环状分子结构含氧燃油的层流火焰在高压环境下的碳烟生成机理研究

Soot emitted from combustion (e.g. from internal combustion engines) is a major pollutant, and it has been categorized as a known carcinogen for humans and recognized to contribute to environment pollutions. In order to reduce the soot emission from practical combustion devices further, it is requisite to clarify the fundamental mechanism of soot formation in combustion processes. Consequently, the goal of this research is the exploration of the mechanisms of sooting tendency in laminar flames of lignin-based oxygenated fuels with cyclic molecular structures at elevated pressure. Two lignin-derived oxygenate fuels with two typical cyclic molecular structures, namely saturated cyclic and aromatic (unsaturated cyclic) will be examined on sooting tendency in laminar flames at elevated pressure, namely cyclohexaneethanol and 2-phenyl ethanol respectively. Considering the crucial impacts of aromatic structure on the formation of soot, an extended research of three lignin-derived aromatic oxygenates, including anisole, benzyl alcohol and 2-phenyl ethanol, will be presented, and the effect of the position of oxygen group to the aromatic ring on sooting tendency in laminar flames at elevated pressure will be investigated. The soot volume fraction in the laminar flames will be evaluated by Laser-Induced Incandescence (LII) calibrated by means of the Line Of Sight Attenuation (LOSA) technique. The relationship of the calibration factors for different pressures between LII intensities and soot volume fraction from LOSA will be established by an optimized on-line calibration system. The conclusions of this research will shed more insight into the mechanisms about sooting tendency of the oxygenate fuels with cyclic structures, which will be valuable references for the utilizations of these fuels in internal.combustion engines.

燃烧（如内燃机）排放的碳烟既是环境污染的主要来源，又是危害人类健康的致癌物质。因此，为了进一步降低燃烧的碳烟排放，研究燃烧过程中碳烟形成的机理是十分必要的。该研究的目标是探索基于木质素的环状分子结构的含氧燃油的层流火焰在高压环境下的碳烟生成机理。具体包括：环己基乙醇（含饱和环）和苯乙醇（含苯环）的层流火焰在高压环境下的碳烟生成的对比分析；三种含苯环的含氧燃油（苯甲醚、苯甲醇和苯乙醇）的层流火焰在高压环境下的碳烟生成的对比分析，以探索含氧分子团相对于苯环的不同位置对碳烟生成的影响。本研究将利用激光诱导炽光测得层流火焰的碳烟生成的强度，并使用消光法进行标定而获得碳烟的体积分数。该工作将设计和搭建基于上述两种测试手段的实时在线标定系统，并利用该系统来构建标定系数随环境压力变化的函数。该研究的结论将揭示环状分子结构含氧燃油的碳烟生成机理，为其在内燃机中的合理利用提供重要的参考。

本项目按照研究计划首先改造高压层流火焰燃烧器及其燃油供给系统，优化了高压下不同燃油火焰的稳定性，搭建并调试完成了LOSA和LII的实时在线标定的光路。然后，本项目以基于木质素的二代生物质燃油为对象，鉴于环状分子结构对碳烟生成的重要影响，对典型的含氧环状结构分子替代燃油的层流火焰碳烟生成机理开展了深入细致的研究，探明了燃油的分子结构以及层流火焰的环境对碳烟生成机理的影响，为实现生物质替代燃油清洁燃烧提供了基础数据和参考。.该项目目前共发表论文11篇，其中SCI期刊论文8篇，会议论文3篇，另有已投稿在审的SCI论文4篇。而且，共申请发明专利两项，均已进入实审，另授权实用新型专利两项。该项目培养的学生中，已毕业硕士研究生9人，在读硕士研究生2人和博士研究生1人。此外，该项目的研究过程中，研究团队成员还多次参与国际和国内各种学术会议和交流活动。