Abstract
Keywords Compression ignition engine, spark ignition engine, performance, fuel consumption, market share
Abstract - In Europe the share of Diesel engines in the passenger car market increased significantly over the past ten years. This trend is due to the excellent thermodynamic efficiency and the very high specific torque resulting in a fun-to-drive character.
The gasoline engine still leads the European market. It has lower complexity, low noise emissions and excellent exhaust emission capability. The gasoline engines comply with the most stringent emission legislations all over the world.
This paper outlines a possible future scenario for both types of engines.
The Diesel engine faces some challenges to improve the emissions of particulates and nitrogen oxides. Modern injection systems such as the common rail system with multiple injections allow for further improvements in emissions and efficiency.
The gasoline engine has a number of possibilities to add technologies for further improvements. First of all, as nearly all the Diesel engines are turbocharged today, to have a fair comparison, the charging of the gasoline engine needs to be regarded as the solution for enhancing the performance. Throttleless load control, charge dilution and direct injection offer opportunities to further improve the thermodynamic efficiency of the gasoline engine and to lower the gap between the two combustion types. The use of alternative fuels such as natural gas will significantly reduce the CO2 emissions.
Which type of engine is to dominate the future is influenced by the boundary conditions with regard to emission legislation, fuel cost and performance. From a technical point of view there will be a very rapid integration of technologies into both the Diesel and the gasoline engine.
The gasoline engine is leading in the race on market share. But the race is still on.