Effect of surface reactions on ignition delay of methanol/air mixture

14th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications

物理学;能源学

Huo, J.P.^1 ; Yang, H.L.^1 ; Jiang, L.Q.^1 ; Wang, X.H.^1 ; Zhao, D.Q.^1

Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, China^1

关键词: Homogeneous combustion;    Ignition delay time;    Ignition delays;    Inhibitory effect;    Inhibitory mechanism;    Initial temperatures;    Sticking coefficients;    Suppression effects;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/557/1/012080/pdf
DOI  :  10.1088/1742-6596/557/1/012080

来源: IOP

【 摘 要 】

A surface reaction kinetic model for the combustion of methanol/air mixture was developed in order to investigate the ignition inhibitory mechanism of wall on the premixed gas in a micro closed volume. In this model, except for H, O, OH and CH3radicals, the absorption of hydrogen peroxide and hydroperoxyl on the surface were also considered. By applying CHEMKIN-Pro software, the model was integrated into the calculation of homogeneous combustion process of gas mixture. Surface reactions were found resulting in the increase of ignition delay time. The sensitivity analysis showed that the loss of hydrogen peroxide on the wall was the main reason, due to the direct suppression effect on the generation and accumulation of OH in the radical pool. However, the loss of hydroperoxyl would take the place of hydrogen peroxide as the main inhibitory factor when the sticking coefficient became as large as the order of 10-3. In addition, the ignition delay time increased with sticking coefficient or surface-area-to-volume ratio. Enhancing the initial temperature of premixed gas was able to reduce the inhibitory effect of surface reactions.