摘要
从湍流理论的基本方程出发,根据Taylor关于湍流的"冻结"假定,导出了湍流脉动风压谱密度函数的解析计算公式。在分析过程中考虑了压力控制方程源项中全部"紊动-剪切"项的影响。若取用合适的湍流积分尺度,则由此公式得出的横风向脉动风压谱密度函数值与足尺观测数据相吻合。在接近建筑物第一阶自振频率附近谱值函数高于由风洞实验得出的结果。因此根据湍流脉动风压谱密度函数计算得出的结构横风向风振动力反应位移值与加速度值均高于由日本规范公式等计算得出的值。
According to Taylor＇s Frozen Assumption about turbulence, an analytical solution of spectral density function of pressure fluctuation in across-wind direction was derived from the governing equation of flow movement in turbulence theory. All of the turbulence-mean components in the source term of pressure governing equation had been taken into account. If an appropriate turbulence integral scale is adopted, the spectrum density function value will correspond well to the results from full scale measurements. The function value near the basic natural frequency of building is larger than that from wind tunnel test. The displacement and the acceleration value evaluated with this fluctuating pressure load are larger than those from Japanese design code.
出处
《工程力学》
EI
CSCD
北大核心
2007年第10期80-86,共7页
Engineering Mechanics
基金
国家自然科学基金项目(50078003)
关键词
脉动风压
谱密度函数
湍流
傅氏变换
对流速度
相关函数
随机过程
fluctuating wind pressure
spectral density function
turbulence
Fourier transform
convective velocity
correlation function
stochastic process
