A Model of the Two-dimensional Spectrum of Wind Fluctuations during Strong Winds and its Applications to the Engineering

[摘要] The two-dimensional spectra of wind fluctuations in a horizontal plane in the surface boundary layer of the atmosphere are obtained, which are calculated from a simple model founded upon the experimental formulate of the one-dimensional power spectrum and upon the coherence between velocities at two points.The variations of the two-dimensional spectra obtained from the present model with a height and a decay parameter are discussed.The two-dimensional spectra are . obtained as a function of the non-directional wave numbers, and their features in the wave number range corresponding to the inertial subrange are discussed in relation to the decay parameter.Applications of the two-dimensional spectrum to the engineering are briefly mentioned. The one-dimensional spectrum of wind fluctuations spatially averaged over the lateral distance, which is of use for the estimation of the wind load on the line-like rigid structures, is obtained making use of the two-dimensional spectrum.

[学科分类] 大气科学