Effects of Electric Fields on the Combustion Characteristics of Lean Burn Methane-Air Mixtures

Energies

Jianfeng Fang¹  Xiaomin Wu¹  Hao Duan¹  Chao Li¹  Zhongquan Gao¹ 

[1] Institute of Internal Combustion Engine, Xi’an Jiaotong University, Xi’an 710049, China; E-Mails:

关键词: electric field;    flame propagation speed;    electrically induced stretch;    lean burn mixture;    combustion pressure;    heat release rate;   

DOI  :  10.3390/en8042587

来源: mdpi

【 摘 要 】

In this work, the effects of the electric fields on the flame propagation and combustion characteristics of lean premixed methane–air mixtures were experimentally investigated in a constant volume chamber. Results show that the flame front is remarkably stretched by the applied electric field, the stretched flame propagation velocity and the average flame propagation velocity are all accelerated significantly as the input voltage increases. This indicates that the applied electric field can augment the stretch in flame, and the result is more obvious for leaner mixture. According to the analyses of the combustion pressure variation and the heat release rate, the peak combustion pressure P_max increases and its appearance time t_p is advanced with the increase of the input voltage. For the mixture of λ = 1.6 at the input voltage of −12 kV, P_max increases by almost 12.3%, and t_p is advanced by almost 31.4%, compared to the case of without electric fields. In addition, the normalized mass burning rate and the accumulated mass fraction burned are all enhanced substantially, and the flame development duration and the rapid burning duration are remarkably reduced with the increase of the input voltage, and again, the influence of electric field is more profound for leaner mixtures. The results can be explained by the electric field-induced stretch effects on lean burn methane-air mixture.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.