Technical Paper
Assessing the Limits of Downsizing in Diesel Engines
2014-11-11
2014-32-0128
Direct injection compression ignited (CI) engines are today's most efficient engine technology, granting efficiencies exceeding 40% for their optimal operation point. In addition, a strong technological development has allowed the CI engine to overcome its traditional weak points: both its pollutant emissions and the gap in specific power regarding its competitor, i.e. the spark ignited (SI) engine, have been noticeably reduced. Particularly, the increase in specific power has led to the downsizing as an effective method to improve vehicle efficiency. Despite the reduction in total displacement, the cylinder displacement of current CI engines is still around 0.5 liters. For some applications (urban light duty vehicles, Range Extenders…) it may be interesting to reduce the engine displacement to address power targets around 20kW with high efficiencies.
