Abstract. Methods for determining the maximum lift coefficient and critical angle of attack of a subsonic airfoil are considered to refine an empirical-analytical method for calculating the aerodynamic characteristics of an isolated wing of a subsonic aircraft. Determining these quantities is an important design stage, as they limit the operational angle-of-attack range and determine aircraft maneuverability. The aerodynamic characteristics of subsonic airfoils of various thicknesses and cambers from the NACA series, as well as the NASA GA(W)-1 airfoil, were calculated at different Reynolds numbers using specialized programs implementing computational aerodynamics methods and CFD software packages for flow simulation. The use of these methods for determining aerodynamic characteristics will reduce the volume of costly experimental testing in aircraft design. The computational tools used included programs based on the panel method with an integral boundary-layer model accounting for viscous-inviscid interaction, and the CFD software package, which implements solutions to the Reynolds-averaged Navier–Stokes equations using differential turbulence models. During the numerical simulation of flow over a subsonic airfoil, a grid convergence study was performed to justify the choice of computational grids ensuring stable and accurate results. The results obtained were compared with experimental wind-tunnel data reported in the scientific and technical literature. The analysis included a comparison of lift-coefficient versus angle-of-attack curves, identification of flow-separation points, and assessment of the accuracy of critical-angle-of-attack predictions. It is concluded that the programs are applicable to calculating the aerodynamic characterristics of a subsonic airfoil for estimating its maximum lift coefficient and critical angle of attack. Based on the results of the study, recommendations are formulated for selecting software to determine these parameters, offering the optimal combination of accuracy and computational efficiency for preliminary assessment at early stages of aircraft design.

Keywords: subsonic airfoil, airfoil aerodynamic characteristics, lift coefficient, critical angle of attack, numerical flow simulation, panel method

For citation: Kurkova M. K., Mikhaylov D. S., Tishchenko D. Yu., Lapteva L. A. Analysis of methods for determining the aerodynamic characteristics of a subsonic airfoil to refine an empirical-analytical method for calculating the maximum lift coefficient and critical angle of attack of a wing. Aerospace Engineering and Technology. 2026. Vol. 4, no. 1, pp. 11–31. (In Russ.) https://doi.org/10.52467/2949-401X-2026-4-1-32-50; https://elibrary.ru/XWFSFS

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