/muf"leuhr/, n.
1. a scarf worn around one's neck for warmth.
2. any of various devices for deadening sound, as the sound of escaping gases of an internal-combustion engine.
3. anything used for muffling.
4. Armor. a mittenlike glove worn with a mail hauberk.
[1525-35; MUFFLE + -ER1]

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▪ engine part
also called  silencer  

      device through which the exhaust gases from an internal-combustion engine are passed to attenuate (reduce) the airborne noise of the engine. To be efficient as a sound reducer, a muffler must decrease the velocity of the exhaust gases and either absorb sound waves or cancel them by interference with reflected waves coming from the same source.

      A typical sound-absorbing material used in a muffler is a thick layer of fine fibres; the fibres are caused to vibrate by the sound waves, thus converting the sound energy to heat. Mufflers that attenuate sound waves by interference are known as reactive mufflers. These devices generally separate the waves into two components that follow different paths and then come together again out of phase (out of step), thus canceling each other out and reducing the sound.

 In the typical reactive design shown in the illustration—>, the arrows indicate the flow of exhaust gas through a set of tubes and chambers inside the muffler. One important chamber is known as the Helmholtz resonator. This chamber is of a dimension carefully tuned to reflect and cancel sound waves of specified frequencies. In addition, the tubes can be perforated with small holes that allow the reflection and interference of sound waves of other frequencies. The result is the attenuation of sound across a range of desired frequencies.

      Mufflers of the straight-through type have a single tube with small holes connecting with annular chambers that are frequently stuffed with a sound-absorbing material.

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Universalium. 2010.

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Look at other dictionaries:

  • Muffler — Muf fler, n. 1. Anything used in muffling; esp., a scarf for protecting the head and neck in cold weather; a tippet. [1913 Webster] Fortune is painted blind, with a muffler above her eyes. Shak. [1913 Webster] 2. (Mus.) A cushion for terminating… …   The Collaborative International Dictionary of English

  • muffler — index damper (stopper) Burton s Legal Thesaurus. William C. Burton. 2006 …   Law dictionary

  • muffler — → mofle …   Diccionario panhispánico de dudas

  • muffler — (n.) 1530s as a kind of wrap for the throat, agent noun from MUFFLE (Cf. muffle) (v.); as an automobile exhaust system silencer, it is attested from 1895 …   Etymology dictionary

  • muffler — ► NOUN 1) a wrap or scarf worn around the neck and face. 2) a device for deadening the sound of a drum or other instrument. 3) N. Amer. a silencer for a motor vehicle exhaust …   English terms dictionary

  • muffler — [muf′lər] n. 1. a scarf worn around the throat, as for warmth 2. any of various devices for deadening noises; specif., an automotive exhaust device containing two perforated pipes packed in sound deadening material …   English World dictionary

  • Muffler — This article is about the exhaust system component. For other uses, see Muffler (disambiguation). Muffler(silver) and exhaust pipe on a Ducati 695 motorcycle A muffler (or silencer in British English) is a device for reducing the amount of noise… …   Wikipedia

  • muffler — [1] A unit through which the exhaust gases are passed to quiet the sounds of the running engine. The British term is silencer. [2] A hollow, tubular device used in the discharge line of some systems to muffle the thumping sounds made by the… …   Dictionary of automotive terms

  • muffler — [[t]mʌ̱flə(r)[/t]] mufflers 1) N COUNT A muffler is the same as a scarf. [OLD FASHIONED] 2) N COUNT A muffler is a device on a car exhaust that makes it quieter. [AM] (in BRIT, use silencer) …   English dictionary

  • muffler — UK [ˈmʌflə(r)] / US [ˈmʌflər] noun [countable] Word forms muffler : singular muffler plural mufflers 1) old fashioned a long piece of cloth that you wrap around your neck to keep it warm 2) American a silencer on a vehicle …   English dictionary

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