Puff-Jet Ignition of Methane in an Internal Combustion Engine

Abstract

The puff-jet, a mechanically assisted ignition system, produces a turbulent ignition kernel that enhances the combustion of methane, a slow burning fuel. Detailed mapping of the puff-jet ignition system in a motored internal combustion engine has confirmed preliminary results. Compared with a spark gap ignition system, the puff-jet decreased both the ignition delay and the burn duration of methane charges in a motored single cylinder internal combustion engine and extended the lean misfire limit. Output power from the same engine run continuously on lean air-methane mixtures was increased using the puff-jet system because of the ameliorated combustion characteristics using that ignition system rather than a conventional igniter. Further, the output power from the engine running continuously with the puff-jet was almost the same as that achieved with a plasma jet igniter, without the concomitant high energy demand or electrode wear