Simulações computacionais de escoamentos sobre aerofólios e asas usando software livre

Abstract

Wings operate with maximum efficiency when they achieve the highest ratio between the lift coefficient and the drag coefficient. These coefficients are dimensionless numbers related to the interactions exerted by a fluid flow on solid objects and are essential for optimizing wing designs as well as for other aerodynamic applications, such as optimizing wind turbines, compressors and hydraulic pumps. The computational approach makes it possible to develop different studies for different aerodynamic profiles at little cost compared to experiments, so it is possible to analyze in detail how a wing behaves under different flow conditions. In order to investigate these coefficients, a geometric model and three-dimensional complex meshes were developed to study air flow over a wing formed by a NACA 4415 profile, with a 10º angle of attack, unit chord length and two different spam lengths. This analysis is conducted with a Reynolds number of 750,000. For this purpose, the OpenFOAM software was chosen, as it is a free, open-source software dedicated to solving Computational Fluid Dynamics (CFD) problems. In addition to OpenFOAM, CAD software was used to generate the geometric model, in this case the wing; the SnappyHexMesh mesh generator, supplied with OpenFOAM itself, and to choose, among those available, the most suitable computational algorithms to carry out the simulations. Specifically, SimpleFOAM was chosen, a classic algorithm that solves the Navier Stokes equations in steady state for incompressible and turbulent flow. The main result obtained is the development of a specific process for carrying out computer simulations of three-dimensional turbulent flows over complex (non-Cartesian) geometries.