Experimental study on microwave plasma discharge and combustion of premixed methane and air at atmospheric pressure

In this work, we carry out the experiments on an atmospheric-pressure premixed methane and air microwave plasma discharge combustion with to study morphology, spatial distribution of species, temperature characteristics for various power values methane-to-air equivalent ratios (<i>Φ</i>) at a series measurement positions. The experimental results show that ratio 0.4 corresponds limit value lean-combustion air. And <i>Φ</i> < 0.4, flame is mainly characterized by induced discharge, while, ≥ constricted into filaments radially, natural occurs in region low reduced electric strength high strength, which affect each other. variations emission intensity OH (A-X) band, NH band CN (B-X) measuring position are measured using optical spectrometry (OES). It found near afterglow far afterglow. vibrational rotational determined analyzing bands CN(B-X) both temperatures ratio, exhibiting very different varying tendencies cases respectively. Finally, reaction pathway mechanism discussed basis comparative analyses spectra CH<sub>4</sub> diffusion flame, nitrogen combustion.