限带白噪声随机过程的雨流幅值概率密度函数模型

Probability Density Function Model of Rainflow Amplitude for Random Process of Band⁃Limited White Noise

对17种不同带宽系数的限带白噪声随机过程进行了雨流循环计数统计,提出了一个限带白噪声随机过程的雨流幅值概率密度函数(Probability density function,PDF)模型。该模型是Rayleigh分布和Weibull分布的线性组合,其中待定系数均为随机过程谱参数的函数。采用该模型对这17种随机过程的雨流幅值概率密度函数进行了公式拟合,探究了模型中待定参数与随机过程谱参数之间的关系,确定了模型表达式。对照随机过程的雨流计数统计结果,将该模型与Dirlik模型的预测精度进行了比较,结果表明该模型的预测效果优于Dirlik模型。

The rainflow cycle counting is carried out on seventeen random processes of band-limited white noise with different band widths,and a probability density function(PDF)model of rainflow amplitude for random processes of band-limited white noise is proposed.This model is a linear combination of a Rayleigh distribution and a Weibull distribution,where the undetermined coefficients are all functions of the spectral parameters of the random process.Data fitting is carried out on the rainflow amplitude PDFs of the seventeen random processes based on the proposed model,and the relationship between the parameters in the model and the spectral parameters of the random processes are investigated,and the formula of the model is determined.According to the rainflow cycle counting results of the random processes,the prediction accuracy of the proposed model is compared with that of Dirlik’s model,which shows that the proposed model gives better prediction results than Dirlik’s model.