The impact of in-cylinder conditions on a turbocharged gasoline pre-chamber ignited engine

Turbulent Jet Ignition is a novel ignition technology that has demonstrated high thermal efficiency, especially at full loads, for lean burn IC engine applications. This technology has been extensively utilised in high speed motorsport engines such as Formula 1 and LMP1 where fuel flow rate is restricted thus driving motorsport engine manufacturers to improve fuel conversion efficiency making turbulent jet ignition technology very attractive for motorsport application. Thermal efficiency figures of over 50% have been claimed by certain Formula 1 engine manufacturers, however, the products of R&D are seldom publicised which make it difficult for novel technologies to enter the passenger car industry where improving fuel efficiency is critical to reduce global tailpipe emissions to protect the environment.
Over the years, numerous researchers have studied the turbulent jet ignition system however limited knowledge exists on the impact of in-cylinder conditions on the jet ignition system. This research focuses on studying the impact of in cylinder flow via port design, piston crown shapes and studying the impact of compression ratio and backpressure on a pre-chamber ignition system on a turbocharged lean burn high speed gasoline powered motorsport engine operated at full load conditions. Research findings include discovery of
positive impact of tumble flow on main-chamber combustion processes, a novel piston crown design which assists combustion processes via prechamber enrichment and enhancing main-chamber tumble flow. A positive impact of increasing compression ratio and the diminishing effect of increasing residual concentration on combustion have been discussed.

Advanced Engine Research Ltd supported and funded this research project.