Research On Hydrodynamic Performance Of Turbine Based On Floating Breakwater

At present,the energy crisis and environmental problems are becoming more and more serious.The world has abundant marine resources,which can not only solve the energy crisis,but also serve as an environmentally friendly new energy source,and it is also the key development target of various countries.Ocean current energy is one of the youngest and fastest-growing energy,has become the focus of research by various scholars.As the core structure of the current energy utilization device,the water turbine has high requirements on the energy flow density of the sea current.The distribution of the sea current energy in the sea area of my country is uneven,and the area that can meet the requirements is small,which is an important factor hindering the development.Due to the shielding of the seawater by the structure,the bottom flow field is accelerated and the energy flow density is increased,which is in line with the working conditions of the ocean current power generation turbine.Therefore,this paper studies the combination of the current energy device and the floating breakwater,which has a certain reference value for the expansion and application of the current energy utilization device.In this paper,the STAR-CCM+ numerical simulation software is used to study the hydrodynamic performance of the coupling structure combining the ocean current power generation device and the floating breakwater.optimal working condition.Through numerical simulation,the influence of wave elements on turbine parameters is analyzed after adding waves to the uniform flow field,and it is obtained that the energy harvesting efficiency of the turbine and the axial force received increase,and the wave period has an obvious influence on the turbine.Then the turbine performs forced motion under the condition of wave flow,the pitch motion will change the performance amplitude of the hydraulic turbine,the heave will affect the performance average value,and the pitch motion has little effect on the performance.Finally,the method of overlapping grid and slip grid is used to realize the numerical model calculation of the full coupling of the turbine and the breakwater in the software.Based on the DFBI module,the coupling structure is set for mooring and three-degree-of-freedom motion,and the floating breakwater and the turbine are analyzed.The interaction between the hydraulic turbine and the breakwater will cause the breakwater to move backward,and the amplitude will become smaller;the heave balance position will move up,and the amplitude will become smaller;the pitch angle will become larger,and the amplitude will become larger..However,due to the blocking effect of the breakwater on the ocean current,the bottom flow field will be accelerated,the energy utilization rate of the turbine and the axial force coefficient will increase,the fluctuation amplitude will decrease,and the wake will become shorter.After research,the ocean current energy utilization device combined with the floating breakwater can effectively improve the energy harvesting efficiency of the turbine while stabilizing the movement of the breakwater.Under the condition of ensuring the safety of the coupling structure,it can provide ideas for the utilization of ocean current energy in the deep sea.