Influence of hydrogen and oxygen on the initial steps of soot formation

碳纳米颗粒作为燃烧产生的污染物和重要的工业产品发挥着重要作用。因此，对它们的形成途径的理解和建模具有很高的兴趣。特别是，氢和氧在潜在的反应中起着重要的作用。然而，对机械细节的系统研究却很少。因此，分子和键合的氢的影响以及分子氧的影响以及添加剂对颗粒诱导时间，颗粒形成速率，颗粒体积分数，颗粒形态，以及对导致烟灰的反应通道的影响将在广泛的反应条件和建模下使用密切的实验相互作用进行研究。拟议的项目在专题和方法上系统地扩展了第一个项目期间开展的工作，并以第一个项目期间发展和展示的实验能力为基础。作为前体系统，乙烯，乙炔和苯（有和没有添加的含氧化合物甲醇，正丁醇和呋喃）将被研究为具有代表性的烃类与可变的C/H比under热解和温和的氧化条件。研究表明，含氧燃料和含氧燃料组分的混合物导致烟灰体积分数的减少和更小颗粒的产生的增加。在火焰条件下，分子和键合的氧可以通过增加自由基浓度和初始热释放或通过与热解条件相比的烟灰前体和烟灰颗粒的氧化反应来影响烟灰的形成。因此，烟尘的形成与无添加剂将研究byusing补充技术，如激波管（热解和氧化），燃烧气流反应器（热解）和麦肯纳燃烧器（氧化），涵盖了广泛的反应条件下的研究。通过这些综合方法，可以研究烟灰形成的所有阶段：激波管结合原位，在线和离线技术提供了明确的反应条件，其中气相组成和烟灰体积分数和颗粒尺寸可以用超高的时间分辨率确定。燃烧气体流和McKenna反应器能够在较长的反应时间内进行过程研究，并在烟灰形成的不同步骤中提供良好的取样可能性。所有的测量都将与理论研究和建模相关。该项目是基于德国和俄罗斯研究小组之间的密切合作。后者将向俄罗斯方面申请额外资金。

Carbon nanoparticles play an important role as combustion-generated pollutants as well as important industrial products. The understanding and modeling of their formation pathways, therefore, is of high interest. In particular, hydrogen and oxygen play an important role inthe underlying reactions. Systematic studies on the mechanistic details, however, are scarce. Therefore, the influence of molecular and bonded hydrogen as well as the influence of molecular Oxygen was as well as oxygenate additives on particle induction times, particle formation rates, particle volume fractions, particle morphology, as well as on reaction channels leading to soot will be studied using a close interaction of experiments under a wide range of reactionsconditions and modeling. The proposed project systematically extends thematically and methodically the work carried out in the first project period and builds on the experimental capabilities developed and demonstrated in the first period. As precursor systems, ethylene,acetylene, and benzene (with and without the addition of the oxygenates methanol, n-butanol and furans) will be studied as representative hydrocarbon classes with variable C/H ratios underpyrolytic and mildly oxidative conditions. Studies have shown that oxygenated fuels and the admixture of oxygenated fuel components leads to a reduction of the soot volume fraction and an increase in the production of smaller particles. At flame conditions, molecular andbonded oxygen can influence soot formation by increasing radical concentrations and initial heat release or by oxidation reactions of soot precursors and soot particles compared to pyrolysis conditions. Therefore, soot formation with and without additives will be studied byusing complementary techniques such as shock tubes (pyrolytic and oxidative), a burnt-gas flow reactor (pyrolytic) and a McKenna burner (oxidative) that cover studies under a wide range of reaction conditions. Through these combined approaches, all stages of soot formation can be investigated: shock tubes coupled with in situ, online, and offline techniques provide well-defined reaction conditions where the gas-phase composition and soot volume fractions andparticle sizes can be determined with ultra-high time resolution. The burnt-gas flow and McKenna reactors enable the investigation of processes on longer reaction times and provide good sampling possibilities throughout the different steps of the soot formation. Allmeasurements will be related to theoretical studies and modeling. This project is based on a close collaboration between a German and a Russian research group. The latter will apply for additional funding from the Russian side.