Effect of late inlet valve closing on NG-Diesel RCCI combustion in a heavy duty engine

Paper in proceedings, 2017

The reactivity controlled compression ignition (RCCI) concept has the potential to make combustion cleaner and more efficient. This paper describes studies on RCCI combustion using natural gas (NG) and diesel as high-octane and high-cetane fuels, respectively. The purpose of this study is to investigate the influence of late inlet valve closing on NG-diesel RCCI combustion. Experimental results reveal that indicated thermal efficiencies over 50% were achieved for most NG-diesel RCCI combustion cases at various inlet valve closing (IVC) timings. RCCI combustion also achieved ultra-low NOx and soot emissions, albeit at the cost of high UHC and CO emissions. Numerical work was also conducted to explore NG-diesel RCCI combustion details.