“音响虫”驱动薄板的振动特性有限元分析  

Finite element analysis of the vibration characteristics of thin board actuated by a ‘soundbug'

作　　者：姜广军[1] 莫喜平[2] 

机构地区：[1]吉林建筑大学城建学院,长春130111 [2]中国科学院声学研究所,北京100190

出　　处：《声学技术》2013年第6期486-489,共4页Technical Acoustics

摘　　要："音响虫"是一种利用宽带线性激励器将任意硬质、光滑的板状物体转化为类似平板扬声器的小装置。采用Terfenol-D磁致伸缩材料驱动,几乎能将任何平面作为共鸣板驱动发声,它的不同音色就决定于被激励的薄板(木材、金属、玻璃、塑料等)。利用有限元方法模拟了"音响虫"激励薄板的振动特性,分析了一些典型材料薄板的振幅-频率响应、几个频率下的振动位移分布以及30Hz^16kHz频率范围内的自由振动模态数。根据这些结果并比较平板扬声器的工作原理,分析"音响虫"激励薄板发声的音质问题可以得出以下结论:"音响虫"激励板状结构振动发声,在中高频段的音响特性较好,当被激励薄板为声速较大的材料时,在高频段一般能获得较好的音响效果,当被激励薄板为声速较小的材料时,中低频段具有较好的音响特性。在此基础上对"音响虫"的应用和音质改善提出一些建议。＇Soundbug＇ is a device using a wideband linear actuator to convert any hard or smooth board as a flat panel speaker. This device is driven by magnetostrictive material Terfenol-D and can turn nearly any flat surface into a soundboard. Its timbre is differentiated from the material of the board （wood, metal, glass, plastic and etc.）. Finite ele- ment method was used to simulate the vibration characteristics of the board actuated by a soundbug. For some typical materials of the boards, the amplitude-frequency responses, displacement distributions at some special frequencies, and the number of free vibration modes in the frequency range from 30 Hz to 16 kHz were analyzed. From the simulation results and the comparison with a flat panel speaker, conclusions are drawn as follows. The acoustics of the board ac- tuated by a soundbug at mid-high frequency band is good. For a board of higher sound velocity material, the acoustics performance is also good at high-frequency band. For a board of lower sound velocity material, the acoustics perfor- mance is good at low-mid frequency band. In addition, suggestions about the application of soundbugs and the im- provement of their timbre are proposed.

关 键 词：音响虫 有限元方法 振动特性 自由振动模态 

分 类 号：TB54[理学—物理]