COOKIES: By using this website you agree that we can place Google Analytics Cookies on your device for performance monitoring. |
University of Cambridge > Talks.cam > Isaac Newton Institute Seminar Series > A large-eddy pathway to turbulent drag reduction at high Reynolds numbers
A large-eddy pathway to turbulent drag reduction at high Reynolds numbersAdd to your list(s) Download to your calendar using vCal
If you have a question about this talk, please contact nobody. TURW04 - Wall-bounded turbulence: beyond current boundaries Spanwise surface oscillation has been shown to be an effective drag reduction strategy for wall-bounded turbulent flows at low to modest Reynolds numbers (friction Reynolds numbers up to 1,000). Here, we present experimental measurements of substantial drag reduction at friction Reynolds numbers up to 12,800 using spanwise surface oscillations. The drag reduction was measured via a combination of drag balance and hot-wire anemometry. The drag reduction was found to occur via two distinct physical pathways. The first pathway, recognised from previous studies, involved actuating the surface at high frequencies, comparable to those of the small-scale eddies that dominate turbulence near the surface. The second pathway, however, was new and leveraged actuation at low frequencies comparable to those of the large-scale eddies farther from the surface. Importantly, this is accompanied with net-power savings due to the low actuation frequencies used. Insights into the underlying mechanism for the drag reduction will be discussed. This talk is part of the Isaac Newton Institute Seminar Series series. This talk is included in these lists:
Note that ex-directory lists are not shown. |
Other listsType the title of a new list here Perspectives from Cambridge Assessment Kettle's Yard 50th anniversaryOther talksWelcome and introduction Utopian Ambitions in the High Arctic at Resolute Bay Testability of relations between permutations Macroscopic Materials Assembled from Nanoparticle Superlattices A fractional generalisation of the Dirichlet distribution Cellular mechanisms of embryonic development and embryo-maternal interactions during implantation |