Analysis of dust distribution in silo during axial filling using computational fluid dynamics: Assessment on dust explosion likelihood

• Published in: Process safety and environmental protection 2015-07, Vol.96, p.14-21
• Main Authors: Rani, S.I., Aziz, B.A., Gimbun, J.
• Format: Article
• Language: English
• Subjects: CFD; Computational fluid dynamics; Computer simulation; Dust; Dust concentration; Dust explosion; Explosions; Gas–solid flow; Interpolation; Mathematical models; Silo; Silos; Turbulence
• ISSN: 0957-5820; 1744-3598
• DOI: 10.1016/j.psep.2015.04.003

•CFD prediction of cornstarch dust concentration distribution in silo is presented.•Dust concentration distribution is influenced by the gas flow profiles.•Dust concentration exceeds the LEL value in all axial positions.•Dust explosion is likely to occur at the region away from the centre of the silo.•The silo filling process is susceptible to primary dust explosion. In this study, the dust distribution in a silo during axial filling was modelled using a commercial computational fluid dynamics (CFD) code. The work focused on the dust concentration distribution in the silo, for evaluating the likelihood of a dust explosion in the silo. The simulation was conducted using a combination of renormalized (RNG) k-epsilon and discrete phase models, with standard pressure interpolation and a second order upwind scheme. The predicted dust concentration distribution showed a good agreement with experimental data adopted from the literature. It was found that the dust concentration distribution was influenced by mean velocity and turbulence flow. The simulation results suggest that the cornstarch concentration inside the silo was always above the lower explosion limit (LEL), hence requiring a mitigating action or a control system to reduce the explosion risk.