The combustion features of water-in-diesel fuel emulsions were studied in a single drop combustion chamber by means of high speed shadowgraphs, suspending emulsion drops to a thermocouple in order to follow their thermal history. Several emulsions were prepared by varying the internal parameters that affect their stability, such as water volume fraction, water particle size distribution and the amount of surfactant. It was found that the emulsion internal parameter which have influence on emulsion stability (water volume fraction and size distribution, quantity of surfactant) also influence the tendency towards micro-explosion. (C) 2013 Elsevier Ltd. All rights reserved.