Nonlinear URANS model for evaluating course keeping and turning capabilities of a vessel with propulsion system failure in waves

The loss of ship propulsion has been reported to be the most frequent cause of accidents at sea over the last few years. The loss of propulsive power has a notable effect on the behaviour of a ship during ship manoeuvring, and hence the manoeuvrability of ships suffering from propulsion loss should be accurately estimated for navigation safety. The aim of this study is to evaluate the effects of a propulsion failure on the manoeuvrability of the KRISO Container Ship (KCS) using a fully nonlinear URANS model, which is capable of resolving complex fluid-structure interactions with high accuracy. A series of case studies were carried out to compare the ship performances of both the normal and propulsion loss condition, especially for the course keeping and turning circle manoeuvres. The results explicitly revealed that the propulsion failure has a strong influence on the ship manoeuvrability, implying the importance of sufficient propulsion power when vessels are underway. The key findings obtained from this study are believed to provide navigators with a practical insight into ship manoeuvrability under the propulsion failure condition as well as contribute to developing standards for navigational safety in waves.