Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-27T11:39:10.048Z Has data issue: false hasContentIssue false
  • English
  • Français

Direct measurements of skin friction in a turbulent boundary layer with a strong adverse pressure gradient

Published online by Cambridge University Press:  19 April 2006

D. Frei  and
H. Thomann
D. Frei
Affiliation:
Institute of Aerodynamics, Swiss Federal Institute of Technology, Zurich
H. Thomann
Affiliation:
Institute of Aerodynamics, Swiss Federal Institute of Technology, Zurich
Get access Rights & Permissions [Opens in a new window]

Abstract

This paper describes a new balance, suitable for direct measurement of skin friction in turbulent boundary layers with severe pressure gradients. The gaps between the floating element and the surrounding wall are filled with a liquid in order to eliminate disturbing pressure forces on the element. The resulting friction forces are measured with piezo-electric transducers with high sensitivity and extremely small element displacement.

Skin friction measurements were taken in the turbulent boundary layer of a wind tunnel with circular cross-section at M [les ] 0·25. Severe adverse pressure gradients were generated by means of a step on the wall or, alternatively, by a conical centre body.

The new apparatus was mainly used to investigate the error of Preston tubes in adverse pressure gradients. It was necessary to develop a new measuring technique to improve the repeatability of the Preston tube readings.

The Preston tube error was found to depend on both the local pressure gradient P = (dp/dx) ν/ρ3τ and on the Preston tube diameter uτd/ν and to be independent of the upstream pressure distribution for the range of parameters covered by the experiments.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 101 , Issue 1 , 13 November 1980 , pp. 79 - 95
Copyright
© 1980 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

Bertelrud, A. 1972 Skin friction measurement technique in incompressible turbulent flow, a literature survey. Aero. Res. Inst., Sweden, Tech. Note AU-726.Google Scholar
Brown, K. C. & Joubert, P. N. 1969 The measurement of skin friction in turbulent boundary layers with adverse pressure gradients. J. Fluid Mech. 35, 737–757.Google Scholar
Coles, D. E. & Hirst, E. A. 1968 Computation of turbulent boundary layers. 1968 AFOSR-IFP-Stanford Conf. vol. II.
Frei, D. 1979 Direkte Wandschubspannungsmessung in der turbulenten Grenzschicht mit positivem Druckgradient. Diss. ETH Nr. 6392.Google Scholar
Patel, V. C. 1965 Calibration of the Preston tube and limitation on its use in pressure gradients. J. Fluid Mech. 23, 185–208.Google Scholar
Philips, 1976 Piezo ceramics, permanent magnet materials. Philips Data Handbook, part 4b, 37–39.Google Scholar
Pozzorini, R. 1976 Das turbulente Strömungsfeld in einem langen Kreiskegel-Diffusor. Diss. ETH Nr. 5646.Google Scholar
Preston, J. H. 1954 The determination of turbulent skin friction by means of Pitot tubes. J. Roy. Aero. Soc. 58, 109–121.Google Scholar
Rechenberg, I. 1963 Messung der turbulenten Wandschnbspannung. Z. Flugwiss. 11, 429–438.Google Scholar
Reeder, T. M. & Cullen, D. E. 1976 Surface-acoustic-wave pressure and temperature sensors. Proc. I.E.E.E. 64, 754–756.Google Scholar
Schultz-Grunow, F. 1940 Neues Riebungswiderstandsgesetz für glatte Platten. Luftfahrtforschung 17 (8), 239.Google Scholar
Tomm, D. 1978 Bestimmung der stationären und instationären Wandschubspannung mit Laser-Doppler-Anemometrie. Abhandl. Aerodyn. Inst. TH Aachen 23.Google Scholar
Winter, K. G. 1977 An outline of the techniques available for the measuring of skin friction in turbulent boundary layers. Prog. Aerospace Sci. 18, 1–57.Google Scholar