Roughness effects in turbulent pipe flow

M. A. Shockling, J. J. Allen, A. J. Smits

Research output: Contribution to journalArticle

148 Scopus citations

Abstract

Mean flow measurements are presented for fully developed turbulent pipe flow over a Reynolds number range of 57 × 103 to 21 × 106 where the flow exhibits hydraulically smooth, transitionally rough, and fully rough behaviours. The surface of the pipe was prepared with a honing tool, typical of many engineering applications, achieving a ratio of characteristic roughness height to pipe diameter of 1 : 17000. Results for the friction factor show that in the transitionally rough regime this surface follows a Nikuradse (1933)-type inflectional relationship rather than the monotonic Colebrook (1939) relationship used in the Moody diagram. This result supports previous suggestions that the Moody diagram in the transitional regime must be used with caution. Outer scaling of the mean velocity data shows excellent collapse and strong evidence for Townsend's outer layer similarity hypothesis for rough-walled flows. Finally, the pipe exhibited smooth behaviour for scaled roughness height ks+ ≤ 3.5, which supports the suggestion by Zagarola & Smits (1998) that their pipe was hydraulically smooth for ReD ≤ 24 × 106.

Original languageEnglish (US)
Pages (from-to)267-285
Number of pages19
JournalJournal of Fluid Mechanics
Volume564
DOIs
StatePublished - Oct 10 2006

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Fingerprint Dive into the research topics of 'Roughness effects in turbulent pipe flow'. Together they form a unique fingerprint.

  • Cite this

    Shockling, M. A., Allen, J. J., & Smits, A. J. (2006). Roughness effects in turbulent pipe flow. Journal of Fluid Mechanics, 564, 267-285. https://doi.org/10.1017/S0022112006001467