Stationary wavelet-based analysis and simulation of unsteady wind in aeolian sand transport

摘要

To understand the effect of natural wind on sediment transportation,the stationary wavelet transform is utilized to analyze the time-frequency structure of gust measured in the Taklimakan desert. Based on the relationship between wavelet coefficients and turbulence energy structure,a method using the inverse stationary wavelet transform is proposed to generate artificial gust. The results show that the power spectrum of natural gust agrees with the Karman spectrum. Moreover,the gust in the near-surface layer exhibits explicit intermittency of turbulence. The low and high frequency parts of gust respectively determine the sediment transport in the general variation and the intermittency. The analysis of artificial gust and its comparison with natural wind demonstrate the validity of the presented method.