Abstract
In this paper, the hydrodynamic forces and vortex distributions of a riser subjected to a non-uniform flow generated by an upstream oscillating wing structure are simulated using high-precision code Incompact3d combined with immersed boundary method. The effects of in-line and transverse positions, oscillating frequency and amplitude on riser performance have also been discussed. It is found that with the increase of in-line spacing or the decrease of oscillation frequency and transverse positions, the time-averaged drag coefficient of riser changes from the negative values to positive values. The time-averaged lift coefficient of riser is generally insensitive to oscillation frequency. However, it shows a large shift when changing the transverse positions or the amplitude of the wing is larger than π/6. Moreover, for various in-line positions, oscillating frequency and amplitude, the vortex shedding of the rigid riser, indicated by the main frequency of lift force, is always locked by the oscillating wing. However, when the transverse position is changing, the ratio of main frequency of lift coefficient to the swing frequency does not still remain 1:1. More concretely, the maximum time-averaged drag coefficient and lift coefficient Root-mean-square value of 0.559 and 1.629 is obtained in the simulation respectively.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
