Analysis of evaporation characteristics for different fuel oil droplets in sub/transcritical state
1. School of Automotive and Traffic Engineering，Jiangsu University, Zhenjiang，Jiangsu 212013，China；2.School of Mechanical Engineering, Henan University of Engineering, Zhengzhou, Henan 451191，China
Abstract：The sub/transcritical state has great influence on the evaporation rules of different fuel droplets. By building a high-temperature constant-volume droplet evaporation measurement device, droplet life, droplet diameter, droplet evaporation rate and other parameters of C12H26, C14H30, diesel and biodiesel droplets in different critical states were measured. The results show that compared to the subcritical state with temperature of 573 K, when the four droplets are in the transcritical state with temperature of 973 K, the evaporation rates are increased by 1.25, 1.03, 0.71 and 0.51 mm2·s-1, respectively. The evaporation rate of single-component droplets is higher than that of multi-component droplets. The droplet lifetimes are greatly reduced by 86%, 89%, 93% and 89%, respectively. In the transcritical state, the expansion stage of biodiesel droplet evaporation is short, and the square of droplet diameter is decreased nonlinearly with time, which is not consistent with d2 law. C12H26, C14H30 and diesel droplets do not have expansion stage, and the square of droplet diameter is decreased linearly with time, which is conformed to d2 law.
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2022, Vol. 43 
