Abstract
Keywords: alternative combustion, two stage supercharging system, double injection strategy
The rapidly increasing demand and consumption of fossil fuels result in discussions about the energy availability in the future. Each combustion process with crude oil based fuels emits CO2 well known as a greenhouse gas. Due to the rising carbon dioxide content in the air, the ACEA agreement (European Automobile Manufacturers Association) limits fleet average carbon dioxide to 140 g/km in the NEDC test cycle from 2008 (voluntary accepted by automotive industry). This target forces the European automotive industry to build highly efficient combustion engines that have to fulfil the demanding exhaust gas legislation of the EU.
Due to this requirements the state-supported competence network `KNET -Internal Combustion Engine of the Future´ was founded in 2003 to develop alternative diesel combustion processes with very low engine out emissions. KNET cooperation consists of three industrial partners namely AVL List GmbH, MIBA AG, OMV AG and one scientific partner, Graz University of Technology. The ambitious aim of the project is the development of a competitive passenger car diesel engine that fulfils oncoming legislations without any nitrogen oxide (NOx) exhaust-gas aftertreatment system. Present multi-cylinder engines with standard turbo charging systems (TC) do not have the required abilities to cover the complete NEDC load area in premixed combustion modes. Base for an extension of the alternative load area is an advanced TC system that is capable to deliver higher EGR rates and boost pressures than standard systems. Further improvements focus on driveability and fuel consumption.
The working areas of the project cover the following subjects:
Simulation:
o 0, 1D: Thermodynamic analysis, supercharging layout, gas exchange calculations
o 3D: Spray box investigations and mixture formation analysis
o further development of new and existing models Test bed:
o combustion process research carried out on single and multi-cylinder engines
o various fuels and their behaviour in alternative and conventional combustion modes
o combustion control in closed loop and model based applications Materials:
o advanced sinter technologies on mechanical strength, durability and acoustic.
The content of this paper presents activities of the scientific partner, the Institute for Internal Combustion Engines, Graz University of Technology.