Effects of vitiation on the heat release rate in mechanically-ventilated compartment fires

Melis, S.; Audouin, L.

doi:10.3801/iafss.fss.9-931

Cited by 29 publications

(29 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is therefore to be considered as a limitation of the present model. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 Finally, it is noted that the temperatures measured in [13] remained below 475 K [14]. Knowing that the vaporization temperature of HTP is 461 K, one can conclude that the thermal feedback effect in [13] is negligible, if not inexistent.…”

Section: Resultsmentioning

confidence: 97%

“…It is noteworthy that Melis et al [14] examined additional experimental data (not shown here) where the air inlet was placed at a low position. They concluded that, in such configuration, the available oxygen near the flame base is significantly higher than the mean oxygen concentration, inducing therefore a behaviour more similar to naturally-ventilated fires.…”

Section: Resultsmentioning

confidence: 99%

“…1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 (a)Top view of the fire room (b) Side view of the fire room Figure 3. Experimental set-up used in [13][14].…”

Section: Configurationmentioning

confidence: 99%

“…[1][2][3][4][5][6][7][8][9][10][11]), whereas fewer studies have focused on mechanically-ventilated room fires (e.g. [12][13][14][15][16][17]). The latter configuration is particularly relevant for the nuclear industry where compartments are generally sealed from one another and connected through a ventilation network.…”

Section: Introductionmentioning

confidence: 99%

“…An analysis of the experimental data provided in [13] has been performed in [14] by applying the well-stirred reactor approach developed in [7] in quasi-steady state conditions. The analysis relied on the assumption that "the room temperatures do not cause significant additional heat flux to the fuel surface and therefore additional pyrolysis".…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Assessment of the Burning Rate of Liquid Fuels in Confined and Mechanically-Ventilated Compartments using a Well-Stirred Reactor Approach

Beji

Merci

2014

Fire Technol

View full text Add to dashboard Cite

The objective of this work is to provide a 'support tool' to assess the burning rate of a pool fire in a well-confined and mechanically-ventilated room using a single-zone model based on conservation equations for mass, energy and oxygen concentration. Such configurations are particularly relevant for nuclear facilities where compartments are generally sealed from one another and connected through a ventilation network. The burning rates are substantially affected by the dynamic interaction between the fuel mass loss rate and the rate of air supplied by mechanical ventilation. The fuel mass loss rate is controlled by (i) the amount of oxygen available in the room (i.e. vitiation oxygen effect) and (ii) the thermal enhancement via radiative feedback from the hot gas to the fuel surface. The steady-state burning rate is determined by the 'interplay' and balance between the limiting effect of oxygen vitiation and the enhancing effect of radiative feedback. An extensive sensitivity study over a wide range of fuel areas and mechanical ventilation rates shows that a maximum burning rate may be obtained.

show abstract

Section: Resultsmentioning

confidence: 97%

Section: Resultsmentioning

confidence: 99%

Section: Configurationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Assessment of the Burning Rate of Liquid Fuels in Confined and Mechanically-Ventilated Compartments using a Well-Stirred Reactor Approach

Beji

Merci

2014

Fire Technol

View full text Add to dashboard Cite

show abstract

Experimental determination of fire heat release rate with OC and CDG calorimetry for ventilated compartments fire scenario

2013

Self Cite

View full text Add to dashboard Cite

This research deals with the experimental determination of the heat release rate (HRR) of fires in mechanically ventilated compartments based on oxygen consumption (OC) and carbon dioxide generation (CDG) calorimetry. It proposes formulations for fire in force-ventilated compartments on the same basis as the relations established for hood calorimetry in an open atmosphere but considering inertia and unsteady behavior of the fire via the time variation mass of O 2 and CO 2 in the compartment. The value of the new formulations of HRR has been tested in two series of propane gas fire experiments performed in a large-scale facility. The first series involves a fire scenario with one compartment, and the second series, a fire scenario with three compartments connected to each other by doorways. In the first test series, the OC and CDG formulations for HRR are assessed. In the second test series, the OC and CDG formulations are presented with two approaches to definition of the control volume: approach involving three rooms and the flow rate in the ventilation network and approach involving only the fire room and the flow rate through the doorways. On the basis of the fire experiments considered, the most accurate method (accuracy to within 10%) for determining the HRR is the CDG formulation with approach for the control volume without considering the flow rates at the doorways. This analysis points out the different features of each method (OC and CDG) and thoroughly discusses their advantages and drawbacks. The overall analysis allows guidelines to be formulated for fire HRR calculation in confined and ventilated compartments.

show abstract

Characterization of highly under‐ventilated fires using the cone calorimeter

et al. 2015

View full text Add to dashboard Cite

Summary The cone calorimeter, originally designed with an ‘open configuration‘, may be used in combination with a closed‐combustion chamber in order to test specimens in oxygen‐depleted atmospheres (air vitiation effect) or in fuel‐rich combustion (ventilation effect). However, highly under‐ventilated conditions are not achievable, as a consequence of an overconsumption of oxygen due to the incomplete confinement of the flame and imperfections in the air tightness of the combustion volume. In this work, these issues were solved by lowering the combustion zone, in order to fit a 600 mm chimney on the top of the controlled‐atmosphere chamber, and further improving the sealing of the whole setup. n‐Heptane was used as a reference fuel, and its combustion properties were determined in under‐ventilated conditions. The yields of main combustion species correlated well with the global equivalence ratio, for values of Φ up to three. The use of a Fourier‐transform infrared spectrometer allowed further refinement of the total unburned‐fraction composition. The relative concentration of species like methane, ethylene, or acetylene was shown to be relatively constant over the range of under‐ventilated conditions. Copyright © 2015 John Wiley & Sons, Ltd.

show abstract

Effects of vitiation on the heat release rate in mechanically-ventilated compartment fires

Cited by 29 publications

References 12 publications

Assessment of the Burning Rate of Liquid Fuels in Confined and Mechanically-Ventilated Compartments using a Well-Stirred Reactor Approach

Assessment of the Burning Rate of Liquid Fuels in Confined and Mechanically-Ventilated Compartments using a Well-Stirred Reactor Approach

Experimental determination of fire heat release rate with OC and CDG calorimetry for ventilated compartments fire scenario

Characterization of highly under‐ventilated fires using the cone calorimeter

Contact Info

Product

Resources

About