• 제목/요약/키워드: Operability envelope

검색결과 1건 처리시간 0.014초

Nonlinear self-induced vibration and operability envelope analysis of production strings in marine natural gas development

  • Liu, Kang;Chen, Guoming;Zhu, Gaogeng;Zhu, Jingyu
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제11권1호
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    • pp.344-352
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    • 2019
  • Marine production strings are continuously affected by unstable internal fluid during operation. In this paper, the structural governing equation for marine production string self-induced vibration is constructed. A finite element analysis model is established based on Euler-Bernoulli theory and solved by the Newmark method. Furthermore, based on reliability theory, a self-design procedure is developed to determine the operability envelope for marine production string self-induced vibration. Case studies show: the response frequency of the production strings is consistent with the excitation frequency under harmonic fluctuation and mainly determined by the first-order natural frequency under stochastic fluctuation. The operability envelope for marine production string self-induced vibration is a near symmetrical trapezium. With the increasing of natural gas output, the permissible fluctuation coefficient dramatically decreases. A reasonable centralizer spacing, increasing top tension, and controlling natural gas output are of great significance to the risk control in marine production string operation.