Experimental Study on Micro-Explosion and Evaporation Characteristics of Jatropha Oil Droplets
The evaporation and micro-explosion characteristics of jatropha oil droplets under high temperature envi-ronment(673,773,873,973 and 1 073 K)were carried out using high-speed backlit imaging technique.The droplet evaporation characteristics of three main components of jatropha oil were analyzed separately.The results show that the micro-explosion of jatropha oil droplets is caused by the pyrolysis of internal components,and the micro-explosion intensity increases with the increase of ambient temperature.At 673 K,the jatropha oil droplets undergo stable evaporation,which includes three stages of initial expansion,equilibrium evaporation and residue evaporation.At 773-1 073 K,the droplet undergoes micro-explosion,which includes four stages of initial expan-sion,equilibrium evaporation,micro-explosion evaporation and residual evaporation.When the ambient tempera-ture is higher than 873 K,the phenomenon of"vapor plume"and"vapor cloud"is observed for the first time,and the droplet evaporation rate significantly increases.