Dynamics of Hydrogen Flame Self-Extinction in a Vented Enclosure

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The phenomenon of hydrogen jet flame self-extinction in an enclosure with one vent is simulated numerically for the first time. The eddy dissipation concept model of combustion with a full chemistry scheme is applied along with the renormalization group theory for turbulence modelling within RANS approach. The analysis of temporary profiles of temperature and species (hydrogen, oxygen, hydroxyl, water) concentrations in the numerical experiment, as well as velocity through the vent, shed a light on the dynamics of under-ventilated hydrogen fire the self-extinction process in the enclosure with one horizontal vent located under the ceiling. The self-extinction is a process rather than an instance. The analysis of under-ventilated fire based on parameters averaged throughout the enclosure can give a good indication of the moment when combustion essentially reduces due to lack of oxygen, yet it can mislead in interpretation of the moment when combustion is fully ceased. It is shown that the pressure peaking phenomenon is more pronounced for jet fire compared to unignited release from the same source (by factor 100 in this particular experiment, i.e. about 300 Pa and 3 Pa respectively). The separation distances from the enclosure are estimated for this indoor fire scenario. The maximum length of hot gases jet escaping the enclosure was about twice of the enclosure size. The simulations demonstrated a complex flow dynamics through the vent in both directions during the self-extinction process. This is thought due to the interaction between processes of sustained hydrogen leak, combustion, and heat transfer to the enclosure walls. The separation distances from the enclosure are estimated for indoor fire scenario.
LanguageEnglish
Title of host publicationUnknown Host Publication
Number of pages10
DOIs
Publication statusPublished - 10 May 2013
EventSeventh International Seminar on Fire & Explosion Hazards (ISFEH7) - Providence, RI, USA.
Duration: 10 May 2013 → …

Conference

ConferenceSeventh International Seminar on Fire & Explosion Hazards (ISFEH7)
Period10/05/13 → …

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Enclosures
Hydrogen
Vents
Fires
Group theory
Oxygen
Ceilings
Turbulence
Experiments
Heat transfer
Gases
Water

Cite this

@inproceedings{708cf62e10224348883c7772105a59af,
title = "Dynamics of Hydrogen Flame Self-Extinction in a Vented Enclosure",
abstract = "The phenomenon of hydrogen jet flame self-extinction in an enclosure with one vent is simulated numerically for the first time. The eddy dissipation concept model of combustion with a full chemistry scheme is applied along with the renormalization group theory for turbulence modelling within RANS approach. The analysis of temporary profiles of temperature and species (hydrogen, oxygen, hydroxyl, water) concentrations in the numerical experiment, as well as velocity through the vent, shed a light on the dynamics of under-ventilated hydrogen fire the self-extinction process in the enclosure with one horizontal vent located under the ceiling. The self-extinction is a process rather than an instance. The analysis of under-ventilated fire based on parameters averaged throughout the enclosure can give a good indication of the moment when combustion essentially reduces due to lack of oxygen, yet it can mislead in interpretation of the moment when combustion is fully ceased. It is shown that the pressure peaking phenomenon is more pronounced for jet fire compared to unignited release from the same source (by factor 100 in this particular experiment, i.e. about 300 Pa and 3 Pa respectively). The separation distances from the enclosure are estimated for this indoor fire scenario. The maximum length of hot gases jet escaping the enclosure was about twice of the enclosure size. The simulations demonstrated a complex flow dynamics through the vent in both directions during the self-extinction process. This is thought due to the interaction between processes of sustained hydrogen leak, combustion, and heat transfer to the enclosure walls. The separation distances from the enclosure are estimated for indoor fire scenario.",
author = "Vladimir Molkov and Volodymyr Shentsov and Sile Brennan and Dmitriy Makarov",
year = "2013",
month = "5",
day = "10",
doi = "10.3850/978-981-07-5936-0_14-03",
language = "English",
booktitle = "Unknown Host Publication",

