Numerical simulation of two-phase flow in combustion chambers

Abstract

The purpose of this paper is to describe a new approach in which one uses different kinds of post processing to obtain, from 2D or 3D computation codes, the representation of internal flow inside a combustion chamber as an association of elementary reactors (well stirred, plug flow...) To reach this goal and, in order to test this method, different computation codes are used for the gas phase description: mean flow computation or unsteady codes like 'R.V.M.' (Random Vortex Method) or 'F.C.T.' (Flux corrected transport) - For the liquid phase behaviour, we use to kinds of Lagrangian transport schemes: one purely deterministic is linked to the mean gas flow computation, the second one provides individual instantaneous trajectories. These various approaches are used for two kinds of 2D geometries: the backward facing step and a simplified afterburner geometry. Examples of residence time computations are presented for the liquid and gas phases and the effect of unsteady flow and drop sizes are demonstrated by experimental comparisons.