Effect of point and mesh electrodes with applied negative voltage on premixed lean combustion

An experiment was conducted to investigate the different influences of the point electrode and the mesh electrode with applied voltages on the flame propagation and combustion characteristics of premixed CH₄/air mixtures at the excess air ratio of 1.6, room temperature, and atmospheric pressure. The results show that the flame shape deformed and the horizontal flame speed significantly increased when the voltage was applied to the two kinds of electrodes. Compared with those without the applied voltage, when the applied voltage was -5 kV, -10 kV and -12 kV, the vertical flame speed of the point electrode increased by 9.32%, 17.20% and 4.67% while that of the mesh electrode increased by 0.62%, -20.9% and -22.8%, respectively; the peak pressure of the point electrode rose by 6.4%, 9.8%, 11.2% while that of the mesh electrode rose by 5.6%, 2.4% and 1.3%, respectively. The two electrodes had slightly different effect on the flame at the input voltage of -5 kV while the point electrode was more beneficial to the flame propagation and combustion at the input voltages of -10 kV and -12 kV. It is likely that the point electrode performed better.