Applied Chemical Engineering (Transferred)

The call for greenhouse gas emission reduction as the result of global warming has been the main cause of the more rigorous emission legislation in the road transportation sector. In response to such requirements, car makers opt for the ‘down-sizing’ trend for engine displacement with the aim to increase brake thermal efficiency by increasing engine load (mean effective pressure). However, this leads to higher potential of engine knocking and elevated NOx emissions. This study investigates the effects of combustion phasing induced by water injection via the intake manifold of a naturally aspirated GDI engine at MBT ignition timing fuelled with E20. Water up to 30% of fuel mass is portinjected during high engine load and maximum NOx reduction of up to 82% could be achieved as the result of lower RoHR caused by vaporisation of water. Water injection prolonged the ignition delay and combustion duration (CA1090) without deterioration of combustion stability (%COV of IMEP). The optimisation of ignition timing based on MBT can improve CO emission compared to EGR systems. The proposed study demonstrates the possibility to achieve low nitrogen emissions without the need of precious metal-based catalysts.

internal combustion engine; gasoline direct injection engine; water-injection; combustion phasing; NOx emissions; alternative fuel; maximum brake torque (MBT)

1. Lindsey R, Dahlman LA. Climate change: Global temperature. Available online: https://www.climate.gov/news-features/understanding-climate/climate-change-global-temperature (accessed on 31 July 2023).

2. Xie R, Fang J, Liu C. The effects of transportation infrastructure on urban carbon emissions. Applied Energy 2017; 196: 199–207. doi: 10.1016/j.apenergy.2017.01.020

3. Kittelson DB. Engines and nanoparticles: A review. Journal of Aerosol Science 1998; 29(5–6): 575–588. doi: 10.1016/S0021-8502(97)10037-4

4. Amelang S, Wehrmann B. “Dieselgate”—A timeline of the car emissions fraud scandal in Germany. Clean Energy Wire 2020.

5. Pulkrabek WW. Engineering Fundamentals of the Internal Combustion Engine, 2th ed. New Jersey: Pearson Prentice-Hall; 2004.

6. Heywood JB. Internal Combustion Engine Fundamentals. New York: McGraw-Hill; 1988.

7. Jiang C, Xu H, Srivastava D, et al. Effect of fuel injector deposit on spray characteristics, gaseous emissions and particulate matter in a gasoline direct injection engine. Applied Energy 2017; 203: 390–402. doi: 10.1016/j.apenergy.2017.06.020

8. Hergueta C, Bogarra M, Tsolakis A, et al. Butanol-gasoline blend and exhaust gas recirculation, impact on GDI engine emissions. Fuel 2017; 208: 662–672. doi: 10.1016/j.fuel.2017.07.022

9. Wang C, Xu H, Herreros JM, et al. Fuel effect on particulate matter composition and soot oxidation in a Direct-Injection Spark Ignition (DISI) engine. Energy & Fuels 2014; 28(3): 2003–2012. doi: 10.1021/ef402234z

10. Williams M, Minjares R. A technical summary of Euro 6/VI vehicle emission standards. International Council on Clean Transportation (ICCT); 2016.

11. Mock P. CO2 Emission Standards for Passenger Cars and Light-Commercial Vehicles in the European Union. International Council on Clean Transportation (ICCT); 2019.

12. Shi Y, Cai Y, Fan R, et al. Characterization of soot inside a diesel particulate filter during a nonthermal plasma promoted regeneration step. Applied Thermal Engineering 2019; 150: 612–619. doi: 10.1016/j.applthermaleng.2019.01.015

13. Wang Y, Wei H, Zhou L, et al. Effect of Injection Strategy on the Combustion and Knock in a Downsized Gasoline Engine with Large Eddy Simulation. SAE Technical Paper; 2020.

14. Xia F, Griefnow P, Tidau F, et al. Electric torque assist and supercharging of a downsized gasoline engine in a 48V mild hybrid powertrain. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 2020; 235(5): 1245–1255. doi: 10.1177/0954407020968956

15. Stone R. Introduction to Internal Combustion Engines, 4th ed. Springer; 2012.

16. Wei H, Zhu T, Shu G, et al. Gasoline engine exhaust gas recirculation—A review. Applied Energy 2012; 99: 534–544. doi: 10.1016/j.apenergy.2012.05.011

17. Liu F, Pfeiffer J. Estimation algorithms for low pressure cooled EGR in spark-ignition engines. SAE International Journal of Engines 2015; 8(4): 1652–1659.

18. Asano I. Measurement Systems for Diesel Exhaust Gas and Future Trends. Available online: http://www-origin.horiba.com/uploads/media/RE03-03-012-600.pdf (accessed on 31 July 2023).

19. Pandey AK, Nandgaonkar M, Suresh S. Comparison and Evaluation of Engine Wear, Performance, NOx Reduction and Nano Particle Emission of Diesel, Karanja and Jatropha Oil Methyl Ester Biodiesel in a Military720 kW, heavy duty CIDI Engine Applying EGR with Turbo Charging. SAE Technical Paper; 2020.

