基于双POD模型的空间相关三维随机风场数值模拟  

THREE-DIMENSIONAL NUMERICAL SIMULATION OF SPATIAL-CORRELATED STOCHASTIC WIND FIELD BASED ON DOUBLE POD MODEL

作　　者：潘峰[1] 孙炳楠[1] 陈勇[1] 

机构地区：[1]浙江大学土木工程学系,浙江杭州310027

出　　处：《工程力学》2008年第3期200-205,共6页Engineering Mechanics

基　　金：国家自然科学基金资助项目(50378085,50708096)

摘　　要：POD法提供了一种高效、准确的风荷载模拟方法,通过对风场的功率谱密度矩阵进行Schur分解,得到一系列的特征值和特征向量,选取主要的几阶特征模态进行计算就可以得到比较精确的结果。该文讨论了具有空间相关性三维随机风场的数学模型,利用双POD模型和蒙特卡罗模拟法,详细描述了空间相关三维风场的数值模拟方法。通过大跨越输电塔三维风场的数值模拟研究表明,模拟的顺风向、横风向、竖直向风速的功率谱密度函数与理论值较为符合,并且具有较好的随机性。证实了该文提出的方法是一种高效、准确的结构三维风场模拟方法,并可应用于大跨空间结构、高层建筑及大跨度桥梁等结构之中。The mathematical models of stochastic processes for a spatial-correlated wind velocity field has been proposed. The proper orthogonal decomposition （POD） technique offers an efficient and accurate tool to simulate the fluctuating components of the wind field. Using Schur decomposition method, the power spectral density matrix can be expressed by a series of eigenvalues and eigenvectors. It is recognized that only a small number of eigeumodes corresponding to eigenvalues with larger magnitudes are dominant. In the practical, it can ignore some of the higher eigeumodes associated with smaller eigenvalues. Based on the double POD model and Monte Carlo framework, a very efficient simulation scheme for the three correlated turbulence components is proposed. The simulation procedure is applied to a high transmission tower and the results show out that the procedure presented in the paper can be an accurate and effective method to simulate the stochastic wind field which has time and space correlativity. The method can also be used in some other structures such as large-span spatial structures, high-rise buildings, long-span bridges, and so on.

关 键 词：双POD模型 蒙特卡罗模拟 三维风场 功率谱密度矩阵 输电塔 

分 类 号：O343.2[理学—固体力学] TU312.1[理学—力学]