多组分重油单液滴着火与燃烧特性  

Single droplet ignition and combustion characteristics of multi-component heavy oil

作　　者：陈健[1] 张扬[1] 张海[1] CHEN Jian;ZHANG Yang;ZHANG Hai(Key Laboratory for Thermal Science and Power Engineering of Ministry of Education,Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学能源与动力工程系,热科学与动力工程教育部重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2023年第4期603-611,共9页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金项目(52176116)。

摘　　要：该文研究了3种多组分重油单液滴在高温环境下的着火、微爆和燃尽特性。通过管式炉实验,记录了单液滴重油在着火和燃烧过程中的特征时间和特征直径的变化规律。实验发现重油的着火延迟时间和燃尽时间与组分、温度、初始直径密切相关。由于重油液滴的组分复杂且沸点不同,因此在燃烧过程中发生的膨胀对其燃烧特性有重要影响。热重质谱(thermogravimetric-mass spectrometry,TG-MS)分析的结果可以较好地解释膨胀的频率和幅度。实验结果表明:3种样品的膨胀次数与TG-MS结果中热解峰的数量一致,膨胀幅度与热解峰的高度呈正相关;多组分重油燃烧过程发生了明显的微爆现象。该文定义了液滴燃烧过程中的微爆强度,并发现其与重质组分占比、液滴初始直径和温度呈正相关关系。[Objective]Heavy oil is one of the heavy end products of the petroleum refining process and has high energy density,low price,and poor ignition and combustion performance.There is an increasing demand for heavy oil and substantial variation in the composition of heavy oil provided by different suppliers.Understanding the combustion characteristics of heavy oil,especially those related to ignition and burnout,is critical to safely use and effectively tune and control the combustion of heavy oil.The development of heavy oil burners can yield significant insights into this endeavor.The combustion of heavy oil in the furnace is essentially the combustion of a large number of liquid droplets.The study of the ignition and b[KG-*4]urnout characteristics of a single liquid droplet can lead to a better understanding of the combustion of heavy oil.[Methods]The composition of multi-component heavy oil is analyzed,and the single drop experiment is carried out.Considering the need to measure the temperature at the droplet center and take pictures of the static droplet during the experiment,the hanging drop method is chosen for studying single droplets of three multi-component heavy oils at different temperatures.Also,experiments are performed in tubular furnaces with different initial diameters to understand the correlation between the ignition and combustion characteristics of a heavy oil droplet and its composition,ambient temperature,and initial diameter.The droplet ignition delay is defined as the duration between the entrance of the droplet into the tubular furnace and its ignition.All experiments are conducted under visible light to enable observation of the variation in the ignition delay of liquid droplets and the time taken for the burn-out of their volatile components.Then the experiment is repeated under a strong backlight to better observe the change in the droplet radius during combustion.The obtained images are binarized by the MATLAB program,and the 256 brightness levels of the original image are converted into

关 键 词：燃料与燃烧 重油 液滴燃烧 微爆 

分 类 号：TK16[动力工程及工程热物理—热能工程]