Study On CFD Numerical Simulation Of Coupled Motions Of Tidal Current Power Station

In recent years,countries have paid more and more attention to the development and utilization of conventional energy resources in the face of the increasing depletion of conventional energy resources.As an important kind of ocean energy,tidal current energy has great density,strong predictability and strong energy stability,which makes it has unique advantages in development and utilization compared with other kinds of marine energy,which makes the research on tidal current power generation device become a hot spot in recent years.Most of the previous studies on the coupled motion characteristics of tidal current power stations are based on the potential flow theory to study the coupling characteristics of the turbine,carrier and mooring system,and most of the studies on the impact of the turbine on the carrier or the carrier on the turbine are unidirectional.Based on the viscous CFD method,a turbine-carrier-all mooring system coupling viscous numerical simulation method is established in this paper.In this paper,firstly,the design requirements,design environmental conditions and reference specifications are determined by referring to literature.According to the reference specifications and empirical formulas,the main scale parameters and structure form of the appropriate turbine generating device and tidal current power station are determined,and the weight,gravity center position,displacement and floating center position of the tidal current power station are calculated.Then,this paper introduces the theoretical method of applying CFD method to numerical simulation of vertical axis turbine,and calculates the energy utilization rate of vertical axis turbine by using STAR CCM+.The simulation results are compared with the test results,which verifies the reliability of the numerical simulation method.Secondly,through the DFBI module and overlapping grid method of STAR CCM + software,the response of turbine motion to carrier motion and the influence of carrier motion on the hydrodynamic characteristics of turbine are obtained by analyzing the working state of body and turbine under uniform flow condition and wave current condition,besides,the hydrodynamic characteristics of the turbine at different speeds are also obtained through the coupling numerical simulation.Finally,the coupled motion of the turbine-carrier-mooring system is analyzed by using CFD method,and the influence of different wavelength and wave height conditions on the motion characteristics of the carrier of the floating tidal power generation unit,as well as the turbine energy utilization rate,thrust coefficient and lateral force coefficient are revealed.The CFD prediction method based on the coupling characteristics of tidal current power station is established in this paper can forecast the coupling characteristics of tidal current power stations,also can be real-time output turbine load,power and flow field information.The research results of this parper can provide theoretical guidance and technical support for the design and engineering application of the turbine and carrier of floating tidal current power station.