Investigation On Hydrodynamic Performance Of Wave Energy Float Pendulum System

With the development of the world economy,the demand for energy is increasing day by day.However,over-exploitation of fossil fuels has triggered global energy crises a few times.As a kind of renewable energy,wave energy has been paid more and more attention because of its wide distribution,large reserves and high energy density.In this paper,it classifies some common wave energy generation devices,compares and analyzes their working principles,advantages and disadvantages,which briefly introduces the research status of domestic and foreign wave energy generation technologies.Combined with the actual sea conditions in China,a new wave energy float pendulum system is designed.The device adopts a parallel bidirectional hydraulic cylinder to improve the wave energy conversion efficiency.The oscillating float of this device is immersed in seawater,and the rest of the components are installed on the shore,which can effectively avoid the erosion of seawater.The main research contents of this paper are as follows:(1)This paper introduces two commonly used wave theories,micro-amplitude theory and stochastic wave theory.Based on these two theories,the energy transport equations of regular waves and irregular waves are derived.The effects of wave height,period and water depth on wave energy transport are briefly analyzed.(2)The wave energy float pendulum system is designed independently,and several wave forces received by the float in the water are introduced in detail.Finally,the mathematical model is established for the whole system.In the MATLAB software,the Runge-Kutta method is used to solve the differential equation,and the curve of the swing angle and angular velocity of the pendulum is plotted.(3)Based on the AQWA software system,the hydrodynamic performances of cylindrical floats with different radii,cylindrical floats with different masses and cone bottom floats with different angles were analyzed.The multi-ball bottom oscillating float was designed to compare with the traditional ball bottom float.The article probes into the impact of the number and distribution of the ball on the hydrodynamic performance of the float.In this paper,the cone bottom float,the cylindrical float and the bottom float are selected for comparison.The time-domain analysis of the three types of floats is carried out in the regular wave and the irregular wave respectively,and the heave displacement,the moving speed and the acceleration of the float in the same wave environment are compared with each other.(4)A hydraulic system is set up for the wave energy float pendulum structure,and the components of the hydraulic system and its working principle are introduced.The AMESim software is used to simulate the oscillation float in the working environment of regular wave and irregular wave,and the calculation results are analyzed and the improvement scheme is proposed.(5)The oscillating float with better hydrodynamic performance is selected,and the experimental platform is built with the hydraulic system to carry out experiments to calculate the capture width ratio and power generation efficiency of the float.The experimental results fully verify the rationality of the structural design.The experimental results is compared with the previous studies,the differences are analyzed,and improvement measures are proposed.