变均方根随机振动‒变加速度离心复合试验

Combined variable RMS random vibration and variable centrifugal acceleration test

为在地面试验中更真实地模拟再入飞行过载、振动力学环境的时变特性和复合特性,以再入飞行器子系统为对象,开展变均方根随机振动‒变加速度离心复合试验研究。设定试验条件时,对预示弹道过载数据进行平滑和重采样,得到变加速度离心试验条件;对实测振动数据频谱进行归一化和频谱加权融合,得到变均方根随机振动试验条件。复合试验结果表明,给出的试验条件控制可行,实现了再入飞行振动历程和过载历程的同时模拟。

To simulate more realistically the time history and the compound characteristics of the re-entry flight overload and the vibration environment in the ground test,an experimental study is proposed by combining the variable RMS random vibration test and the variable centrifugal acceleration test,on two re-entry vehicle subsystems.The variable centrifugal acceleration test conditions are derived from the nominal trajectory with smoothing and resampling.The vibration test conditions are based on the flight test data with the normalization and the weighted fusion of the frequency spectrum.The results of the new combined environmental test show that this test method is feasible for reproducing simultaneously the acceleration and vibration time history during the re-entry process.