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Hydrogen-air deflagrations: Vent sizing correlation for low-strength equipment and buildings

Molkov, Vladimir and Bragin, Maxim (2015) Hydrogen-air deflagrations: Vent sizing correlation for low-strength equipment and buildings. International Journal of Hydrogen Energy, 40 (2). pp. 1256-1266. [Journal article]

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DOI: 10.1016/j.ijhydene.2014.11.067

Abstract

This paper aims to improve prediction capability of the vent sizing correlation presented inthe form of functional dependence of the dimensionless deflagration overpressure on theturbulent Bradley number similar to our previous studies. The correlation is essentiallyupgraded based on recent advancements in understanding and modelling of combustionphenomena relevant to hydrogeneair vented deflagrations and unique large-scale testscarried out by different research groups. The focus is on hydrogeneair deflagrations inlow-strength equipment and buildings when the reduced pressure is accepted to be below0.1 MPa. The combustion phenomena accounted for by the correlation include: turbulencegenerated by the flame front itself; leading point mechanism stemming from the preferentialdiffusion of hydrogen in air in stretched flames; growth of the fractal area of theturbulent flame surface; initial turbulence in the flammable mixture; as well as effects ofenclosure aspect ratio and presence of obstacles. The correlation is validated against thewidest range of experimental conditions available to date (76 experimental points). Thevalidation covers a wide range of test conditions: different shape enclosures of volume upto 120 m3; initially quiescent and turbulent hydrogeneair mixtures; hydrogen concentrationin air from 6% to 30% by volume; ignition source location at enclosure centre, near andfar from a vent; empty enclosures and enclosures with obstacles.

Item Type:Journal article
Keywords:Hydrogen, Vented deflagration, Experimental data, Correlation, Validation
Faculties and Schools:Faculty of Art, Design and the Built Environment
Faculty of Art, Design and the Built Environment > School of the Built Environment
Research Institutes and Groups:Built Environment Research Institute
Built Environment Research Institute > Hydrogen Safety Engineering and Research Centre (HySAFER)
ID Code:31619
Deposited By: Professor Vladimir Molkov
Deposited On:19 May 2015 08:55
Last Modified:20 Oct 2016 13:23

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