作者: Kenneth T Christensen ‡ , Ronald J Adrian
DOI: 10.1088/1468-5248/3/1/023
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摘要: Time-resolved particle-image velocimetry measurements are made in the streamwise-wall-normal plane of turbulent channel flow at Re τ = 550 and 1747. Temporal convective derivatives velocity computed from this data order to evaluate small-scale behaviour these quantities as well itself. Instantaneous fields indicate that is dominated by vortex cores believed be associated with hairpin/hairpin-like vortices. These vortices have been observed realizations random other wall turbulence studies. In work, a deterministic ‘vortex signature’ determined conditional averaging techniques. This average signature consistent hairpin defined Adrian co-workers: circular streamlines strong ejection low-speed fluid away (a Q 2 event) just upstream head. addition, spatial extent appears remain relatively cons...