Influence on fluorocarbons flammability limits in the mixtures of H2-N2O and CH4-N2O

Deflagration Characteristics of N2-Diluted CH4-N2O Mixtures in the Course of the Incipient Stage of Flame Propagation

“…Powell et al [4][5][6] used a flat flame burner and numerical modeling to study the laminar burning velocities of hydrogen-, methane-, propaneand propylene-N 2 O mixtures diluted with N 2 , at near-atmospheric pressure. Shebeko et al [7][8][9] reported the flammability limits, minimum inert concentrations, peak explosion pressures, maximum rates of pressure rise and laminar burning velocities of hydrogen-, methane-, propane-and butane-N 2 O mixtures in the presence of N 2 , CO 2 and several halogen derivatives by experiments in closed vessels, at standard conditions. Mével et al [10] carried out experimental studies in a spherical bomb and kinetic modeling at ambient conditions to study the flame propagation in H 2 -N 2 O-Ar mixtures.…”

Nitrous Oxide: Oxidizer and Promoter of Hydrogen and Hydrocarbon Combustion

“…The ignition of fuel–N 2 O gaseous mixtures by local energy sources was studied under a great variety of experimental conditions. Most studies were carried at ambient initial conditions − ,,− and reported the lower and upper flammability limits of fuel–N 2 O deflagrations, using neat fuel–N 2 O mixtures or fuel–N 2 O diluted with air and/or different inert gases. Numerous experiments were conducted at pressures and/or temperatures different from ambient, ,,,,,− close to conditions of interest for plants operating flammable N 2 O gaseous mixtures or for storage facilities.…”

“…The inhibiting action of several halogenated organic derivatives was studied in respect to the flammability limits of H 2 and C 1 –C 4 alkanes with N 2 O. ,,, …”

“…The pressure rise after ignition (7% from the initial pressure for U.S. standards, 5% for European standards) is used as the flammability criterion. Many experiments were conducted, however, in nonstandard vessels, with the scope of reproducing the real conditions where explosions may occur: cylinders of various volumes, 0.9–100 L, ,,,− , or spheres of various volumes, 10–50 L. ,,− At the same time, the ignition sources were changed in time, to obtain always the widest flammability limits, under constant initial pressure and temperature.…”

“…The influence of halogen derivatives was examined only for mixtures of H 2 , CH 4 , C 3 H 8 , and i-C 4 H 10 with N 2 O, at ambient pressure. ,,, Shebeko et al reported the LEL decrease for C 3 H 8 –N 2 O and i-C 4 H 10 –N 2 O at the addition of 1–10% C 2 F 4 Br 2 , in spite of the fact that C 2 F 4 Br 2 is known to be a strong inhibitor for combustion of organic gases and vapors in air. A similar effect of fluorinated hydrocarbons (CHF 3 , C 2 HF 5 , C 4 F 10 ) on the LEL of H 2 –N 2 O was reported by Shebeko et al; for the same H 2 –N 2 O mixtures, as well as for CH 4 –N 2 O and H 2 –CH 4 –N 2 O, the UEL decreased substantially after addition of halogenated compounds.…”