Numerical Simulation And Study Of An Energy Capture Device Using The Roll Motion Of The Ship

The increasing number of merchant ships to facilitate international trade has also led to an increase in fossil fuel consumption and pollutant emissions from ships,it is important to reduce pollutant emissions from ships and find new sources of renewable.When ships encounter wind and waves,the violent rolling motion of the hull results in an abundance of mechanical energy.A ship-mounted device has been designed to capture the mechanical energy of the hull,thereby the device can capture and use wave energy indirectly.A schematic diagram of the device was drawn by using Solid Works software;the working principle of the device was introduced in the context of a 50,000-ton tanker;using MATLAB as the simulation platform,a coupled mathematical model was established based on the rolling motion of the ship and the motion of the slider in the device;the Mass-Damping-Spring model of the slider motion was solved using the Newmark-Beta method.The data on the capture power of the device,the Gravity component in the device,the angular displacement and the linear velocity of the slider are obtained through the simulation.The effect of different combinations of spring stiffness（K）and system damping coefficient（C）on the energy capture effect of the device was calculated in the given conditions,and the results showed that the maximum average power of the device was177 W when K=300N/m and C=32N/（m/s）.The effect of the mass of the slider and the track radius of the device on the energy capture was investigated,the mass of the slider corresponding to the maximum power generated by the device is constant within a certain radius of the track.In addition,the ship’s rolling period and rolling angle have a greater influence on the power of the device,and the average power is greater for a ship with a larger rolling angle under the same rolling period.Besides,the average power is relatively high when the rolling period of 7.5 to 10 s.Finally,the energy capture effect of the device in real sea conditions is discussed through simulation.