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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
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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

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References

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