Exhaust silencer for engine of racing car, provides minimal acoustic damping at low engine speeds and greater damping via gas permeable damping filling at high engine speeds

摘要

The exhaust gas from the engine enters the silencer (1) via a tapered first pipe (6). At low engine speeds, the gas passes from the end of the first pipe into the middle pipe (10). It then passes out of the silencer via the third pipe (7). At higher speeds and hence higher pressures, most of the gas passes through perforations in the first tube into a filling (9) of acoustic damping material. It then passes through perforations in the middle and end tubes before leaving (5) the silencer.