摘要
为定量分析风速时间序列的内在波动性，采用分形维数方法进行研究。就分形维数结果的准确程度比较了盒维数法和结构函数法，当曲线维数大于1．3时，使用盒维数求分形维数误差较大，而利用结构函数法求分形维数，误差小于1％。使用结构函数法计算了地表粗糙度分别为0．01～2．5m下不同风数据的分形维数，在相同平均风速条件下，风速序列随地表粗糙度增大，其分形维数减小。
To quantitatively analyze the internal fluctuation in the time sequence of wind speeds, the frac- tal dimension method was used to conduct an investigation. The box-counting dimension and structural function methods were compared in terms of the accuracy of the results calculated by using the fractal di- mension calculation method. When the dimension of a curve is greater than 1.3, the error of the fractal di- mensions calculated by using the box-counting method was relatively big. However, the error of the fractal dimensions calculated by using the structural function method was less than 1%. The structural function method was employed to calculate the fractal dimensions under various wind data when the ground surface roughness was in a range from 0.01 m to 2.5 m. At a same average wind speed,the wind speed sequence increased with an increase of the ground surface roughness and the fractal dimension of the wind speed decreased.
作者
王广
沈昕
竺晓程
杜朝辉
WANG Guang;SHEN Xin;ZHU Xiao-cheng;DU Chao-hui(College of Mechanical and Power Engineering, Shanghai Jiaotong University, Shanghai, China, Post Code： 20024)
出处
《热能动力工程》
CAS
CSCD
北大核心
2018年第2期124-128,共5页
Journal of Engineering for Thermal Energy and Power
关键词
湍流风
地表粗糙度
分形维数i
turbulent wind, ground surface roughness, fractal dimension
