CFD model of dust unsteady flame propagation in the 20 L bomb

Abstract

The development of computational fluid dynamics (CFD) models for dust unsteady flame propagation presents a major challenge, particularly in the selection of a suitable combustion sub-model. Particle-based Lagrangian models provide a detailed description of the thermochemical conversion of fuels, but are often computationally expensive and impractical for most industrial applications. Premixed combustion models, on the other hand, treat the air/dust mixture as a single homogeneous fluid, with the chemical reactions occurring predominantly in the gas phase. These models are suitable for the simulation of biomass dust explosions, where the rapid release and combustion of volatile gases dominates the flame propagation. In this paper, a CFD model of unsteady flame propagation of biomass is developed using OpenFOAM. The model relies on a novel equation previously developed for the evaluation of the laminar flame speed of air/dust mixture inspired by the Mallard-Le Chatelier theory. Model validation is performed by comparing CFD simulation results with the literature data on cornstarch dust explosions in a 20 L bomb.