Journal article

The smooth-wall-like behaviour of turbulence over drag-altering surfaces: a unifying virtual-origin framework

Joseph I Ibrahim, Garazi Gomez-de-Segura, Daniel Chung, Ricardo Garcia-Mayoral

JOURNAL OF FLUID MECHANICS | CAMBRIDGE UNIV PRESS | Published : 2021

Abstract

We examine the effect on near-wall turbulence of displacing the apparent, virtual origins perceived by different components of the overlying flow. This mechanism is commonly reported for drag-altering textured surfaces of small size. For the particular case of riblets, Luchini et al. (J. Fluid Mech., vol. 228, 1991, pp. 87–109) proposed that their effect on the overlying flow could be reduced to an offset between the origins perceived by the streamwise and spanwise velocities, with the latter being the origin perceived by turbulence. Later results, particularly in the context of superhydrophobic surfaces, suggest that this effect is not determined by the apparent origins of the tangential ve..

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University of Melbourne Researchers

Grants

Awarded by Engineering and Physical Sciences Research Council (EPSRC)


Awarded by EPSRC


Awarded by Australian Research Council


Awarded by EPSRC Tier-2 grant


Funding Acknowledgements

J.I.I. was supported by the Engineering and Physical Sciences Research Council (EPSRC) under a Doctoral Training Account, grant number EP/M506485/1. G.G.-d.-S. was supported by EPSRC grant EP/S013083/1. D.C. gratefully acknowledges the support of the Australian Research Council Discovery Project DP170102595. This work was also partly supported by the European Research Council through the 2nd Coturb Madrid Summer Workshop. Computational resources were provided by the `Cambridge Service for Data Driven Discovery' operated by the University of Cambridge Research Computing Service and funded by EPSRC Tier-2 grant EP/P020259/1, and by the DECI resource Cartesius, based in the Netherlands at SURFSara, with support from PRACE.