Laboratory Simulation Study of Characteristic of Large Scale Coherent Structure Movement in Entrainment Layer

Abstract

Abstract:

Large scale coherent structure, a physical phenomenon of major importance in atmospheric boundary layer, is observed in laboratory tank simulation. By analyzing its scintillation characteristic in beam pattern, it’s found that the structure corresponds to the long and bright stripe in beam pattern, and the peak in scintillation index profile, so its vertical average velocity could be obtained by the spatial cross-correlation of scintillation index. And, by means of spatial correlation, vertical movement characteristics of large scale coherent structure at boundary layer top are studied. The results show that, the large-coherent structure at the boundary layer top, mainly with very slow speed, drives the developing of boundary layer top.

Key words: entrainment layer, large scale coherent structure, laboratory simulation, beam pattern, spatial correlation

CLC Number:

P401

LUO Tao, YUAN Ren-Min, LU Chao, WU Xu-Ping, SUN Jian-Ning. Laboratory Simulation Study of Characteristic of Large Scale Coherent Structure Movement in Entrainment Layer[J]. Journal of Atmospheric and Environmental Optics, 2009, 4(6): 432-440.

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