The near-wall region of highly turbulent Taylor–Couette flow
| dc.contributor.author | Ostilla-Mónico, Rodolfo | |
| dc.contributor.author | Verzicco, Roberto | |
| dc.contributor.author | Grossmann, Siegfried | |
| dc.contributor.author | Lohse, Detlef | |
| dc.date.accessioned | 2019-07-17T18:26:45Z | |
| dc.date.available | 2019-07-17T18:26:45Z | |
| dc.date.issued | 2017-04 | |
| dc.description.abstract | Direct numerical simulations of the Taylor–Couette (TC) problem, the flow between two coaxial and independently rotating cylinders, have been performed. The study focuses on TC flow with mild curvature (small gap) with a radius ratio of n=ri/ro=0.909 , an aspect ratio of r=L/d=2(pie)/3 , and a stationary outer cylinder. Three inner cylinder Reynolds numbers of 1x10^5 , 2x10^5 and 3x10^5 were simulated, corresponding to frictional Reynolds numbers between Rer=1400 and Rer=4000 . An additional case with a large gap, n=0.5 and driving of was also investigated. Small-gap TC was found to be dominated by spatially fixed large-scale structures, known as Taylor rolls (TRs). TRs are attached to the boundary layer, and are active, i.e. they transport angular velocity through Reynolds stresses. An additional simulation was also conducted with inner cylinder Reynolds number of Re=1x10^5 and fixed outer cylinder with an externally imposed axial flow of comparable strength to the wind of the TRs. The axial flow was found to convect the TRs without any weakening effect. For small-gap TC flow, evidence was found for the existence of logarithmic velocity fluctuations, and of an overlap layer, in which the velocity fluctuations collapse in outer units. Profiles consistent with a logarithmic dependence were also found for the angular velocity in large-gap TC flow, albeit in a very reduced range of scales. Finally, the behaviour of both small- and large-gap TC flow was compared to other canonical flows. Small-gap TC flow has similar behaviour in the near-wall region to other canonical flows, while large-gap TC flow displays very different behaviour. | |
| dc.identifier | 10.1017/jfm.2015.675 | |
| dc.identifier.citation | Copyright 2017 Journal of Fluid Mechanics. This is a pre-print version of a published paper that is available at: https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/article/nearwall-region-of-highly-turbulent-taylorcouette-flow/89483704EC67341BBF66130766609CBD. Recommended citation: Ostilla-Mónico, Rodolfo, Roberto Verzicco, Siegfried Grossmann, and Detlef Lohse. "The near-wall region of highly turbulent Taylor–Couette flow." Journal of fluid mechanics 788 (2016): 95-117.doi:10.1017/jfm.2015.675. This item has been deposited in accordance with publisher copyright and licensing terms and with the author's permission. | |
| dc.identifier.uri | https://hdl.handle.net/10657/4127 | |
| dc.language.iso | en_US | |
| dc.publisher | Journal of Fluid Mechanics | |
| dc.subject | Rotating turbulence | |
| dc.subject | Taylor-Couette flow | |
| dc.subject | Furbulent flows | |
| dc.title | The near-wall region of highly turbulent Taylor–Couette flow | |
| dc.type | Article |