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The worldwide focus on reducing the emissions, fuel and lubricant consumption in engines is leading engineers to consider the crankcase ventilation and oil mist separation system as an important means of control. In today's passenger cars the oil mist separation systems mainly use the inertia effect (e.g. labyrinth, cyclone etc.). In this work a new concept for oil mist separation will be presented. The concept combines the assembled camshaft with an oil mist separator. This allows for a pre-separation effect through centrifugal forces at the entry point to the rotating camshaft and an additional efficiency gain thru the swirl generator, which is integrated into the camshaft.

Reducing evaporation emission is one of the most important targets during vehicle development nowadays. Apart from the emissions while the vehicle is in operation, evaporation emissions occur after the engine is turned off. Up to 30 % of these emissions can originate from the Air Intake System (AIS). Today, Hydro Carbon Adsorbers (HCA) are already used as a part of the AIS to reduce evaporation emissions [1], [2]. Usually the HCA contains activated carbon or zeolite. HC emissions are adsorbed by the HCA during and after the engine shut down. When the engine is running, the HCA is purged with the intake air. The HC storage principle is well known for carbon canisters [3]. HCAs were initially designed for existing AIS. So far, the pressure drop of the system was considered to be the most important design parameter while designing the AIS. Due to government regulations, more advanced requirements are established and hence sophistication in design is needed to meet new targets.

As a result of the new exhaust gas legislation the significance of crankcase ventilation systems in combustion engines has drastically increased. Oil mist separation, which is a part of the crankcase ventilation systems, influences numerous engine processes, which directly or indirectly impact the emissions of newly developed combustion engines. The oil mist separator’s task is to retain the liquid oil parts and to return them to the oil sump. Thus, the oil mist separator reduces oil consumption and emissions. By continuously optimizing the oil consumption at different sources, oil separation from the blow-by gas is gaining significant influence on the overall oil carry consumption. In addition to reducing oil consumption, the development of highly efficient oil separation systems in crankcase ventilation it also rising in importance due to additional concerns.