A multi-mode hybrid architecture is considered in order to improve the efficiency in real driving conditions. Vehicle simulations were performed to evaluate the benefits of this multi-mode powertrain and to identify the parameters affecting CO2 emissions. Different scenarios were analysed and results show that PHEV architectures should reach 50 gCO2/km (WLTC) considering a C-class vehicle.
The impact of H2 as a combustion enhancer was demonstrated and 47% peak indicated efficiency was achieved at lambda = 2, while PN and NOx emissions are also decreased. The main hurdle to overcome regarding H2 supplementation remains the overall energy efficiency for on-board H2 production. Codes for 3D CFD were also adapted to H2 combustion, and can be used for various applications. “H2 supplementation” can be an alternative path to FCEVs and to dedicated hydrogen ICE.
A pre-chamber ignition system was designed to support the combustion in lean conditions. Extreme dilution (up to lambda = 3) was achieved with a stable combustion process. 47% maximal indicated efficiency at lambda = 2 is also demonstrated, combined with less than 30 ppm NOx at low load. Key players are now investigating these ignition systems for automotive and heavy-duty applications. Further developments are on-going in several research and applied projects. 3 patents have been granted on this topic
Smart insulation coatings were developed to reduce heat loss. Coatings performance were assessed based on numerical and experimental investigations. A limited impact of coating was observed when used with a spark-ignited engine. Latest results with the final EAGLE engine concept and the final coating configuration show, however, a positive effect on heat loss reduction.
In parallel, two exhaust insulation techniques were tested: coated exhaust parts, and fiber mat insulation, and one of them showed promising result to improve the efficiency of lean engines.
A NOx storage catalyst was designed to fit the requirements of ultra-lean burn gasoline engines. The performance of various materials were quantified with granules and mini catalysts. The full size scale NSC was finally delivered for the multicylinder engine testing phase.
A closed loop combustion control applied to H2 injection, and then to pre-chamber ignition and injection was developed. Based on multi-cylinder engine tests, this strategy proved to be efficient to lower pollutant emissions and increase efficiency.
The electrified dual stage turbocharging system was calibrated for the EAGLE multi-cylinder engine and it was shown that the overall exhaust aftertreatment performance was in line with the expectations.
Several paths have been identified for further exploitation, either for industrial developments, or for other H2020 projects.
Communication and dissemination was very strong during the project, and some additional publications are still planned for 2021.
