Unformatted text preview: + S c d ) which is a suitable alternative objective function. The ±gure shows the isolines of V max versus the design variables, calculated using (1). The slight upturn in the isolines for decreasing AR is the Re eﬀect in c d . The sharp downturn near AR = 0 is due to the induced drag term. Isolines computed using the approximation (2) would be level. Now the stiﬀnessconstrained optimum results in an unreasonably small wing, which means that other more practical constraints are likely to come into play. AR S 8 16 24 6 12 18 V max V max = 10 V max = 14 = 12 b b b δ/ = 0.2 δ/ = 0.05 δ/ = 0.01 V max = 16 Figure 1: Objective function contours (isolines) in design space of a rectangular wing. Dot shows the stiﬀnessconstrained optimum point. 1...
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 Fall '05
 MarkDrela
 Optimization, vmax, ηp ηm Pmax, ηm Pmax

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