摘要
The wind velocity spectra at Beijing Meteorological Tower are calculated using Hilbert-Huang transform and Fourier transform,respectively.A innovative model of wind velocity spectrum,which is accordant with the characteristics in both the inertial subrange and the large eddies range,is presented in this paper.The method of least squares is adopted to obtain the parameters in the model.Then the differences between the FFT spectrum and the HHT spectrum are compared.It is indicated that the values of the HHT spectrum in the energy containing range are slightly larger than those of the FFT spectrum while the values of the HHT spectrum in both inertial subrange and dissipation subrange are very close to that of Fourier spectrum.It is concluded that the HHT spectrum describes elaborately and accurately the spectrum values in the low frequencies and the fitted wind velocity model provides a reference for reconstructing the near-ground wind field of Beijing city in wind tunnel test and for numerical simulation.
基金
supported by the National Natural Science Foundation of China (Grant Nos. 90815021, 51021140005, 50978025, 50938008)
