Across-wind vibrations of structures of circular cross-section. Part I. Development of a mathematical model for two-dimensional conditions

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Abstract

A model is presented for predicting the across-wind response of constant-diameter circular cylinders vibrating in a mode of uniform amplitude and subject to uniform flow. A key feature of the model is the representation of all motion-dependent phenomena by a nonlinear aerodynamic damping force. This force coexists with the fluctuating force which arises from vortex shedding on a stationary cylinder, and the two forces are assumed to be uncorrelated.

The ability of the device used in representing the motion-induced force to model certain aeroelastic characteristics associated with vibrating cylinders is demonstrated. The device is shown to be capable of successfully reproducing two effects; namely, the increase of the spanwise correlation of forces with increasing amplitude, and the phenomenon of “lock in” where the shedding frequency is apparently dictated by the vibration frequency.

The model is developed within the framework of random-vibration theory, and a number of simplifying assumptions are necessary to incorporate the nonlinear aerodynamic damping force and also to account for the influence of turbulence. Numerical experiments, undertaken to examine the nature of the approximations involved in the assumptions adopted, are described. The results of the numerical experiments are very encouraging and justify the simplifications made in the modelling process.

References (30)

  • J. Vellozi et al.

    Gust response factors

    Am. Soc. Civ. Eng., J. Struct. Div.

    (1968)
  • R.T. Hartlen et al.

    Lift—oscillator model of vortex-induced vibration

    Am. Soc. Civ. Eng., J. Eng. Mech. Div.

    (1970)
  • ESDU

    Across-flow response due to vortex-shedding: isolated circular cylindrical structures in wind or gas flows

    (1978)
  • B.J. Vickery et al.

    Lift or across-wind response of tapered stacks

    Am. Soc. Civ. Eng., J. Struct. Div.

    (1972)
  • T. Sarpkaya

    Vortex-induced oscillations—a selective review

    J. Appl. Mech., Trans. Am. Soc. Mech. Eng.

    (1979)
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