A numerical analysis of multi-dimensional iron flame propagation using boundary-layer resolved simulations
New publication at STFS
06.05.2024 von Prof. Dr.-Ing. Christian
As a carbon-free energy carrier, there is a great requirement for exploring the fundamental and application aspects of iron combustion. Due to the non-volatile nature of its combustion, iron dust flame can propagate in a continuous (gas like) or a discrete (percolation wave) mode. The underlying heat and mass transfer mechanisms determine the mode and speed of the flame propagation. Such mechanisms depend on a wide variety of effects such as curvature, stretch, heat loss, polydispersity etc and their outcome could influence flame stabilization. This necessitates the usage of detailed boundary-layer resolved simulations for studying the essential physics in order to understand the problem.
While previous works have focused on flat flame propagation using such simulations, in this work we extend the domain of knowledge by simulating a curved iron flame with up to 900 resolved particles. This is a first step in unravelling the complex nature of iron dust flame propagation and provide a base understanding of how the flat and the curved flame propagation could differ. The key findings of this paper are:
- Despite different particles spacings, a curved flame propagates with a single speed in the continuous mode of flame propagation.
- Redistribution of oxygen locally allows such a continuous flame propagation with particles burning richer/leaner compared to corresponding particles distances in the flat flame propagation.
- Curved dust flames propagate in a narrower range of equivalence ratio than flat flames due to excessive heat required to make the flame propagate at leaner stoichiometries with larger particle distances.
Paper available in: FUEL (open-access)
