Berthing Ships' Movement And Arrangement Optimization Of Mooring Lines In Wave And Current

Over motion of berthing ships will make troubles in dock working, and unreasonable arrangement of mooring lines will lead serious accident. So how minish berthing ships' movement and arrange mooring lines effectively is very important.In this paper, ships' movement rules are summarized by studying experiment data. Compose relation formula, and for the reason that relations come from different experiment some uncertain coefficients are acceded to formula. Ships' shift value go up when load decrease. Ships' rocks get no impact from load. The effect of wave period has directional nature on rock. Wave height and wave period have independence in the effect on ship and so on.Current force increase with flow velocity in quadratic power function, and increase with ship load in linearity, and vary with the angle of flow in linearity. Ships motions put up different characteristics when the angle of wave and current changes in wave-current interactions. Because of the existence of hydraulic pressure rotate moment ships yaw have different nature from other motions.Study the pull of rope in the same method with studying motions. The nature that head line and trail line force vary with ship load is non'linearity, which approach rope characteristic curve under small load. For the reason that transverse line is short, and elasticity coefficient is bigger, its force increase with wave height and wave period in linearity.Find out the relation formula of each motion and rope elongation, and then discuss the variable for improving the efficiency of mooring line controlling. From the formula get the best controlling direction, and validate which by a mode. Harmonize every direction mooring lines, and shorten the length of berth.