The influence of different fuels and injection methods of RCCI and DCI in hybrid ICE-Battery vehicle performance

Abstract

The incorporation of two recent technologies of using the dual-fuel reactivity controlled compression ignition (RCCI) combustion engine within the hybrid electric vehicle (HEV) is practiced to show how this combination can reduce the emission and enhance the thermal efficiency of the system. In particular, the heat transfers from the engine wall and the exhaust heat flow from the engine under different injection modes and fuels are of interest. The study in terms of thermal performance, fuel consumption, and battery state of charge (SOC) focuses mainly on the comparison between three cases of D100 (pure diesel) as the reference (baseline conventional direct pure diesel injection) case, D80H20 (80% diesel, 20% hydrogen) direct co-injection (DCI), and D80H20 RCCI (port + direct dual fuel injection). The NOx emission and engine power in the simulated drive cycle are investigated where the battery capacity and D50M50 (direct co-injection of 50% diesel with 50% methanol) are the additional cases. The findings indicate that the Battery SOC is preserved in better condition when the RCCI mode engine is coupled in the hybrid vehicle. The piston wall heat flux for D80H20 in DCI increases by 45.2% and for the RCCI increases by 60.5% compared to baseline diesel injection mode. It is also proved that the HEV releases considerably lower NOx compared to DCI and more NOx compared to D100 and D50M50.