Physical and chemical effects of phosphorus-containing compounds on laminar premixed flame

Phosphorus-containing compounds are the promising halon alternatives for flame inhibitions.However,some literatures suggested that the phosphorus-related inhibitors may behave as the unfavorable ones that will increase the burning velocity under lean-burn conditions,and this indeed posed potential threats to the fire prevention and fighting.To seek deeper insights into the reaction process,a numerical investigation was actualized to study the phosphorus-related effects on methane-air flames.By replacing a phosphorus-related inhibitor with the corresponding decomposed molecules,the detailed promoting and inhibiting effects of combustion were separated from the general chemical effect.A comparative study was carried out to identify the interaction between the two effects under different combustion conditions.It is observed that the promoting effect becomes the dominant factor during the reaction process when the equivalence ratio is smaller than 0.60.In this lean-burn condition,the exothermic reactions were faster than the others within the reaction chains due to the reduction of radical recombination in hydrocarbon oxidation.The results are believed to be useful for the further application and improvement of flame inhibitors.