Research On Damping Configuration And Control Strategy Of Variable-cycle Anti-rolling Tank

Anti-rolling tank is the stabilizing equipment which can provide good stabilization at anyvessel speed. The tank produces high and low level difference by the energy of the ship rollmotion, so that to provide resistance to reduce the roll motion of the ship by the gravitydifference of two wing tank. Variable-cycle anti-rolling tank is one of the new type tanksdeveloped in recent years. It is designed based on the passive anti-rolling tank. The movementof water is controlled by the intermediate damping plate in order to change the tank cycle. Thetank can adapt to different sea conditions and provide good stabilization in its work scope.The tank has many strongpoints like simple structure, low cost, a wide range cycle and has thefunctions of ice-break and heel-resistance. So it is widely used in various ships.The research method on variable-cycle anti-rolling tank is based on a large number ofdomestic and international data and the original study. Then, the paper established themathematical models which were needed: wave motion mathematical model andship-variable-cycle anti-rolling tank system mathematical model. The force of the ship-tanksystem and tank parameters were discussed. Then the evaluation methods of anti-rolling tankstabilization were given.Take a model tank for example, the paper established VOF model of variable-cycleanti-rolling tank using fluid dynamics method. The movement of the fluid and the cause of thedamp were discussed in theory. And the paper researched the impact on the tank caused bydamping plate location and structure. At the same time, the impact of the intermediatedamping plate on the damp and cycle was discussed. Also, the impact of the local dampstructure was analyzed. Through the analysis of the tank structure, the study is helpful to tankstructure design and tank control method.On the basis of the wave-ship-tank system mathematical model, the simulation modelwas built. The control strategy of the variable-cycle anti-rolling tank and the stabilizationeffect in different sailing conditions were researched. Also, the paper analyzed thestabilization effect with different damping on one work condition. Then the stabilizationeffect in different sailing conditions were simulated.The impact of the tank on ship in the state of rotation is analyzed. Then, the motionequation of ship-tank system in the state of rotation is built. Under the matlab/simulinksimulation environment, the paper researched the impact of the tank on the ship in the rollangle, heel angle, turning diameter and turning cycle under the conditions of wave and no wave.