Experimental and modeling study on effects of N2 and CO2 on ignition characteristics of methane/air mixture

Journal of Advanced Research

Wen Zeng¹  Hongan Ma¹  Yuntao Liang²  Erjiang Hu³ 

[1] School of Aerospace Engineering, Shenyang Aerospace University, Liaoning, Shenyang 110136, PR China;State Key Laboratory of Coal Mine Safety Technology, Shenyang Branch of China Coal Research Institute, Liaoning, Shenyang 110016, PR China;State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Shanxi, Xi’an 710049, PR China;

关键词: Gas explosion;    Ignition delay;    Chemical shock tube;    Simulation;    Sensitivity analysis;   

DOI  :  10.1016/j.jare.2014.01.003

来源: DOAJ

【 摘 要 】

The ignition delay times of methane/air mixture diluted by N2 and CO2 were experimentally measured in a chemical shock tube. The experiments were performed over the temperature range of 1300–2100 K, pressure range of 0.1–1.0 MPa, equivalence ratio range of 0.5–2.0 and for the dilution coefficients of 0%, 20% and 50%. The results suggest that a linear relationship exists between the reciprocal of temperature and the logarithm of the ignition delay times. Meanwhile, with ignition temperature and pressure increasing, the measured ignition delay times of methane/air mixture are decreasing. Furthermore, an increase in the dilution coefficient of N2 or CO2 results in increasing ignition delays and the inhibition effect of CO2 on methane/air mixture ignition is stronger than that of N2. Simulated ignition delays of methane/air mixture using three kinetic models were compared to the experimental data. Results show that GRI_3.0 mechanism gives the best prediction on ignition delays of methane/air mixture and it was selected to identify the effects of N2 and CO2 on ignition delays and the key elementary reactions in the ignition chemistry of methane/air mixture. Comparisons of the calculated ignition delays with the experimental data of methane/air mixture diluted by N2 and CO2 show excellent agreement, and sensitivity coefficients of chain branching reactions which promote mixture ignition decrease with increasing dilution coefficient of N2 or CO2.

【 授权许可】

Unknown