Exhaust silencing system for internal combustion engine

摘要

The exhaust silencing system splits the exhaust gas (I) into two parallel streams, one of which has a silencer (2) tuned for damping low frequency sound, and the other has a silencer (3) tuned for high frequency sound. The gas outlet of the high frequency silencer has a valve (14), controlled in response to engine operating parameters. The valve is open at high engine speeds, and closed at low engine speeds. When the valve is closed, the high frequency silencer acts as a resonator. The silencers can be of the absorption and/or reflection type, can have one or more chambers, and can be built into a common housing. The silencer discharge pipes can feed separate tailpipes, or can converge into a common tailpipe.