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3.3.3: Lift and induced drag in wings

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    In order to represent the lift curve, a dimensionless coefficient (\(C_L\)) will be used. \(C_L\) is defined as:

    \[C_L = \dfrac{L}{\tfrac{1}{2} \rho_{\infty} u_{\infty}^2 S_w},\]

    which can also be expressed as:

    \[C_L = \dfrac{L}{\tfrac{1}{2} \rho_{\infty} u_{\infty}^2 S_w} = {1}{\tfrac{1}{2} \rho_{\infty} u_{\infty}^2 S_w} \int_{-b/2}^{b/2} \dfrac{1}{2} \rho_{\infty} u_{\infty}^2 c(y) c_l (y) dy = \dfrac{1}{S_w} \int_{-b/2}^{b/2} c(y) c_l (y) dy.\]

    截屏2022-01-15 下午3.16.48.png
    Figure 3.24: Induced drag.

    Another consequence of the induced velocity is the appearance of a new component of drag (see Figure 3.24), the induced drag. This occurs because the lift is perpendicular to the effective velocity and therefore it has a component in the direction of the freestream (the direction used to measure the aerodynamic drag).

    3.3.3: Lift and induced drag in wings is shared under a CC BY-SA 3.0 license and was authored, remixed, and/or curated by Manuel Soler Arnedo via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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