Hydrogen-Diesel Dual Fuel Combustion Characterization for an Internal Combustion Engine

• Author / Creator

  McNally, Jakub T

• Hydrogen as a fuel has the potential to reduce tailpipe carbon dioxide emissions of vehicles to near-zero, while also allowing for the generation of a hydrogen-based economy and lowering humanity's dependence upon oil. Hydrogen-diesel dual fuel combustion, where hydrogen and diesel are combusted together within a diesel engine, allows for application of hydrogen combustion technology with current technologies. Offsetting diesel consumption with hydrogen can significantly reduce CO2 emissions, and allow for cleaner emissions engines with current-day technology. However, the dual-fuel combustion process is more complex than standard compression ignition or spark ignition combustion. To understand diesel-hydrogen dual fuel combustion, testing of various operating points with varied operating parameters must be conducted. This thesis outlines the modification and hydrogen dual-fuel testing of a Cummins QSB 4.5 L engine. The engine was modified to have port hydrogen injection into Cylinder 1 with a custom controller software implementation. Cylinder pressure and engine-out emissions were measured while running both hydrogen-diesel and pure diesel. The engine was run with a load ranging between 4.5 bar IMEP and 12.5 bar IMEP, equivalent to approximately 70 percent of the engine's maximum load. Hydrogen was injected into the engine with a fuel energy fraction of up to 92 percent. For most tests, a dual-diesel injection strategy was used, with the pilot timing advance being changed to facilitate earlier hydrogen combustion timings. Intake manifold pressure was varied to approximate turbocharged operation. It was found that increasing hydrogen replacement caused greater engine-out NOx compared to pure diesel for almost all load cases, and hydrogen caused a greater fraction of NO2 in the exhaust stream. Engine-out CO2 was able to be reduced by up to 89 percent, and engine-out particulate was reduced up to 97 percent. At operating points with a sufficient hydrogen mixture fraction, the engine efficiency was equivalent or greater than that while running pure diesel. Low hydrogen replacement amounts resulted in no premixed flame propagation, limiting engine efficiency and increased unburnt hydrogen emissions at lower loads. High hydrogen replacement was observed to cause more rapid combustion along with higher cylinder pressures compared to pure diesel combustion, limiting the maximum hydrogen replacement.

• Subjects / Keywords

  • Hydrogen
  • Diesel
  • Engine
  • Dual
  • Fuel
  • CO2
  • H2
  • Carbon
  • Dioxide
  • Reduction
  • Combustion
  • Characterization
  • Port
  • Injection
  • Efficiency
  • NOx
  • Particulate
  • Emissions
  • Performance

• Graduation date

  Spring 2024

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-z8jn-7s67

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.