In recent years, more stringent requirements on performance, fuel economy and emissions have led to increasingly complicated engine configurations. This paper is a study into the potential benefits of an EGR MAP optimization for low fuel consumption and lower mass emission.
The narrower environmental restrictions are the current challenge that Diesel engine manufacturers are facing in the last years. The demand on cleaner emissions (both for NOx and soot), the fuel consumption reduction and the customer claim for improved engine performance are variables that should be matched to attend the legislation and market requirements. The search for these problems solution is a target that needs to be continuously reached, as the limits for emissions are year-by-year being updated and becoming more and more severe. Also, fossil fuel saving is a must for the future trends due to the reduction of its global reserves, the high cost associated with new fuel sources research and the greenhouse effect. Besides the external demands, the automotive industry is on a process to reduce costs and improve its efficacy. Time-to-market reduction, less validation tests and prototypes generation, smarter solutions and more robust design are only some of the achievements that are being sought. On this way, the use of numerical simulation is a powerful and significant tool. In order to reduce emission levels, some external engine features can be applied, such as EGR or after-treatment systems. The optimization of the piston bowl and injector design may also bring significant improvements on NOx and soot reduction. Piston bowl profile, injector nozzle diameter and angle, injector position on combustion chamber, and calibration variables (injection start, fuel mass, etc..) are some of the parameters that can be set for this purpose. The larger use of EGR system is a trend for the upcoming Diesel engines as it is...