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Some Simple Results for Two-Dimensional Jet-Flap Aerofoils

Published online by Cambridge University Press:  07 June 2016

D. A. Spence*
Affiliation:
Royal Aircraft Establishment, Farnborough
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Summary

It is shown from elementary considerations that the lift coefficient of a thin two-dimensional wing at zero incidence, with a narrow high-velocity jet of momentum coefficient Cj issuing from its trailing edge at a (small) downward inclination τ, is given by

and the loading on the chord line (0<x<1) by

(except in a certain neighbourhood of the trailing edge), for small values of Cj. These formulae agree well with known measurements. Interpolation formulae for derivatives of CL at larger values of CJ based on earlier work, are also given:

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society. 1958

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References

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