Experimental Study on Combustion Characteristics and Emissions Reduction of Emulsified Fuels in Diesel Combustion Using a Rapid Compression Machine

Effects of water-emulsified fuel on diesel combustion and emission reduction process were investigated under various ambient temperatures, equivalence ratios and water addition ratios using a rapid compression machine and a total-gas sampling device. The results indicate that promoted diffusion combustion of emulsified fuels offers a shorter combustion duration and an increase in amount of heat release when compared with those of gas oil. NO_x concentration decreases with increasing the water content in emulsion fuels. This reduction is due to low NO formation rate and short duration of NO formation. Laser extinction measurement of the in-chamber KL factor shows that soot oxidation is promoted for emulsified fuels during the diffusion combustion stage.