Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-28T07:03:27.814Z Has data issue: false hasContentIssue false
  • English
  • Français

A Theoretical Calibration Curve for the Preston Tube on Smooth Boundaries for Larger Reynolds Numbers

Published online by Cambridge University Press:  04 July 2016

N. Rajaratnam
N. Rajaratnam*
Affiliation:
Department of Civil Engineering, University of Alberta, Canada
Get access Rights & Permissions [Opens in a new window]

Extract

Of the Several Methods available for the measurement of boundary shear, the simplest is perhaps the Preston tube. It is a total head tube resting on the boundary for which the difference between the dynamic pressure on the tube and the static pressure on the boundary is correlated with the boundary shear. It was evolved by Preston in 1954 mainly from similarity considerations and the existence of the wall law. In 1955, Hsu obtained Preston's original calibration curve theoretically for the one-seventh power law. In this note, a theoretical calibration curve is developed for the logarithmic law which describes the velocity distribution for larger Reynolds Numbers.

Type
Technical Notes
Information
The Aeronautical Journal , Volume 69 , Issue 650 , February 1965 , pp. 136 - 137
Copyright
Copyright © Royal Aeronautical Society 1965

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

1.Preston, J. H.The Determination of Turbulent Skin Friction by Means of Pitot Tubes. Journal of the Royal Aeronautical Society, Vol. 58, 1954.Google Scholar
2.Hsu, E. Y. The Measurement of Local Turbulent Skin Friction by Means of Surface Tubes. D.W.T. Model Basin. Rep. 957, 1955.Google Scholar
3.Rosenhead, L.Laminar Boundary Layers, Chapter X. Oxford, 1963.Google Scholar
4.Hwanh, L. S. and Laursen, E. M. Shear Measurement Technique for Rough Surfaces. Proc. A.S.C.E., J. Hyd. Div., March 1963.Google Scholar
5.Granville, P. S. The Determination of Local Skin Friction and the Thickness of Turbulent Boundary Layers from the Velocity Similarity Laws. D.W.T. Model Basin Rep. 1340, 1959.Google Scholar
6.Smith, D. W. and Walker, J. H. Skin Friction Measurements in Incompressible Flow. NACA TN 4231, 1958.Google Scholar
7.Rechenberg, I. Messung der Turbulenten Wandschubspannung, Zeitschrift fur Flugwissenschaften, 11, Heft 11, 1963. This reference gives an extensive bibliography on the Preston tube.Google Scholar