Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-24T22:45:36.305Z Has data issue: false hasContentIssue false
  • English
  • Français

Viscous Effects on Pitot Tubes at Low Speeds

Published online by Cambridge University Press:  28 July 2016

F. A. Macmillan
F. A. Macmillan*
Affiliation:
Engineering Laboratory, Cambridge
Get access Rights & Permissions [Opens in a new window]

Extract

Measurements were made of the pressure in a blunt-nosed pitot tube, in an air stream at Reynolds numbers from about 15 to 1,000. The results are expressed in terms of a pressure coefficient , where P is the pressure in the pitot tube, ρ is the density of the fluid, and p and V are the static pressure and velocity in the undisturbed stream. As found in previous investigations, Cp becomes greater than 1 at low Reynolds numbers, the increase being about per cent, at a Reynolds number of 50 (based on external tube radius). In disagreement with the work of Hurd, Chesky, and Shapiro, no decrease of Cp below 1 was found at any Reynolds number.

Type
Technical Notes
Information
The Aeronautical Journal , Volume 58 , Issue 524 , August 1954 , pp. 570 - 572
Copyright
Copyright © Royal Aeronautical Society 1954

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. Hurd, C. W., Chesky, K. P. and Shapiro, A. H. (1953). Influence of Viscous Effects on Impact Tubes. Journal of Applied Mechanics, Vol. 20, No. 2, pp. 253–256, 1953.Google Scholar
2. Durand, W. F. (1935). Aerodynamic Theory, Vol. III, pp. 69–75.Google Scholar
3. Homann, F. (1952). The Effect of High Viscosity on the Flow Around a Cylinder and Around a Sphere. N.A.C.A. T.M. No. 1334, 1952.Google Scholar
4. Barker, M. (1922). On the Use of Very Small Pitot-Tubes for Measuring Wind Velocity. Proc. Roy. Soc, A, Vol. 101, pp. 435–445, 1922.Google Scholar
5. Homann, F. (1936). Einfluss grosser Zahigkeit bei Stromung um Zylinder. Forschung auf dem Gebiete des Ingenieurwesens, Vol. 7, pp. 1–10, 1936.Google Scholar
6. Sherman, F. S. (1953). New Experiments on Impact-Pressure Interpretation in Supersonic and Subsonic Rarefied Air Streams. N.A.C.A. T.N. No. 2995, 1953.Google Scholar
7. Macmillan, F. A. (1954). Liquid Manometers with High Sensitivity and Small Time-Lag. Journal of Scientific Instruments, Vol. 31, No. 1, pp. 17–20, 1954.CrossRefGoogle Scholar
8. Preston, J. H. (1950). The Three-Quarter Radius Pitot Tube Flow Meter. The Engineer, Vol. 190, pp. 400–402, 1950.Google Scholar