Aerodynamic performance of a 30P30N three-element airfoil using the RANS-SST turbulence model

This study presents a numerical investigation of the aerodynamic behavior of the three-element high-lift airfoil 30P30N under low-speed flow conditions relevant to takeoff and landing operations. The analysis is performed using the Reynolds-averaged Navier-Stokes (RANS) equations coupled with the Shear Stress Transport (SST) turbulence model, implemented within a finite-element framework. The primary objective of the work is to assess the capability and limitations of a two-dimensional steady RANS-SST approach for modeling complex multi-element airfoil flows. Numerical simulations are conducted for several discrete angles of attack, and the resulting flow fields and pressure coefficient distributions on all airfoil elements are analyzed in detail. The numerical model used was validated by comparing the obtained results with experimental data obtained in a wind tunnel for the 30P30N configuration. A comparative analysis revealed satisfactory agreement between the calculated and experimental pressure coefficient distributions, particularly at low and moderate angles of attack. This demonstrates the ability of the SST model to accurately describe key aerodynamic processes, including boundary layer formation and development, the influence of adverse pressure gradients, and the interaction of flows between airfoil elements. As the angle of attack increases, localized discrepancies are revealed in zones with pronounced pressure gradients and the potential onset of flow separation. Such deviations are likely due to limitations of the stationary two-dimensional formulation of the problem, which does not take into account spatial and unsteady flow characteristics, the role of which increases as more intense aerodynamic regimes are approached. Despite these limitations, the study provides a systematic evaluation of the finite-element RANS–SST methodology for high-lift airfoil analysis and offers insights into its applicability as a computationally efficient tool for preliminary aerodynamic assessment and validation of multi-element wing configurations.