空旷平坦地面非平稳强风湍流特性研究

发布时间：2018-03-23 23:12

本文选题：风速实测　切入点：经验模态分解　出处：《振动与冲击》2014年23期

【摘要】：根据1128h的实测强风风速样本,对某空旷平坦地貌下10 m高度处的非平稳强风风场湍流特性进行了研究。基于平均风速在基本时距内的平稳性,建立了非平稳强风风场的平稳风速模型和非平稳风速模型,分别计算这两类模型下的各风场湍流特征参数并加以对比。结果表明:55%的实测风速样本具有较强的非平稳性,采用非平稳风速模型更能反映实际风场风速;研究湍流特征参数随平均风速的变化规律,其中湍流强度随风速变化不明显,主要集中在0.16~0.20,大于我国现行荷载规范规定的B类场地10 m高度湍流度值0.14;阵风因子随平均风速减小,湍流积分尺度则随之增大;相对于其他风速谱,Davenport谱更能准确描述强风风场的能量分布。
[Abstract]:Based on the measured strong wind velocity sample of 1128 h, the turbulent characteristics of non-stationary strong wind field at 10 m height in an open flat landscape are studied. The stationary wind speed model and the non-stationary wind speed model of the non-stationary strong wind field are established. The turbulent characteristic parameters of each wind field under these two models are calculated and compared respectively. The results show that 55% of the measured wind speed samples have strong nonstationarity. The non-stationary wind speed model can better reflect the wind speed of the actual wind field, and the variation of turbulence characteristic parameters with the average wind speed is studied, in which the turbulence intensity does not change obviously with the wind speed. It is mainly concentrated at 0.16 ~ 0.20, which is larger than the turbulence degree of 10 m height of class B site stipulated in the current load code of our country, and the gust factor decreases with the average wind speed, and the turbulence integral scale increases with the decrease of the mean wind speed. Compared with other wind speed spectra, Davenport spectrum can accurately describe the energy distribution of strong wind field.
【作者单位】：河南省电力试验研究院;浙江大学土木工程学系;
【基金】：国家电网公司科技项目国家自然科学基金面上项目(51178424)
【分类号】：TU312.1

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