Investigation of boost pressure and spark timing on combustion and NO emissions under lean mixture operation in hydrogen engines

Hydrogen may become a replacement for liquid fossil fuels, contributing to greenhouse gas emissions reductions by improving the thermal efficiency of boosted lean burn spark ignition engines. Single-zone engine combustion models are simple, but can yield useful results as step in design process developing alternative fuel systems. The single-zone thermodynamic model is advanced implementing laminar flame speed sub-model investigate combustion, an extended Zeldovich mechanism nitric oxide emissions, and incorporating Livengood-Wu integral knock characteristics. were validated using published experiments giving satisfactory predictions between simulation experiment timing variation, manifold air pressure, equivalence ratios. A detailed analysis strategies showed that increased with hence be controlled through optimizing excess ratio start combustion. Further techniques achieve high prevent hydrogen SI discussed.