Influence of porous walls on flame front perturbations in hydrogen-air mixtures

Головастов, С. В.; Bivol, G. Yu.; Golub, V. V.

doi:10.1016/j.ijhydene.2020.10.028

Cited by 11 publications

(7 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here, L = 20 mm is the minimal width of the diagnostic section and η is the viscosity of the gas mixture. The method for determining the viscosity of hydrogen-air mixtures and their characteristic numerical values (η = 17.7 × 10 −6 -18.3 × 10 −6 Pa × s) are presented in [33]. The characteristic Reynolds numbers for the channel are equal to 1.3 × 10 4 for the stoichiometric mixture and 1.4 × 10 3 for ER = 0.4, respectively.…”

Section: Resultsmentioning

confidence: 99%

“…Taking into account the velocity v fl of the flame front, one can estimate the velocity v of the unburned mixture and the Reynolds number, Re. In this work, the estimation was carried out for the maximum value in a quasi-one-dimensional isobaric approximation [33,37]:…”

Section: Resultsmentioning

confidence: 99%

“…The development of hydrodynamic instability is influenced by various factors, in particular, the geometry of the channel has a significant influence, including the structure of the coatings of the internal walls and their shape. As was shown in [33], the presence of porous coatings can affect the flow of the unburned mixture and thereby influence the development of disturbances at the flame front.…”

Section: Introductionmentioning

confidence: 85%

See 2 more Smart Citations

The Formation of a Flame Front in a Hydrogen–Air Mixture during Spark Ignition in a Semi-Open Channel with a Porous Coating

Golovastov,

Bivol,

Kuleshov

et al. 2023

Fire

View full text Add to dashboard Cite

An experimental study of ignition and flame front propagation during spark initiation in a hydrogen–air mixture in a semi-open channel with a porous coating is reported. The bottom surface of the channel was covered with a porous layer made of porous polyurethane or steel wool. The measurements were carried out for a stoichiometric mixture (equivalence ratio ER = 1.0) and for a lean mixture (ER = 0.4) of hydrogen with air, where ER is the molar excess of hydrogen. The flame front was recorded with a high-speed camera using the shadow method. Depending on the pore size, the velocity of the flame front and the sizes of disturbances generated on the surface of the flame front were determined. Qualitative features of the deflagration flame front at ER = 0.4, consisting of disturbances resembling small balls of flame, were discovered. The sizes of these disturbances significantly exceed the analytical values for the Darrieus–Landau instability. The effect of coatings made of porous polyurethane or steel wool is compared with the results obtained for an empty smooth channel. Depending on the hydrogen concentration in the hydrogen–air mixture, the velocity of the flame front compared to a smooth channel was three times higher when the channel was covered with steel wool and five times higher when the channel was covered with porous polyurethane.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 85%

See 1 more Smart Citation

The Formation of a Flame Front in a Hydrogen–Air Mixture during Spark Ignition in a Semi-Open Channel with a Porous Coating

Golovastov,

Bivol,

Kuleshov

et al. 2023

Fire

View full text Add to dashboard Cite

show abstract

“…There have been numerous studies on flame stabilization of premixed hydrogen flames [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]. However, the literature discussing flame movement in a semi-controlled manner is rather scarce.…”

Section: Introductionmentioning

confidence: 99%

Dynamic stabilization of a hydrogen premixed flame in a narrow channel

Vance

Scholtissek

Goey

et al. 2023

Combustion and Flame

View full text Add to dashboard Cite

“…Ciccarelli et al [15] further found that orifice plate spacing have a great effect on deflagration propagation velocity. The flame disturbance size in the hydrogen mixture increases with the increase of the pore size of the porous material of the channel wall [16]. Song et al [17] proved that mesh aluminum alloys (playing roles as multiple obstacles) had a dual promoting/inhibiting effect on the deflagration of hydrogen-air mixtures.…”

Section: Introductionmentioning

confidence: 99%

Promoting of foam copper with chaotic distributed pores on the deflagration of premixed hydrogen-air flame in the tube

Long

Duan

et al. 2022

THERM SCI

View full text Add to dashboard Cite

The deflagration flame of stoichiometric hydrogen-air mixtures is studied in this paper. Combined with the foam copper structure, the deflagration characteristic is analyzed in this paper. The experimental results show that the foam copper can improve the flow instability at the flame front and the degree of turbulence in the propagation process, the flame propagates more rapidly in turbulence state, and the number of stages of flame morphology during the propagation process increases. The classic ?tulip? flame can be transformed into a distorted ?tulip? flame and a fractal ?tulip? flame before it collapses. When the flame passes through the foam copper, the flame front velocity increases as the number of structural layers increases. The flame front velocity propagates at supersonic speed through the accumulation of three layers of foam copper. The instability of overpressure in the propagation process will cause oscillation. More layers of the structure, the oscillation frequency, and the amplitude of the overpressure are increased significantly. Foam copper structure has a reverse action on overpressure. When the overpressure value is low in the early stage, the structure promotes the propagation, but the overpressure value is large in the later stage, the structure has a blocking effect.

show abstract

Influence of porous walls on flame front perturbations in hydrogen-air mixtures

Cited by 11 publications

References 50 publications

The Formation of a Flame Front in a Hydrogen–Air Mixture during Spark Ignition in a Semi-Open Channel with a Porous Coating

The Formation of a Flame Front in a Hydrogen–Air Mixture during Spark Ignition in a Semi-Open Channel with a Porous Coating

Dynamic stabilization of a hydrogen premixed flame in a narrow channel

Promoting of foam copper with chaotic distributed pores on the deflagration of premixed hydrogen-air flame in the tube

Contact Info

Product

Resources

About