Detailed Two-Dimensional Numerical Analysis of Multiphase Flows / AnÃlise numÃrica detalhada de escoamentos multifÃsicos bidimensionais

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

The mathematical modeling of multiphase ows involves the interaction between deformable and moving geometries with the uid in which they are dispersed (immersed). This kind of interaction is present in many practical applications. A common approach to handle these problems is the so called Front-Tracking/Front-Capturing Hybrid Methods. This methodology consists in separating the problem into two domains: an eulerian domain, which is kept xed and is used to discretize the uid equations of both phases, and a lagrangian domain, which is used to solve the equations of motion of the interface. Since there is no geometric dependence between these two domains, the method can easily handle moving and deformable interfaces that are dispersed in the ow. Following this line of research, the present work aims to capture accurately details of such ows by resolving adequately the relevant physical scales in time and in space. This can be achieved by applying locally rened meshes which adapt dynamically to cover special ow regions, e.g. the vicinity of the uid-uid interfaces. To obtain the required resolution in time, a semi-implicit second order discretization to solve the Navier-Stokes equations is used. The turbulence modeling is introduced in the present work through Large Eddy Simulation. The eciency and robustness of the methodology applied are veried via convergence analysis, as well as with simulations of one-phase and two-phase ows for several Reynolds numbers. The results of two-phase ows, with one bubble and with multiple bubbles, are presented. The results obtained for a single bubble case are compared with Clift s shape diagram (Clift et al., 1978).

ASSUNTO(S)

turbulence adaptive mesh refinement turbulÃncia multigrid-multilevel engenharia mecanica escoamentos multifÃsicos mutltiphase flows multigrid-multinÃvel refinamento local adaptativo

ACESSO AO ARTIGO

Documentos Relacionados