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The tightening of the emission legislation and political and social demands for sustainable mobility are forcing the automotive industry to develop complex, high precision mechatronic drive systems. The increasing precision of mechatronic components generally leads to an increase in structural excitation and thus to a rise in noise. The so-called ticking of the fuel injection system has a rather low sound pressure level compared to the residual engine noise. Nevertheless, the impulsive and high frequency noise character leads to a decline concerning the perception of comfort and sound quality. In order to identify the sound quality of fuel injection systems as a frontloading measure, a system test bench has been developed which represents the structure-borne and airborne sound radiation of the stand-alone injection system in a close to series configuration.

In coming years a special focus in the field of GDI engines will be on downsized concepts and highly-charged gasoline direct injection engines. This is due to stricter emission laws, higher customer requirements, greater environmental awareness as well as high demands on materials and resources. Especially at cold start, catalyst heating and warm up operation GDI engines have an issue with oil dilution. Fuel gets into the oil pan and is mixed with the engine oil so that the physical and chemical properties of the engine oil are changed. Adjusting engine operating points to higher mean effective pressures in downsizing concepts also an additional increase of the fuel input into the engine oil occurs. At the University of Applied Sciences Regensburg measurements were carried out at a direct injected gasoline engine with lateral injector position.

New trends in the development of combustion engines lead to changed engine operating conditions which also result in changed loads of the engine parts and functional components. The application of regenerative fuels and new exhaust after- treatment systems can for example lead to an increased input of fuel into the engine oil. Oil dilution is an issue that impacts the engine operation and life cycle and therefore gains importance during the development process of combustion engines. In order to improve oil dilution to preclude destructive amounts of fuel in the oil it is necessary to investigate and optimize the fuel in oil sorption and desorption processes. At the University of Applied Sciences Regensburg a new measurement technique has been developed that realizes the online analysis of the fuel quantity in the engine oil.

The emission reduction potential of high boost and high injection pressures was investigated on a 4-cylinder small bore diesel engine at high rates of exhaust gas recirculation. For this reason an external boosting system was built up, which allowed to generate the desired boost pressure independent from the engine's operating point. In order to simulate conditions comparable to a real turbocharged engine, also the influence of the turbine on the exhaust back pressure was considered. The whole measurement campaign was carried out at two load points (low- and mid-load), which represent characteristic engine operating points of the Urban Driving Cycle (UDC). On the one hand could be shown, that there is an enormous potential in the reduction of particulate matter (PM) up to 75 % and of carbon monoxide (CO) up to 15 % at the mid-load point by increasing the boost pressure.

Environmental issues have a significant influence on the development of modern combustion engines. Particularly the tightening of emission limits in Europe and the USA have to be considered in the development process. One issue that influences the emissions of engines is the oil consumption of the engine and thus the reduction of the oil consumption of combustion engines has gained importance in recent years. In order to optimize the oil consumption of the engine a measurement technique is needed that allows a very accurate detection of the engine oil consumption for steady state as well as for transient engine operation points. Since conventional measurement techniques provide only limited accuracy at long measuring times and are only applicable for steady state engine operation new methods for the online detection of the engine oil consumption have to be established. New methods for the oil consumption measurement are the tracer methods.