Experimental study on the flammability limit parameters of premixed methanol-gasoline vapor-air mixtures

In this research, the fire and explosion risks of methanol-gasoline blended clean fuels are assessed in experimental studies of the flammability limit parameters of methanol-gasoline vapors at different methanol proportions (M0∼M100) and initial temperatures (313–393 K). The experimental results show that when the proportion of methanol in the methanol-gasoline mixture increases, both upper and lower flammability limits increase. When the initial temperature increases, the lower flammability limit of a methanol-gasoline blend decreases, and a higher methanol volume fraction in methanol-gasoline mixtures corresponds to a more obvious decrease in the lower flammability limit. When the temperature increases from 313 K to 393 K, the lower flammability limit of M75 drops by 11.86%. Under the condition of inert gas dilution, the limiting oxygen concentration gradually decreases with increasing proportion of methanol in methanol-gasoline mixtures. Additionally, the explosion triangle of methanol-gasoline vapor expands to the lower left corner, which increases the deflagration hazard of methanol-gasoline mixture under low oxygen content conditions. The results of this research will help researchers evaluate the fire and explosion risks of related processes and devices and establish a technical index for the application of blended methanol-gasoline clean fuels.