This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Contribution of Injection Pressure to Improve Efficiency and NOx Emissions
Published May 20, 2009 by Society of Automotive Engineers of Japan in Japan
Event: JSAE Spring Conference
Low NOx combustion concepts towards future emission legislation and high specific power goals towards downsizing concepts are challenging concerning low air excess burning capability. To enable efficient combustion process, air/fuel mixing energy has to be intensified achieving sufficient egr tolerance respectively meeting exhaust gas temperature limits of turbochargers. Biggest impact on mixing energy has injection pressure, supporting significantly combustion efficiency. Injection pressure increase above 2000 bar supports downsizing concepts via higher spray velocity and re-adaptation of injection duration. MD commercial vehicle engine investigation pointed out potential of advanced injection pressures until 3000 bar towards excellent egr tolerance for combined lowest engine-out NOx and favorable fuel consumption, if highest hydraulic efficiency of pressure generation is ensured. However efforts on engine itself, injection and air system side are considerable.