Study On Motion Response Of Broken Ships In Regular Oblique Waves

In recent research, the study on large-amplitude ship motions has been an important theme in the field of ship hydrodynamics. Though there are kinds of nonlinear theory to work with large-amplitude intact ship motions, we still have to develop a theory of ship motions about broken ships.At first this article studies deep into the motions of intact ship condition, and discusses on damaged condition after series of reasonable predigestion. Then, after the studies of the change of hydrodynamic coefficients as a result of the ship broken condition, we presents a nonlinear time-domain simulation method for the prediction of large-amplitude ship motions in regular oblique waves. The velocity potentials of each ship section plane are worked out with two-dimentional Green's function method based on strip theory, so that the hydrodynamic coefficient of the sections can be educed. And then, the added mass, damping coefficients, and wave-exciting forces at each time-step can be calculated by integration of the sectional values over the wetted ship length. When founding the ship motions equations, we have to calculate the effect of floodwater'velocity and weight, and analyse the differdnt impacts produced by the change of the position of the crevasse.At last, concrete calculates are operated to a real broken ship to study its motion responses. Both time-domain and frequency-domain analysis are given in broken condition.