Parallel computation of two-phase flows using the immiscible lattice gas

Abstract

Two-phase flow phenomena are complicated and difficult to simulate numerically since two-phase flows have interfaces of phases. Numerical techniques for simulating two-phase flows with interfaces have recently progressed significantly. Two types of numerical methods have been developed and applied: a continuous fluid approach, in which partial differential equations describing fluid motion are solved, and a discrete particle approach, in which motions of fluid particles or molecules are calculated. It is necessary in a continuous fluid approach to model the coalescence and disruption of the interface. In this chapter, the two-dimensional two-phase flow simulation code based on the immiscible lattice gas, which is one of the discrete methods using particles to simulate two-phase flows is developed and parallelized using the MPI library. Parallel computations are performed on a workstation cluster to study the rising bubble in a static fluid, the phase separation in a Couette flow, and the mixing of two phases in a cavity flow. The interfacial area concentration is evaluated numerically, and its dependencies on the average density, wall speed, and region size are discussed.