Exploring the performance limits of a stratified torch ignition engine using numerical simulation and detailed experimental approaches

Highlights: • The limits of gasohol torch ignition engine performance was investigated by numerical simulation. • 42% of HC emissions reduction was achieved with the new simulated TI-engine version. • An average decrease of 37.4% in the NOx emissions was achieved with the new TI-engine layout. • The combustion stability was extended to much leaner mixture with the new TI-engine design. - Abstract: In a torch ignition engine system, the combustion starts in a pre-combustion chamber, where the pressure increase pushes the combustion jet flames through calibrated nozzles to be precisely targeted into the main combustion chamber. This paper presents the layout of the prototype engine and the developed fuel injection system. It continues with a detailed description of the performance of the torch ignition engine running on a gasoline/ethanol blend for different mixture stratification levels as well as engine speeds and loads. Also detailed analyses of specific fuel consumption, thermal and combustion efficiency, specific emissions of CO₂ and the main combustion parameters are carried out. A numerical model based on thermodynamic and kinetic analyses has been established in order to explore the performance limit of a stratified torch ignition engine. The paper concludes presenting the main numerical results obtained in this work, which show a significant increase in the torch ignition engine performance as compared with the commercial baseline engine.