A Unified Numerical Method for Broaching and Loss of Stability in Astern Seas

The interim guidelines of second-generation intact stability criteria and their explanatory note were issued by the IMO in 2022. However, due to complexity, direct assessments broaching loss still need be made easier for users. Therefore, mathematical models astern seas are studied this paper. Firstly, a time-domain 6 DOF numerical model is adopted, combining seakeeping maneuvering models. Secondly, hydrodynamic forces, heave, pitch motions obtained an enhanced strip method with upright hull at different speeds frequency domain. Then, values transferred from frequency-domain speed variation considered. Thirdly, varied wet waves captured ship motion. Froude–Krylov hydrostatic forces surging, swaying, rolling, yawing directions simulated considering wave pressure around hull. Fourthly, exposure twin rudders wave-particle velocity considered predicting broaching. Finally, calculated results compared published results. show that coupled can unified seas.