Effects of foam alumina porous media on methane/air explosion flames: A combined study of X-ray CT scanning-based image reconstruction and three-dimensional pore-level simulations

Abstract

Excavating the performance and mechanism of porous media on explosion flames is crucial for developing efficient flame arresters. To achieve high-fidelity insights, this study uniquely employs X-ray CT scanning-based image reconstruction to precisely resolve the structural features of foam alumina porous media. By leveraging advanced numerical approaches, specifically the Flamelet Generated Manifold (FGM) combined with Artificial Thickened Flame (ATF) and Large Eddy Simulation (LES), we investigate the effects of pore density, thickness, and location of the foam alumina porous media on methane/air explosion flames. Our findings reveal that an increased pore density and greater thickness of the porous media significantly enhance flame-blocking effects, resulting in prolonged flame propagation duration and reduced propagation speed. Additionally, positioning the porous media farther from the ignition point leads to accelerated flame propagation. A oivotal discovery is that increases in pore density, thickness, and positioning intensify turbulence-flame interactions, which subsequently promote methane/air flame propagation by accelerating the elementary reactions of critical radicals. These results not only lay a foundation for optimizing flame suppression technologies in hazardous environments but also enhance the understanding of the role of porous media in safety–critical applications for explosion flame suppression.