The structure of turbulent flow in a rectangular channel containing a cylindrical rod - Part 1: Reynolds-averaged measurements

Flow visualization and hot-wire anemometry were used to investigate the iso thermal velocity field in a rectangular channel containing a single cylindr ical rod, focussing on the gap region between the rod and a plane wall. Mea surements reported in this paper, which is part 1 of a two-part series, inc lude the variations of the Reynolds-averaged mean velocity, wall shear stre ss and turbulent stresses. The presence of large-scale, quasi-periodic stru ctures in the vicinity of the gap, for a range of gap widths, has been demo nstrated through flow visualization, spectral analysis and space-time corre lation measurements. The above measurements appear to be compatible with th e field of a street of three-dimensional, counter-rotating vortices, whose convection speed and streamwise spacing have been determined as functions o f the gap width. (C) 2000 Elsevier Science Inc. All rights reserved.