Experimental study of boiling characteristics in a small emulsified diesel pool fire

The use of emulsified diesel fuel in internal combustion engines reduces fuel consumption and engine emissions. The water content is a key factor affecting the combustion efficiency of emulsified diesel fuels. The combustion and boiling characteristics of emulsified diesel fuel pool fires were studied here using a 150 mm diameter stainless steel tray to find ways to reduce casualties and property losses. The water contents of the emulsified diesel fuels were 0%, 5%, 10%, 15% and 20%. The combustion characteristics of the emulsified diesel fuel pool fires were divided into the initial growth stage, boiling combustion stage, pulsation stage, stable combustion stage and extinguishing stage based on the variations of the burning rate and the flame height. The combustion characteristics during the first three stages were affected by the water content while the combustion characteristics during the final two stages were similar to those of pure diesel fuel fires. Increasing the water content caused the durations of the boiling combustion stage and the pulsation stage to first become longer, then become stable and then become longer again while the duration of the stable combustion stage first decreased, then became stable and then decreased again with increasing water content. Boiling combustion occurs during emulsified diesel fuel pool fires which wakes the flame heights decrease. This study will help risk assessments of emulsified diesel fuel fires.