}

Molkov, V, Shentsov, V, Brennan, S & Makarov, D 2013, Dynamics of Hydrogen Flame Self-Extinction in a Vented Enclosure. in Unknown Host Publication. Seventh International Seminar on Fire & Explosion Hazards (ISFEH7), 10/05/13. https://doi.org/10.3850/978-981-07-5936-0_14-03

Dynamics of Hydrogen Flame Self-Extinction in a Vented Enclosure. / Molkov, Vladimir; Shentsov, Volodymyr; Brennan, Sile; Makarov, Dmitriy.

Unknown Host Publication. 2013.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

TY - GEN

T1 - Dynamics of Hydrogen Flame Self-Extinction in a Vented Enclosure

AU - Molkov, Vladimir

AU - Shentsov, Volodymyr

AU - Brennan, Sile

AU - Makarov, Dmitriy

PY - 2013/5/10

Y1 - 2013/5/10

N2 - The phenomenon of hydrogen jet flame self-extinction in an enclosure with one vent is simulated numerically for the first time. The eddy dissipation concept model of combustion with a full chemistry scheme is applied along with the renormalization group theory for turbulence modelling within RANS approach. The analysis of temporary profiles of temperature and species (hydrogen, oxygen, hydroxyl, water) concentrations in the numerical experiment, as well as velocity through the vent, shed a light on the dynamics of under-ventilated hydrogen fire the self-extinction process in the enclosure with one horizontal vent located under the ceiling. The self-extinction is a process rather than an instance. The analysis of under-ventilated fire based on parameters averaged throughout the enclosure can give a good indication of the moment when combustion essentially reduces due to lack of oxygen, yet it can mislead in interpretation of the moment when combustion is fully ceased. It is shown that the pressure peaking phenomenon is more pronounced for jet fire compared to unignited release from the same source (by factor 100 in this particular experiment, i.e. about 300 Pa and 3 Pa respectively). The separation distances from the enclosure are estimated for this indoor fire scenario. The maximum length of hot gases jet escaping the enclosure was about twice of the enclosure size. The simulations demonstrated a complex flow dynamics through the vent in both directions during the self-extinction process. This is thought due to the interaction between processes of sustained hydrogen leak, combustion, and heat transfer to the enclosure walls. The separation distances from the enclosure are estimated for indoor fire scenario.

AB - The phenomenon of hydrogen jet flame self-extinction in an enclosure with one vent is simulated numerically for the first time. The eddy dissipation concept model of combustion with a full chemistry scheme is applied along with the renormalization group theory for turbulence modelling within RANS approach. The analysis of temporary profiles of temperature and species (hydrogen, oxygen, hydroxyl, water) concentrations in the numerical experiment, as well as velocity through the vent, shed a light on the dynamics of under-ventilated hydrogen fire the self-extinction process in the enclosure with one horizontal vent located under the ceiling. The self-extinction is a process rather than an instance. The analysis of under-ventilated fire based on parameters averaged throughout the enclosure can give a good indication of the moment when combustion essentially reduces due to lack of oxygen, yet it can mislead in interpretation of the moment when combustion is fully ceased. It is shown that the pressure peaking phenomenon is more pronounced for jet fire compared to unignited release from the same source (by factor 100 in this particular experiment, i.e. about 300 Pa and 3 Pa respectively). The separation distances from the enclosure are estimated for this indoor fire scenario. The maximum length of hot gases jet escaping the enclosure was about twice of the enclosure size. The simulations demonstrated a complex flow dynamics through the vent in both directions during the self-extinction process. This is thought due to the interaction between processes of sustained hydrogen leak, combustion, and heat transfer to the enclosure walls. The separation distances from the enclosure are estimated for indoor fire scenario.

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DO - 10.3850/978-981-07-5936-0_14-03

M3 - Conference contribution

BT - Unknown Host Publication

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