Inhibition/Promotion Effect of C₆F₁₂O Addition on Premixed Laminar RP-3/Air Flames

C₆F₁₂O (Novec 1230) is one of the most potential substitutes of Halon 1301. However, the study of inhibition/promotion effect of C₆F₁₂O addition on aviation kerosene is rarely reported, which greatly limits the development and application of C₆F₁₂O in oil fire accidents. In this study, numerical research was conducted to study the inhibition/promotion effect of C₆F₁₂O addition by a newly developed and optimized RP-3/C₆F₁₂O coupling skeletal mechanism. A novel methodology based on fictitious species was proposed and adopted to identify the physical dilution and thermal effects as well as the chemical radical and thermal interaction effects of C₆F₁₂O addition. It is observed that both inhibition and promotion effects can be exhibited because the chemical effect includes radical and thermal interactions at different equivalence ratios. In order to explore the kinetic reasons, the reaction path analyses were conducted. The results indicate that the HF formation reactions and the O₂ consumption fluorine-containing reactions, as well as the reactions of H₂O + F = OH + HF and C₃F₇ + O₂ = C₃F₇O + O, were the key inhibition and promotion reaction routes, respectively. Compared with methane, the lower H/C ratio of RP-3 makes it more suitable for the use of C₆F₁₂O to suppress combustion.