Control of HCCI Combustion in Diesel Engines

It is recognised world-wide that HCCI (Homogeneous Charge Compression Ignition) combustion will be in the medium term future the main alternative to existing engine combustion technologies to improve vehicle emissions. This is due to its potential to generate extremely low levels of NOx (nitrous oxide) and PM (particulate matter) simultaneously, breaking the traditional NOx-PM trade-off for compression-ignition engines. Research into HCCI has so far been mainly directed toward an understanding of the combustion process and how combustion may be managed throughout the load range of the engine. During these investigations it has become apparent that the control of the combustion process is possible but is difficult and poses a number of practical challenges. The aim of this project is to provide some possible solution for combustion phase control on diesel-oriented HCCI combustion by predicting pre-ignition conditions in the cylinder under various variable valve timing control strategies. Possible control models will be established and tested on a direct-injection diesel test engine equipped with VVA/VVT (Variable Valve Actuation/Timing).