Aerodynamic Performance Of Bionic Coupled Wind Turbine Blades Based On The Owls’ Wing

As a clean and renewable energy,wind energy has been paid more and more attention and utilized by more and more countries.With the increasing global installed capacity,the research on the aerodynamics of wind turbine blades has become more and more in-depth.The shape and aerodynamics of wind turbine blades directly affect the efficiency of wind power conversion by wind turbines.Therefore,the shape design of the wind turbine blade plays a vital role in the entire wind turbine design work.After millions of years of evolution,Owl-shaped birds have shown many excellent characteristics in their flight behavior,especially in the process of gliding and preying,they have the characteristics of silent flight,this unique characteristic and the morphological characteristics of their wings It has a direct relationship with configuration characteristics.This paper first selects the leading edge protrusion structure of the owl wing as the bionic object,designs a bionic non-smooth leading edge wind turbine blade and analyzes the influence of the non-smooth leading edge structure on the aerodynamic performance of the wind turbine blade.Then,the cross-section airfoil of owl wing is extracted by polynomial fitting method,and the optimal airfoil is selected by aerodynamic analysis.The optimal combination of wavelength and amplitude of airfoil and non smooth leading edge features is selected by orthogonal experiment.Finally,Wilson algorithm is used to design the bionic coupling wind turbine blade by using the optimal combination parameters obtained from orthogonal experiment.The S-A turbulence model is used to simulate the flow field around the prototype wind turbine blade and the bionic non-smooth leading edge wind turbine blade under low Reynolds number.The results show that the stall angle of the bionic non-smooth leading edge wind turbine blade is delayed by about 10°compared with the prototype wind turbine blade at a large angle of attack,which improves the aerodynamic performance of the wind turbine blade.The k-ωSST turbulence model is used to simulate the flow field of standard blades and bionic coupled blades by changing the tip speed ratio(TSR)at rated wind speed(5m/s).The results show that the wind energy utilization coefficient(C_P)of the bionic coupled wind turbine blade under high tip speed ratio is 17.7%higher than that of the standard blade.Further analysis of the two working conditions of TSR=2 and TSR=5,when TSR=5,the leading edge protrusion of the bionic coupled wind turbine blade can change the flow direction distribution of the airflow on the surface of the blade,so that the airflow remains attached to the suction surface Flow,thereby reducing the stall area of the suction surface of the blade,enabling the wind turbine to obtain higher torque and increasing power generation.The designed standard blades and bionic coupled wind turbine blades were tested for power at different wind speeds.The test results show that the bionic coupled wind turbine has a lower starting wind speed than the standard wind turbine,and with the increase of wind speed,the power coefficients of both blades are rising,but the power of the blades of bionic coupling wind turbine is higher than that of standard wind turbine blades,which makes the blades of bionic coupling type wind turbine obtain higher power generation.