随机振动下偏心隔振系统仿真分析

针对存在严重偏心的机载设备，通过载荷解耦计算各点支撑承受质量载荷，确定隔振系统固有频率，计算系统的刚度和阻尼；将系统中隔振器简化为线性弹簧阻尼单元，建立隔振系统的有限元模型，采用基础运动法分析隔振系统在随机振动下的加速度响应，最后根据试验结果优化隔振器的刚度和阻尼，使隔振系统的Y向在随机振动下的加速度响应误差从44.95%降到7.47%，固有频率误差从37.43%降到-0.25%，其他两个方向的仿真误差也都显著降低，获得较精确的隔振系统动力学模型，为偏心机载设备隔振设计提供指导依据。

Simulation Analysis of an Eccentric Isolation System under Random Vibration

Aiming at an off-center airborne equipment, each mount load was calculated by load decoupling and the nature frequency of the system was calculated, as well as stiffness and damping. The finite element model was established in which the isolators were instead of linear spring dashpot elements. The acceleration response of the isolation system was analyzed by base motion method. At last, according to test results, parameter optimization method was used to modify the stiffness and damping of the isolator of the finite element model. After optimization, the error of the acceleration response of the Y direction of the system decreases from 44.95% to 7.47%; the error of the nature frequency decreases from 37.43% to -0.25%. And the error of the other two directions decrease evidently and an accurate dynamic model of the system was gained. It provides an analysis method for an off-center airborne equipment isolation design under random vibration.