具有不确定性声振系统的中频动力学分析及实验研究（英文）

Dynamic analysis and experimental study of vibro-acoustic system with uncertainties at middle frequencies

为考虑声-振结构中不确定性对系统动态响应的影响,提出了一种基于有限元方法(FEM)和统计能力分析法(SEA)相结合的混合方法.基于该方法,研究了具有不确定性的框架-板结构的中频动力学响应并以蒙特卡洛仿真结果为基准进行了对比分析.结果表明,框架-板结构的能量响应与蒙特卡洛仿真结果具有较好的一致性,验证了混合方法对具有不确定性复杂结构的中频声-振分析的有效性.基于混合FE-SEA方法,建立了具有随机特性的某工程机械驾驶室声-振模型,通过实验对模型的激励进行了测量.计算了驾驶室FE-SEA模型的声腔声压级响应与前风挡玻璃的振动功率谱密度响应,并通过实验进行了对比分析.在中频域内,二者有着较好的一致性,预测误差小于3.5dB.

To take into account the influence of uncetainties on the dynamic response of the vibro-acousitc structure, a hybrid modeling technique combining the finite element method（FE）and the statistic energy analysis（SEA） is proposed to analyze vibro-acoustics responses with uncertainties at middle frequencies. The mid-frequency dynamic response of the framework-plate structure with uncertainties is studied based on the hybrid FE-SEA method and the Monte Carlo（MC）simulation is performed so as to provide a benchmark comparison with the hybrid method. The energy response of the framework-plate structure matches well with the MC simulation results, which validates the effectiveness of the hybrid FE-SEA method considering both the complexity of the vibro-acoustic structure and the uncertainties in mid-frequency vibro-acousitc analysis. Based on the hybrid method, a vibroacoustic model of a construction machinery cab with random properties is established, and the excitations of the model are measured by experiments. The responses of the sound pressure level of the cab and the vibration power spectrum density of the front windscreen are calculated and compared with those of the experiment. At middle frequencies, the results have a good consistency with the tests and the prediction error is less than 3. 5dB.