Diversifying energy resources and reducing greenhouse gas
emissions are key priorities in the forthcoming years for the
automotive industry. Currently, among the different solutions,
sustainable biofuels are considered as one of the most attractive
answer to these issues.
This paper deals with the vehicle application of an innovative
diesel fuel formulation using Ethanol to tackle these future
challenges. The main goal is to better understand the impact of
using biofuel blends on engine behavior, reliability and pollutants
emissions. This alternative oxygenated fuel reduces dramatically
particulate matter (PM) emissions; this paves the way to improve
the NOx/PM/CO₂ trade-off. Another major interest is to avoid adding
a particulate filter in the exhaust line and to avoid modifying
powertrain and vehicle hardware and therefore to minimize the
overall cost to fulfill upcoming emission regulations.
After a first part devoted to a description of the fuel
properties, the paper focuses on some combustion analysis pointing
out the effects of the new formulation. Then the fuel/engine
compatibility and its optimization on a production turbocharged
diesel multi-cylinder engine with high pressure exhaust gas
recirculation are investigated. Owing to advanced calibration
methods such as design of experiments, new maps are provided to
fully take advantage of the ethanol/diesel blend properties and to
enhance the engine behavior. It leads to a simultaneous decrease of
nitrogen oxides and particulate matter emissions with a potential
CO₂ emissions reduction and combustion noise decrease. The main
drawbacks could be an increase of unburned hydrocarbons and carbon
monoxide emissions.
Furthermore, after having successfully validated the new
settings on the test bench, some vehicle results on a chassis
dynamometer are presented on the New European Driving Cycle (NEDC)
to illustrate the effectiveness of this innovative fuel formulation
and the calibration adaptation. Finally the recalibrated vehicle,
integrating only Euro 4-compliant technologies (not equipped with a
diesel particulate filter device), with this new fuel satisfies
potentially Euro 5 emissions standards without sacrificing
driveability and service life.
