Experimental and theoretical investigation of ethyl methyl carbonate/air flames: Laminar burning velocity and cellular instability at elevated pressures
Experimental and theoretical investigation of ethyl methyl carbonate/air flames: Laminar burning velocity and cellular instability at elevated pressures
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DOI：
10.1016/j.fuel.2023.128206
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发表时间：
2023
期刊：
影响因子：
7.4
通讯作者：
Lulu Yin;Wu Xu;Yong Hu;Yong Jiang
中科院分区：
文献类型：
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作者：
Lulu Yin;Wu Xu;Yong Hu;Yong Jiang
碳酸甲乙酯（EMC）由于其在实际应用中作为与常规油衍生的液体燃料的共混物以及作为用于锂离子电池电解质组合物中的溶剂两者所显示的优点而受到极大关注。因此，更好地了解EMC/空气预混火焰的燃烧特性是必要的，这还没有得到很好的探索。为了实现这一目标，EMC/空气混合物的层流火焰传播进行了研究，使用定容燃烧室在1，2，5和8大气压的初始压力，与未燃温度为423 K和当量比范围从0.7到1.5。最近由Takahashi等人建立的EMC的化学动力学机制（Combust. Flame 2022）被用于理论预测，其准确地再现了在1-5个大气压下测量的LBV;然而，其低估了在8个大气压下的贫火焰条件下的LBV。根据火焰不稳定性分析，压力的增加导致流体动力学不稳定性增加，球形预混火焰的临界半径减小。同时，EMC/空气的富燃火焰具有较小的临界Peclet数和更严重的热扩散不稳定性。
Ethyl methyl carbonate (EMC) gained great attention because of its advantages shown in practical applications both as a blend with conventional oil-derived liquid fuels, and as a solvent being used in Li-ion cell electrolyte compositions. Thus, a better knowledge of the combustion characteristics of EMC/air premixed flames is necessary, which has not yet been well-explored. Towards this goal, the laminar flame propagation of EMC/air mixture was investigated using a constant-volume combustion chamber at the initial pressures of 1, 2, 5 and 8 atm, with the unburned temperature of 423 K and the equivalence ratios ranging from 0.7 to 1.5. A recently established chemical kinetic mechanism of EMC by Takahashi et al. (Combust. Flame 2022) was adopted for the theoretical prediction, which accurately reproduced the measured LBVs at 1–5 atm; however, it underpredicted the LBVs for the lean flame condition at 8 atm. According to the flame instability analysis, the increase in pressure leads to the elevated hydrodynamic instability and the decreased critical radius of spherical premixed flame. Meanwhile, the rich flames of EMC/air had the smaller critical Peclet numbers and suffered the more severe thermal-diffusive instabilities.