Obtenção dos coeficientes de flutter utilizando simulações via CFD

Abstract

Studies about aerodynamic coefficients and flutter derivatives are important for structural engineering projects, being able to avoid major accidents caused by wind loading forces. The achievement of these coefficients can be by experimental tests in a wind tunnel, however, with advances in computational fluid dynamics, the achievement of these coefficients through numerical simulations is increasingly gaining prominence. In this research, a methodology that assumes a linear relationship between the force functions and the laws of motion of the structure, which allows the superposition of the answers. Known sinusoidal vibrations are applied in the middle of the characteristic length of each structure to obtain the aerodynamic coefficients. The obtained signal is treated using least squares curve fitting and later the flutter coefficients are calculated. The first analysis lies in the identification of the flutter coefficients in an airfoil in two-dimensional flow and with Reynolds number equal to 800. The second example consists of obtaining and analyzing the flutter coefficients for a rectangular geometry subjected to a flow turbulent. The k-𝜔SST turbulence model was used for this example. A numerical model to solve the incompressible Navier-Stokes equations is proposed using the OpenFOAM CFD free code. The results of both sets of the simulation were compared with those of the literature, validating the numerical models..