The Modes of Gaseous Combustion

Рубцов, Н. М.

doi:10.1007/978-3-319-25933-8

Cited by 29 publications

(4 citation statements)

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“…We also detected molecules HF (ν = 3) at inhibition of natural gas combustion with octadecafluorodecahydronaphthalene ("artificial blood", perfluorodecaline C 10 F 18 ) [26]. The reaction, in which enough energy can be emitted (11,100 cm −1 = 1.38 eV = 37 kcal/mole) to provide vibrational excitation of HF molecules (ν = 3), is almost a thermally neutral reaction [14,26,27]: Since the inhibitor concentration limit of the stoichiometric methane-air mixture is about 1% CF 2 Cl 2 , the intensity of HF emission is indeed rather low to compare with HF intensity at hydrogen combustion in the presence of the same amount of halon.To increase the sensitivity of the technique by means of addition of greater amounts of halon, oxygen mixes instead of air mixes were used.…”

Section: Resultsmentioning

confidence: 94%

“…In addition, there is no reason to consider that atoms H play the leading role in methane oxidation. Really, in the works [13,14] it is assumed that the role of H atoms in hydrocarbon oxidation is not determining one and consists, at least, in participation in longer chains, than at hydrogen oxidation.…”

Section: Introductionmentioning

confidence: 99%

“…Notice that the estimate of a rate constant at room temperature of termination via CF 2 Cl 2 is given in [15]: k (H + CF 2 Cl 2 ) = 5 × 10 12 exp(− 9500/RT) cm 3 mol −1 s −1 . It means that hydrogen atoms react with halon molecules in the primary center of ignition at 1000 K (experimental value of gas temperature in a spark ignition zone [14]); it can provide inhibition [14].…”

Section: Introductionmentioning

confidence: 99%

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The features of combustion of hydrogen and methane in oxygen and air in the presence of difluorodichloromethane additives

Рубцов

Vinogradov²,

Kalinin

et al. 2019

SN Appl. Sci.

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It is shown that the inhibitor limit of ignition of the premixed methane-air mix makes 1 vol% difluorodichloromethane at 1 atm. It means that difluorodichloromethane is an effective inhibitor to prevent undesirable ignition of methane-air mixes at atmospheric pressure. It is experimentally shown that the concentration limits of the initiated combustion known from literature are meaningful only for previously prepared mixes. If the mixes are prepared just before the experiment, then the existence or the lack of ignition is determined by both an order of injection of mixture components, and the geometry of an installation. Therefore, the inhibition with halons can hardly be used to address the challenges of safety in mines. Thus, the influence of gasdynamic factors on the efficiency of inhibition is revealed. It is shown that the active centers of hydrogen and methane combustion determining the development of combustion process have the different chemical nature. Vibrationally excited molecules of hydrogen fluoride (ν = 2, 3) are for the first time detected in the products of combustion of hydrogen and methane in the presence of difluorodichloromethane by means of hyper spectrometers of visible and near infrared spectral range. It can be promising phenomenon in laser chemical applications. It is shown that in methane oxidation, the reaction with difluorodichloromethane leading to the formation of hydrogen fluoride (ν = 2,3) has to include the active center of methane combustion.

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Section: Resultsmentioning

confidence: 94%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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The features of combustion of hydrogen and methane in oxygen and air in the presence of difluorodichloromethane additives

Рубцов

Vinogradov²,

Kalinin

et al. 2019

SN Appl. Sci.

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“…The results indicated that the vortex and air pressure waves existing in the unburned gas were the main factors that caused the flame to spread during the combustion process. Rubtsov et al believed that the instability and turbulence of flame could lead to the acceleration of combustion under the presence of barriers. Moreover, several researchers have simulated the dynamic characteristics of flame propagation under the presence of barriers. − …”

Section: Introductionmentioning

confidence: 99%

Effect of a Perforated Polyethylene Material on Propane–Air Explosion in a Confined Space

Qiao

Long³

2022

ACS Omega

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In this study, the effect of polyethylene barriers with different blockage ratios on the explosion behavior of a propane–air premixed gas in a confined space is investigated. The maximum explosion pressure (P max), the deflagration index (K G), and the flame propagation process of the propane–air premixed gas with different barrier thicknesses are examined by using a horizontal closed tube with a length of 0.5 m and a diameter of 0.1 m and a high-speed camera. The atmospheric pressure and temperature of the premixed gas were 101.3 kPa and 18 °C, respectively. Based on the Canny operator, the position of the flame front at different times and the shape of the barriers before and after the explosion are determined, and the propagation speed of the premixed flame and the deformation rate of the barriers are obtained. The results indicate that the barriers change the flow field structure of the unburned gas and increase the folding degree of the flame front. With the increase in the blockage ratio, the explosion of a premixed system becomes more rapid and violent. Under the action of Rayleigh–Taylor instability, the variation in the flame propagation speed induces a change in the tube pressure. In addition, the deformation of a barrier causes a change in the maximum explosion pressure. The greater the deformation ratio of the barrier after the explosion, the larger the maximum explosion pressure.

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