On minimum energy of ignition of methane-air mixtures

The spark ignition of methane-air mixtures of various compositions with the help of a high-voltage source based on a piezoceramic step-up transformer with a high output resistance was studied. The experiments were performed at volumetric flow rates up to 20 cm/s and discharge gap widths up to 6 mm. The results were compared to the published data. Gaseous mixtures were demonstrated to be initiated at a decreased ignition energy. The ignition energy was found to be substantially lower when the initiation occurred in the corona discharge regime.