Research On Hydrodynamic Performance Of Wave Flow Coupling Power Generation Device

With the rapid development of the global economy,the energy crisis and the pollution of the natural ecological environment have been appeared.While maintaining economic higher rapid growth,developing renewable clean energy has become an important means to achieve sustainable development of human society.Scholars from all over the world are gradually attracted by huge reserves of ocean energy resourcesFirst,this thesis introduces a new wave flow coupling power generation dev-ice,which can convert wave energy and tidal current energy into electricity for use.But this power generation device is currently during the design development stage without mature technology.The methods of computational fluid dynamics(CFD),design of experiment(DOE)and flume experiment are applied to research the hydrodynamic performance of the power generation device.In this paper,the selection of the impeller airfoil is analyzed.Two S-shaped airfoils are constructed by NACA M10 and NACA M19 airfoils which have different degree of curvature.The hydrodynamic analysis of the two airfoils is carried out by CFD method.The results show that the hydrodynamic performance of the S-shaped airfoil which constructed by the less curvature NACA M10 is better.The parameters of hydrodynamic performance such as the optimum angle of attack and lift drag ratio are obtained at the same time.After the parameters of the impeller airfoil are obtained,the blades of impeller are designed based on the lifting design method,and the 3D modeling of the impeller is carried out by using the CAD software.The rationality of the design was verified by analyzing the flow state of the impeller.And the thrust coefficient and torque coefficient which both can provide reference for the installation of the turbine unit in the future are calculated.Aiming at the optimization of the structural parameters of the diffuser,a method combining numerical simulation with experimental design is creatively put forward.It is found that the acceleration performances of the diffusers are obviously different under different combinations of structural parameters.And the important order of the structural parameters influencing the acceleration performance of the dome is summarized.Finally,the optimal parameter combination is obtained when the length of the expansion section is 1000 mm,the length of the middle section is 800 mm and the angle is 15.Finally,the simulation results are verified by flume test experiment.It is found that the output power of the turbine varies with the flow velocity under the forward and reverse working conditions.And the output power difference between these two working conditions is very small.The characteristic for duplex channel energy acquisition of the impeller is proved.It is found that the energy efficiency of the turbine is up to the maximum of about 16% when the velocity of water is 2m/s.It verifies the rationality of the design of the turbine,and provides data and references for the future design and research of the turbine.