摘要
本文介绍了一种多输入/多输出频域模态识别方法,并由计算机仿真和实际对称结构实例检验了本方法的精度、可靠性以及处理密集和重根模态的能力。文中给出了在某型现代歼击机全机地面振动试验中的应用,结果表明:和传统多点正弦激振相位共振技术相比,试验操作简单(无需调力),试验周期短,识别精度高;和80年代发展的多输入/多输出时域方法相比,能直接识别系统的阶(模态数),从而减少计算工作量,避免区分真实结构模态和“噪声模态”。
A frequency domain Muilti-Input/Multi-Output (MIMO) Modal Identification method is presented in this paper. Its accuracy, reliability and capability of handling closely-spaced or repeated modes are proved by computer simulation and real structure testing. The application in aircraft Ground Vibration Test (GVT) of a modern fighter is given. The results show that compared to traditional multipoint sine dwell GVT technique, the test operation is easier, the period is shorter and the accuracy is higher, compared to the time domain MIMO identification methods developed in 1980's, the order of the tested system (e. i. the number of modes) can be determined directly. Therefore, the computation is reduced, and the necessity of distinguishing structural and'noise'modes is avoided.
出处
《航空学报》
EI
CAS
CSCD
北大核心
1989年第1期A021-A027,共7页
Acta Aeronautica et Astronautica Sinica
关键词
地面振动
频域
模态
识别
aircraft grourd vibration, frequency response, modal analysis, system identification.
