Measurement and Simulation of SI Engine Fire-Up on Hydrogen Fuel

Results are presented from a brief validation study on software which was written to simulate one-dimensional unsteady state transport of gaseous fuel mixtures through the intake manifold of a multi-cylinder, homogeneous charge spark ignition engine, and which also models in-cylinder thermodynamic and fluid flow processes, flame propagation, combustion and emissions formation. The focus of this paper is on the transport of pure hydrogen through the intake manifold of a 1.6 liter engine during the transition from steady state motoring to fired operation, at excess air ratios of 1.8 and 2.35. Indirect verification of hydrogen transport characteristics was determined by comparing measured and predicted IMEP's for different cylinders during the period immediately after hydrogen fuelling commenced. This work forms part of a larger project aimed at simulation of SI engine cold starting on hydrogen-rich gaseous fuel mixtures which may be produced by partial oxidation of gasoline in a reformer.