Efficient Exhaust Silencers for Downsized Gasoline Engines 2012-01-1563
In recent years, the ANC technology was adapted for intake and
exhaust systems on several passenger vehicles with a variety of
diesel and gasoline engines. In these predevelopment activities,
the active components (actuators, electronic hardware and software)
were rigorously improved and its durability professionally
validated leading to an increased system performance even under
very harsh conditions. Depending on the customer targets, this
yielded several benefits when compared to conventional exhausts.
For example, a passive conventional dual exhaust system of a highly
efficient 4-cylinder gasoline engine could be replaced by an active
single exhaust line without compromising on the acoustic targets
but saving a considerably amount of design space and weight. In
particular, the space advantage can be utilized to create
innovative exhaust layouts.
To support future downsizing of engines, for example, an
ultra-compact exhaust layout is proposed. By concentrating all
parts of the exhaust close to the engine, e.g., within the engine
bay, further space in the underbody of a vehicle is released and
can be used for installing other equipment (e.g., batteries in
hybrid electric vehicles) or optimizing underbody flow conditions.
Consequently, the active exhaust technology leads to an overall
optimization of the vehicle design and could eventually support an
even lower CO₂ emission of future vehicles with downsized and