Large-eddy simulation of a full-scale glove box fire

Abstract

Reactive large-eddy simulations (LES) of the stage of peak heat release rate of open atmosphere glove box fires are carried out. To the best of the authors’ knowledge, this is the first time that the LES of such a geometry is reported in the literature. A multi-fuel extension of the eddy-dissipation model (EDM) is used to simulate the combustion of the two distinct solid fuels, PMMA and Polycarbonate, relevant to this configuration. Three increasingly refined grids are considered. All of them lead to temperature values that are in good agreement with experimental data, and similar levels of heat release are obtained inside the glove box. From a more quantitative point of view, only the most refined grid leads to satisfactory values of LES quality criteria. The intermediate grid allows resolving a fraction of the inertial range dynamics, while the solution obtained on the coarsest grid exhibits very large turbulent structures with characteristic sizes of the order of the integral length scale. The analysis confirms that the choice of the grid cell size has a significant influence on the description of the local flow hydrodynamics, the location and thickness of the reactive zones.