The classical calculation of inviscid drag, based on far-field flow properties, is re-examined with particular attention to the nonlinear effects of wake roll-up. Based on a detailed look at nonlinear, inviscid flow theory, the paper concludes that many of the classical, linear results are more general than might have been expected. Departures from the linear theory are identified and design implications are discussed. Results include the following: Wake deformation has little effect on the induced drag of a single element wing, but introduces first order corrections to the induced drag of a multi-element lifting system. Far-field Trefftz-plane analysis may be used to estimate the induced drag of lifting systems, even when wake roll-up is considered, but numerical difficulties arise. The implications of several other approximations made in lifting line theory are evaluated by comparison with more refined analyses.
The Computation of Induced Drag with Nonplanar and Deformed Wakes
Sae Technical Papers
Aerospace Technology Conference and Exposition ; 1990
1990-09-01
Aufsatz (Konferenz)
Englisch
Improved Computation of Induced Drag for Wakes of Arbitrary Shape
British Library Conference Proceedings | 2013
|Minimum Induced Drag of Nonplanar Wings
NTRS | 1983
|Induced Drag Computations on Wings with Accurately Modeled Wakes
Online Contents | 1997
|