The Research Of Pitching Float Type Wave Energy Conversion Device

Under the circumstance of promoting the development of new energy in the world,wave energy can be used as a clean and pollution-free renewable energy source.It can also be used to reduce gas consumption,save resources and reduce carbon dioxide emissions.It is one of the important choices in coping with energy shortage and environmental problems.It is also helpful to develop clean energy and adjust energy structure.The South China Sea is rich in wave energy resources,and the degree of exploitation and utilization is high.The float type wave energy conversion device is suitable for the South China Sea condition.Its structure is simple,and its energy absorbing components are not contacted with seawater,so its installation is convenient and reliability is high,which has attracted the attention of experts and scholars.The shape of the float has a great influence on the conversion efficiency of the pitch-float wave energy conversion device,but the theoretical studies,the numerical simulations,and the experimental studies mostly focus on limited shapes such as cylinders,spheres,etc.Therefore,this paper studies the configuration optimization of the pitch-float wave energy conversion device,and calculates and analyzes the hydrodynamic performance of the device.First,the commercial software ANSYS-AQWA is used to calculate and analyze the hydrodynamic performance of the three common shapes of floats at the bottom of the ball,the bottom of the cone,and the bottom of the platform.Based on this,the design of the shape and the internal layout of the float is optimized.Then,the hydrodynamic model of the pitching float is established to simulate the hydrodynamic characteristics of the motion of the pitching float in the wave,the coupled motion equation of the built-in swing plate and the float is studied,and programmed into the float motion.The power and the capture width ratio of the designed float are calculated by MATLAB software,and analyze the influence of various factors on the power of the device.Finally,the second development of AQWA is carried out with FORTRAN software.Under the condition of regular waves and irregular waves,the movement,stress and safety performance of the device are checked and analyzed.The results show that:The performance of the ball bottom float is the best in the three shapes;When the shape is optimized,the width and the arc of the float have great influence on the roll performance;When the local component is optimized,the moment of inertia has a great influence on the pitching performance;The hydrodynamic performance of the designed floater meets the requirements of the marine mobile platform,and the performance of the pitching response is great;The power of the device increases with the increase of the damping coefficient of PTO and the inertia I₃ of the built-in swing body;Under the conditions of regular and irregular waves,the device can operate safely and steadily,and the reliability is high.The research results in this paper are of great significance for the study on the influence of the shape of the float type wave energy device on the hydrodynamic performance in the South China Sea,and on the improvement of the design of the pitching float type wave energy conversion device.