Abstract
This article introduces a computational tool for scales resolving simulations of chemically reacting flows applicable to moderately complex geometries and relevant operating conditions. The advantage of the presented methodology is to retain finite rate chemistry with single step chemical kinetic mechanism coupled with detailed transport to solve for turbulence flow scales, both integral and Kolmogorov scales, as well as flame scales. This enables to limit the cost associated with complex chemical mechanisms. The approach is applied here to an atmospheric laboratory-scale configuration to study high-swirled 100% H2/Air fully premixed flame ignition, a key knowledge gap in the literature. This configuration includes the geometry effects from the swirler that have an essential role in turbulence scale generation driving the flame wrinkling. The computational tool is based on open-source codes, the finite volume OpenFOAM9 solver where detailed transport data from Cantera are integrated. The paper presents the transport model validation, the single-step kinetic mechanism development, the high-performance computing scaling study, the premixed turbulent combustion regime assessment, the geometry, the mesh, and the numerical settings. The non-reacting flowfield and ignition transient sequence numerical results obtained are discussed. Key non-reacting establishing swirling flow features, inner recirculation zone and swirling jet, are captured. The ignition method strategy is devised from 1D premixed flame ignitions tests. It is next applied to the 3D configuration to ignite the premixture. This provides a computational capability to assess multiple ignition scenarios to initiate flame propagation.
