Effects of isopropanol ratio at different excess air ratios on combustion and emissions characteristics of an isopropanol/gasoline dual-fuel combined injection SI engine. (1st February 2023)

• Record Type: Journal Article
• Authors: Li, Decheng; Yu, Xiumin; Guo, Zezhou; Zhang, Jufang; Wang, Tianqi; Li, Yanwei
• Is Part Of: Fuel. Volume 333(2023)Part 2
• Publication Date: 2023-02-01
• Subjects: Pmax maximum value of the cylinder pressure curve -- APmax crank angle corresponding to Pmax -- ABE acetone-butanol-ethanol -- BTDC before top dead center -- BSFC brake specific fuel consumption -- CA crank angle -- CA 0–10 duration of crank angle from the spark timing to 10% of the energy of fuel released -- CA 10–90 duration of crank angle from 10% to 90% of the energy of fuel released -- CA 0–90 duration of crank angle from the spark timing to 90% of the energy of fuel released -- CO carbon monoxide -- CO2 carbon dioxide -- IMEP indicated mean effective pressure -- COVIMEP coefficient of IMEP variation -- cc milliliter -- CNPC China National Petroleum Corporation -- DI direct injection -- EDI ethanol direct injection -- GPI gasoline port injection -- GDIr gasoline direct injection ratio -- HC hydrocarbons -- HEDI hydrous ethanol direct injection -- IBE isopropanol-butanol-ethanol -- IDI isopropanol direct injection -- IPAr isopropanol ratio -- MBT minimum advance for best torque -- MPI methanol port injection -- NOx nitrogen oxides -- PN particle number -- PFI port fuel injection -- PM particulate matter -- PI port injection -- SI spark ignition -- λ excess air ratio; Isopropanol -- Combined injection -- Dual-fuel -- Combustion -- Gasoline -- Emissions; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2022.126507
• Languages: English
• ISSNs: 0016-2361

Abstract

Highlights: An injection mode of isopropanol direct injection plus gasoline port injection is proposed. Isopropanol can optimize combustion in the cylinder. Isopropanol can improve power performance and operation stability. Isopropanol can decrease unburned HC emissions, CO emissions and NOx emissions. Isopropanol hoists the ability of the engine operating under lean-burn conditions. Abstract: Energy crises and environmental issues require the development of green fuels for engines. Isopropanol is an excellent performance renewable alternative fuel for SI engines. It can be prepared by IBE fermentation. However, there have been few studies on the use of isopropanol/gasoline dual fuel in SI engines, especially based on the combined injection technology. For dual-fuel engines, the combined injection technology can further achieve clean combustion by flexibly controlling the fuel composition in the cylinder. Therefore, it is significant to combine the isopropanol/gasoline dual-fuel with the combined injection technology. The effects of the isopropanol ratio at different λ values on combustion and emissions characteristics of an isopropanol/gasoline dual-fuel combined injection SI engine were studied in this paper. The injection mode is isopropanol direct injection plus gasoline port injection. Six isopropanol ratios (0 %, 20 %, 40 %, 60 %, 80 %, 100 %) and five λ values (0.9, 1, 1.1, 1.2, 1.3) are set. The engine was tested at 1500 rpm with an intake pressure of 50 kPa. It is shown that isopropanol addition improves combustion, increases Pmax and maximum heat release rate, and shortens ignition delay period, rapid combustion period, and combustion duration. As the isopropanol ratio increases, the IMEP increases and the COVIMEP decreases. The improvements in combustion, IMEP and COVIMEP brought by the addition of isopropanol were more obvious under lean-burn conditions. Isopropanol addition effectively reduces unburned HC emissions, CO emissions, and NOx emissions. A higher isopropanol ratio in the mixture leads to better power and emissions performance. Isopropanol is a promising alternative fuel for engines, but its corrosive properties can damage the rubber parts of engines.