ignition delay and flame stabilization of the nature gas under lean combustion conditions
an experiment was conducted to investigate the effects of low-frequency alternating electric fields on the flame shape
propagation speed
combustion pressure and other characteristic parameters of premixed methane/air mixtures in a constant volume combustion bomb at room temperature and under high initial pressure of 3 local atmospheric pressure. The results show that the flame is stretched in the horizontal
and the average flame propagation speed increases when low-frequency alternating electric field of 10-100 Hz is applied to the electrodes. With the decreasing frequency the flame stretch deformation degree and flame propagation speed increase firstly then decrease and reach the maximum near 15 Hz. The peak combustion pressure increases
and the peak pressure arrival time
the initial combustion period and the main combustion period are shortened under alternating electric fields. As the frequency decreases
the changes of peak combustion pressure and flame propagation speed tend identically
but the change of peak combustion pressure arrival time tends oppositely
however both the peak combustion pressure and the peak arrival time get their maximum values near of 15 Hz
and increase by 19.90% and -42.23% respectively compared with the case without electric field.
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