Road transport, and in particular car transport, are facing the challenge to reduce both CO2 and pollutant emissions. The automotive industry is asked to give its contribution to combat more effectively climate change, improve the air quality of European cities and health conditions of European citizens.
The aim of the SYNERGY project was to study innovative pathways to achieve a 20% reduction of CO2 emissions of a diesel engine for a M1/M2 class motor vehicle. As an example, this means a target of 100 g/km applied for a Renault Scenic vehicle, so to meet future emissions Euro 6/7 standards without NOx post-treatment systems.
This work, carried out in the framework of industrial research, was applied to a motor-propelled unit with a cylinder capacity of 1.5 litres suitable for a compact car or family vehicle "with very low CO2 emissions and pollutants" responding to customers' expectations.
Experimental works (motor tests for preferred channels, using advanced engine benchmarks representative of hybrid solutions) and simulations (for the most advanced engine solutions) were carried out in order to optimize the proposed system.
Better comprehension and strengthened innovation research regarding:
- the overcharging adapted to low flow rates, in order to significantly improve the CO2/NOx trade-off (one of the major criticality of diesel engines)
- the thermal exhaust (particularly in "cold operation" conditions)
- the combustion with a suitable system downs peeding/high overcharging
- the hybridization, depolluting-oriented (and low CO2 emissions)
The project allowed to achieve the following technical improvements, particularly:
- the development of an innovative air loop, with significant technological advances in overcharging and cooling of admitted gases.
- the hybridization of the diesel engine, resulting in energy recovery when the vehicle slows down.
- These two channels can be operated independently or simultaneously.