航空发动机振动环境谱统计归纳方法及振动试验台复现

Aeroengine Vibration Environment Spectrum Statistical Induction and Reproduction on Vibration Testing Table

为满足航空发动机及机载产品研制过程贴近使用环境的振动考核试验需求,需根据发动机实测振动数据给出振动考核试验所需的输入谱图。依据GJB/Z 126-99中给出的环境测量数据归纳方法,建立了发动机实测振动环境谱统计归纳方法并通过程序实现。利用发动机多架次实测试飞振动数据统计归纳得到发动机测点位置的振动实测谱。基于能量等效及信号频域特征分布一致原则,将归纳得到的实测谱转化为可用于振动台输入的振动环境谱,并在振动台上进行了振动信号的复现试验。结果表明:振动台输出信号与发动机实测振动信号频域分布特征一致,在统计频率带宽范围内振动总量最大相差5.7%,证明了转化方法是合理的,为航空发动机机载设备贴近使用环境的振动考核试验方法提供了真实的输入谱图。

To meet the requirements of conducting vibration assessment tests under conditions close to the operating environment for the development of aeroengine and airborne products,it is necessary to provide the input spectrum required for the vibration assessment test based on the measured engine vibration data.Based on the induction method of environment measurement data provided in GJB/Z 126-99,a statistical induction method for vibration environment spectra measured engine vibration data was established and implemented through a program.The measured vibration spectra at engine measuring positions were obtained by statistical induction according to vibra⁃tion data from multiple actual test flights.Based on the principle of energy equivalence and consistent distribution of signal frequency domain characteristics,the spectra obtained using the induction method were converted into vibration environment spectra which can be used as the input for the vibration testing tables,and experiments for vibration signal reproduction were conducted on vibration testing tables.The results show that the frequency domain distribution characteristics of the output signal of the vibration testing table are consistent with that of the measured engine vibration signal.The maximum difference in the overall vibration within the statistical frequency bandwidth is 5.7%,which proves the rationality of the conversion method and the capability of providing real input spectra for vibration assessment tests of aeroengine airborne equipment under conditions close to the service environment.