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Global trends in the development of spark ignition internal combustion engines lead to the adoption of solutions that reduce CO2 emissions and fuel consumption. Downsizing is a well-established path for this reduction, but it is necessary to use other technologies in order to achieve these ever more rigorous levels. A homogeneous torch ignition system is a viable alternative for reducing CO2 emissions with a combined reduction in specific fuel consumption and increased thermal efficiency. Thus a prototype adapted from an Otto engine with four cylinders is used for analysis. The performance and CO2 emission reference data were initially obtained with the baseline engine operating with a stoichiometric mixture. Then for the same conditions of BMEP, angular velocity and gradual lean of the mixture from the stoichiometry, the results of the adapted system are obtained.

It developed a design and construction methodology of a stratified charge torch ignition system for an Otto engine aiming fuel consumption and pollutant emission reduction. The torch ignition system is made of a combustion pre-chamber equipped with a direct fuel injector, an air injector and a spark plug. Fuel is directly injected in the pre-chamber aiming the formation of a lightly rich air fuel mixture. The combustion process starts in the pre-chamber and as the pressure rises, combustion jet flames are produced through interconnection nozzles into the main chamber. The high thermal energy of the jet flames reduces the combustion time, increases the combustion efficiency and allows the engine to efficiently burn lean air fuel mixture of several kinds of fuel in the main chamber, even those that are difficult to ignite. After the combustion takes place in the pre-chamber, air is also injected to help the exhaust process of the combustion products of the previous cycle.