基于波动耦合的复杂结构动力响应分析与研究

有限元法(FEM)适合低频分析,统计能量分析(SEA)方法适合高频分析,而一类较宽频带(中频段)的声振响应问题不适合单独用FEM或SEA方法解决。基于波动耦合的混合FE-SEA方法兼顾了FEM与SEA方法的优点,可预测中频段含一定不确定性的声振系统的稳态响应。本文阐释了混合FE-SEA方法的理论,分别通过典型结构的蒙特卡罗仿真与复杂系统的噪声试验两案例对该方法进行了验证,其中梁-板典型结构能量响应计算值与蒙特卡罗仿真值具有较好的一致性;复杂飞行器系统的振动响应与试验结果较为吻合,舱内噪声声压级(SPL)误差小于3dB,证明了混合FESEA方法的有效性,解决了FEM与SEA方法在中频复杂声振响应中的局限性这一问题。

Analysis and research of dynamic response of complex structure based on wave coupling

The finite element method (FEM) is suitable for low-frequency analysis, while statistical energy analysis (SEA) method for high-frequency analysis, but a class of vibro-acoustic problem in a broad band (middle frequency) is not suitable for merely using the FEM or SEA method to solve. Taking the advantages of both FEM and SEA method, hybrid FE-SEA method based on wave coupling can predict the steady-state response of vibro-acoustic systems with a certain range of uncertainty. This article explains the theory of hybrid FE-SEA method and validates the method through two cases of Monte Carlo simulation of typical structure and the noise test of complex systems, and the energy response of the beam-plate composite structure has a good consistency with the value of Monte Carlo simulation; the vibration response of the complex aircraft''s vibro-acoustic systems agrees well with test result; the error of sound pressure level (SPL) in cabin is less than 3 dB; the two cases prove the effectiveness of the hybrid FE-SEA method, and the limitations of solving complex vibro-acoustic response using the FEM or SEA method at the middle frequency are overcome.