Investigation On Hydrodynamic And Energy Conversion Characteristics Of A Floating Multi-dimensional Oscillating Pendulum Wave Energy Convertor

The oscillating float wave energy power generation device is a widely studied form of wave energy device,which is widely popular due to its excellent energy conversion efficiency and high integration ability.However,due to the reciprocating impact loads caused by floats on offshore platforms,breakwaters,and other structures,the service life of wave energy devices and marine structures is affected.In addition,the complex ocean environment,a single wave direction,and the reflection and attenuation problems of structures can all reduce the energy capture efficiency of wave energy devices.The pendulum wave energy device has high energy conversion efficiency,but it is affected by the direction and frequency of waves,and its bottom structure is severely limited by water depth.Therefore,combining the oscillating float wave energy device with the pendulum wave energy device and integrating it on a floating platform can not only reduce research costs,but also improve the energy conversion efficiency and environmental adaptability of the device,achieving functions such as electric energy flow supply and signal transfer.This investigation proposes a floating multi-dimensional oscillating pendulum wave energy convertor that combines oscillating float and pendulum wave energy devices,and uses numerical simulation to explore the hydrodynamic and energy conversion characteristics of the device.The main research content of this article can be divided into the following parts:(1)Propose a floating multi-dimensional oscillating pendulum wave energy device model and introduce its system composition and working principle.Obtain the solution formula for the hydrodynamic coefficient of the device,as well as the time domain motion equation of the device and the calculation method for the capture width ratio.Establish numerical models for a single cantilever wave energy device and a multi cantilever wave energy device,and use AQWA to verify the single float hinge model and the hinge double floating body model.Through comparison of hinge point motion data,it was found that the simulation effect was good,and the theoretical and experimental data were consistent.(2)Based on time-domain analysis methods,the motion response and capture width ratio of the device under different environmental conditions were calculated using a single cantilever wave energy device model and a multi cantilever wave energy device model.At the same time,by setting different device geometric parameters such as float radius,length,cantilever angle,etc.,explore the rotation of the device hinge point and the variation of float capture width ratio with different geometric feature parameters.Finally,a new numerical model of the device was established through selection,and the maximum capture width ratio that the device can achieve under resonance effect was studied.The results indicate that the main factor affecting the hydrodynamic and energy capture characteristics of a single cantilever wave energy device is environmental conditions,while the key factor affecting the hydrodynamic and energy capture characteristics of a multi cantilever wave energy device is the coupling distance between floating bodies.After parameter selection,the capture width ratio of the numerical models of the two devices has been effectively improved.The capture width ratio of the multi cantilever wave energy device is slightly smaller than that of the single cantilever wave energy device,but its power generation is greater than that of the single cantilever wave energy device.(3)A hydraulic power generation system for single cantilever wave energy devices and multiple cantilever wave energy devices was built using the AMESim platform,and the second and third level energy conversion characteristics of wave energy devices were explored.Introduced the composition and working principle of various components in the hydraulic system.Based on the hydrodynamic response calculation results of the device as the displacement signal input of the hydraulic cylinder,explore the influence of hydraulic component parameters on the hydraulic power generation system of the multi cantilever wave energy device,and select appropriate component parameters to study the total energy conversion efficiency of the multi cantilever wave energy device.Research has shown that selecting appropriate hydraulic component parameters can effectively increase system stability and improve the energy conversion efficiency of wave energy devices.By utilizing the resonance effect,the energy conversion efficiency of the multi cantilever wave energy device after parameter selection has been improved from the initial 19.6% to 53.3%.