A FINITE ELEMENT FORMULATION FOR THE NAVIER-STOKES PROBLEM / UMA NOVA FORMULAÇÃO DE ELEMENTOS FINITOS PARA O PROBLEMA DE NAVIER-STOKES
AUTOR(ES)
SERGIO LUIZ FREY
FONTE
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia
DATA DE PUBLICAÇÃO
18/12/1991
RESUMO
Stabilized methods for fluid problems are proposed and analysed with particular emphasis to the incompressible Navier-Stokes equations. We Begin in Chapter 2 introducing the balance equations of fluid Mechanics. Next. In Chapter 3, we discuss the numerical difficulties of the Galerkin method in fluids(in the contexto f the Stokes problem) and performance some succeful simulations of creeping flows, employing stabilized formulations. In Chapter 4, we propose a new finite element formulation for the energy equation, or more preciselly for the advective-diffusive model. Taking advantage of new design of the stability parameter T, which permits to add diffusion to advective and diffusive regions of the flow in a different way, we success to obtain a good performance of the new method in flows with very high Péclet numbers (10(2) lass than Pe lessa than 10(6)), as illustred at numerical testes performed. By collecting the Stokes and advective-diffusive experiences,it was possible to propose, analyse and test two new stabilized methods for the transient Navier-Stokes problem. These methods were built in a way to heritage the good characteristics showed by the stabilized methods introduced for the Stokes and adventive-diffusive models. The new methods propoposed have a good performance in high advective flows, besides there is no need to satisfy the Babuska-Brezzi condition. Employing a predictor/multi-corretor algorithm, we were able to simulate accruratly some useful flows(400 less than Re less than 500), such as fluid recirculations.
ASSUNTO(S)
elementos finitos finite elements
