Research On Fast Time-domain Simulation Of Flooding Process And Motions Of A Damaged Ship With Liquid Cargo Tank

Ship will get damaged due to collision and grounding when sailing on the ocean,which may put the crew in danger and take great economic looses,especially when there is liquid cargo or fuel oil on the damaged ship, the environment of the ocean will be severely polluted.A fast time domain simulation method of the flooding process of the oil and the water inside the compartments and the motions .of the body after ship with liquid cargo or fuel oil tank damaged was presented in this paper. The pressure-correction method, which can simulate the flooding process to the empty and complex compartments, was extended to simulate the flooding process to the compartments in which may contain liquid cargo or fuel oil. Up-down and left-right two-compartment structures were respectively calculated, the results of which matched very well with the experimental datas. Besides, the fast extended method was also validated by comparing to the FLUENT results after calculating a damaged left-right two-compartment model with oil tank, and it cost only 1/4200 times of the software did. Then two methods were used method to calculate the motions of the damaged ship during the flooding process, one was to solve the the mechanics equilibrium equation of the damaged ship floatation based on the quasi-static method in every moment of the flooding process,the other one was to solve the three degree-of-freedom defferential equation of motions of the damaged ship in calm sea of in waves.With the combination of the extended pressure-correction method,the two methods above were respectively used to simulate the flooding process of the water and oil and the motions of a double hull tanker whose inner shell and hull damaged at the same time. The results of the simulation in calm water were compared to those of FLUENT simulation,which validated the accuracy of the method in this paper, and the calculating time was also much less than that of FLUENT took. As for the wave condition, the most dangerous wave frequency was chosen according to the rolling amplitude frequency response curve of the intact ship.