Autoignition and burning of a water-oil emulsion with its injection into heated air. I. Ignition lag of diesel fuel DL

The effect of the degree of emulsifying diesel fuel DL with water on the ignition lag with its pulsed high-pressure injection into heated air was studied experimentally. It is shown that with relatively small cyclic feed emulsification prolongs ignition and with large cyclic feed, when ignition lag of water-free fuel increases markedly, it accelerates it. The mechanism of cavitation dispersion of the liquid jet during exit from the spray nozzle, determining the flow of the fuel-air mixture, is examined for explaining certain characteristics of the autoignition process. Emulsification of fuel to a considerable extent intensifies cavitation dispersion and thereby affects the course of mixing and, consequently, ignition.