Análise de um perfil aerodinâmico em condições de escoamento rarefeito aplicado para diferentes ângulos de ataque

Abstract

This paper aims at evaluating the flow around the aerodynamic profile NACA 4412 under flow conditions which are rarefied, incompressible, and in laminar regime, applied for different angles of attack through computational simulation performed in the ANSYS Fluent software. The simulation took place using the Spalart-Allmaras one-equation turbulence model, with the angle of attack varying from 0 to 18° and flight altitudes of 0, 1, 5 and 10 km. The 1976 Standard Atmosphere was used as the basis for the values of pressure, density and viscosity. The lift and drag coefficients, pressure coefficient along the chord, velocity contour, and maximum load that the profile can sustain in level flight were obtained considering a hypothetical aircraft and disregarding power losses by altitude or induced drag. It was observed that the lift and drag coefficients have their value reduced by raising the flight altitude, as well as the pressure coefficients. The speed contour does not change with altitude. However, it was observed that the airfoil becomes more sensitive to stall at higher altitudes and maintained speed. [resumo fornecido pelo autor]