Guo Junjiang, Peng Weijun, Zhang Shijie, Lei Jiazhi, Jing Jiantong, Xiao Ruyi, Tang Shiyun
School of Chemical Engineering, Guizhou Institute of Technology, Guiyang 550003, PR China.
Guizhou Provincial Key Laboratory of Energy Chemistry, Guiyang 550003, PR China.
ACS Omega. 2020 Mar 5;5(10):4924-4936. doi: 10.1021/acsomega.9b03786. eCollection 2020 Mar 17.
To meet the increasing need for clean combustion, improve the combustion efficiency of fuels, and reduce the pollutants produced in the combustion process, it is necessary to systematically study the combustion of hydrocarbon fuels. An accurate and detailed chemical kinetic model is an important prerequisite for understanding the combustion performance of hydrocarbon fuels and studying complex chemical reaction networks. Therefore, based on ReaxGen, new detailed mechanisms for the low-temperature combustion of -nonane are proposed and verified in detail in this study. Meanwhile, some international mainstream combustion models such as the LLNL model and the JetSurf 2.0 model are compared with ours, showing that the proposed new mechanisms can better predict the ignition delay combustion characteristics of -nonane, and they also hold in a wide range of conditions. In addition, the numerical simulation results of the concentration curve calculated for the new mechanisms, especially Model v2, are in good agreement with the experimental data, and the mechanisms can reproduce the performance of the negative-temperature-coefficient behavior toward -nonane ignition. The numerical simulation results of the laminar flame propagation velocity varying with the equivalence ratio are also in good agreement with the available experimental data. Finally, the ignition delay sensitivity of -nonane is analyzed by the sensitivity analysis method; the key reactions affecting the ignition mechanism are investigated; and the reaction path analysis is conducted to better understand the models' predicted performance. In a word, the new mechanisms are helpful to understand the ignition properties of large hydrocarbon fuels for high-speed aircrafts.
为满足对清洁燃烧日益增长的需求，提高燃料的燃烧效率，并减少燃烧过程中产生的污染物，有必要系统地研究烃类燃料的燃烧。准确而详细的化学动力学模型是理解烃类燃料燃烧性能和研究复杂化学反应网络的重要前提。因此，基于ReaxGen，本研究提出了新的壬烷低温燃烧详细机理并进行了详细验证。同时，将我们的模型与一些国际主流燃烧模型如LLNL模型和JetSurf 2.0模型进行了比较，结果表明所提出的新机理能够更好地预测壬烷的着火延迟燃烧特性，并且在广泛的条件下都适用。此外，针对新机理尤其是v2模型计算得到的浓度曲线数值模拟结果与实验数据吻合良好，该机理能够再现壬烷着火的负温度系数行为性能。层流火焰传播速度随当量比变化的数值模拟结果也与现有实验数据吻合良好。最后，通过敏感性分析方法分析了壬烷的着火延迟敏感性；研究了影响着火机理的关键反应；并进行了反应路径分析以更好地理解模型预测性能。总之，新机理有助于理解大型烃类燃料对高速飞机的着火特性。
