Common rail diesel systems featuring high-pressure direct-injection are the key to success in developing low consumption, high performance engines according to Bosch. Modern common rail direct injection diesel engines use up to 30% less fuel while emitting up to 25% less carbon dioxide (CO2) than comparable gasoline engines with manifold injection.
Bosch is working on developing both piezo and solenoid valve injectors further, extending the 10-year success story of the common-rail system. The new, highly dynamic solenoid valve injectors are similar to piezo injectors in terms of performance and are designed for injection pressures of more than 2,000 bar. As well as working towards increasing injection pressures, Bosch believes that emissions and fuel consumption could be further improved by increasing the pressure of the common rail pump.
Bosch is to introduce the CP4 common rail pump, with a pressure potential of 2,000 bar later this year. This is designed for the highest hydraulic efficiency and supports combustion processes with extremely high injection pressures even at low engine speeds and medium to high loads. The ability to vary the injection timing has a significant effect on engine performance - pre-injection reduces NOx emissions and noise, while post injection reduces soot emissions.
