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2017年4月18日 Acoustic characteristics of damped metamaterial plate with parallel attached resonators

发布时间:2017-04-14  点击次数:1406

 主  办:力学系、材料系联合邀请
报告人:Prof.Qinghua Qin
时  间:2017年4月18日 周二 下午3:40―4:40
地  点:力学楼434室
主持人:李法新 研究员 报告内容简介: An acoustic metamaterial consisting of a homogeneous damped plate with parallel attached resonators is presented in this report. Theoretical analysis shows that multiple resonant-type band gaps are obtained, in which the lower bound frequency of each band gap coincides with the resonance frequencies of the resonators; Compared with the metamaterial plate with resonators attached in series reported by Peng and Pai (2015), parallel arrangement of the resonators causes a larger width and smaller lower bound of the second band gap while the first band gap keeps almost the same, which makes an easier combination of the multiple band gaps into a wider one. It is noted that damping has significant influence on the band gaps and the effective mass density. Specifically, damping can broaden the band gaps with the sacrifice of the deactivating the band gap effect, smooth and lower the frequency responses for the whole ranges. Comparatively, damping from the host plate can smooth and reduce the responses in low-frequency range (lower than the first band gap), while damping of the resonators can move the unbounded effective mass density region to a lower frequency and shrinks the negative-density ranges by means of damping out part of energy. Finite element simulation reveals that the metamaterial plateworks on the mechanism of multiple conventional vibration absorbers generating inertia forces to counteract the bending forces induced by the flexural waves and stretching the plate within the band gaps. Practical implementation of the metamaterial plate with two different configurations is also discussed to show the potential applications for engineering.  

报告人简介:

 

Qing-Hua Qin年和1994―王宽诚基金赴德国1995年到清华大学作博士后研究;2002研究员和2004、研究中心材料加工制造组的带头人等职位。2002多篇期刊论文,出版J. G. Russell<span calibri","sans-serif";="" mso-ascii-font-family:="" "times="" new="" roman";="" mso-hansi-font-family:="" mso-fareast-language:="" zh-cn'="">奖。<span lang="EN-AU" times="" new="" roman","serif";="" mso-fareast-language:="" zh-cn'="">                                                                                                欢迎校内外同仁莅临!

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