温度和乙醇对麻风树油甲酯蒸发特性的影响  

Effect of Temperature and Ethanol on Evaporation Characteristics of Jatropha Oil Methyl Ester

作　　者：闫晨朝 姜根柱[1] 罗会利 王筱蓉[1] YAN Chenzhao;JIANG Genzhu;LUO Huili;WANG Xiaorong(School of Shipbuilding Mechanical Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,China)

机构地区：[1]江苏科技大学机械工程学院,江苏镇江212003

出　　处：《生物质化学工程》2024年第3期25-32,共8页Biomass Chemical Engineering

基　　金：江苏省研究生创新基金项目(SJCX22_1930)。

摘　　要：为了探究温度和乙醇对麻风树油甲酯(JME)液滴蒸发特性的影响,采用挂滴式实验方法,在973和1073 K的温度下,研究不同乙醇添加量(0%,10%,50%)的JME液滴(JME,JME-E10和JME-E50)的蒸发过程,分析了温度与乙醇含量对燃油单液滴蒸发归一化直径平方的影响。结果显示:973 K时的燃油液滴的蒸发特性与1073 K时的燃油液滴的蒸发特性有明显差异,蒸发特性曲线不能简单地分为瞬态加热阶段、波动蒸发阶段和平衡蒸发阶段这3个阶段。环境温度和乙醇添加量都会在一定程度上影响麻风树油甲酯生物油的蒸发。在高温条件下,液滴中含有的易挥发成分形成气泡使得液滴膨胀发生微爆,并且单液滴的环境温度越高,蒸发时间越短,这是因为在骤变之前液滴的膨胀速率大于蒸发速率。液滴内存在气泡,且不断变大,这是因为气泡因内部压力大于环境压力而向液滴表面移动,气泡达到最大时,发生微爆。在973和1073 K时,JME有一段时间处于平衡蒸发,符合D^(2)定律,而JME-E10和JME-E50则不同,其在蒸发阶段液滴直径波动很大且蒸发过程中还发生了聚合反应。液滴随着温度增加平均蒸发速率变大,JME-E50在1073 K时,蒸发速率最大。3种燃油在不同温度下蒸发,最终都有少许残渣,这是因为不饱和组分发生聚合反应生成了高分子聚合物。To investigate the effects of temperature and ethanol on the evaporation characteristics of jatropha oil methyl ester(JME)droplets,the evaporation process of JME droplets(JME,JME-E10 and JME-E50)with different amounts of ethanol(0%,10%and 50%)was studied at the temperatures of 973 and 1073 K by droplet experiment.The effects of temperature and ethanol content on the normalized square diameter of single fuel droplet evaporation were analyzed.The results showed that the evaporation characteristics of fuel droplets at 973 K were significantly different from those at 1073 K.The evaporation characteristic curve cannot be simply divided into three stages:transient heating stage,fluctuating evaporation stage and equilibrium evaporation stage.Both ambient temperature and ethanol concentration affected the evaporation of JME bio-oil to a certain extent.Under high temperature conditions,the volatile components contained in the droplet form bubbles,which caused the droplet expand and underwent micro-explosion.The higher ambient temperature of a single droplet,the shorter evaporation time.This was because the expansion rate of the droplet was greater than the evaporation rate before the sudden change,and there were bubbles in the droplet until the bubble became larger.As the pressure was greater than the ambient pressure,it moved to the surface of the droplet,and when the bubble reached the maximum,a micro-explosion occurred.At 973 and 1073 K,JME was in equilibrium evaporation for a period of time,which conformed to the D^(2) law,while JME-E10 and JME-E50 were different in that their droplet diameter fluctuated greatly during the evaporation stage.The evaporation process also occurred in polymerization reaction.The average evaporation rate of droplets increased with increasing temperature,and the evaporation rate of JME-E50 was the largest at 1073 K.The three fuels evaporated at different temperatures and eventually had a small residue owing to the polymerization of the unsaturated components to form high molecular polymers.

关 键 词：麻风树油甲酯 蒸发 乙醇 单液滴 

分 类 号：TQ35[化学工程] TK42[动力工程及工程热物理—动力机械及工程]