Abstract The fuel composition highly affects formation of toxic pollutants in a diesel engine. The aromatics are found to be prominent fuel components that affect pollutant formation and at the same time help provide lubricity to moving engine parts. Therefore, their effect needs to be addressed systematically. This article elucidates aromatic types and its content effects on fuel atomization, regulated and unregulated emissions. Acoustic emission signals were also recorded for engine noise diagnosis during the exhaustive testing. Five different aromatics namely, ethylbenzene, α-methylstyrene, indene, tetralin and methylnaphthalene were blended in ratio of 15, 20 and 25% by mass with dearomatized hydrocarbon fuel and tested in a compression ignition engine. Results reveal that unregulated emissions, carbon monoxide (CO), unburnt hydrocarbon (HC) and particulate matter (PM) increase with aromatic content. However, nitrogen oxides (NOx) and acoustic emissions were found to be maximum with low aromatic content (15%). The polycyclic aromatics (indene, tetralin and methylnaphthalene) produce higher polyaromatic hydrocarbons (PAHs) and carbonyl emissions compared to monocyclic aromatics (ethylbenzene, α-methylstyrene). Additionally, polycyclic aromatics with 20% blending produced higher PAHs and carbonyl compound emissions than diesel with 23.6% aromatics. Ethylbenzene showed significantly better results for both spray and emission characteristics compared to the other tested aromatics.

中文翻译：

---

芳烃选择对更新配方燃料的适用性，以减少 CI 发动机的受管制和不受管制的排放

摘要 燃料成分对柴油发动机中有毒污染物的形成有很大影响。发现芳烃是重要的燃料成分，会影响污染物的形成，同时有助于为运动的发动机部件提供润滑。因此，需要系统地解决它们的影响。本文阐明了芳烃类型及其含量对燃料雾化、受管制和不受管制的排放的影响。在详尽的测试期间，还记录了声发射信号用于发动机噪声诊断。五种不同的芳烃，即乙苯、α-甲基苯乙烯、茚、四氢萘和甲基萘，以 15、20 和 25% 的质量比与脱芳烃燃料混合，并在压燃式发动机中进行测试。结果表明，不受管制的排放物、一氧化碳 (CO)、未燃烧的碳氢化合物 (HC) 和颗粒物 (PM) 随芳烃含量增加而增加。然而，发现氮氧化物 (NOx) 和声发射在芳烃含量低 (15%) 时最大。与单环芳烃（乙苯、α-甲基苯乙烯）相比，多环芳烃（茚、四氢化萘和甲基萘）产生更高的多环芳烃 (PAH) 和羰基排放。此外，与具有 23.6% 芳烃的柴油相比，混合 20% 的多环芳烃产生更高的 PAH 和羰基化合物排放。与其他测试的芳烃相比，乙苯在喷雾和排放特性方面表现出明显更好的结果。与单环芳烃（乙苯、α-甲基苯乙烯）相比，多环芳烃（茚、四氢化萘和甲基萘）产生更高的多环芳烃 (PAH) 和羰基排放。此外，与具有 23.6% 芳烃的柴油相比，混合 20% 的多环芳烃产生更高的 PAH 和羰基化合物排放。与其他测试的芳烃相比，乙苯在喷雾和排放特性方面表现出明显更好的结果。与单环芳烃（乙苯、α-甲基苯乙烯）相比，多环芳烃（茚、四氢化萘和甲基萘）产生更高的多环芳烃 (PAH) 和羰基排放。此外，与具有 23.6% 芳烃的柴油相比，混合 20% 的多环芳烃产生更高的 PAH 和羰基化合物排放。与其他测试的芳烃相比，乙苯在喷雾和排放特性方面表现出明显更好的结果。