Nonlinear vortex induced vibrations of inclined marine risers

Feras Alfosail, Ali H. Nayfeh, Mohammad Younis

Research output: Contribution to conferencePaperpeer-review

1 Scopus citations


In this paper, we study the nonlinear dynamics of statically deflected offshore structures undergoing vortex induced vibrations. We consider inclined risers that have catenary-like profiles where the riser structure is modelled as an Euler-Bernoulli beam with mid-plane stretching and under self-weight. The statically deflected structure is subjected to vortex induced vibration forces and its equation of motion is coupled with Van der Pol oscillator. Then, we use mode shapes, extracted from the linear eigenvalue problem, in Galerkin method. This reduces the coupled system to a set of nonlinear ordinary differential equations. We use long time integration with Runge-Kutta method to integrate the coupled system and obtain the response while varying the inclination angle, internal velocity, and external velocity. The numerical results reveal the effects of the nonlinearity on the response of the structure, modal interaction, and resonance interactions.

Original languageEnglish (US)
StatePublished - Jan 1 2017
Event24th International Congress on Sound and Vibration, ICSV 2017 - London, United Kingdom
Duration: Jul 23 2017Jul 27 2017


Conference24th International Congress on Sound and Vibration, ICSV 2017
CountryUnited Kingdom


  • Galerkin
  • Inclined risers
  • Vortex induced vibrations

ASJC Scopus subject areas

  • Acoustics and Ultrasonics

Fingerprint Dive into the research topics of 'Nonlinear vortex induced vibrations of inclined marine risers'. Together they form a unique fingerprint.

Cite this