Application of CFD-FEA coupling to predict hydroelastic responses of a single module VLFS in extreme wave conditions

Freak waves, as a kind of strong nonlinear waves, have a great threat to the safety of Very Large Floating Structures (VLFS). Freak wave produces enormous wave height, which caused the hydroelastic responses on the VLFS to increase significantly. Nevertheless, due to the complexity of the highly nonlinear interactions between waves and VLFS, studies of wave-induced loads and the hydroelastic responses of VFLS in freak waves are rare. In this paper, a fluid-structure interaction technique that strongly connects the CFD and FEA solvers is proposed to evaluate the wave-induced loads and hydroelastic responses of a single module VLFS under freak wave cir-cumstances. The accuracy and reliability of the CFD-FEA coupling approach is validated through the compari-sons of the results of hydroelastic responses of VLFS in regular waves with those from other numerical methods. Finally, the global motion and vertical bending moment (VBM) of VLFS in freak wave conditions are investi-gated. The result shows that the freak wave will lead to the global motion of VLFS being multiplied several times and largely increasing the instantaneous maximum VBM. The novel findings in this study will provide a reference for the structural design of VLFS under survival conditions.

Automated summary

In this paper, a fluid-structure interaction technique is proposed to evaluate the wave-induced loads and hydroelastic responses of a single module VLFS under freak wave circumstances. The accuracy and reliability of the approach are validated through comparisons with other numerical methods. The study reveals that freak waves can cause significant increase in the global motion and vertical bending moment of VLFS, providing valuable insights for the structural design of VLFS under survival conditions.