English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Characterizing the turbulent drag properties of rough surfaces with a Taylor–Couette set-up

Berghout, P., Bullee, P. A., Fuchs, T., Scharnowski, S., Kähler, C. J., Chung, D., et al. (2021). Characterizing the turbulent drag properties of rough surfaces with a Taylor–Couette set-up. Journal of Fluid Mechanics, 919: A45. doi:10.1017/jfm.2021.413.

Item is

Basic

show hide
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Berghout, Pieter1, Author
Bullee, Pim A.1, Author
Fuchs, Thomas1, Author
Scharnowski, Sven1, Author
Kähler, Christian J.1, Author
Chung, Daniel1, Author
Lohse, Detlef2, Author              
Huisman, Sander G.1, Author
Affiliations:
1External Organizations, ou_persistent22              
2Max Planck Institute for Dynamics and Self-Organization, Max Planck Society, ou_2063285              

Content

show
hide
Free keywords: -
 Abstract: Wall roughness induces extra drag in wall-bounded turbulent flows. Mapping any given roughness geometry to its fluid dynamic behaviour has been hampered by the lack of accurate and direct measurements of skin-friction drag. Here, the Taylor–Couette (TC) system provides an opportunity as it is a closed system and allows direct and reliable measurement of the skin-friction. However, the wall curvature potentially complicates the connection between the wall friction and the wall roughness. Here, we investigate a highly turbulent TC flow, with a hydrodynamically fully rough, rotating inner cylinder, while the outer cylinder is kept smooth and stationary. We carry out particle image velocimetry (PIV) measurements in the Twente Turbulent Taylor–Couette (T3C) facility with Reynolds numbers in the range of 4.6×105<Rei<1.77×106. From these we find, while taking into account the influence of the curved walls on the turbulence, that the observed effects of a hydrodynamically fully rough surface are similar for TC turbulence and flat-plate turbulent boundary layer flows (BL). Hence, the equivalent sand grain height ks, that characterizes the drag properties of a rough surface, is similar for both flow geometries. Next, we obtain the dependence of the torque (skin-friction drag) on the Reynolds number for a given wall roughness, characterized by ks, and find agreement with the same results derived from PIV measurements within 5%. Our findings demonstrate that global torque measurements in the TC facility could be well suited to reliably deduce wall-drag properties for any rough surface.

Details

show
hide
Language(s): eng - English
 Dates: 2021-06-012021
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: -
 Identifiers: DOI: 10.1017/jfm.2021.413
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Journal of Fluid Mechanics
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: -
Pages: 21 Volume / Issue: 919 Sequence Number: A45 Start / End Page: - Identifier: ISSN: 0022-1120
ISSN: 1469-7645