Page 44 - Fluid-Structure Interactions Slender Structure and Axial Flow (Volume 1)
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CONCEPTS, DEFINITIONS AND METHODS                     27









































        Figure 2.5  (a) A slender body of revolution in uniform flow at a small angle of attack, a. (b) A
        flexible slender body  performing  lateral  oscillations of  long wavelength, such that each segment
                may  be considered to be part of an infinitely long cylinder; a = tan-'(&/&).

        and
                                    V4 = 0    at infinity.                   (2.77b)

        If the angle of attack is a, then in the (r, 8, x)-frame equations (2.77a,b) lead to (Karam-
        cheti 1966)
                             aF                 aF
          (V,  sin a sin 8 + ur)-  + (V,  cos a + ux)-   = 0   on   F(r, 6, x) = 0  (2.78)
                             ar                 ax

        and
                                ur = ue = u,  = 0   at infinity,              (2.79)

        in which ur, ug  and u,  are the components of V4, and aF/ar = 1, aF/ax = -dR/dx  from
        (2.74). Hence, the surface condition (2.78) becomes
                                       dR
                                                                     L.
                      = (V,  cos a + ux)-  - V,  sin a sin 8,   0 I I         (2.80)
                                                                 x
                   r=R                 dx
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