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Analytical and Numerical Studies of Downwash over Rectangular Planforms

Published online by Cambridge University Press:  07 June 2016

H C Garner  and
G F Miller
H C Garner
Affiliation:
Royal Aircraft Establishment, Farnborough
G F Miller
Affiliation:
National Physical Laboratory
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Summary

The paper considers the distribution of downwash at the surface of rectangular planforms with prescribed subsonic aerodynamic loading. Three separate aspects of the problem are treated analytically, the results of each being tested against those derived from an accurate numerical procedure (Section 2). Asymptotic expressions for large and small aspect ratio are formulated and shown to apply over a wide range of aspect ratio (Section 3). Downwash routines from certain existing lifting-surface methods are studied, and their patterns of convergence are illustrated and compared (Section 4). A logarithmic singularity near the leading tip corner is identified, but it is observed that this can exist without serious detriment to the lifting-surface methods (Section 5).

Type
Research Article
Information
Aeronautical Quarterly , Volume 23 , Issue 3 , August 1972 , pp. 169 - 180
Copyright
Copyright © Royal Aeronautical Society. 1972

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References

1. Multhopp, H Methods for calculating the lift distribution of wings. (Subsonic lifting-surface theory). ARC R & M 2884, January 1950.Google Scholar
2. Garner, H C Accuracy of downwash evaluation by Multhopp’s lifting-surface theory. ARC R&M 3431, July 1964.Google Scholar
3. Garner, H C Fox, D A Algol 60 programme for Multhopp’s low-frequency subsonic lifting-surface theory. ARC R & M 3517, April 1966.Google Scholar
4. Zandbergen, P J Labrujere, Th E Wouters, J G A new approach to the numerical solution of the equation of subsonic lifting surface theory. NLR (Amsterdam) Report TR G 49, November 1967.Google Scholar
5. Ray, Valerie A Miller, G F Numerical evaluation of the downwash integral for a lifting rectangular planform. NPL Report Maths 90, December 1970.Google Scholar
6. Miller, G F Asymptotic evaluation of the downwash integral for rectangular planforms of large and small aspect ratio. (To appear as NPL Maths Report).Google Scholar
7. Lehrian, Doris E Garner, H C Convergence of current routines for evaluating downwash at a lifting surface. NPL Aero Note 1095, ARC Report 32 397, September 1970.Google Scholar
8. Hewitt, B L Kellaway, W A new treatment of the subsonic lifting surface problem using curvilinear coordinates. Part I. Details of the method as applied to regular surfaces with finite tip chords and a preliminary set of numerical results. BAC Preston Division Report Ae 290, S & T Memo 20/68, August 1968.Google Scholar
9. Garner, H C Hewitt, B L Labrujere, T E Comparison of three methods for the evaluation of subsonic lifting-surface theory. ARC R&M 3597, June 1968.Google Scholar
10. Kellaway, W Evaluation of the downwash integral for rectangular planforms by the BAC subsonic lifting-surface method. Aeronautical Quarterly, Vol XXIII, p 181 (opposite), August 1972.CrossRefGoogle Scholar
11. Sells, C C L Calculation of the downwash on the centre line of a swept wing with given load distribution. RAE Technical Report 70146, August 1970.Google Scholar