| 摘要 |
In-line exhaust systems comprise an exhaust pipe (14), and a sound-attenuating baffle (34) in the exhaust pipe. The baffle has one or more baffle plates extending across the gas flow channel, at least one at an oblique angle. Each plate has an array of apertures (42A, 42B) therethrough. The plates are joined to each other, preferably in edge-to-edge relationship, preferably forming included angles with each other and forming preferably different, oblique angles to the longitudinal axis. In preferred embodiments, plate aperture area increases, plate-to-plate, along the direction of advance of gases in the exhaust system. A backwash valve (45) can lie over one of the baffle plates. The exhaust system can include a water jacket, and optionally an outer sound attenuation chamber. The baffle is preferably 36 or less inches long, the exhaust system reducing noise by at least 3 decibels. |
