Modeling And Simulation Of Ship's Motion In Propeller Reversing

In order to predict the motion of the ship for operators, and decrease or avoid disasters, the research works about ship's motion in restricted water as propeller reversing are very important. However there is a lack of a satisfying model for simulation and prediction of ship's crash stopping and backing by far. This article tries to suggest a model of this kind.Firstly, the ship must go through stopping and backing processes with propeller reversing, so this article provide a math model which combined the Kijima model and Yoshimura model. The mixed model was suitable for the entire maneuvering range including normal speed, low speed, small and large drift angle and so on. Considering the effect of shallow water, the conclusions researched by Kijima was adopted.Secondly, with regard to calculation of thrust and torque coefficients of screw propeller in four-quadrant, a realization method based on MATLAB is established. And then the above mentioned coefficients can be calculated directly by computer according to screw principal particulars. Concerning the screw side-forces, a theoretical calculation was suggested and the results were applied to the last simulations.Finally, in order to prove the model suggested by this article was correct and effective, the realistic simulations which include turning ability, stopping ability and backing ability were made. Among the simulations the effects of wind, current and shallow water were taken into account for the sake of reality. The results were satisfactory by comparing with ship trails and testify the correction and validation of the model, and this model can be used for calculation and prediction of ship's maneuverability.