Fuel Stratification Using Twin-Tumble Intake Flows to Extend Lean Limit in Super-Lean Gasoline Combustion 2018-01-1664
To drastically improve thermal efficiency of a gasoline spark-ignited engine, super-lean burn is a promising solution. Although, studies of lean burn have been made by so many researchers, the realization is blocked by a cycle-to-cycle combustion variation. In this study, based on the causes of cycle-to-cycle variation clarified by the authors’ previous study, a unique method to reduce the cycle-to-cycle variation is proposed and evaluated. That is, a bulk quench at early expansion stroke could be reduced by making slight fuel stratification inside the cylinder using the twin-tumble of intake flows. As a result, the lean limit was extended with keeping low NOx and moderate THC emissions, leading to higher thermal efficiency.
Citation: Moriyoshi, Y., Kuboyama, T., Kaneko, M., Yamada, T. et al., "Fuel Stratification Using Twin-Tumble Intake Flows to Extend Lean Limit in Super-Lean Gasoline Combustion," SAE Technical Paper 2018-01-1664, 2018, https://doi.org/10.4271/2018-01-1664. Download Citation