考虑尺度效应的微平板声振耦合特性研究

长宽厚均处于微米级的微平板结构广泛存在于微机电系统(MEMS)中,开展其声振耦合特性研究对于MEMS在声激励下的稳定性研究以及微型声传感器的性能研究具有重要意义.针对声压激励下的四边简支微平板结构,基于Cosserat理论与Hamilton变分原理建立了考虑尺度效应的结构声振耦合理论模型,并结合流固耦合条件求解了声振耦合系统控制方程.基于理论模型开展数值计算,系统研究了尺度效应对微平板结构声振耦合性能的影响,具体讨论了不同尺度效应下板厚度、板长宽等关键系统参数对微平板声振耦合特性的影响,为MEMS中微平板结构的工程优化设计提供了理论参考.

Vibroacoustic characteristics of micro-plates considering scale effect

Micro-plates of micron-size length, width and thickness are widely used in micro-electro-mechanical systems （MEMS）, therefore, the analysis on the vibroacoustic characteristic of micro-plates is of paramount importance to ensure the stability of MEMS under acoustic excitation and the accuracy of acoustic sensors. The vibroacoustic performance of micro-plates with simply supported boundary condition is theoretically investigated by applying Cosserat theory and Hamilton variational principle, which has taken into account the scale effect of the micro-plate. The resultant equations are solved in conjunction with fluid-structure coupling condition. The developed model is used to investigate the influences of the scale effect and several key parameters, including length, width and thickness of the micro-plates, on the vibroacoustic characteristic of micro-plates. The present model hopes to provide a theoretical reference for the engineering optimization design of micro-plates in MEMS.