Effects of spark duration on minimum ignition energy for methane/air mixture

This work investigated the effects of spark duration on the minimum ignition energy of methane/air mixtures in the closed vessel. The main findings from these experiments (all with methane/air mixture with the volume fraction 8.5%) are: (a) for given methane/air mixture, the minimum ignition energy is not constant and it changes with the spark duration, (b) the minimum ignition energies decrease from 6.8 mJ to 0.4 mJ as the spark durations increase from 0.657 μs to 4.31 μs, (c) the explosion pressure reaches the highest value when the spark duration is 2.627 μs and the minimum ignition energy 1.3 mJ, (d) the explosion pressures change with the ignition energy value and spark duration, and (e) the explosion temperature reaches the highest value when the spark duration is 2.627 μs and the minimum ignition energy 1.3 mJ.