Turbocharged Six-Cylinder Direct Injection Hydrogen Fueled Spark Ignition Engine Combustion and NOx Control Model

Abstract

Hydrogen fueled engines play an important role in carbon free emissions, and also replacing the expensive fuel cell system due to pure hydrogen production and high capacity batteries. But NOx emissions were increased with hydrogen combustion because of superior properties of hydrogen towards proper mixing of hydrogen with air. Further, NOx emissions were increased in turbocharged commercial heavy duty vehicles with high power output. In this study, a 13.5 L turbocharged six-cylinder spark ignition (SI) engine was modeled with sub-control systems and simulated using AMESim simulation tool towards proper control over combustion and NOx control. The fuel-air equivalence ratio (FAER), exhaust gas recirculation (EGR) %, indicated mean effective pressure (IMEP) and engine speed operating conditions were considered for the simulation study towards efficient combustion of hydrogen fuel and NOx emissions control. At 22 bar IMEP, the specific NOx emissions were increased with the increase of equivalence ratio from 0.45 to 0.5; and decreased with the increase of EGR% from 0 to 5; and the specific NOx emissions were decreased with the increase of engine speed from 1200 rpm to 1400 rpm. From the simulated results, it was concluded that the specific NOx emissions were low at 1400 rpm engine speed, EGR of 5% and equivalence ratio of 0.45.