【摘要】 根据颤振试验的原理和观测信号特点,提出一种时频域滤波方法。该方法通过对信号进行自适应分解并求其时频谱,进而在联合时频域对其进行滤波重构。主要用于飞机颤振试验信号的预处理,对颤振模态参数提取与颤振边界预测有着直接的意义。数字仿真及物理试验验证了该方法的有效性和可行性。更多还原

【Abstract】 According to the principles and signal properties of flutter test,a new filtering algorithm in time-frequency domain is presented.As pre-processing of aircraft flutter test signals,the method is valuable for the succeeding processes including extraction of mode parameters and flutter boundary prediction.By the method,observational signal is decomposed adaptively to obtain the time-frequency spectrum;subsequently,the spectrum is filtered by the designed pass-zone function in the domain of joint time-frequency;and then signal of time history is reconstructed from the filtered spectrum.The functions of the method are investigated by digital simulation and further examined by using flutter testing data of low-speed wind-tunnel of some aeroelastical models.The results show that the method is effective in improving the precision of FBP and feasible in engineering tests.更多还原