Método Lattice-Boltzmann Aplicado a Aerodinâmica Externa

Abstract

The continuous need for methods dedicated to Computational Fluid Dynamics (CFD) which are numerically stable even when applied to complex geometries, without the need of performing large simplifications and without introducing a large dissipation rate to improve stability, made the Lattice-Boltzmann Method gain prominence in the last years both in the academia and in the aerospace and automotive industries. The present work aims to analyze the capacity of the Lattice-Boltzmann Method to predict the aerodynamics characteristics of flows around circular cylinders for intermediate Reynolds numbers. First, a bibliographic review of the latest studies about the Lattice-Boltzmann method related to the capabilities of simulating and predicting flow characteristics over complex geometries in the turbulent regime and for intermediate Reynolds numbers was performed. In a second moment, the open source code, OpenLB, and the code developed at UFU by the author using Fortran 90 were compared with respect to the capacity of calculating the drag coefficient and the vortex shedding frequency over cylinders for Reynolds 200. The results obtained with the Lattice-Boltzmann method also were compared with the finite volume method, using the software Ansys Fluent®. Finally, both the grid size and the Mach number interference were analyzed.