基于本征模态修正的POD法在风场重建中的应用  

Reconstruction of fluctuating wind pressure field by applying POD of eigenvector correction

作　　者：邹垚[1] 梁枢果[1] 邹良浩[1] 

机构地区：[1]武汉大学,湖北武汉430072

出　　处：《土木工程学报》2010年第S1期305-309,共5页China Civil Engineering Journal

基　　金：国家自然科学基金(90715023)

摘　　要：POD法是风工程中常用的风场重建方法,但是在重建过程中,部分重建测点风压时程的方差与风洞试验数据相比会有140%以上的偏差。通过分析某高层建筑风洞试验的刚性模型测压试验数据,首先对结构表面风场进行POD时域分解,然后对主坐标进行频域分析,结果表明前3阶主坐标及其对应的本征模态值对重建风压时程的方差值起到91%以上的作用,其中第1阶主坐标的作用超过58%。最后以试验风压时程的方差值为目标,通过修正第1阶本征模态值,对偏差较大测点的风压场重建进行改进,使重建风场的方差值与实际风场方差值的差距缩小到10%以内。Proper Orthogonal Decomposition(POD) is a method which can be used to reconstruct fluctuating wind pressures fields.Errors produced by this method were observed bigger than 140% when comparing the results with wind tunnel test data.Wind tunnel tests for a high-rise building were carried out,by analyzing the wind pressures time series,the fluctuating wind pressure field of the structures were decomposed in time domain by POD,and the principal coordinates were analyzed in frequency domain.The results show that the 1st^3rd principal coordinate and the 1st^3rd eigenvector value have contributions greater than 91%,and the contribution of 1st principal coordinate is more than 58%.By correcting the first value of eigenvector target on variance value from wind tunnel test,the reconstruction results are better and the errors of variance are less than 10%.

关 键 词：本征正交模态法(POD) 风荷载模型 风洞试验 风场重建 模态修正 

分 类 号：TU312.1[建筑科学—结构工程]