As a carbon-free fuel, ammonia is considered as an attractive alternative fuel for internal combustion engines. However, ammonia has the problems of high ignition temperature and NOx emissions while using in engines. Methanol as liquid fuel is easy to store and transport. Ammonia-methanol blended fuel is probably-one of the most appropriate methods to solve the problem. However, there are few studies of chemical mechanism for the combustion of ammonia/methanol dual fuel. Moreover, it is important to study ammonia-methanol combustion by chemical reaction path analysis. In this paper, a chemical reaction mechanism of ammonia-methanol blends with 60 species and 399 reactions was developed. This mechanism can accurately predict the laminar burning velocity (LBV) and ignition delay time (IDT) in a wide range of equivalent ratios (Φ) and methanol blends. By using this chemical reaction mechanism, the effects of methanol addition on ammonia combustion and emissions at different equivalent ratios were numerically studied. Results showed that the addition of methanol significantly improves the chemical reactivity of ammonia, and blending a small amount of methanol can greatly reduce the IDT. However, the accumulation of radical HO₂ caused by ammonia production enhances the fuel NOx path of NH₂ → H₂NO, which, together with high temperature and oxygen enrichment, leads to a NOx peak of 12500 ppm at equivalent ratio of 0.8. However, with the increase of equivalent ratio, NOx emission will decrease, which is only 2500 ppm at equivalent ratio of 1.4. Due to the existence of cross reaction of NH₂ + CH₃OH = NH₃ + CH₂OH and NH₂ + CH₃OH = NH₃ + CH₃O between ammonia and methanol, NH₂ is difficult to participate in the thermal DeNOx process in the premixed combustion process, resulting in high NOx emissions. In addition, it is also found that after equivalent ratio of 1.1, H will replace OH as the most important chain propagation carrier.

作为一种无碳燃料，氨被认为是一种有吸引力的内燃机替代燃料。然而，氨在发动机中使用时存在着火温度高和NOx排放的问题。甲醇作为液体燃料，易于储存和运输。氨-甲醇混合燃料可能是解决该问题最合适的方法之一。然而，关于氨/甲醇双燃料燃烧的化学机理的研究很少。此外，通过化学反应路径分析研究氨-甲醇燃烧具有重要意义。本文建立了60种399个反应的氨-甲醇混合物的化学反应机理。该机制可以在很宽的当量比范围内准确预测层流燃烧速度（LBV）和点火延迟时间（IDT）（Φ ) 和甲醇混合物。利用该化学反应机理，数值研究了不同当量比下甲醇添加对氨燃烧和排放的影响。结果表明，甲醇的加入显着提高了氨的化学反应活性，掺入少量甲醇可大大降低IDT。然而，氨生成引起的自由基HO _{2的积累增强了NH 2}  → H _{2的燃料NOx路径}NO，与高温和富氧一起，导致当量比为 0.8 时的 NOx 峰值为 12500 ppm。但是，随着当量比的增加，NOx排放量会降低，当量比为1.4时仅为2500 ppm。由于氨和甲醇之间存在NH ₂  +CH ₃ OH = NH ₃  + CH ₂ OH和NH ₂  + CH ₃ OH = NH ₃  + CH _{3 O的交叉反应，NH 2}预混燃烧过程中难以参与热力脱硝过程，导致NOx排放量高。此外还发现，当量比达到1.1后，H将取代OH成为最主要的链传播载体。