Análise das forças aerodinâmicas no aerofólio NACA 2412 com sucção

Abstract

This work presents the investigation of aerodynamic forces, lift and drag, in the NACA 2412 airfoil with suction, submitted to subsonic, incompressible and laminar flow. The ABS material was choosing for the manufacture of the airfoil. The numerical simulation was used to get pressure distribution around the NACA 2412 airfoil, due to the air flow imposed by the wind tunnel. The mechanical stresses on the NACA 2412 airfoil with orifices was calculated by SolidWorks 2016 ® software. The results showed that the profile supports the mechanical stresses due to air flow. The 3D printing was used to manufacture NACA 2412 airfoil with orifices. This profile was installed in the test section of the subsonic wind tunnel of the Aerodynamics and Heat Transfer Laboratory at Unipampa – Campus Alegrete. Three experiments were carried out: with the airfoil without orifices, with the airfoil with orifices and with the airfoil with suction. To obtain the aerodynamic forces, two apparatuses were assembled and adjusted: one to obtain the sustained mass and the other for the dragged mass. Sustained and dragged mass, atmospheric pressure and temperature, dynamic pressure data, as well as wing geometric data were used to obtain lift and drag forces. The results of force and lift coefficient, for different angles of attack, showed to be qualitatively consistent with the results obtained in the literature, the quantitative differences may be related to the environmental conditions (temperature and atmospheric pressure) in which the experiments were carried out. In addition, the results of force and lift coefficient, for the flow over the airfoil with suction on its upper surface, presented a slightly better aerodynamic behavior (greater stall angle) than an airfoil without suction. On the other hand, it is noted that the apparatus built and used to obtain the dragged mass did not show sufficient sensitivity to adequately capture the variation in dragged mass caused by the flow around the airfoil. However, it can be observed that up to the angle of attack close to =10o, there is a “linear” increase in the drag force, which also seems to occur in the reference profile (NACA 2412 – Manual AF103 (2008)), which indicates that the apparatus used to obtain the dragged mass, with the necessary modifications and/or adjustments, can be improved, and may generate better results.