摘要
研究对输电塔线体系随机脉动风场进行高效数值模拟的方法。根据输电塔线体系结构特点和风场特性,对于输电塔,可只考虑顺风向与横风向的脉动风,并认为两个方向的风速相互独立,将其简化为两个独立一维风场。而对于输电线,考虑横风向与竖风向的脉动风,并认为两者存在相关性,进行二维多变量脉动风场模拟。为减少传统谐波叠加法中对功率谱矩阵Cholesky分解的计算量,采用Hermite插值进行目标函数拟合,通过快速傅里叶变换技术加快三角级数的叠加。此外,应用正交随机变量的谱表示法,将随机函数表示为两个基本随机变量的多项式的正交函数,与已有的相关方法相比,随机变量降维后所需生成的随机过程的代表性时程的数量可以更少。最后数值算例验证了所采用模拟方法的高效性。
Here,effective simulation of stochastic fluctuating wind field of transmission tower-line system was investigated.For the transmission tower,only downwind and crosswind fluctuating winds were considered and simplified as two independent 1-D wind fields.For transmission lines,fluctuating winds in cross and vertical directions were considered and simulated as correlated 2-D fluctuating wind fields.Hermite interpolation was used to fit the objective function,and reduce computation amount of Cholesky decomposition of power spectral matrix in the traditional harmonic superposition method.Fast Fourier transform(FFT)technique was also adopted to accelerate the superposition of triangular series.In addition,the spectral representation method of orthogonal random variables was used to express a random function as an orthogonal function with 2 elementary random variables in form of polynomials.Compared with other existing approaches,the number of representative time histories of generated random processes needed after dimension reduction of random variables could be less.Finally,numerical examples verified the high efficiency of the proposed simulation method.
作者
杨雄骏
黄金山
张建国
雷鹰
YANG Xiongjun;HUANG Jinshan;ZHANG Jianguo;LEI Ying(School of Architecture and Civil Engineering,Xiamen University,Xiamen 361005,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2021年第9期77-83,共7页
Journal of Vibration and Shock
基金
国家重点研发计划项目(2017YFC0803300)。
关键词
脉动风场
输电塔线
HERMITE插值
谱表示
降维模拟
fluctuating wind field
transmission tower-line system
Hermite interpolation
spectral representation
dimension reduction simulation
