Development of Non-Road Spark Ignited H2-ICE with Port Fuel Injection for Fixed Speed Applications

The hydrogen internal combustion engine (H2-ICE) is an attractive solution for decarbonizing heavy duty equipment. The paper describes the development of a heavy-duty 6-cilinder spark ignited (SI) hydrogen internal combustion engine using port fuel injection (PFI) of hydrogen. The H2-ICE targets non-road application and STAGE V emission legislation. The paper presents a development methodology using results from experimental combustion research on a heavy-duty single-cylinder research engine combined with detailed numerical analysis. Single-cylinder experimental combustion research results are used to determine key engine design parameters, such as the compression ratio, together with base engine operating conditions. Here, focus is on extension of the low engine-out NOx load range. CFD simulations, considering PFI system configuration and injection strategy are used to optimize the in-cylinder charge mixture homogeneity. Results are used to define full engine hardware, such as piston compression ratio, single-stage turbocharger and port fuel injection equipment. Furthermore, the paper discusses measures, both on hardware (fuel path and airpath components) and control software (e.g. misfire detection) level, taken to optimize performance and safeguard operational safety. Key engine emission and power performance characteristics of the full scale engine are presented for steady state and dynamic engine operation. Here, both engine-out as well as tailpipe emissions, including commercially available aftertreatment technology, will be shown. These results demonstrate the low engine-out NOx potential over diesel-like load range with respect to current STAGE V as well as next generation emission legislation. Finally, the integration of the engine into a stationary power application will be presented, including additional safety measures.