Research On Lattice Boltzmann Simulation On High Reynolds Number Flow Around Marine Current Turbine

Marine Current Turbine has a vital impact on tidal current energy conversion device. The power coefficient of marine current turbine varies with the structure of the turbine. As the basic research work of the optimization of marine current turbines, hydrodynamics analysis of hydrofoil blades and the number of hydrofoil blades are very important in order to improve the power coefficient of marine current turbines.Gradually developed in recent years, lattice Boltzmann method has drawn much attention and become an important mesoscale simulation method for complex fluid modeling and simulation. It has the advantages of simple algorithm, high accuracy, direct calculation for the pressure, suitable for complex boundary conditions and parallel computations. But standard lattice Boltzmann method is unable to simulate of high Reynolds number due to the demand of error, which lead to the limitations of this method on engineering application.In this paper, lattice Boltzmann method is adopted to the application research on hydrodynamics analysis of marine current turbine. Through further research on basic theory of lattice Boltzmann method, large eddy simulation combined with lattice Boltzmann method is used to solve the problem of simulation of high Reynolds number. Though numerical simulation and comparative analysis, it is proved that the LBM-LES is accuracy and effective on simulation of high Reynolds number. By simulating flow around hydrofoil on turbulent under the conditions of different attack angles, different hydrofoil blades with different camber and thickness, the trend of hydrodynamics parameters in different hydrofoil conditions is summarized. And the corresponding streamlines and hydrodynamic curves are draw by processing and analyzing the calculation data. Based on above work, the total turbine is also simulated. Through simulation of vertical turbines with different blades number and calculation of hydrodynamics parameters, the relations between number of blades and hydrodynamics of turbine are known and regular pattern of power coefficient varies with number of blades is obtained. The research work in this paper provides reference and guidance for designing and optimizing marine current turbine.