Research On Motion And Output Power Characteristics Of The Hydraulic Point Wave Energy Converter

With the increasing depletion of the terrestrial fossil energy, humanity willturn its attention to the vast ocean. Wave energy is a kind of energy whichcontains a large amount of renewable energy, and China has vast ocean area.so,developping a kind of hydraulic-point wave energy converter which is practical,reliable,and efficient,has great prospect and practical significance.Based on linear wave theory, this paper solves the linear solution of thewave potential function when using the boundary conditions and the controlequation,and finds the dispersion relation between wave frequency and the wavenumber; Then, using the Froude-Krylov assumptions, the force and movementcharacteristics of the floating-body in the linear wave are solving; At last,itestablishs a mathematical model of the wave energy absorption efficiency, toestimate the wave energy absorption efficiency of the hydraulic-point waveconverter.To further explore the force characteristics of the upright-cylindricalfloating body in waves, a two-dimensional wave flume model is established inthe FLUENT,which is used to generate the two-dimensional regular waves.Inthe model,the physical push plate’s movement is defined by a UDF function,andit moves in the sine law;At the end part of the sink, a kind of damping source isadded to impair wave energy.When the push plate’s moving size is changed, thewave characteristics is recorded and compared. At last, the attenuationcharacteristics of the waves along the propagation direction is finded.A two-dimensional axisymmetric model of the vertical cylindrical floatingbody is established in the FLUENT.when the floating body is forced moving nearthe free surface, it is important to study the vertical cylindrical floating bodyradiation in the still water. Finally, the additional mass and additional damping ofthe movement of the floating body is solving, and then the variation dependingon its movement frequency is analysed.In order to better to mechanical energy of the floating-body into electricalenergy, a hydraulic model of energy conversion is established Using the AMEsimsoftware.In this model, the periodic hydraulic energy is stabilized when it flowsthrough the rectifier circuit formed by the check valves and accumulators.Thenthe current promote the motor rotation, thereby bringing the generator.Thesimulation results show that, an appropriate increase in the effective volume of the accumulator and select a reasonable pre-charge pressure, are beneficial toreduce the speed fluctuation of the load, and it can improve energy conversionefficiency of hydraulic systems.