Phase-averaged waveforms of Reynolds stress in wall turbulence during the burst events of coherent structures  

作　　者：JIANG Nan LIU Wei LIU JianHua TIAN Yan 

机构地区：[1]Department of Mechanics,Tianjin University,Tianjin 300072,China [2]Tianjin Key Laboratory of Modern Engineering Mechanics,Tianjin 300072,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2008年第7期857-866,共10页中国科学：物理学、力学、天文学（英文版）

基　　金：the National Natural Science Foundation of China (Grant No. 10472081);the Program for New Century Excellent Talents in Universities of Ministry of Education of China, ;Tianjin Science and Technology Development Plan (Grant No. 06TXTJJC13800)

摘　　要：The time sequence signals of instantaneous longitudinal and normal velocity components at different vertical locations in the turbulent boundary layer over a smooth flat plate have been finely measured by constant temperature anemometry of model IFA-300 and X-shaped hot-wire sensor probe in a wind tunnel. The longitudinal and normal velocity components have been decomposed into multi-scales by wavelet transform. The upward eject and downward sweep motions in a burst process of coherent structure have been detected by the maximum energy criterion of identifying burst event in wall turbulence through wavelet analysis. The relationships of phase-averaged waveforms among longitudinal velocity component, normal velocity component and Reynolds stress component have been studied through a correlation function method. The dynamics course of coherent structures and their effects on statistical characteristics of turbulent flows are analyzed.The time sequence signals of instantaneous longitudinal and normal velocity components at different vertical locations in the turbulent boundary layer over a smooth flat plate have been finely measured by constant temperature anemometry of model IFA-300 and X-shaped hot-wire sensor probe in a wind tunnel. The longitudinal and normal velocity components have been decomposed into multi-scales by wavelet transform. The upward eject and downward sweep motions in a burst process of coherent structure have been detected by the maximum energy criterion of identifying burst event in wall turbulence through wavelet analysis. The relationships of phase-averaged waveforms among longitudinal velocity component, normal velocity component and Reynolds stress component have been studied through a correlation function method. The dynamics course of coherent structures and their effects on statistical characteristics of turbulent flows are analyzed.

关 键 词：wall TURBULENCE coherent structure BURST wavelet transform REYNOLDS stress phased-averaged WAVEFORM 

分 类 号：O357.5[理学—流体力学]