为了研究己烯酸甲酯在均质压燃条件下的着火规律，通过一台快速压缩机开展了3-己烯酸甲酯(mhx3d)在上止点压力为1.1，1.5，2.0MPa，当量比为0.5，1.0，1.5条件下的着火试验.并将mhx3d着火延迟与己酸甲酯(mhx)在上止点压力为1.5，2.0MPa，当量比为1时的实验结果进行了对比.使用CHEMKIN-PRO软件对mhx3d和mhx在较宽的温度范围内的着火延迟进行模拟，并进行了反应物浓度分析、敏感性分析和反应路径分析，研究了影响着火的重要基元反应.此外，在mhx3d中加入正丁醇(比例20%，40%，60%)来研究正丁醇对mhx3d着火延迟的影响.结果表明：mhx3d的当量比减少会增大着火延迟，减小最大燃烧压力；mhx3d的着火延迟随着正丁醇含量的增加而增大；mhx3d的着火延迟会随上止点压力的增大而减少；与mhx相比，mhx3d不存在明显的负温度系数现象，这是因为mhx3d中含有碳碳双键.试验测量了mhx3d的着火延迟，揭示了双键结构对mhx3d着火的影响.
In order to investigate the ignition characteristic of methyl trans-3-hexenoate under homogeneous charge compression ignition conditions, autoignition experiments of methyl trans-3-hexenoate were carried out through a rapid compression machine at compressed pressures of 1.1, 1.5 and 2.0 MPa with equivalence ratios of 0.5, 1.0 and 1.5. The ignition delay of methyl trans-3-hexenoate was compared with that of methyl hexanoate at compressed pressures of 1.5 and 2.0 MPa with equivalence ratio of 1.0. Besides, simulations were performed with CHEMKIN-PRO software. Sensitivity analysis and reaction pathway analysis were conducted to find out the important elementary reactions that control ignition. The effect of n-butanol on ignition delay was studied by adding n-butanol in methyl trans-3-hexenoate. It was found that as the equivalence ratio decreased, the maximum combustion pressure reduced and the ignition delay of methyl trans-3-hexanoate increased. The addition of n-butanol increased the ignition delay, and larger ignition delay was measured with higher content of n-butanol. It was also found that the ignition delay of methyl trans-3-hexenoate decreased with the increase of the compressed pressure. Compared with methyl hexanoate, methyl trans-3-hexenoate features only one stage ignition and no obvious negative temperature coefficient phenomenon. This was due to the existence of carbon-carbon double bond structure in methyl trans-3-hexenoate. This study measured the ignition delay of methyl trans-3-hexenoate and revealed the effect of carbon-carbon double bond on the autoignition characteristic of methyl trans-3-hexenoate.
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