Formation of C2+ hydrocarbons in methane/oxygen diffusion flames with chlorine, chloromethane, or hydrogen chloride additives

1990 ◽  
Vol 29 (4) ◽  
pp. 539-544 ◽  
Author(s):  
Remi Le Bec ◽  
Paul Marie Marquaire ◽  
Guy Marie Come
Keyword(s):  
Hydrogen Chloride ◽  
Oxygen Diffusion ◽  
Diffusion Flames ◽  
C2 Hydrocarbons

Structure in methane-oxygen diffusion flames

1975 ◽  
Vol 15 (1) ◽  
pp. 625-636 ◽  
Author(s):  
A. Melvin ◽  
J.B. Moss
Keyword(s):  
Oxygen Diffusion ◽  
Diffusion Flames

Studies of chlorine trifluoride flames

1955 ◽  
Vol 232 (1188) ◽  
pp. 78-87 ◽  
Keyword(s):  
Carbon Monoxide ◽  
Reaction Zone ◽  
Chemical Equilibrium ◽  
Oxygen Diffusion ◽  
Diffusion Flames ◽  
Carbon Disulphide ◽  
Main Reaction ◽  
Carbon Formation ◽  
Rapid Diffusion ◽  
Diffusion Of Hydrogen

Diffusion flames are described in which the fuels, hydrogen, carbon monoxide, carbon disulphide, water, ammonia, hydrocarbons and organichalides are burnt with chlorine trifluoride. Chemical equilibrium is almost complete in the main reaction zone as in oxygen diffusion flames, but the chlorine trifluorido flames possess several unusual features. Carbon formation is very pronounced with hydrocarbon fuels. Radicals such as C 2 and CN have a large partial pressure in mixed hydrogen +hydrocarbon/chlorine trifluoride flames, and their presence in a high-tem perature region enhances the luminosity of the flames. It is suggested that the persistence of these radicals may be due to the very rapid diffusion of hydrogen into the main reaction zone which effectively prevents the penetration of fluorine to the fuel side of the flame. Chlorine trifluoride flames are briefly com pared with fluorine flames.

A numerical study of the effect of radial confinement on the characteristics of laminar co-flow methane–oxygen diffusion flames

2011 ◽  
Vol 225 (5) ◽  
pp. 1213-1228 ◽  
Author(s):  
K Bhadraiah ◽  
V Raghavan
Keyword(s):  
Numerical Model ◽  
Oxygen Diffusion ◽  
Diffusion Flames ◽  
Numerical Study ◽  
Air Entrainment ◽  
Maximum Temperature ◽  
Low Oxygen ◽  
Numerical Predictions ◽  
Effect Of Oxygen ◽  
Different Diameters

A numerical investigation of the characteristics of laminar co-flow methane–oxygen diffusion flames has been carried out. The temperature and nitric oxide (NO) distributions in unconfined and partly confined flames are studied in detail. Radial confinements of different diameters and with a length of 150 times the fuel jet diameter have been considered to allow atmospheric nitrogen entry only from the top. A numerical model with a 43-step chemical kinetics mechanism and an optically thin radiation sub-model is employed to carry out simulations. The numerical model has been validated using the experimental data available in the literature. The effect of oxygen flowrate on temperature distributions is studied thoroughly. Confined flame extents are compared with the corresponding unconfined flame extents with the help of OH contours. The effect of confinement diameter on temperature and NO distributions is analysed in detail. At low oxygen flowrates, the extents of confined flames are higher than those of an unconfined flame. At a higher oxygen flowrate, the extent of unconfined flame becomes higher. The confined flames are in general hotter than the unconfined flames. However, at the highest oxygen flowrate and for an intermediate confinement diameter, the flame has the lowest maximum temperature. The amount of NO produced in confined flames is higher than the unconfined flames, due to air entrainment from the top of the confining tube, which increases the residence time for nitrogen transport and its oxidation. At the highest oxygen flowrate considered, numerical predictions show that for a given confinement length, there is an optimum confinement diameter which results in a minimum net production of NO among all the flames.

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