Experimental study of the ignition of lean methane/air mixtures using inductive and NRPD ignition systems in the pre-chamber and turbulent jet ignition in the main chamber

• Novel pre-chamber test rig with dual schlieren setups. Nanosecond repetitively pulsed discharge and inductive ignition systems. Spark on the turbulent jet main chamber. Flame front propagation in affects probability Ignition of very lean conditions is possible by combining NRPD TJI. The optimization combustion process spark engines has led to novel strategies ignite low reactivity mixtures, such as application Repetitively Pulsed Discharge (NRPD) systems Turbulent Jet (TJI). In present experimental work, an optically accessible setup was used investigate occurrence early flame development subsequent chamber methane/air mixtures at density relevant engine application. Two setups coupled fast recording cameras allow visualization both different pulse patterns terms number repetition frequency applied pre-chamber. Conventional NRPD-assisted are compared for first time hot effect air fuel ratios assessed laminar conditions. Results show that while always advantageous when standard ignition, higher amount energy added increasing pulses only success conditions, thus showing increased not governing mechanism successful ignition. Irrespectively initial (laminar or turbulent) pre-chamber, it shown optimum velocity exists ensures chamber, suggesting mixing plays a major role combination techniques, TJI, allowed assessing reliable