基于演化相位谱的脉动风速模拟

Evolutionary-phase-spectrum based simulation of fluctuating wind speed

基于理性分析,提出了一种演化相位谱模型,并由此发展了脉动风速模拟方法。根据湍流中不同频率涡旋的特征速度,提出了相位演化速度这一概念,进而说明具体的风速时程可由所有初始相位为零的涡旋经过时间Te演化而来。通过对实测脉动风速Te值的识别和统计,给出了Te的概率分布。据此,可以得到演化相位谱的样本,结合Fourier幅值谱,应用逆Fourier变换便可进行脉动风速模拟。所建立的演化相位谱模型是对Fourier相位谱的一种理性描述,可用于各种结构抗风计算及可靠度分析的风荷载模拟当中。

Based on rational analysis,an evolutionary-phase-spectrum model which can be used in fluctuating wind speed simulation was proposed.According to the characteristic speed of eddies with different frequencies in turbulence,the concept of phase-evolving speed was put forward.Afterwards,it was illustrated that real wind speed history can be regarded as the evolutionary results of eddies with initial phases of zero after an evolutionary time Te.The probability distribution of Te was calculated through statistics of the identified values from measured fluctuating wind speed histories.Then,samples of evolutionary-phase-spectrum were acquired and combining.With Fourier amplitude spectrum,fluctuating wind speed was obtained through inverse Fourier transform.The evolutionary-phase-spectrum model is a rational description of Fourier phase spectrum and is recommended to be used in wind load simulation in wind-resistance calculation and reliability analysis of structures.