Role of Excited Species in Plasma Enhanced Combustion

米勒本研究的目的是确定非平衡等离子体促进燃烧的基本机制。重点是研究非平衡等离子体的激发态及其在自燃和火焰稳定中的作用和能量效率。在一个精心控制的环境中，通过在电晕放电中产生活性物质，然后将它们注入燃料-空气混合物中，分别研究各种物质（原子、自由基、激发态分子）的影响。反应过程将通过现场气体取样和激光诊断来确定。最近的出版物已经证明了这些低温等离子体在促进碳氢化合物的点火和火焰传播方面的价值。一个有趣的观察是，自燃和火焰发生在温度和化学计量超出正常可燃性限制的燃料测试。然而，最近的建模工作表明，等离子体产生的自由基浓度的增加不足以产生这种效果。此外，现有的研究还不能区分离子种和激发态对燃烧的促进作用，而传统的碳氢化合物燃烧研究基本上忽略了激发态。找到真正的机理是有效点燃和稳定火焰的关键，不仅在自燃阈值以上，而且在自燃阈值以下。这项研究结合了德雷塞尔大学燃烧和燃料研究小组的低温，预点火专业知识和德雷塞尔大学A. J.德雷塞尔等离子体研究所的等离子体专业知识，加强了科学工作，并使学生参与到由此产生的多学科研究活动中。该项目还将利用和利用德雷塞尔大学现有的项目，以提高研究生和本科阶段少数族裔的参与度，如IGERT（综合研究生教育和研究培训）、通往博士学位的桥梁、GAANN（国家需要领域的研究生助学金）、GEM（少数族裔研究生教育）、AMP（少数族裔参与联盟）和三个REU现场项目。向少数族裔学生介绍燃烧、等离子体、能源效率和减排，将有助于他们在这些领域探索和发展自己的职业兴趣。

CBET-0755632 MillerThe goal of this research is to identify the fundamental mechanisms by which non-equilibrium plasmas promote combustion. The specific focus is on examining excited species from a non-equilibrium plasma and their roles and energy efficiency in autoignition and flame stabilization. Effects of various species (atoms, radicals, excited molecules) will be studied separately in a carefully controlled environment by generating the active species in a corona discharge and then injecting them into a fuel-air mixture. Reaction progress will be determined using in-situ gas sampling and laser diagnostics. Recent publications have demonstrated the value of these low-temperature plasmas in promoting ignition and flame propagation of hydrocarbons. One intriguing observation is that autoignition and flames have occurred for temperatures and stoichiometries that are outside the normal flammability limits for the fuels tested. However, recent modeling work suggests that the increased radical concentration produced by plasmas is insufficient to produce this effect. Furthermore, existing studies have not been able to discriminate between the effect of ionic species or excited species in promoting combustion, and excited species have essentially been ignored in traditional hydrocarbon combustion studies. Finding the true mechanism is the key to effective flame ignition and stabilization not only above but also below the autoignition threshold. This research combines the low-temperature, pre-ignition expertise of the Combustion and Fuels Research Group at Drexel University and the plasma expertise of the A. J. Drexel Plasma Institute at Drexel University, strengthening the work scientifically and engaging students in the resulting multidisciplinary research activity. The project will also leverage and take advantage of existing programs at Drexel University for enhancing minority participation at the graduate and undergraduate level, such as IGERT (Integrative Graduate Education and Research Traineeship), Bridges to the Doctorate, GAANN (Graduate Assistantships in the Areas of National Need), GEM (Graduate Education for Minorities), AMP (Alliance for Minority Participation), and three REU site programs. Introducing combustion, plasma, energy efficiency, and emissions reduction to under-represented minority students will help them to explore and develop their career interest in these fields.