Experimental study of the combustion characteristics of methanol-gasoline blends pool fires in a full-scale tunnel

The combustion characteristics of methanol-gasoline blends pool fires were studied in a series of full-scale tunnel experiments conducted with different methanol and gasoline blends. The parameters were measured including the mass loss rate, the pool surface temperature, the fire plume centerline temperature, the ceiling temperature, the smoke layer temperature profile, the flame height, and the smoke layer interface height. The gasoline components were analyzed by GC-MS. The effects of azeotropism on the combustion characteristics of the different blends were discussed. On the basis of the results of the fire plume centerline temperature, the ceiling temperature, and the flame height, it shows that the tunnel fire regime gradually switches from fuel controlled to ventilation controlled with increasing gasoline fractions in the blends. The fire plume can be divided into 3 regions by the fire plume centerline temperature for the different blends. The N-percentage rule to determine the smoke layer interface height is found to be applicable for tunnel fires with different blends for N=26.