针对时不变平稳系统,建议了计算线性随机振动响应功率谱密度的一种实数域虚拟激励算法.基本原理是根据哈特莱变换与傅里叶变换之间的关系构造系统的实数型虚拟激励和实数型系统函数,计算结构的实数型虚拟振动响应,由实数型虚拟激励和虚拟响应计算结果确定系统随机振动响应的功率谱密度.研究结果表明,该方法可以方便地处理随机激励问的相关性和相干性,与传统的复数型虚拟激励法相比较,只需确定实数型虚拟激励和在频域计算实数型虚拟响应,就能精确算出结构随机振动响应的功率谱密度,计算形式比较简单和可行.%A real domain pseudo-excitation method ( PEM) was proposed for computing the power spectral density ( PSD) of a linear time-invariant system subjected to stationary stochastic external excitations. Using this method, with the relationship between Hartley transformation and Fourier transformation real pseudo excitaptions were constructed and the real transfer function of the system was determined, then the real pseudo response of the system and its PSD of random vibration responses were computed. The results showed that the statistical correlativity and coherence among the excitations can be easily evaluated; compared with the traditional complex field PEM, the proposed method uses real pseudo excitations and real pseudo responses to evaluate the PSD of structural random vibration responses, it is simpler and practicable.
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