CFD analysis of spray propagation and evaporation including wall film formation and spray/film interactions

Addressing the numerical simulation of complex two-phase flows in gas turbi ne combustors, this study features a comprehensive approach to the coupled solution of the interacting flow fields of the gas phase, evaporating fuel spray and evaporating, shear-driven fuel wall film. The gas how and wall-fi lm flow are described in Eulerian coordinates and are both calculated in th e same computational unit. A second, separate program is based on Lagrangia n particle tracking to model spray dispersion and evaporation. To account f or interaction effects, an iterative procedure is applied considering mutua l mass, momentum and energy transfer between the three flow regimes. For a realistic modeling of spray/wall and spray/film interaction, the droplet-tr ajectory computation comprises a set of droplet-impact models covering a br oad range of impact conditions. The results of a two-phase flow simulation in a schematic LPP combustor premix duct demonstrate the effects of phase i nteraction as well as spray/wall and spray/film interaction. (C) 1999 Elsev ier Science Inc. All rights reserved.