Real driving emissions evaluation for a heavy duty vehicle based on engine-in-the-loop methodology

Abstract

In this paper, the engine-in-the-loop (EIL) methodology was used to study real driving emissions of a heavy-duty vehicle on an engine test bed. The virtual vehicle was combined with the actual engine to establish an EIL test platform. The result of the vehicle speed followability shows that the difference between the EIL simulated vehicle speed and the actual vehicle speed is within ±2 km/h, indicating that the vehicle cycle can be well reproduced on the engine test bed by EIL method. The EIL method shows high coincidence of engine operating points. Compared with real driving, the CO2, NOx and PN of EIL is 3.6%, 72.3% and 40% lower for this vehicle, respectively. Analysis shows that equipment difference is the key influencing factor for PN test accuracy of EIL, while the control of exhaust temperature and intercooler temperature play important roles in NOx test accuracy of EIL.

Keywords

• heavy duty vehicle
• engine-in-the-loop (eil)
• real driving
• emission