| There are many types of wind turbines.Its common needs is taken to make the best use of their characteristics and application laws to improve the efficiency of wind energy.In this paper,the ?-type vertical axis wind turbine is taken as the research object.Under the condition of wind energy utilization,its aerodynamic characteristics and installation in the building location,height and layout of wind field configuration rules are studied by means of CFD simulation.In this paper,the S-A turbulence model is used to study the aerodynamic characteristics of the NACA0012 airfoil for ?-type vertical axis wind turbine.The airfoil has a chord length of 100 mm and a relative thickness of 12 mm.Lift coefficient,drag coefficient and lift-to-drag ratio is obtained by analysis their curve along with the change angle of attack,so that we can find the best angle of attack of airfoil.Then,the change process of the airfoil stall is analyzed from the static pressure intensity cloud diagram and the velocity streamline of the airfoil with the angle of attack.The law of performance is as follows: with the increase of angle of attack(2~0-18~0),the lift coefficient of NACA0012 airfoil curve exhibits increase first and then decrease.The lift coefficient grows to a maximum of 0.34 when the angle of attack is13.50.However,drag coefficient has been slowly rising.Lift-to-drag ratio curve 's trend is similar to lift coefficient curve along with the change of angle of attack.Lift-to-drag ratio up to maximum value 13 when the angle of attack is 8.50.For further study the aerodynamic characteristics of ?-type vertical axis wind turbine which installed in the ground,its wind power curve along with tip-speed ratio is calculated by means of CFD simulation and wind-tunnel flow test respectively.Results show that the change of wind-tunnel flow test measured value is same as that the CFD method.That is to say curves which has obtained by the two methods is roughly the same change trend.Its maximum wind power coefficient is about 19% when tip speed ratio is about 4.2.To some extent,this also shows that turbulent model and calculation algorithm which had selected is reasonable in the CFD calculation method.On this basis,the ?-type vertical axis wind turbines installation and configuration in the surrounding wind environment of three typical building structures mainly studied.Firstly,thenumerical simulation of the surrounding environment of three typical buildings without wind turbine is carried out.The evaluation index is that the wind speed ratio greater than 1 and turbulence intensity less than 25%.The simulation shows that the height of the wind turbine which installed on flat roof is different when the wind direction is different at the same wind speed.Wind aggregation effect of Channel building structure is stronger than that of a single flat roof.Hollow building structure have smaller areas for the wind turbines installation compared with flat roof.But both of them have the characteristic of less turbulence for wind turbines installation.From this foundation,considering the influence of turbine wake and energy absorption in the wind turbine operation process.This paper,on the condition that wind turbine have been installed in the front for building structure.Then,to analysis wind turbine's flow field that will be installed in the middle and rear of the building structure.The feasibility and rationality of improving installation height method and dislocation installation method were discussed. |
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