Extending the numerical ship maneuvering models in irregular long-crested waves to low-speed applications

This paper extends a time-domain, 6-DOF direct superposition numerical framework for ship maneuvering in waves to the less-explored low-speed regime. The model couples a Maneuvering Modelling Group (MMG) calm-water formulation with a blended non-linear seakeeping model. Validated against experimental data for the KVLCC2 tanker, the framework is tested through turning-circle simulations in irregular long-crested seas and low-speed course-keeping simulations across various wave headings. The results demonstrate that the direct superposition approach provides reliable predictions for control purposes in waves, even under reduced maneuvering capabilities. Moreover, the study reveals that once the calm-water model is calibrated, the framework maintains a consistent level of accuracy across different speed regimes, proven here for low-speed conditions.