Hydrodynamic Performance Of Buoyancy Pendulum Wave Energy Conversion Device: Experimental And Numerical Analysis

There are nearly 3 million square kilometers of ocean land in China and its coastline is nearly 18000 kilometers.So it contains a great deal of wave energy resources.It has significant advantages for the sustainable development of human society to improve the wave energy development technology [1-2].It can not only solve the power shortage problems of the islands which have a large number of people living in,but also supply electricity for offshore aquaculture lighting.Besides that,it also can reduce the cost of generating electricity from wave.The United States,Britain,Japan,Norway and other coastal countries have pay more attention on the development and utilization of wave energy.These countries have developed a large number of different forms of wave energy conversion devices based on different design ideas and the actual situations of their country.However,few attentions have been paid on the wave energy conversion device in our country in past years.Therefore,it is necessary to intensify the research and the related funds on the hydrodynamic performance of the wave energy conversion device.This paper mainly presents an experimental study on the hydrodynamic performance of buoyancy pendulum wave energy conversion device in regular and irregular waves.The magnetic particle brake is controlled by the magnetizing current which is used to simulate the power take-off system.Based on the theory of linear potential flow,the three-dimensional frequency domain model of the buoyancy pendulum wave energy conversion device is established.By comparing the experimental results with the numerical results,the rationality of the experimental arrangement is verified.The effects of wave elements and the moment of inertia on the rotational angle,the hydrodynamic pressure on the surface of the plate and the capture width ratio are studied.In the case of JONSWAP spectrum and PM spectrum irregular wave,the influence of wave conditions and damping torque on the hydrodynamic performance of the model are studied.The results show that the wave elements,the moment of inertia of the pendulum plate and the wave conditions have important influence on the hydrodynamic performance of buoyancy pendulum wave energy conversion device.In addition,the capture width ratio and the capture power of the device are not one-to-one.So we should not regard the capture width ratio as the only measure of the merits of the wave energy conversion device.