| Popis: |
The numerical simulation of immiscible multiphase flow problems, particularly including drops and bubbles, is very important in many applications, and performing accurate, robust and efficient numerical computations has been the object of numerous research and simulation projects for many years. One of the main challenges for the underlying numerical methods – besides the fact that the computational simulation of the incompressible Navier–Stokes equations is challenging by itself – is that the position of the moving interface between two fluids is unknown and must be determined as part of the boundary value problem to be solved. In this contribution, we provide a compact description of state-of-the-art numerical solvers for such multiphase flow problems, namely interface tracking and interface capturing methods. It is demonstrated that corresponding discretization and solution approaches which are based on Finite Element and Discrete Projection methods for the Navier–Stokes equations, combined with corresponding numerical tools for both interface capturing, resp., tracking approaches, lead to robust, accurate, flexible, and efficient simulation tools. Moreover, we present several numerical test cases of benchmarking type which first of all shall help to evaluate the quality of the underlying flow solvers. In particular, we describe the settings for a quantitative 3D Rising Bubble benchmark which can be used for ‘simple’ validation and evaluation of multiphase CFD codes without the necessity of complex postprocessing operations. Finally, we also provide numerical reference values for a ‘Taylor bubble’ setting, and we show simulation results of a reactive Taylor bubble flow in the framework of estimating reaction parameters to match corresponding experimentally obtained results. All reference benchmark quantities can be downloaded from www.featflow.de . |
