Research On New Type Of Buoy-Rope-Pulley Wave Energy Capture Technology

With the rapid development of human society,the problem of energy supply and environmental pollution are becoming increasingly serious.The development and utilization of wave energy has attracted the attention of various coastal countries because its advantages of wide distribution,large reserves,high energy flow density,clean,and renewable.Oscillating buoy wave energy convertor has become a research hotspot in the field of wave energy due to its advantages of low manufacturing,deployment,and maintenance costs,strong reliability,and high wave energy collection efficiency.The buoy-rope-drum wave energy device developed in the early stage has the advantages of low manufacturing,deployment,and maintenance costs,and strong survivability in extreme climates,but still has problems such as rope wear,weak rope-retraction ability of spring,and low wave energy collection efficiency.Therefore,this thesis proposed a new type of buoyrope-pulley wave energy capture technology to eliminate the above-mentioned defects,and it belongs to oscillating buoy wave energy convertor.This thesis attempts to use resonance theory to improve its wave energy capture efficiency and reduce its cost.The main research contents are as follows:(1)This thesis proposed a new type of buoy-rope-pulley wave energy capture technology,it used a hydraulic system to collect wave energy and retract the rope.This technology not only solved the reliability problems of rope wear and spring fatigue in the early buoy-rope-drum wave energy capture technology,but also greatly improved the rope retraction ability and eliminated the main problem that restricted the efficiency of early buoy-rope-drum wave energy capture device.(2)Based on the standard wave tank,using the idea of equivalent external placement,a physical model test platform for a new type of buoy-rope-pulley wave energy capture device was constructed,and comparable resonant and nonresonant experimental floating body models were constructed based on finite depth linear wave theory and the resonance principle.Obtained and compared the optimal capture width ratio of the two types of models through physical model experiments,it is found that the resonance technology cannot effectively improve the capture width ratio of the new type of buoy-rope-pulley wave energy capture device model.(3)Based on the two hydrodynamic simulation technologies of AQWA and OrcaFlex,the hydrodynamic simulation of the new type of buoy-rope-pulley wave energy capture device was realized,and the calculation method of its capture width ratio was derived.Based on this hydrodynamic simulation technology,the physical model experiment mentioned above was simulated,and the calculation results were in good agreement with the physical model experiment results.Therefore,it not only further verified that the resonance technology cannot effectively improve the capture width ratio of the new type of buoy-rope-pulley wave energy capture device model through theoretically,but also verified the reliability of the hydrodynamic simulation technology mentioned above.(4)To eliminate the size effect and the impact of one-way wave energy collection,based on the simulation technology described above,under three common wave conditions,including huge waves,medium waves,and small waves,full-scale prototype models of resonant and nonresonant buoy-rope-pulley wave energy capture devices with one-way and two-way acquisition characteristics were constructed.Simulations were then conducted to get the maximum wave energy capture width ratio.The research result indicates that the nonresonant buoy-ropepulley wave energy capture device with one-way acquisition has higher wave energy capture efficiency than the resonant buoy-rope-pulley wave energy capture device,so it provides a theoretical basis for the research of the new type of buoyrope-pulley wave energy capture device.