Destabilizing turbulence in pipe flow

article Destabilizing turbulence in pipe flow published yes Jakob Kühnen author 3A47AE32-F248-11E8-B48F-1D18A9856A870000-0003-4312-0179 Baofang Song author Davide Scarselli author 40315C30-F248-11E8-B48F-1D18A9856A870000-0001-5227-4271 Nazmi B Budanur author 3EA1010E-F248-11E8-B48F-1D18A9856A870000-0003-0423-5010 Michael Riedl author 3BE60946-F248-11E8-B48F-1D18A9856A870000-0003-4844-6311 Ashley Willis author Marc Avila author Björn Hof author 3A374330-F248-11E8-B48F-1D18A9856A870000-0003-2057-2754 BjHo department Decoding the complexity of turbulence at its origin project Eliminating turbulence in oil pipelines project Turbulence is the major cause of friction losses in transport processes and it is responsible for a drastic drag increase in flows over bounding surfaces. While much effort is invested into developing ways to control and reduce turbulence intensities, so far no methods exist to altogether eliminate turbulence if velocities are sufficiently large. We demonstrate for pipe flow that appropriate distortions to the velocity profile lead to a complete collapse of turbulence and subsequently friction losses are reduced by as much as 90%. Counterintuitively, the return to laminar motion is accomplished by initially increasing turbulence intensities or by transiently amplifying wall shear. Since neither the Reynolds number nor the shear stresses decrease (the latter often increase), these measures are not indicative of turbulence collapse. Instead, an amplification mechanism measuring the interaction between eddies and the mean shear is found to set a threshold below which turbulence is suppressed beyond recovery. Nature Publishing Group2018 eng Nature Physics 1711.06543 00042943410002010.1038/s41567-017-0018-3 14386-390 https://research-explorer.ista.ac.at/record/12726 https://research-explorer.ista.ac.at/record/14530 https://research-explorer.ista.ac.at/record/7258 J. Kühnen, B. Song, D. Scarselli, N.B. Budanur, M. Riedl, A. Willis, M. Avila, B. Hof, Nature Physics 14 (2018) 386–390. Kühnen, J., Song, B., Scarselli, D., Budanur, N. B., Riedl, M., Willis, A., … Hof, B. (2018). Destabilizing turbulence in pipe flow. Nature Physics. Nature Publishing Group. <a href="https://doi.org/10.1038/s41567-017-0018-3">https://doi.org/10.1038/s41567-017-0018-3</a> Kühnen J, Song B, Scarselli D, Budanur NB, Riedl M, Willis A, Avila M, Hof B. 2018. Destabilizing turbulence in pipe flow. Nature Physics. 14, 386–390. J. Kühnen et al., “Destabilizing turbulence in pipe flow,” Nature Physics, vol. 14. Nature Publishing Group, pp. 386–390, 2018. Kühnen, Jakob, et al. “Destabilizing Turbulence in Pipe Flow.” Nature Physics, vol. 14, Nature Publishing Group, 2018, pp. 386–90, doi:<a href="https://doi.org/10.1038/s41567-017-0018-3">10.1038/s41567-017-0018-3</a>. Kühnen, Jakob, Baofang Song, Davide Scarselli, Nazmi B Budanur, Michael Riedl, Ashley Willis, Marc Avila, and Björn Hof. “Destabilizing Turbulence in Pipe Flow.” Nature Physics. Nature Publishing Group, 2018. <a href="https://doi.org/10.1038/s41567-017-0018-3">https://doi.org/10.1038/s41567-017-0018-3</a>. Kühnen J, Song B, Scarselli D, et al. Destabilizing turbulence in pipe flow. Nature Physics. 2018;14:386-390. doi:<a href="https://doi.org/10.1038/s41567-017-0018-3">10.1038/s41567-017-0018-3</a> 4612018-12-11T11:46:36Z2026-09-13T22:30:25Z