A study on interaction among hull, diesel engine and propellers of a twin-screw ship during turning circle maneuver.

• The interaction among hull, engine and propellers of a twin-screw ship during turning circle maneuver is studied. • An ONR tumblehome ship and a PA6 diesel engine are taken as the study objects. • A series of captive model tests are simulated by using CFD method to establish the MMG model of ship maneuvering motion. • The quasi-steady model of the engine is incorporated with the MMG model to build a simulation system. • The hull-engine-propeller interaction and engine operating characteristics during turning circle maneuvers are evaluated. A marine propulsion plant will experience power fluctuations during ship maneuvers. In the turning circle maneuver, the propulsive load increases significantly, and the power required by the two shafts of a twin-screw ship may be completely inconsistent. To protect the propulsion plant, the interaction between the engine and the propellers should be studied in depth. In this paper, the twin-screw ONRT ship and the 16PA6-STC diesel engine are selected as the study objects. A series of captive model tests are simulated by using CFD method to obtain the hydrodynamic derivatives and hull-propeller-rudder interaction coefficients in the MMG model. The effective wake fraction is computed under the maneuvering conditions. Turning circle maneuver of the ship is predicted by using the established MMG model, and the predicted ship maneuvering characteristics show good agreement with the available experimental results, which verifies the CFD-based modeling method. Finally, a dynamic model of hull-engine-propeller system is established on the simulation platform for evaluating the operating characteristics of propulsion plant. The propeller loads are predicted and the interaction among hull, engine and propellers is investigated. This study helps to provide a deeper insight into the engine operation behaviors during turning circle maneuver of a ship. [ABSTRACT FROM AUTHOR]