| Maneuverability is one of the most important hydrodynamic performances of ships. It is of great significance to carry out prediction of ship maneuvering hydrodynamic forces and to improve the prediction accuracy. During the last dacade, the CFD-based numerical prediction method is more and more widely used and has become as important as captive model tests in predicting ship maneuvering hydrodynamic forces.In this thesis, a numerical method based on solving the RANS equations is adopted to simulate the viscous flow around an appended ship moving in simple maneuvering manner such as oblique motion and stread-ahead with different rudder angles. The turbulence is modeled by the RNG k-ε model and the rotating propeller is simulated with sliding mesh technique. The numerical method is applied to simulate the flow around the hull-rudder system and hull-propeller-rudder system moving in oblique motion or straight-ahead with different rudder angles, and the detailed flow field around the hull-rudder system is illustrated. The influence of propeller on flow field is analyzed by comparing the numerical results with and without propeller. Meanwhile, based on the results of hull-propeller-rudder system in straight-ahead conditions with different rudder angles, the coefficients of hydrodynamic interactions among hull, propeller and rudder are determined.The numerical method adopted in this thesis can properly simulate the viscous flow around a full-appended ship in maneuvering motion. The conclusions about the hydrodynamic mechanisms of hull-rudder system in maneuvering conditions and the effect of the propeller on the hydrodynamic forces have a certain reference values for predicting the hydrodynamic forces of a hull-propeller-rudder system in maneuvering motion. In addition, the CFD-based analyzing method utilized in this thesis in study of hydrodynamic interaction among hull-propeller-rudder may be of some practical value in studies of MMG modeling. |
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