Unsteady 3-D RANS simulations of dust explosion in a fan stirred explosion vessel using an open source code
2020 (English)In: Journal of Loss Prevention in the Process Industries, ISSN 0950-4230, E-ISSN 1873-3352, Vol. 67, article id 104237Article in journal (Refereed) Published
Abstract [en]
Dust explosion is a constant threat to industries which deal with combustible powders such as woodworking, metal processing, food and feed, pharmaceuticals and additive industries. The current standards regarding dust explosion venting protecting systems, such as EN 14491 (2012) and NFPA 68 (2018), are based on empirical correlations and neglect effects due to complex geometry. Such a simplification may lead to failure in estimating explosion overpressure, thus, increasing risk for injuries and even fatalities at workplaces. Therefore, there is a strong need for a numerical tool for designing explosion protecting systems. This work aims at contributing to the development of such a tool by (i) implementing a premixed turbulent combustion model into OpenFOAM, (ii) verifying the implementation using benchmark analytical solutions, and (iii) validating the numerical platform against experimental data on cornflour dust explosion in a fan-stirred explosion vessel, obtained by Bradley et al. (1989a) under well-controlled laboratory conditions. For this purpose, the so-called Flame Speed Closure model of the influence of turbulence on premixed combustion is adapted and implemented into OpenFOAM. The implementation of the model is verified using exact and approximate analytical solutions for statistically one-dimensional planar and spherical turbulent flames, respectively. The developed numerical platform is applied to unsteady three-dimensional Reynolds Averaged Navier-Stokes simulations of the aforementioned experiments. The results show that the major trends, i.e. (i) a linear increase in an apparent turbulent flame speed St,b with an increase in the root mean square (rms) turbulent velocity u' and (ii) and an increase in St,b with an increase in the mean flame radius, are qualitatively predicted. Furthermore, the measured and computed dependencies of St,b(u') agree quantitatively under conditions of weak and moderate turbulence. © 2020
Place, publisher, year, edition, pages
Elsevier Ltd , 2020. Vol. 67, article id 104237
Keywords [en]
Computational Fluid Dynamics, Dust explosion, Modelling, Open source, OpenFOAM, Premixed turbulent combustion, Analytical models, Codes (symbols), Combustion, Dust, Flame research, Navier Stokes equations, Open source software, Open systems, Risk perception, Turbulence, Approximate analytical solutions, Controlled laboratories, Empirical correlations, Explosion overpressure, Premixed combustion, Reynolds-averaged navier-stokes simulations, Turbulent flame speed, Explosions
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-46788DOI: 10.1016/j.jlp.2020.104237Scopus ID: 2-s2.0-85088945860OAI: oai:DiVA.org:ri-46788DiVA, id: diva2:1460643
Note
Funding details: 180028; Funding text 1: The authors would like to acknowledge AFA-Försäkring for financial support of this project (grant number 180028 ).
2020-08-242020-08-242024-04-09Bibliographically approved