Vawt Pneumatic Design Based On CFD Numerical Simulation

With the development of society, the need for energy has increased constantly. For the worry about pollution to the world, developing and exploiting new energy source,especially renewable energy source, has been an urgent task for each country. Wind energy, as one kind of renewable energy sources, which can be used in large scales, has been paid a lot of attention to, and has gained great development in recent years.Wind energy is obtained by the wind turbines to generate power. Wind turbines can be classified into horizontal axis wind turbines (HAWT) and vertical axis wind turbines (VAWT). HAWT has been adopted worldwide for its proven technology. With the research going on, VAWT are now arousing a lot of attention for its various advantages over HAWT, and to develop VAWT with good performance has been on the agenda for a lot of wind turbine companies. Wind turbine blades, as one of the key parts for VAWT, accounts for 1/3 of the total wind turbine manufacturing cost, while their aerodynamic performance also decides the power coefficient of the wind turbines. As a result, pneumatic design is to be finished in this paper with CFD method.The development history of VAWT is concluded in this paper and then the application of CFD method in the design of VAWT design. The parameters to affect the wind turbines aerodynamic performance are also obtained: blade airfoil, speed ratio, blade density, the wind turbine shape, and so on. Furthermore, the mathematical theory foundation of CFD software (FLUENT) is concluded, and the simulation process is introduced. The CFD method is adopted to calculate drag and lift coefficients under different low Reynolds number, and then a blade airfoil with good aerodynamic performance is obtained. The very airfoil is used to make a 2-D model of VAWT, and then the CFD simulation is performed to the 2-D model. With the comparison results of wind power coefficients and flow distribution under different parameters, the wind power coefficient variation law and flow distribution variation law can be obtained, which is the foundation of 3-D parameters design of VAWT. Furthermore, a 3D wind turbine is designed with the rated power 100kW with the results got in the 2-D analysis, and 3D CFD analysis is applied. Then the rated power can be checked.The research results are valuable for the engineering application, and also have magnificent guidance meaning for the VAWT pneumatic design.