Effects of Water Injection Strategies on Oxy-Fuel Combustion Characteristics of a Dual-Injection Spark Ignition Engine

Currently, global warming has been a serious issue, which is closely related to anthropogenic emission of Greenhouse Gas (GHG) in the atmosphere, particularly Carbon Dioxide (CO2). To help achieve carbon neutrality by decreasing CO2 emissions, Oxy-Fuel Combustion (OFC) technology becoming hot topic recent years. However, few findings have reported about implementation OFC dual-injection Spark Ignition (SI) engines. This work numerically explores effects Water Injection (WI) strategies on characteristics practical engine, including GDI (only using GDI), P50-G50 (50% PFI and 50% GDI) PFI). The will build conceptual theoretical foundation for SI engines, as well exploring solution increase engine efficiency. results show that compared Conventional Air (CAC), there significant BSFC under OFC. delay (?F) significantly prolonged, spark timing obviously advanced. duration (?C) bit shorter than P50-G50. There small benefit low water-fuel mass ratio (Rwf). with further Rwf from 0.2 0.9, an increment 4.29%, 3.6% 3.77% GDI, PFI, respectively. As WI (tWI) postpones around ?30 °CA conditions ? 0.8, sharp decrease more 6 g/kWh, this decline evident injection strategy. variation maximum cylinder pressure (Pmax) combustion phasing less affected temperature (TWI) or tWI. just TWI 298 K 368 regardless Consequently, appropriate are beneficial but fuel economy limited.