EP0072274B1 - Silencieux ou atténuateur de son réactif pour débit pulse de gaz - Google Patents

Silencieux ou atténuateur de son réactif pour débit pulse de gaz Download PDF

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Publication number
EP0072274B1
EP0072274B1 EP82401322A EP82401322A EP0072274B1 EP 0072274 B1 EP0072274 B1 EP 0072274B1 EP 82401322 A EP82401322 A EP 82401322A EP 82401322 A EP82401322 A EP 82401322A EP 0072274 B1 EP0072274 B1 EP 0072274B1
Authority
EP
European Patent Office
Prior art keywords
rooms
ducts
sound
sets
silencer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP82401322A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0072274A1 (fr
Inventor
Daniel Richard
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Georges Hibon Sa Dite Ets
Original Assignee
Georges Hibon Sa Dite Ets
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Georges Hibon Sa Dite Ets filed Critical Georges Hibon Sa Dite Ets
Priority to AT82401322T priority Critical patent/ATE13082T1/de
Publication of EP0072274A1 publication Critical patent/EP0072274A1/fr
Application granted granted Critical
Publication of EP0072274B1 publication Critical patent/EP0072274B1/fr
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features
    • F01N13/18—Construction facilitating manufacture, assembly, or disassembly
    • F01N13/1838—Construction facilitating manufacture, assembly, or disassembly characterised by the type of connection between parts of exhaust or silencing apparatus, e.g. between housing and tubes, between tubes and baffles
    • F01N13/1844—Mechanical joints
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N1/00—Silencing apparatus characterised by method of silencing
    • F01N1/08—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling
    • F01N1/089—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling using two or more expansion chambers in series
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features
    • F01N13/009—Exhaust or silencing apparatus characterised by constructional features having two or more separate purifying devices arranged in series
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features
    • F01N13/18—Construction facilitating manufacture, assembly, or disassembly
    • F01N13/1888—Construction facilitating manufacture, assembly, or disassembly the housing of the assembly consisting of two or more parts, e.g. two half-shells
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N2450/00—Methods or apparatus for fitting, inserting or repairing different elements
    • F01N2450/24—Methods or apparatus for fitting, inserting or repairing different elements by bolts, screws, rivets or the like
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N2470/00—Structure or shape of exhaust gas passages, pipes or tubes
    • F01N2470/10—Tubes having non-circular cross section
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N2470/00—Structure or shape of exhaust gas passages, pipes or tubes
    • F01N2470/30—Tubes with restrictions, i.e. venturi or the like, e.g. for sucking air or measuring mass flow

