| In this paper, by numerical simulating viscous flow field of a river-sea container ship, viscous details including flow characteristic, viscous resistance and its components, and wake distribution behind ship stern were obtained.This river-sea ship belongs to low-speed full form. When it sailing on low speed, the principal component of wake is the frictional wake, next is the potential wake, and wave wake is very small, which can be ignored. With full hull, big wet surface area and low Froude number, viscous resistance of this kind of ships is so big that it is the primary factor affecting ship's rapidity. Therefore numerical simulating viscous flow field has significance to rapidity of this form.There are mainly three methods to solve this problem at present: model test, interpolation and calculating fluid dynamics. CFD method has the following merit: it do not need special test equipment, device and series model test which wastes much time; flow details can be obtained ; excellent ship form can be developed by revising the ship type, analyzing its hydromechanics by CFD; and CFD can be used on full scale ship to avoid "scale effect" influence.Supported from high-effect CFD method, it is hopeful to solve the marine hydromechanics without tests in tank. Some CFD commercial software is developed in order to combine CFD study and its application to project. Adopting the ready made commerce software is a good way to solve hydromechanics problems.The thesis used GAMBIT for preprocessing to form calculation model and mesh the calculation zone, then RANS Equations was solved by FLUENT and viscous flow of the 200TEU was obtained. At last, result of numerical simulation was checked up by the tank tests.The tests show that viscous resistance and wake distribution got from numerical simulation are satisfied. Viscous flow details such as flow line separation and pre-whirl at propeller plan was also obtained which could do help for improvement of the ship line.
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