Advanced Diesel Technology to Achieve Tier 2 Bin 5 Emissions Compliance in US Light-Duty Diesel Applications

Future growth of the US light-duty diesel market is highly dependent on achieving cost effective and robust emissions solutions. For this reason, ACTION (Advanced Combustion Technology to Improve engine-Out NOx) is being developed by Ricardo. This research is delivering reduced emissions through the application of Highly Premixed Cool Combustion (HPCC). NOx reduction is primarily achieved through the reduction of charge oxygen concentration, accomplished by reducing air/fuel ratio and increasing exhaust gas recirculation. This approach coupled with enhanced combustion system efficiency delivers a practical approach to meet future emissions compliance while minimizing aftertreatment requirement.

The paper will examine key engine technology developments to deliver US Tier 2 Bin 5 emissions in Light Duty Diesel applications. In particular, Bin 5 emissions compliance will be possible in passenger car applications. ACTION level 2 technology will be sufficiently mature for 2007 and will require NOx aftertreatment solutions with 60-80% conversion capability. The paper describes progress to further apply the HPCC approach and lower engine-out NOx emissions while controlling fuel consumption and soot. The results show the potential to minimise the requirement for NOx aftertreatment. The paper describes key areas of development being undertaken by Ricardo research projects. In particular the importance of advanced air/EGR technology and combustion control is described.