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Experimental study of flow reattachment in a single-sided sudden expansion
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TLDR
The importance of changing the structure of the separated shear layer on the reattachment process itself was examined in this article, where the authors developed a pulsed wall probe for measurement of skin friction in the re-attachment region, thus providing an unambiguous definition of the Reattachment length.Abstract:
The reattachment of a fully turbulent, two dimensional, separated shear layer downstream of a single-sided sudden expansion in a planar duct flow was examined experimentally. The importance of changing the structure of the separated shear layer on the reattachment process itself was examined. For all cases, the Reynolds number based on step height was greater than 20,000, the expansion ratio was 5/3, and the inlet boundary layer was less than one-half step height in thickness. A crucially important phase was the development of a pulsed wall probe for measurement of skin friction in the reattachment region, thus providing an unambiguous definition of the reattachment length. Quantitative features of reattachment - including streamwise development of the mean and fluctuating velocity field, pressure rise, and skin friction - were found to be similar for all cases studied when scaled by the reattachment length. A definition of the reattachment zone is proposed.read more
Citations
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An experimental investigation of a turbulent shear flow with separation, reverse flow, and reattachment
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The structure of a turbulent shear layer bounding a separation region
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Direct numerical simulation of turbulent flow over a backward-facing step
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Journal ArticleDOI
The reattachment and relaxation of a turbulent shear layer
Peter Bradshaw,F. Y. F. Wong +1 more
TL;DR: In this article, the authors show that the splitting of the shear layer at reattachment, where part of the flow is deflected upstream into the recirculating flow region to supply the entrainment, causes a pronounced decrease in eddy length scale, evidently because the larger eddies are torn in two.
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