考虑脉动压力相关性的自由体随机振动分析

Random Vibration Analysis of Free Body Under Fluctuating Pressure Considering Correlation

目的获得自由体在脉动压力载荷作用下的结构响应。方法采用有限元方法,建立锥壳自由体结构的随机振动分析有限元模型,根据自由体的脉动压力载荷和随机振动分析理论,计算自由体在脉动压力下的加速度响应均方根值。结果载荷为一定程度相关时的计算结果在完全相关和不相关之间,最小相差约15%,最大相差约50%。结论在进行自由体结构脉动压力下的响应分析时,载荷间的相关性是不能忽略的,分区加载可改善计算精度。

In order to obtain the structural response of the free body under a fluctuating pressure load,a finite element model of the random vibration analysis of the conical shell free body structure is established by using the finite element method.According to the random vibration analysis theory,the RMS value of acceleration response under free body fluctuating pressure is calculated based on the pulsating pressure load on the free body.When the loads are correlated to a certain degree,the calculation results are between the fully correlated and uncorrelated calculation results,the minimum difference being about 15%,and the maximum difference being about 50%.The calculation result shows that the correlation between loads can not be ignored when performing response analysis of free body structure under fluctuating pressure,and partition loading can improve calculation accuracy.