Author:
Chen Jin,Chen Min,Liu Mingyue
Abstract
Abstract
This paper presents the CFD investigation of the vortex induced motion (VIM) of a caisson model during the installation process. The simulations were performed by solving the unsteady 3D Navier-Stokes equation. The Dynamic Fluid-Body Interaction (DFBI) tool is utilized to simulate the motions. Typical draft conditions of a caisson during installation process are considered. The present methodology is verified through the free decay and the VIM of a cylinder simulations in two-dimension. Free decay simulations show that the natural frequency decrease with the increasing draft of the caisson. Maximum response amplitudes occur in the range of 10<Vr
<13 for the draft Dp=0.1m. The resonance occurs when the crossflow response frequency f
y is very close to the natural frequency f
n. The inline/crossflow response frequency increases as the draft increases at the same reduced velocity V
r. The response frequency in the inline direction is double of that in the crossflow direction. Eight-shaped trajectories are observed. The maximum displacements in the crossflow direction increase as the drafts increase.
Subject
Computer Science Applications,History,Education
Reference13 articles.
1. The effect of mooring system and sheared currents on vortex induced motions of truss spars;Van Dijk;Proc. of the ASME 22nd Int. Conf. on Offshore Mechanics and Arctic Engineering (813 June, Cancun),2003
2. An overview of relevant aspects on VIM of spar and monocolumn platforms;Gonçalves;J. Energy Resour. Technol.,2012
3. Two-degree-of-freedom vortex-induced vibration of circular cylinders with very low aspect ratio and small mass ratio;Gonçalves;J. Fluids Struct.,2013
4. Experimental investigation of vortex-induced vibration in one and two dimensions with variable mass, damping, and Reynolds number ASME;Blevins;J. Fluids Eng.,2009
5. Study on vortex-induced motions of a new type of deep draft multi-columns FDPSO;Gu;China Ocean Eng.,2018