An experimental investigation of an inertization effectiveness of fluorinated hydrocarbons in relation to premixed H2–N2O and CH4–N2O flames

• Flammability limits and some parameters of explosion were determined.
• The fluorinated hydrocarbons can reveal both inhibitive and promotive action on the flames.
• A qualitative explanation of the results obtained was done.
• Mixtures of flammable gas-nitrous oxide-fluorinated hydrocarbons were investigated.

An experimental investigation of an influence of trifluoromethane CHF3, pentafluoroethane C2HF5 and perfluorobutane C4F10 on near-limit hydrogen-nitrous oxide and methane-nitrous oxide premixed flames was performed. Flammability limits, a maximum explosion pressure ΔPmax, maximum rate of pressure rise (dP/dt)max, and a laminar burning velocity Su were determined. The flammability area in the case of N2O as an oxidizer is substantially wider than for the case of the oxidizer which is the mixture of oxygen and nitrogen with the O2 content 25% (vol.). The dependences of Su, ΔPmax and (dP/dt)max on concentration of the fluorinated hydrocarbons are characterizing by an availability of maxima which positions are close to the peak concentrations of the flammability regions. A qualitative interpretation of the results obtained is given.