Research On Application Of Leading Edge Auxiliary Airfoil To Horizontal Axis Wind Turbine

Wind power generation has a broad development prospect due to its clean and renewable characteristics.As an important part of wind energy absorption,wind turbine has problems such as low utilization rate of wind energy and serious separation of root flow.Therefore,the development of efficient wind turbine is crucial for the sustainable development of wind power.At present,flow control technology can play a role in increasing lift,reducing drag,damping and noise reduction,and is widely used in wind turbine blades.With the addition of auxiliary airfoils to the leading edge of the blade,the structure is simple and easy to implement,and the lift increase effect is significant at a large Angle of attack.Therefore,this paper explores the effect of adding such isolated small structures to the wind airfoil and the leading edge of the blade on the aerodynamic performance of the wind airfoil and the blade.is an important direction for the development of the new energy industry in the future.As an important part of wind energy absorption,wind turbines have problems such as low utilization rate of wind energy and serious separation of root flow.Therefore,the development of efficient wind turbines is crucial for the sustainable development of wind power.At present,flow control technology can play a role in increasing lift,reducing drag,damping and noise reduction,and is widely used in wind turbine blades.With the addition of auxiliary leading edge small airfoils to the leading edge of the blade,the structure is simple and the lifting is obviously an effective measure to increase the power of the wind turbine.The main wing of the fan in this paper adopts S809 airfoil,and the commonly used leading edge auxiliary airfoil NACA0012 is selected to study its influence on the aerodynamic performance of the main wing,and then it is applied to the Phase VI wind wheel model.The specific content is as follows:1.Through numerical calculation of the original Phase VI wind turbine and comparison with experimental values,the reliability of the three-dimensional numerical simulation was verified.The number of grids in the model was verified to be independent.The aerodynamic characteristics of the original fan under different wind speeds,such as aerodynamic power,wind pressure coefficient,torque coefficient and blade surface flow separation,were studied.2.Appropriate turbulence model can make the simulation of airfoil and fan flow field more accurate.Firstly,three commonly used turbulence models are compared,the research object is S809 airfoil.Through comparison,the turbulence model which can best represent the airfoil flow field is obtained.Then the S809 airfoil is used as the main wing,and the leading edge auxiliary wing is added to the leading edge.The key position parameters are studied(the relative chord length of the auxiliary wing is small S_c,the included Angle between the main chord and the auxiliary chord is S_θ,and the distance between the leading edge of the main wing and the leading edge of the auxiliary wing is S_L).The results show that different position parameters of the leading edge auxiliary airfoil have a significant effect on the aerodynamic performance of the airfoil,and this control device can obviously enhance the aerodynamic performance of the blade under the large Angle of attack of the airfoil.The lifting mechanism of the leading edge auxiliary airfoil is analyzed and studied.3.Based on the study of two-dimensional airfoil,two kinds of auxiliary leading edge airfoils with different parameters were added on the suction surface of the wind turbine blade.The effectiveness of the two kinds of auxiliary leading edge airfoils in horizontal axis wind turbine was verified by numerical simulation.The aerodynamic power improvement effect of the improved wind turbine model is studied under the five wind speeds of 7m/s,10m/s,13m/s,15m/s and 20m/s.Under the inlet wind speed of 7m/s,15m/s and 20m/s,the aerodynamic performance of the modified wind turbine with two different leading edge auxiliary slats,such as blade flow separation,blade pressure coefficient distribution and wake flow distribution,was compared with the original wind turbine.