Airfoil Aerodynamic Characteristics Study Of High Speed Propeller

Propeller-driven aircraft continue to play an important role in the development of civil aviation due to their good economic performance and wide applicability.However,as propeller aircraft speed increases,there are higher demands for improved propeller aerodynamic efficiency and noise reduction.With high-speed propellers running at higher flight and rotation speeds,the relative Mach numbers at propeller tips are generally above 0.9,and there are local supersonic regions in the subsonic flow field of high-speed aviation propellers.The resulting complex flow field,with mixed transonic flows,poses significant challenges to propeller aerodynamic design and CFD(Computational Fluid Dynamics)calculations.To design high-efficiency and low-noise high-speed aviation propellers,in-depth research on blade airfoil shapes is required.Thus,studying the aerodynamic characteristics of airfoils based on the unique characteristics of the high-speed aviation propeller flow field is vital and practical work.To obtain highly efficient high-speed aviation propellers,this study first investigated the aerodynamic characteristics of high-speed aviation propeller airfoils.Four typical airfoils were selected as study objects,including the supersonic airfoil RAE2822,the symmetric airfoil NACA4412,the high Reynolds number thin airfoil NACA65206,and NACA65-009.A mesh generation program for airfoils was developed using Fortran language,and high-quality C-type airfoil meshes were obtained.The airfoil aerodynamic characteristics were then calculated and analyzed using the open-source software CFL3 D.Based on the aerodynamic performance of the four airfoils in high-speed aviation propeller transonic flow fields,the NACA65206 airfoil was selected for high-speed aviation propeller aerodynamic design.Based on the computational method of the three-dimensional unsteady Reynolds-averaged Navier-Stokes equation coupled with turbulence models,the aerodynamic calculation of the high-speed propeller was carried out,and the maximum efficiency of the propeller at a Mach number of 0.6 was found to be82.43%.This study illustrates that the high Reynolds number thin airfoil with better aerodynamic performance plays an important role in enhancing the aerodynamic performance of the propeller in the high Mach number flow field of high-speed aviation propellers.Through CFD numerical simulation,it further validates that the high-speed aviation propellers designed in this study have high aerodynamic efficiency and the choice of airfoil is relatively ideal.