Study on the Effect of Climate Change on Ship Responses Based on Nonlinear Simulations
Hull girder ultimate strength governs sagging and hogging failures, which is one of the most critical failure modes for a ship hull. The structural reliability analysis methodology has been used to develop common structural rules for tankers and bulk carriers. A linear model for bending moment in extreme weather with a nonlinear correction factor has been adopted in the analysis. It is difficult to conclude on the model uncertainty associated with nonlinear effects of bending moment as, until now, there are few studies addressing this topic. In this paper, the nonlinear effect on ship responses is analyzed, and the potential effect of climate change on ship responses is investigated with the improved three-dimensional (3D) Rankine Panel method using nonlinear wave input. The nonlinear wave input is generated by the higher-order spectral method (HOSM) wave model incorporating higher-order nonlinear effects, including nonlinear free-wave modulation as well as higher-order bound harmonics. The past and projected future wave climates of selected locations in the North Atlantic and North Norwegian Sea are considered.