Mechanisms of NO_xProduction and Heat Loss in a Dual-Fuel Hydrogen Compression Ignition Engine

Decarbonisation of heavy-duty diesel engines using hydrogen fuel: a review of the potential impact on NOx emissions

“…53 The effect of engine load on NO x emissions has been investigated in multiple studies. [45][46][47][51][52][53] Most found that when hydrogen is added to diesel, NO x emissions tend to decrease at low loads and increase at high loads. However, different experimental conditions mean that the denition of what constitutes 'low' and 'high' load varies between studies, as well as the 53 Zhou et al also found that ignition delay varies with both hydrogen addition and load, affecting NO x through altering heat release characteristics.…”

“…43 However, the use of DI requires more modifications to the original diesel engine. 44 A recent CI engine simulation suggested that NO x formation only falls lower than a diesel-only case with a hydrogen energy share above 80%, 45 arising due to improved fuel mixing and the increase in ignition delay caused by hydrogen addition.…”