Aerodynamic Characteristics of NACA 0018 Based on CFD Method at Low Reynolds Number

The aerodynamic properties of the airfoil are of great significance in improving the aerodynamic properties of the small fixed-wing UAV. This study demonstrates a numerical evaluation of the planar aerodynamic properties of a typical NACA 0018 airfoil at Reynolds numbers varying between 3105 and 5105 as well as angles of attack between 0 and 20. The computational fluid dynamics (CFD) flow simulation tool ANSYS Fluent, which is based on the limited volume approach, is used to perform the computation. Based on the continuity equation and Navier-Stokes control equation, the Spalart-Allmaras turbulence model is used for simulation. The research reveals the relationship between the pressure distribution, lift and drag ratio of the airfoil and the angle of attack at diverse Reynolds numbers and ultimately reaches the conclusion that NACA 0018s best condition of aerodynamic properties is at the Reynolds number of 5105 and under the angles of attack within 12~14. This analysis provides a basis for wing optimization design and can be widely used in aerospace and wind turbine design.