采用核磁共振信息的FACE汽油替代燃料机理构建

Surrogate Fuels Formulation for FACE Gasoline Using the NMR Spectroscopy

提出了一种基于核磁共振分析所得的官能基团信息来构建替代燃料模型的新方法。根据核磁共振的光谱信息,定义了五种基本官能基团:烷烃CH_3基团、烷烃CH_2基团、环烷烃CH-CH_2基团、烯烃CH-CH_2基团和芳香烃C-CH基团,并通过匹配实际燃料的这些官能基团来构建FACE汽油替代燃料。选取正丁烷、正庚烷、异辛烷、甲苯、2,5二甲基己烷、甲基环己烷和1-己烯作为备选基础燃料,根据FACE F、FACE G、FACE I和FACE J四种目标燃料的官能基团信息选取合适的替代燃料组分,进而构建相应的替代燃料模型。将所获得的替代燃料机理用于模拟不同初始条件下激波管内的燃料氧化燃烧,模拟结果与实验数据的对比表明,所构建的替代燃料机理能较好地预测FACE汽油在不同温度、压力和当量比条件下的着火特性。

An efficient surrogate fuel formulation methodology which directly uses the chemical structure information from nuclear magnetic resonance（NMR） spectroscopy analysis has been proposed. Five functional groups, paraffinic CH2, paraffinic CH3, aromatic C-CH, olefinic CH-CH2 and cycloparaffin CH2, have been selected to show the basic molecular structure of the FACE（fuels for the advanced combustion engines） fuels. A palette that contains seven candidate components：n-butane, n-heptane, iso-octane, toluene, 2,5-dimethylhexane, methylcyclohexane and 1-hexene has been chosen for FACE gasoline fuels, and the specific components for FACE F, FACE G, FACE I and FACE J fuels are chosen to construct the mechanism of surrogate fuel according to their function group information. Whereafter, the accuracy of FACE surrogate models was demonstrated by comparing the model predictions against experimental data in homogeneous ignition under several initial conditions with different temperatures, pressures and equivalent ratios.