muffler

muffler, in automobiles, device designed to reduce the noise from the exhaust of an internal-combustion engine. When the exhaust gases from an internal-combustion engine are released directly into the atmosphere, they create a loud noise, caused by the passage of the exhaust gases from the high pressure of the cylinder to the normal pressure of the atmosphere. To eliminate or tone down the noise, the gases are led through a pipe to a muffler. Typically a muffler consists of a tubular metal jacket containing perforated pipes and chambers through which the exhaust gases flow before entering the atmosphere. The pipes and chambers are arranged so that the noise from the exhaust gases is reflected back toward the engine or back and forth among the chambers, reducing greatly the amount of noise that is radiated into the environment.

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muffler

US and Canadian any device designed to reduce noise, esp the tubular device containing baffle plates in the exhaust system of a motor vehicle

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muffler [′məf·lər]

(engineering)

A device to deaden the noise produced by escaping gases or vapors.

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sound attenuator

In ductwork, a device (usually prefabricated) especially designed to provide much greater sound attenuation than would be provided by an equal length of ductwork; the pressure drop through the device is greater than for an equal length of ductwork.