000013992 001__ 13992
000013992 005__ 20161115094007.0
000013992 04107 $$aeng
000013992 046__ $$k2016-08-21
000013992 100__ $$aGriffin, Kevin
000013992 24500 $$aCorrelated forcing with an active grid to control turbulence

000013992 24630 $$n24.$$p24th International Congress of Theoretical and Applied Mechanics - Book of Papers
000013992 260__ $$bInternational Union of Theoretical and Applied Mechanics, 2016
000013992 506__ $$arestricted
000013992 520__ $$2eng$$aResearch on classical turbulence theory has benefited from the use of active grids that allow a wider range of flow conditions to be generated than their passive counterparts [1]. We used a new type of active grid with 129 independently rotating paddles to imprint different correlations into wind tunnel turbulence. The grid’s control over the RMS fluctuation velocity and integral length scale allowed the turbulence Reynolds number Re; to be held constant and isotropy to be controlled. We then imposed correlations into the otherwise random motions of the paddles through convolution with kernels of different shape. At constant Res, the velocity correlation functions collapsed into different families based on kernel shape when scaled by the integral length scale, regardless of flow anisotropy. This suggested that the active grid could change the structures in the flow. The exceptional degree of control over flow properties offered by these methods could allow hypotheses about the influence of large-scale structure on the various properties of turbulence to be tested more precisely and extensively.

000013992 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000013992 653__ $$a

000013992 7112_ $$a24th International Congress of Theoretical and Applied Mechanics$$cMontreal (CA)$$d2016-08-21 / 2016-08-26$$gICTAM2016
000013992 720__ $$aGriffin, Kevin
000013992 8560_ $$ffischerc@itam.cas.cz
000013992 8564_ $$s146075$$uhttps://invenio.itam.cas.cz/record/13992/files/PO.FM14-1.10.173.pdf$$yOriginal version of the author's contribution as presented on CD, XMLout( page 1483, code PO.FM14-1.10.173).
000013992 962__ $$r13812
000013992 980__ $$aPAPER