Laminar burning velocity predictions for C1 and C2 hydrofluorocarbon refrigerants with air

Due to their high global warming potentials, many existing working fluids are being phased out. Their replacements will often be slightly flammable, and the burning velocity of refrigerant-air mixtures is a metric for ranking their flammability. To allow estimates of the flammability of new blends of agents, predictive tools for the burning velocity are being developed and require a kinetic mechanism. A hydrofluorocarbon (HFC) mechanism was developed 20 years ago to describe hydrocarbon-air flames with added trace amounts of hydrofluorocarbon fire retardants. In the present work, the mechanism has been updated slightly to include new HFC compounds, new rate data. The modified mechanism is used to predict steady, planar, 1D, unstretched burning velocities for mixtures of air with one- and two-carbon saturated HFC compounds R41 (CH3F), R32 (CH2F2), R161 (C2F5H), R152 (CH2F-CH2F), R152a (CH3-CHF2), R143 (CH2F-CHF2), R143a (CH3-CF3), R134 (CHF2-CHF2), and R134a (CH2F-CF3), for which existing experimental data were available.