Gatsonides, JG, Andrews, GE, Phylaktou, HN et al. (1 more author) (2015) Fluorinated halon replacement agents in explosion inerting. Journal of Loss Prevention in the Process Industries, 36. pp. 544-552. ISSN 0950-4230
Abstract
The US Federal Aviation Administration (FAA) observed during explosion tests that at a low concentration of agent, some candidate halon replacement agents increased the explosion severity instead of mitigating the event. At UTC Aerospace Systems a test program was developed to assess the behaviour of alternative agents at values below inerting concentration. Two agents were selected, C2HF5 (Penta- fluoroethane, HFC-125) and C6F12O (FK-5-1-12, Novec™1230). Baseline tests were performed with unsuppressed C3H8 (propane)/air mixtures and C3H8/air mixtures with CF3Br (Halon 1301) and N2 (nitrogen). Using CF3Br or N2 at below inerting concentrations mitigated the explosion. C2HF5 was tested against C3H8 at stoichiometric (4 vol%) and lower explosion limit (LEL) (2 vol%). Against 4 vol% C3H8 the combustion was mitigated, proportional to agent concentration; however, low concentrations of C2HF5 with 2 vol% C3H8 enhanced the explosion. Tests with N2 against a volatile mixture of C3H8 with C2HF5 showed that N2 mitigated the events. Final tests were performed with low concentrations of C6F12O against C3H8/air mixtures. This showed similar behaviour to that observed with the C2HF5 tests. Normally during qualification tests for new agents the stoichiometric concentration of a fuel is deemed to be the worst case scenario and the baseline against which agents are tested. The above described test results show that this assumption may need to be reconsidered. This work shows that contrary to common assumption the agents investigated are unlikely to have acted chemically at the flame front, but most likely, mainly cooled the flame and changed the stoichiometry, i.e. the ratio of components of the flammable mixture.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | (c) 2015, Elsevier. This is an author produced version of a paper published in Journal of Loss Prevention in the Process Industries. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | Gaseous suppressants; Clean agents; Inerting; Mitigation; Gas vapour explosions |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) > Energy Research Institute (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 21 Apr 2016 09:31 |
Last Modified: | 15 Jan 2018 22:10 |
Published Version: | http://dx.doi.org/10.1016/j.jlp.2015.03.001 |
Status: | Published |
Publisher: | Elsevier |
Identification Number: | 10.1016/j.jlp.2015.03.001 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:97345 |