【摘 要】
：
A consequence of nonlinearities is a multi-harmonic response via a mono-harmonic excitation.A similar phenomenon also exists in random vibration.The power spectral density (PSD) analysis of random vibration for nonlinear systems is studied in this paper.T
【机 构】
：
State Key Laboratory of Structural Analysis for Industrial Equipment,Faculty of Vehicle Engineering
论文部分内容阅读
A consequence of nonlinearities is a multi-harmonic response via a mono-harmonic excitation.A similar phenomenon also exists in random vibration.The power spectral density (PSD) analysis of random vibration for nonlinear systems is studied in this paper.The analytical formulation of output PSD subject to the zero-mean Gaussian random load is deduced by using the Volterra series expansion and the conception of generalized frequency response function (GFRF).For a class of nonlinear systems,the growing exponential method is used to determine the first 3rd-order GFRFs.The pro-posed approach is used to achieve the nonlinear system\'s output PSD under a narrow-band stationary random input.The relationship between the peak of PSD and the parame-ters of the nonlinear system is discussed.By using the proposed method,the nonlinear characteristics of multi-band output via single-band input can be well predicted.The results reveal that changing nonlinear system parameters gives a one-of-a-kind change of the system\'s output PSD.This paper provides a method for the research of random vibration prediction and control in real-world nonlinear systems.
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