This work explores pathways to achieve diesel-like, high-efficiency combustion with stoichiometric 3-way catalyst compatible combustion in a single-cylinder spark ignition (SI) research engine. A unique high stroke-to-bore engine design (1.5:1) with cooled exhaust gas recirculation (EGR) and high compression ratio (r_c) was used to improve engine efficiency by up to 30% compared with a production turbocharged gasoline direct injection spark ignition engine. Engine experiments were conducted with both 91 RON E10 gasoline and liquified petroleum gas (LPG) (i.e. autogas) and were compared to legacy gasoline data on the production engine. Geometric compression ratio (r_c) of 13.3:1 was used for both fuels with additional experiments at 16.8:1 for LPG only. Measurements of exhaust soot particle size and number concentrations were made with both fuels. Significant reduction in soot particles across the whole particle size range were achieved with LPG due to the elimination of in-cylinder liquid films. The effects of EGR, late intake valve closing (IVC) and fuel characteristics were investigated through their effects on efficiency, combustion stability and soot production. Results of 47% gross thermal efficiency, and 45% net thermal efficiency at stoichiometric engine operation, at up to 17 bar IMEP and 2000 r/min with 16.8:1 r_c were achieved with LPG. Estimated brake efficiency values were compared to a contemporary medium duty diesel engine illustrating the benefits of the chosen path for achieving diesel efficiency parity.

这项工作探索了在单缸火花点火（SI）研究发动机中通过化学计量的三元催化兼容燃烧实现类柴油高效燃烧的途径。与生产的涡轮增压汽油直喷相比，独特的高冲程到缸径发动机设计（1.5：1）具有冷却的废气再循环（EGR）和高压缩比（r _c），可将发动机效率提高多达30％。火花点火发动机。使用91 RON E10汽油和液化石油气（LPG）（即自动汽油）进行了发动机实验，并将其与生产发动机上的传统汽油数据进行了比较。几何压缩比（r _c两种燃料均使用13.3：1的）燃料，而液化石油气仅在16.8：1进行了附加实验。两种燃料均测量了烟灰的粒径和数量浓度。由于消除了缸内液膜，使用LPG可以在整个粒度范围内实现烟灰颗粒的显着减少。通过对EGR，进气门延迟关闭（IVC）和燃料特性的影响，效率，燃烧稳定性和碳烟产生的影响进行了研究。的47％的热效率总值，并在化学计量比发动机操作45％的净热效率，在高达17巴IMEP和2000转/分结果与16.8：1 - [R _Ç用液化石油气可以达到。将估算的制动效率值与现代中型柴油发动机进行了比较，说明了选择的途径可实现柴油效率平价的好处。