Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-18T18:40:18.748Z Has data issue: false hasContentIssue false

The Preston tube as a means of measuring skin friction

Published online by Cambridge University Press:  28 March 2006

M. R. Head
Affiliation:
Department of Engineering, University of Cambridge
I. Rechenberg
Affiliation:
Department of Engineering, University of Cambridge

Abstract

Preston's method of measuring skin friction, which makes use of a Pitot tube resting on the surface, depends upon the assumption of a region of flow similarity, adjacent to the wall, common to fully developed turbulent pipe flow and the turbulent boundary layer. Experiments performed elsewhere have cast considerable doubt on the validity of this assumption, and the present investigation was undertaken to establish whether or not it is justified.

Experiments were carried out in a short length of large-diameter pipe which could either form part of a very much longer pipe, giving fully developed turbulent pipe flow, or could be preceded by a conventional contraction and screens, giving a developing turbulent boundary layer.

Final results showed that for a given skin friction the Pitot tube reading was the same for both boundary layer and pipe flows, thus vindicating Preston's method and confirming the existence of a universal region of wall similarity. Initial experimental difficulties were found to be due to unexpectedly large circumferential variations in skin friction in the growing boundary layer.

Type
Research Article
Copyright
© 1962 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Dutton, R. A. 1956 The accuracy of the measurement of turbulent skin friction by means of surface pitot-tubes and the distribution of skin friction on a flat plate. Aero. Res. Counc., Lond., Rep. & Mem. no. 3058.Google Scholar
Hsu, E. Y. 1955 The measurement of local turbulent skin friction by means of surface tubes. David W. Taylor Model Basin Rep. no. 957.Google Scholar
Konstantinov, N. I. & Dragnysh, G. I. 1960 The measurement of friction stress on a surface. (Trans.) D.S.I.R. RTS 1499.
Landweber, L. 1960 Reanalysis of boundary-layer data on a flat plate. Written discussion for Ninth International Towing Tank Conference, Paris, 1960. Iowa Institute of Hydraulic Research, State University of Iowa.
Ludwieg, H. & Tillmann, W. 1950 Investigations of the wall shearing stress in turbulent boundary layers. (Trans.) Nat. Adv. Comm. Aero., Wash., Tech. Mem. no. 1285.Google Scholar
Maltby, R. L. & Keating, R. F. A. 1960 Flow visualization in low-speed wind tunnels: Current British practice. Aero. Res. Counc., Lond., Rep. no. 22, 373.Google Scholar
Preston, J. H. 1954 The determination of turbulent skin friction by means of pitot tubes. J. Roy. Aero. Soc. 58, 109.Google Scholar
Schubauer, G. B. 1957 Mechanism of transition at subsonic speeds. I.U.T.A.M. Symposium, Freiburg/BR (Published by Springer-Verlag, Berlin, 1958).Google Scholar
Smith, D. S. & Walker, J. H. 1958 Skin friction measurements in incompressible flow. Nat. Adv. Comm. Aero., Wash., Tech. Note no. 4231.Google Scholar
STAFF OF THE AERODYNAMICS DIVISION, N.P.L. 1958 On the measurements of local surface friction on a flat plate by means of Preston tubes. Aero. Res. Counc., Lond., Rep. & Mem. no. 3185.