Phenomenological model of soot production inside a non-buoyant laminar diffusion flame

Legros, Guillaume; Torero, José L.

doi:10.1016/j.proci.2014.05.038

Cited by 22 publications

(15 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Conversely, in microgravity, radiative transfer -partially directed to the coating -is amplified, especially due to increased residence times in flames [29] and enhanced soot production [30]. As a result, spreading flames established in microgravity may interact at longer length scales that at normal gravity.…”

Section: Iii3 Optical Diagnostics and Image Processingmentioning

confidence: 99%

Fire safety in space – Investigating flame spread interaction over wires

et al. 2016

View full text Add to dashboard Cite

In order to reduce the uncertainty and risk in the design of spacecraft fire safety systems, a new experimental rig that allows the study of concomitant flames spreading over the coating of parallel cylindrical wires in an air flow parallel to the wires in microgravity has been developed. The parabolic flight experiments were conducted at small length-and timescales, i.e. typically over 10 cm long samples for up to 20 seconds. For the first time, the influence of neighboring spread on the mass burning rate was assessed in microgravity. The observations are contrasted with the influence characterized in normal gravity. The experimental results are expected to deliver meaningful guidelines for future, planned experiments at a larger scale.Arising from the current results, the issue of the potential interaction among spreading flames also needs to be carefully investigated as this interaction plays a major role in realistic fire scenarios, and therefore on the design of the strategies that would allow the control of such a fire. Once buoyancy has been removed, the characteristic length and time scales of the different modes of heat and mass transfer are modified. For this reason, interaction among spreading flames may be revealed in microgravity, while it would not at normal gravity, or vice versa. Furthermore, the interaction may lead to an enhanced spread rate when mutual preheating dominates or, conversely, a reduced spread rate when oxidizer flow vitiation is predominant.In more general terms, the current study supports both the SAFFIRE and the FLARE projects, which are large projects with international scientific teams. First, material samples will be tested in a series of flight experiments (SAFFIRE 1-3) conducted in Cygnus vehicles after they have undocked from the ISS. These experiments will allow the study of ignition and possible flame spread in real spacecraft conditions, i.e. over real length scale samples within real time scales. Second, concomitant research conducted within the FLARE project is dedicated to the assessment of new standard tests for materials that a spacecraft can be composed of. Finally, these tests aim to define the ambient conditions that will mitigate and potentially prohibit the flame spread in microgravity over the material studied.

show abstract

Section: Iii3 Optical Diagnostics and Image Processingmentioning

confidence: 99%

Fire safety in space – Investigating flame spread interaction over wires

et al. 2016

View full text Add to dashboard Cite

show abstract

“…As a result, the global residence time inside the flame is increased when increasing the magnitude of the upward r(B 2 ). This e↵ect that can be considered similar to a decrease in g magnitude then tends to locally promote soot formation [26]. In addition, the magnetic force will also reduce the velocity of the fresh oxidizer flow.…”

mentioning

confidence: 93%

Dual magnetic effects on soot production in partially premixed flames

Bonnety

Pitsch

Gomez

et al. 2017

Proceedings of the Combustion Institute

Self Cite

View full text Add to dashboard Cite

The present paper further explores the potential of the gradient of the square of the magnetic flux density (r(B 2 )) to control the soot production in flames. systematically leads to an increase in soot production, while this magnetic gradient can induce an overall reduction in soot production in some partiallyPreprint submitted to Elsevier May 17, 2016 premixed flames. This original reversal is attributed to a switch of the magnetic force direction. As a result, this supplementary force can induce an increase or a decrease of the residence time in the rich region of a partially premixed flame, depending mainly on the fields of oxygen mole fraction and temperature in this region. In conjunction with more elaborated magnetic fields, these opposite trends may contribute to strategies for the control of soot production.

show abstract

“…To track the soot volume fraction distribution, the Laser Extinction Method (LEM) [23,24] is applied, providing two-dimensional soot volume fraction fields with both fine temporal and spatial resolutions. The arrangement of the optical diagnostics to conduct LEM specifically through a flame located in the electromagnet is shown in Fig.…”

Section: Experimental Observations and Proceduresmentioning

confidence: 99%

Combustion instability mitigation by magnetic fields

et al. 2017

View full text Add to dashboard Cite

The present interdisciplinary study combines electromagnetics and combustion to unveil an original and basic experiment displaying a spontaneous flame instability that is mitigated as the non-premixed sooting flame experiences a magnetic perturbation. This magnetic instability mitigation is reproduced by direct numerical simulations to be further elucidated by a flow stability analysis. A key role in the stabilization process is attributed to the momentum and thermochemistry coupling that the magnetic force, acting mainly on paramagnetic oxygen, contributes to sustain. The spatial local stability analysis based on the numerical simulations shows that the magnetic field tends to reduce the growth rates of small flame perturbations.

show abstract

Phenomenological model of soot production inside a non-buoyant laminar diffusion flame

Cited by 22 publications

References 26 publications

Fire safety in space – Investigating flame spread interaction over wires

Fire safety in space – Investigating flame spread interaction over wires

Dual magnetic effects on soot production in partially premixed flames

Combustion instability mitigation by magnetic fields

Contact Info

Product

Resources

About