Numerical study on flow characteristics of airfoil with bionic micro-grooves

Three airfoil models with bionic micro-grooves were developed to investigate the effect of the bionic micro-grooves on the airfoil flow field and aerodynamic performance. Large eddy simulation (LES) was used to predict the flow field around the airfoil. The Re were 1.6 × 10 5 and 2 × 10 5 , and the angle of attack was 6°. The results show that all three airfoils reduce the velocity gradient at the airfoil suction surface near the wall and the energy loss in the boundary layer. The area of the recirculation zone of the H1 and H2 airfoils is significantly reduced. However, when the Re is 1.6 × 10 5 , the area of the recirculation zone of the H3 airfoil increases. The aerodynamic performance of all three airfoils was improved. When the Re is 1.6 × 10 5 , the aerodynamic performance of the H1 airfoil is improved most significantly, and the drag reduction rate reaches 16.41%. When the Re is 2 × 10 5 , the aerodynamic performance improvement of H2 is the most obvious, and the drag reduction rate reaches 17.45%. In order to achieve the best drag reduction effect, the position of the bionic micro-grooves should gradually approach the wing's tail with the increase of Re.