Experimental Study On The Pendulum Wave Energy Conversion Device

With the economic and social development, the energy for human demand is increasing, while the global energy reserves are limited. Especially the oil crisis in the last century made people a clear understanding of the importance of energy for the national economic and social development. In order to solve the bottleneck problem of energy supply, the ocean has been the focus of the human kind. Ocean area takes about 70% of the total area of the earth and huge amount of energy, is stored in it, so by now many countries have been exploiting it.This thesis first introduces the development of wave energy utilization and some promising wave energy converters both at home and abroad, Then two pendulum wave energy converter models are designed to conduct the experimental research, which are trapezium and cylindrical type, respectively. In the experiment different electric resistances are added to the electrical generator as resistive loads to represent different work conditions so as to get the relationship between resistive loads and wave energy conversion efficiency. The waves measured in the wave flume were composite because of the reflection of the models. So the AM method is adapted to separate the incident and reflected waves to get the incident wave height. It is shown that the total conversion efficiency is low when the low wave height condition, but goes up with the increment of the incident wave height. The total conversion efficiency goes down when the incident wave height come to a certain higher value. This is mainly due to the mechanical interval between the pendulum plate and the speed change mechanisms. When the incident wave height is lower, the pitch angle is smaller too, and the energy losses become larger. And the viscous drag damping components become dominant when the incident wave height becomes higher. It is shown that the conversion efficiency of the trapezium type is much higher than that of the cylindrical type.