Numerical Simulation Of The Dynamic Response Of Local Structure Due To Slamming Loads

When the ship is navigating in adverse conditions, slamming is easily occurred when the hull reenter the water because of the severe heave and pitch motion. Slamming will result in local structural damage and the elastic vibration of hull girder which will threaten the ship's longitudinal strength security. With the ship's large scale and high speed, slamming is becoming more susceptible and greater harm to the ship structure. Slamming loads is an important part of wave loads, and the intensity security under slamming loads has been seen as one of the ship safety standards by major classification societies.In this paper, the Wager's theory is seen as a guide, and the transient dynamic analysis software which called MSC.DYTRAN is used to simulate the process of slamming into the water. First, the slamming process of rigid wedge is simulated, and the slamming force and velocity of the wedge which ramp angle is 30 degrees were compared with Zhao's experimental results, both in good agreement, which verifies the feasibility of the simulation method and precision. Second, the ramp angle and velocity were changed and parameter sensitivity was analyzed, slamming pressure coefficient was derived and compared with Wagner's theory result and Chuang's experiment result, and the spatial distribution of slamming pressure was studied. Finally, a flat stiffened plate model was modeled to simulate the elastic body slamming. By comparing the slamming loads of elastic and rigid body and indicated that the presence of elastic effect reduce the peak value of slamming loads, and the greater the speed, flexibility was more obvious. Change the speed and base plate thickness of the flat panel, parameter sensitivity was analyzed and the structural response with these parameters was obtained.