20. Singh SK, Agarwal AK, Sharma M. Experimental investigations of heavy metal addition in lubricating oil and soot deposition in an EGR operated engine. Applied Thermal Engineering 2006; 26(2–3): 259–266. doi: 10.1016/j.applthermaleng.2005.05.004

21. Aldajah S, Ajayi OO, Fenske GR, Goldblatt IL. Effect of exhaust gas recirculation (EGR) contamination of diesel engine oil on wear. Wear 2007; 263(1–6): 93–98. doi: 10.1016/j.wear.2006.12.055

22. Zhuang Y, Sun Y, Huang Y, et al. Investigation of water injection benefits on downsized boosted direct injection spark ignition engine. Fuel 2020; 264: 116765. doi: 10.1016/j.fuel.2019.116765

23. Zhu S, Hu B, Akehurst S, et al. A review of water injection applied on the internal combustion engine. Energy Conversion and Management 2019; 184: 139–158. doi: 10.1016/j.enconman.2019.01.042

24. Wan J, Zhuang Y, Huang Y, et al. A review of water injection application on spark-ignition engines. Fuel Processing Technology 2021; 221: 106956. doi: 10.1016/j.fuproc.2021.106956

25. Golzari R, Zhao H, Hall J, et al. Impact of intake port injection of water on boosted downsized gasoline direct injection engine combustion, efficiency and emissions. International Journal of Engine Research 2019; 22(1): 295–315. doi: 10.1177/1468087419832791

26. Wang C, Zhang F, Wang E, et al. Experimental study on knock suppression of spark-ignition engine fuelled with kerosene via water injection. Applied Energy 2019; 242: 248–259. doi: 10.1016/j.apenergy.2019.03.123

27. De Simio L, Gambino M, Iannaccone S. Effect of ethanol content on thermal efficiency of a spark-ignition light-duty engine. ISRN Renewable Energy 2012; 2012. doi: 10.5402/2012/219703

28. Duan X, Zhang S, Liu Y, et al. Numerical investigation the effects of the twin-spark plugs coupled with EGR on the combustion process and emissions characteristics in a lean burn natural gas SI engine. Energy 2020; 206: 118181. doi: 10.1016/j.energy.2020.118181

29. Zhang J, Yu X, Guo Z, et al. Effect of exhaust gas recirculation and spark timing on combustion and emission performance of an oxygen-enriched gasoline engine. ACS Omega 2022; 7(46): 42208–42220. doi: 10.1021/acsomega.2c05034

30. Eriksson L. Spark Advance Modeling and Control [PhD thesis]. Linköping University; 1999.

31. Li A, Zheng Z, Peng T. Effect of water injection on the knock, combustion, and emissions of a direct injection gasoline engine. Fuel 2020; 268: 117376. doi: 10.1016/j.fuel.2020.117376

32. Kim J, Park H, Bae C, et al. Effects of water direct injection on the torque enhancement and fuel consumption reduction of a gasoline engine under high-load conditions. International Journal of Engine Research 2016; 17(7): 795–808. doi: 10.1177/1468087415613221

33. Cazzoli G, Falfari S, Bianchi GM, Forte C. Development of a chemical-kinetic database for the laminar flame speed under GDI and water injection engine conditions. Energy Procedia 2018; 148: 154–161. doi: 10.1016/j.egypro.2018.08.043

34. Mingrui W, Sa NT, Turkson RF, et al. Water injection for higher engine performance and lower emissions. Journal of the Energy Institute 2017; 90(2): 285–299. doi: 10.1016/j.joei.2015.12.003

35. Wang J, Duan X, Liu Y, et al. Numerical investigation of water injection quantity and water injection timing on the thermodynamics, combustion and emissions in a hydrogen enriched lean-burn natural gas SI engine. International Journal of Hydrogen Energy 2020; 45(35): 17935–17952. doi: 10.1016/j.ijhydene.2020.04.146

36. Easter J, Bohac SV. Three way catalyst-selective catalytic reduction aftertreatment system evaluation for a lean burn gasoline engine operating in homogenous charge compression ignition, spark-assisted compression ignition, and spark-ignited combustion modes. Journal of Engineering for Gas Turbines and Power 2018; 140(12). doi: 10.1115/1.4039424

37. Oh SH, Triplett T. Reaction pathways and mechanism for ammonia formation and removal over palladium-based three-way catalysts: Multiple roles of CO. Catalysis Today 2014; 231: 22–32. doi: 10.1016/j.cattod.2013.11.048

38. Anufriev IS. Review of water/steam addition in liquid-fuel combustion systems for NOx reduction: Waste-to-energy trends. Renewable and Sustainable Energy Reviews 2021; 138: 110665. doi: 10.1016/j.rser.2020.110665

39. Hoppe F, Thewes M, Seibel J, et al. Evaluation of the potential of water injection for gasoline engines. SAE International Journal of Engines 2017; 10(5): 2500–2512. doi: 10.4271/2017-24-0149

40. Xu P, Ji C, Wang S, et al. Effects of direct water injection on engine performance in engine fueled with hydrogen at varied excess air ratios and spark timing. Fuel 2020; 269: 117209. doi: 10.1016/j.fuel.2020.117209

41. d'Adamo A, Berni F, Breda S, et al. A Numerical Investigation on the Potentials of Water Injection as a Fuel Efficiency Enhancer in Highly Downsized GDI Engines. SAE Technical Paper; 2015.

42. Vacca A, Bargende M, Chiodi M, et al. Analysis of Water Injection Strategies to Exploit the Thermodynamic Effects of Water in Gasoline Engines by Means of a 3D-CFD Virtual Test Bench. SAE Technical Paper; 2015.