Finite Volume Simulation of an Airlift Loop Reactor With Coupled Algebraic Multigrid

An efficient algorithm for solving the equations of multi-phase flow has been developed and implemented in the software CFX-5. The motivation for this method is to obtain scalable behaviour for solving industrial multiphase flow problems. This is achieved using a finite volume discretization of the equations on unstructured meshes, preserving important inter-equation coupling at the algebraic level, and solving the algebraic equations using an efficient multigrid solver. The method also features a high resolution advection scheme for the volume fraction equations, which is particularly important for obtaining accurate solutions on tetrahedral meshes. The algorithm is also parallelized so that fast turn-around times can be achieved. The method is validated for an Enichem airlift loop reactor studied in an ADMIRE project. The results compare well with experimental data and with previous CFX-4 calculations. Solutions are obtained in the same number of iterations independent of the mesh size and with near-linear parallel speedup.