Multi-scale modeling of dispersed gas-liquid two-phase flow

In this work the concept of multi-scale modeling is demonstrated. The idea of this approach is to use different levels of modeling, each developed to study phenomena at a certain length scale. Information obtained at the level of small length scales can be used to provide closure information at the level of larger length scales. In this work the front tracking model is used to simulate the rise of a single bubble in a quiescent liquid and in a shear field. The results of the front tracking model are used to obtain coefficients for the drag, virtual mass and lift forces that are required in the Euler-Lagrange model used to study the behavior of dispersed gas-liquid flow on a larger scale. Finally, the Euler-Lagrange model, equipped with the correct closure information is used to simulate the flow in a square cross-sectioned bubble column, It is found that the results of the Euler-Lagrange model are in good agreement with experimental data. (C) 2004 Elsevier Ltd. All rights reserved.