
• Other Authors: 陳國在
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/11778438635464236417

碩士 === 國立臺灣大學 === 工程科學及海洋工程學研究所 === 92 === The purpose of this study was focused on using the inner support and the additional centralization mass to refashion the fixed end sequare homogenous plate , and the subsequent improvement of the sound radiaton . We uses the radiation mode to find out the fundamental modes of more effective sound radiation . Then , the modes was broken by inner support with subsequently improved by additional centralization mass . All the supporting postion , the loading size and position of the additional mass are the topic of our study . The mathematical model was analyzed by semi-analytical method . We use the characteristics that the close form derived from the fundamental function and resonance frequency of homogenous plate , combining with structural dynamic and matrix , to deduce the result that the modified fundamental function and resonance frequency will save the CPU time effectively . We had proven it by simple experiment . The results revealed that , for single frequency noise , the plate vibration can be improved immediately and effectively if we used the refashion technology to change the resonance frequency for more than 5 Hz . Besides , it also can be applied to noise with arbitrary frequency to find out the best refashion position . We had proven that , even though with the different resonance frequency and noise peak frequency , the refashioned plate did reduce the general sound radiation effectively .