Studying aerodynamic performances of the low-reynolds-number airfoil of solar energy UAV

In order to develop high attitude and low speed solar energy UAV, numerical computations of airfoil were used to analyze the aerodynamic characteristics of high-lift airfoil with high camber in a range of low Reynolds number. Finite volume method and transition k-kl-w turbulence model were used to solve the 2D Reynolds-averaged Navier-Stokes equations. To prove the accuracy of this method, the SD7037 airfoil was selected to undergo an analysis of influences caused by different types of grids and undergo a verification between the numerical results and experimental results. We conducted a detailed analysis of aerodynamic forces and summarized their trends of variation with Reynolds number, then studied the characters of the flow at representative Reynolds numbers and explained the reasons of high lift, and at last, through studying the nonlinear characteristics of the lift discussed the flow mechanism of the stall of the airfoil at large relative angle of attack.