Nonlinear computational methods for hydroelastic effects of ships in extreme seas

We present computational methods to assess slamming-induced hull whipping on sectional loads of ships in regular and irregular waves. The numerical methods solved the Reynolds-averaged Navier-Stokes (RANS) equations coupled with the nonlinear rigid body motion equations of the elastic ship hull. We numerically investigated three containerships in regular waves, in random irregular long crested waves, and in deterministic wave sequences. Comparisons to experimental measurements agreed favorably. We relied on different wave models, including second order Stokes waves and nonlinear wave fields obtained from the solution of nonlinear Schrodinger equations (NLS). Simulations in random irregular waves provided short-term ship response probability distributions under sea state conditions relevant for design loads.