Study on micro-explosion intensity characteristics of biodiesel, RP-3 and ethanol mixed droplets

A method to measure the volume of tiny droplets was designed, and 10 kinds of aviation fuel (RP-3), biodiesel and ethanol mixed droplets with the same volume and different proportions were prepared by using this method. Two kinds of experimental platforms (heating plate and tube furnace) for observing droplet micro-explosion were established. The expansion, ejection and micro-explosion characteristics of mixed droplets at high ambient temperature (480 °C) were studied by a heating plate experimental platform consisting of a combustion chamber composed of 7 heating plates, a controllable movable slide rail and other equipment. The BD10R20E70 and BD40R50E10 mixed droplets produced ejection and expansion phenomena in the experiment, other kinds of mixed droplets not only produced expansion and ejection, but also produced micro-explosion, but the intensity of these micro-explosion was different. Moreover, secondary micro-explosion of droplets was also observed in the heating experiment of BD40R10E50 droplet. The calculation equation of micro-explosion intensity was established and the micro-explosion intensity of 10 kinds of mixed droplets was calculated. Through the analysis of the micro-explosion intensity value, four different levels of micro-explosion intensity were distinguished. The micro-explosion characteristics of BD60R10E30 and BD60E40 mixed droplets were compared and analyzed by using a tubular furnace experimental platform. The reason for the difference in micro-explosion intensity between the two mixed droplets was analyzed, and the rationality of the division of micro-explosion strength was verified.