Geometric Design And Aerodynamic Simulation For The Wind Turbine Blades

Countries all over the world are increasing the development dynamics of new energy, facing the increasing pressure of energy demand and environment protection. Wind energy is the most representative one of the renewable energies, which has important signification in protecting environment, maintaining ecological balance, reducing the dependence on the conventional source of energy and improving energy structure. The blade is the key part of the Horizontal-axis wind turbine which is the uppermost form for the utilization of wind energy. The shape design and aerodynamic characteristics of blades have been attracting a wide spread attention since the wind turbine was widely used. Conversion efficiency of wind turbine is determined by the shape of blades which occupies a decisive position in the wind turbine designing. Involving in technical privacy protection, the known foreign blade manufacturers don't open the methods of designing. Meanwhile, there is little research on the aerodynamic characteristics of blades at home. So it's necessary to master and study the design technology of blade, which has positive meanings for the development of wind energy industry and the mastery of independent intellectual property.The paper studies the optimal design and aerodynamics performance calculation and analysis for the 1.5MW wind turbine blades. The main contents and conclusions are as following:Firstly, the paper studies the basic theories about wind turbine design and Wilson method, based on blade element momentum theory, the mathematical model of optimum design of wind turbine blade is put out combining with Wilson design method, and the primary accounting routine of design calculation is designed with MATLAB. In order to process and manufacture conveniently, the torsional angel and chord length of blade are also linearized, and the results of parameters are listed out.Then, it processes data of discrete points in the aerofoil combining with coordinate transformation relation and the matrix operation of MATLAB software, and the actual coordinate data for the calculated points is brought. The cross section curves of the blades are drawn by cubic b-spline surface based on the free surface modeling function of UG, and then the three-dimensional model of blades is established. The mesh of the flow field model of blade is generated by the professional software Gambit, and then the boundary conditions are fixed on.Finally, numerical simulation in the related velocity is conduced with the CFD software FLUENT. Pressure Based, segregated, steady implicit are set in the solver. Turbulence model is SST k -ω. Pressure-velocity coupling scheme is SIMPLEC. Discretization scheme is Second Order Upwind scheme. There are presented in the form of velocity vectors/turbulence intensity/static pressure of blade surface, which are analyzed, and then the motion law and the flow detail of blade flow field are pointed out, in favor of improving the flow field of blade furtherly. Finally it lists the forces and torques of wind turbine, which can give the theoretical parameters for the next design of spindle and gearbox, and the actual power and wind energy utilization ratio are calculated.