Experimental study is performed on the production of the bio-diesel emulsion fuel.In this research,a bubble pulse caused by an underwater explosion is used to emulsify samples,i.e.,water(in the range of 5–20%)and bio-diesel fuel with two-different specific surfactants.This mechanism of the emulsification is observed by a high speed video camera and calorimeter(SHIMADZU CA-4AJ)and Zetasizer Nano ZS(Malvern Co.)are employed to measure heat value and particle size of the emulsion fuel produced here,respectively.It is found that(i)the process of generating emulsification under the underwater explosion is disclosed,(ii)the stable emulsion fuel and water particle size in it are affected by HLB,i.e.,the ratio of two-different specific surfactants and the timewise stability of the emulsion fuel is attributed to the scattering intensity of the measured water particle size(Fig.1).