caa a22 4500 477093280 CHVBK 20180405111520.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00191018 doi (NATIONALLICENCE)springer-10.1007/BF00191018 Structure of near wall turbulence downstream of a wall mounted protrusion: an interesting Reynolds stress suppression phenomena [Elektronische Daten] [A. Fontaine, S. Deutsch] A local suppression in the generation of near wall Reynolds stress is achieved by modifying the buffer region and sublayer (y + <30) of a turbulent pipe flow with a 16.4 wall unit high wall mounted protrusion. Multi-component, multi-point, time resolved laser Doppler velocimetry measurements are made in the undisturbed and modified ARL/PSU glycerin tunnel pipe flow at a Reynolds number of approximately 10000. A downstream converging flow field is produced by the divergence of the approaching mean flow around the protrusion. A pair of counter-rotating vortices, ≈ 15 wall units in diameter with common flow down, are generated by the protrusion and also contribute to the wall directed flow convergence. The convergence region is 15 wall units high and more than 100 wall units long and appears to decouple the near wall region from the outer turbulent wall layer. Locally, turbulent velocity fluctuations in the form of Reynolds stress producing events, sweeps and ejections, are retarded within this region. This results in a reduction in near wall uv Reynolds stress and local wall shear. Interestingly, the counter-rotating vortices act to increase turbulent diffusion in a manner which is uncorrelated with Reynolds stress generation. Springer-Verlag, 1996 Fontaine A. Chemical Engineering Dept., Georgia Institute of Technology, 778 Atlantic D1., 30332-0100, Atlanta, GA, USA aut Deutsch S. Applied Research Laboratory, The Pennsylvania State University, USA aut Experiments in Fluids Springer-Verlag 20/5(1996-03-01), 365-376 0723-4864 20:5<365 1996 20 348 https://doi.org/10.1007/BF00191018 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00191018 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Fontaine A. Chemical Engineering Dept., Georgia Institute of Technology, 778 Atlantic D1., 30332-0100, Atlanta, GA, USA aut NATIONALLICENCE 700 1- Deutsch S. Applied Research Laboratory, The Pennsylvania State University, USA aut NATIONALLICENCE 773 0- Experiments in Fluids Springer-Verlag 20/5(1996-03-01), 365-376 0723-4864 20:5<365 1996 20 348 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer