Numerical Investigation of the Chemical Effect and Inhibition Effect Improvement of C3H2F3Br (2-BTP) Using the Perfectly Stirred Reactor Model

The overall chemical rate and chemical effect of CF3Br, 2-BTP and 2-BTP/CO2 with hydrocarbon flames are calculated using the perfectly stirred reactor (PSR) model. The chemical effects of CF3Br with CH4/air flames always inhibit combustion. The chemical saturation concentration of CF3Br in stoichiometric and lean (Φ = 0.6) CH4/air flames at 298 K and 1 bar is roughly 2.5% and 0.8%, respectively. The overall chemical rate of 2-BTP with moist C3H8/air flames is always less than the uninhibited condition and fluctuates with sub-inerting agent additions. The net chemical effect variation of 2-BTP is more complicated than experimented and calculated flame speeds with 2-BTP added to lean hydrocarbon flames. There are negative chemical effects (chemical combustion effects) with certain sub-inerting 2-BTP concentrations (0.015 ≤ Xa ≤ 0.034), which result in the experimented unwanted combustion enhancement in lean moist C3H8/air flames. CO2 can obviously improve the inhibition effect of 2-BTP in lean moist C3H8/air flames, driving negative chemical effects (enhance combustion) into positive chemical effects (inhibit combustion) with lean moist C3H8/air flames. No enhanced combustion would occur with the blends (2-BTP/CO2) when CO2 addition is larger than 4% in Φ = 0.6 moist C3H8/air flames at 298 K and 1 bar.

[1]  Valeri I. Babushok,et al.  Combustion properties of halogenated fire suppressants , 2012 .

[2]  Bradley A. Williams,et al.  CF3Br and other suppressants: Differences in effects on flame structure , 2002 .

[3]  Gregory T. Linteris,et al.  Stirred reactor calculations to understand unwanted combustion enhancement by potential halon replacements , 2012 .

[4]  Phillip R. Westmoreland,et al.  Thermochemical and chemical kinetic data for fluorinated hydrocarbons , 1995 .

[5]  Valeri I. Babushok,et al.  A Chemical Kinetic Mechanism for 2-Bromo-3,3,3-trifluoropropene (2-BTP) Flame Inhibition , 2015 .

[6]  Bradley A. Williams,et al.  Intermediate species profiles in low-pressure methane/oxygen flames inhibited by 2-H heptafluoropropane: comparison of experimental data with kinetic modeling , 2000 .

[7]  Valeria Di Sarli,et al.  Stability and Emissions of a Lean Pre-Mixed Combustor with Rich Catalytic/Lean-burn Pilot , 2014 .

[8]  Gennaro Russo,et al.  Effect of diluents on rapid phase transition of water induced by combustion , 2012 .

[9]  Valeri I. Babushok,et al.  Hydrocarbon flame inhibition by C3H2F3Br (2-BTP) , 2015 .

[10]  Yong Jiang,et al.  Influence of halon replacements on laminar flame speeds and extinction limits of hydrocarbon flames , 2017 .

[11]  Yong Jiang,et al.  Numerical investigation of the chemical and physical effects of halogenated fire suppressants addition on methane–air mixtures , 2016 .

[12]  Fumiaki Takahashi,et al.  Understanding overpressure in the FAA aerosol can test by C3H2F3Br (2-BTP). , 2016, Combustion and flame.

[13]  Joseph A. Senecal,et al.  Determination of cup-burner extinguishing concentration using the perfectly stirred reactor model , 2008 .

[14]  V. Di Sarli.  Stability and Emissions of a Lean Pre-Mixed Combustor with Rich Catalytic/Lean-burn Pilot , 2014 .

[15]  Valeri I. Babushok,et al.  Chemical limits to flame inhibition , 1998 .

[16]  Hongsheng Guo,et al.  The chemical effect of CO2 replacement of N2 in air on the burning velocity of CH4 and H2 premixed flames , 2003 .

[17]  Gregory T. Linteris,et al.  Premixed flame inhibition by CF3Br and C3H2F3Br (2-BTP) , 2016 .

[18]  V. S. Babkin,et al.  On the mechanism of laminar flame propagation at high pressures , 1971 .

[19]  S. Kondo,et al.  Flammability assessment of CH2CFCF3: comparison with fluoroalkenes and fluoroalkanes. , 2009, Journal of Hazardous Materials.

[20]  Anthony P. Hamins,et al.  Inhibition effectiveness of halogenated compounds , 1998 .

[21]  P. Sunderland,et al.  Combustion inhibition and enhancement of premixed methane–air flames by halon replacements , 2015 .