Effects of electric fields with different electrodes on methane/air lean combustion flame

In view of lower combustion rate and severe cyclical variation under lean condition, an experiment was conducted to investigate different effects of electric fields with the point electrode, column electrode and mesh electrode on the flame shape, propagation distance, combustion rate and pressure in a constant volume combustion bomb. The results show that the flame deforms and is stretched in the horizontal direction as applying voltage to these electrodes; the electric field with the mesh electrode affects flame most obviously; the longer the period for flame in electric field, the rarer the mixture, the greater the effect of electric field on the flame. In the case of voltage of -10 kV and excess air ratio of 1.2, 1.4 and 1.6, flame propagating speed increases by 66.82%, 112.42% and 126.16%, respectively. Compared with the case without applied voltage, the maximum increasing rate of relative combustion pressure rises by 71.60%, 113.55% and 114.97%, respectively.