Characterization by laser diagnostics of the sooting propensity of biomass-derived fuels intended to be used as environmentally-friendly substitutes to fossil fuels

该计划旨在提高对不同生物质衍生燃料的烟尘行为的了解，以支持更清洁能源载体的发展。实际上，烟尘是燃烧过程中产生的主要污染物之一，也是人为气溶胶的主要贡献者之一。为了限制其生产，以满足实际和未来的法规，来源减少仍然是发动机制造商特别考虑的一个关键选择。然而，仍然需要彻底了解多环芳烃(PAHs)和碳烟形成的物理化学机制(特别是在生物燃料的情况下)，以改进用于设计燃烧装置的计算程序的预测特性。因此，本计划的目的是提供关于不同分子作为抑烟剂的能力的有洞察力的发现，以期确定石油衍生燃料的环境友好替代品中长期商业化所必需的燃料特性。为此，将实验室规模试验和发动机试验联系起来的本提案由以下三个主要目标组成： 1)开发包含所有已知影响碳烟产生的燃料分子结构效应的预测性碳烟倾向指标。为此，将测量各种生物燃料的燃料当量烟尘指数(FESI)(包括呋喃异构体和来自木材热解的生物油的一些成分)。获得的结果将通过结构基团加性方法进行处理，以提出一组原始的预测性烟尘倾向基团贡献因子。 2)开发适用于预测发动机微粒排放的颗粒物(PM)指标。基于对直喷式柴油机和火花点火发动机排气口的测量，将提出综合FeSI值的PM指数公式，以表示燃料分子结构和燃料性质(包括挥发性因素)在燃料/氧化剂混合物形成中的作用。 3)开发实现上述目标所需的适当计量工具。这一横向任务包括1/开发用于同时检测碳烟和多环芳烃的时间分辨激光诱导白炽光/荧光(LII/LIF)技术，2/通过实施先进的优化算法对LII信号建模以推断关于碳烟物理性质的信息做出贡献。 在该计划结束时，将提出创新的测量和建模工具，以探索需要解决的一些主要问题，以便开发更清洁的燃料和燃烧技术，使加拿大的能源生产、航空航天和汽车行业等受益。

This program aims at improving the understanding of the sooting behavior of different biomass-derived fuels to support the development of cleaner energy carriers. Actually, soot is one of the major pollutants generated in combustion processes and one of the main contributors to anthropogenic aerosols. To limit its production with the view to meet actual and future regulations, source reduction remains a key option particularly considered by engine manufacturers. A thorough understanding of the physicochemical mechanisms involved in the formation of polycyclic aromatic hydrocarbons (PAHs) and soot is still required however (especially in the case of biofuels) to improve the predictive character of the computational codes used to design combustion devices. The purpose of the present program is therefore to provide insightful findings regarding the ability of different molecules to act as soot suppressors with the view to identify the must-have fuel properties necessary for the mid- to long-term commercialization of environmentally-friendly substitutes to petroleum-derived fuels. To do so, the present proposal which associates laboratory scale experiments and engine tests is composed of 3 main objectives summarized as follows: 1) Developing predictive sooting propensity indicators incorporating all the fuel molecular structural effects known to influence soot production. To do so, the Fuel Equivalent Sooting Index (FESI) of various biofuels (including furan isomers and some components of bio-oils derived from wood pyrolysis) will be measured. Obtained results will then be processed by means of a structural group additivity approach to propose an original set of predictive sooting propensity group contribution factors. 2) Developing Particulate Matter (PM) indexes suitable to predict engine particulate emissions. Based on measurements performed at the exhaust of direct injection Diesel and spark ignition engines, PM index formulations will be proposed integrating FESI values to represent the fuel molecular structure and fuel properties (including volatility factors) playing a role in the fuel/oxidizer mixture formation. 3) Developing adapted metrological tools necessary to achieve the above-mentioned objectives. Such a transverse task includes 1/ the development of a time resolved laser-induced incandescence/fluorescence (LII/LIF) technique for the simultaneous detection of soot and PAHs and 2/ contributions in the modeling of LII signals to infer information on soot physical properties through the implementation of advanced optimization algorithms. At the end of this program, innovative measurement and modeling tools will be proposed to explore some of the major issues needing to be addressed in order to develop cleaner fuels and combustion technologies that will benefit the Canadian energy production, aerospace and automotive industries among others.