Definitions

  • the present invention relates to a silencer or attenuator of its reactive sound, that is to say with reflection or echo of sound wave, for pulsed flow of gas subjected to medium and high frequencies, namely approximately 300 to 8000 Hz .
  • the invention proposes to solve it although, as we will see, this has been a concern for many technicians for decades. These technicians had to solve the elimination of medium and high frequencies ranging between 300 and 8000 Hz.
  • silencers based on the principle of absorption damping of noise by absorption (passive silencer)
  • the gases are brought in by means of tubes which have holes at the periphery through which the sound wave can exit while being distributed from uniformly and is absorbed to some extent by absorbent which surrounds these tubes.
  • absorption silencers are used in particular as main silencers to dampen a wide range of noise.
  • they have the drawback of being bulky because it is necessary to give the tubes which have holes a relatively large section to limit the speed of passage of the gases in order to avoid entrainment of absorbent materials which causes pollution of the gas and deterioration of the muffler.
  • reflection or baffle absorbers that operate on an active principle where the sound waves are reflected by attenuating the posterior waves.
  • the acoustic waves must propagate in plane waves.
  • conduits are provided which bring the gases into chambers or reflection spaces from which the gases can escape in order to flow more regularly with a strongly attenuated sound energy.
  • the principle used for the sound absorbers by reflection rests on the fact that the sound is reduced thanks to modifications of section and changes of direction. By virtue of the varied reactance encountered in each of the elements, there is an attenuation of the sound energy. For large gas flows, the muffler section is such that only low frequencies can be treated.
  • FIG. 1 of these drawings a chamber of section S, of length I, is shown, which is connected to two conduits of section s. It is recognized that such a chamber can absorb sound waves whose wavelength is in relation to the length 1 and corresponds to a frequency f 1 .
  • the attenuation efficiency is a function of the expansion ratio, that is to say the ratio of the S / s sections. It is immediately understood that it is advantageous to have a relatively small section S to limit the size of the chamber but that, on the other hand, the flow rate of the device is limited.
  • the chamber has a relatively large length 1 to attenuate a relatively small frequency f 1 .
  • the problem therefore comes down to obtaining the highest possible S / s ratio, the number of chambers of different dimensions in series as large as possible and, however, limiting the pressure losses and the bulk, all this by reducing the price of returns from the device.
  • an improvement consists in providing tapered chamber bottoms, as shown in dotted lines in FIG. 1, in order to reduce the pressure losses without however affecting efficiency.
  • the silencer or sound attenuator of the invention is characterized by a system of several identical assemblies arranged in parallel, connected to at least one intake manifold and / or one exhaust manifold, each of the assemblies being constituted by a succession of expansion chambers of different dimensions connected by an axial duct, each of the chambers having dimensions such as it is granted for a frequency domain to be attenuated while the connecting conduits have a small section compared to the section of the chambers.
  • Said chambers can be prismatic and / or cylindrical and their section depends on the upper frequency limit capable of being attenuated while their length depends on the frequency domain capable of being attenuated, it being understood that these latter frequencies are below the upper limit of frequencies to be processed. If they are cylindrical, they are preferably of revolution with frustoconical bottoms adapting to axial tubular conduits.
  • a very important characteristic of the invention resides in the fact that a system of several sets of chambers connected by conduits is produced, a system in which the lengths of the chambers and of the conduits are determined so that an alveolar nesting can be ensured elements which are offset from each other so that the chambers are placed at the level of the conduits of the adjacent assemblies and vice versa, so that the system occupies the minimum volume.
  • the first consists in making the silencer by sections perpendicular to the axis of the conduits and that said sections are assembled by known means in order to constitute a sound-absorbing block.
  • the sound-absorbing block can be either prismatic, generally parallelepipedic, or cylindrical.
  • the second consists in making the silencer by identical plane elements, in the form of plates each having in hollow, on their two faces, complementary parts of the assemblies connected by conduits, said complementary parts being arranged to adapt exactly to the corresponding parts of the adjacent planar elements for reconstructing the system of sets of chambers and conduits by means of assembly and relative positioning. It is more convenient for the planar elements to have, in hollow, on each of their faces, half of each assembly constituted by a section of the chambers and conduits along a diametral plane thereof, said elements comprising means of assembly by tie rods ensuring the juxtaposition and the tightening to thus constitute a blockplarallakipi conclusionsdique sound absorber.
  • the intake and exhaust manifolds consist of boxes respectively covering the inputs and outputs of the sound-absorbing block.
  • an elongated box is provided. the central part of which the sound damping block is placed, leaving upstream and downstream two chambers serving as collectors having a relatively large length for processing and damping the low frequencies.
  • This elongated box generally serves as a base for the machine producing the sound pulses of gas.
  • the embodiment of the invention allows a great ef, efficiency of the silencers since the S / s ratio is important and that the disadvantage of a small section s is avoided by arranging in parallel a large number of equivalent sets.
  • the diameter of the elementary silencers is calculated to allow propagation in plane waves up to high frequencies, 8000 Hz for example. It is possible to extend this limit at high frequencies by using elementary silencers of smaller diameters.
  • this device makes it possible to process high frequencies since it is possible to reduce the length of the rooms in a simple way. Finally, the cost price is considerably reduced, above all, as we have seen if the device is integrated into the base of the device.
  • Chamber 1 has a length II; chamber 2 has a length 1 2 ; chamber 3 has a length 1 3 .
  • FIG. 7 other assemblies 1 to 8a have been shown which are staggered relative to the assembly 1 to 8 in order to achieve a rigorous nesting of the different assemblies.
  • the conduit 4 has the same length as the chamber 1 a while the conduit 5a has the same length as the chamber 1 and the conduit 5 has the same length as the chamber 2a, that the conduit 6a has the same length as chamber 2 and that chambers 3a and 3 have the same length.
  • the conduits 7 and 7a, in the same way as the conduits 8 and 8a have different lengths to make up for the offset between the two assemblies.
  • the other sets are arranged in the same way as the sets 1 to 8, on the one hand and 1 a to 8a, on the other hand.
  • the damping block 10 is parallelepipedic and is composed of planar elements 11 (FIG. 8) which have in hollow on each of their faces a half of each set 1 to 8 and a half of each set 1 a to 8a , these sets of chambers 1, 2, 3, la, 2a, 3a and conduits 4, 5, 6, 7, 8, 5a, 6a, 7a and 8a being cut along a diametrical plane.
  • the elements 11 also include positioning means (not shown) to each other and assembly which are generally threaded rods with nuts which pass through the notches 14, 15, 16, 17.
  • FIG. 7 brings together the two embodiments, one with elements 11 arranged longitudinally along the joint planes such as 31 and 32, and the other by transverse elements such as 18 with joint planes 19 to 30. In the latter case, longitudinal tie rods are used.
  • transverse elements 18 With this last embodiment by transverse elements 18, it is also possible to use elements 181 (FIG. 10) which then have a circular section by staggered distribution of the sets of chambers and conduits as it is clearly represented in this same FIG. 10.
  • the damping block 10 is placed in the central part of an elongated box 33 leaving, upstream, an intake manifold 34 and, downstream, an exhaust manifold 35.
  • the manifold 35 is of elsewhere a chamber having a relatively large length for processing the low frequencies which are not processed in the damping block 10.
  • the box 33 is closed at both ends by irons U 37 and 38 which serve as feet for the assembly and whose upper wings 39 and 40 contribute to the fixing of a cover 41 which comprises a blocking element 42 of the block 10 The latter is also blocked by an angle 43 fixed to the bottom of the gutter 36.
  • This gutter decoupled from the box 33 by a viscoelastic product, serves as a double wall to reduce the acoustic radiation.
  • the admission of gases into the chamber 34 is done through the hole 44 while the exhaust from the chamber 35 is done through the exhaust tube 45 which also penetrates largely in overhang to the inside of the exhaust collecting chamber 35.
  • the gas path is moreover materialized by all the arrows in FIG. 12.
  • valve connection or an access hole 46 which can be plugged by a plate (not shown) which is fixed by the studs 47. It is also if provided cross members 48, 49, 50 which support the mechanics.
  • the box 33 is therefore massive and its inertia is considerably increased by the weight of the apparatus which rests thereon. This contributes to the improvement of sound absorption.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Silencers (AREA)
  • Pipe Accessories (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Gas Separation By Absorption (AREA)
EP82401322A 1981-07-23 1982-07-13 Silencieux ou atténuateur de son réactif pour débit pulse de gaz Expired EP0072274B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT82401322T ATE13082T1 (de) 1981-07-23 1982-07-13 Reaktiver schalldaempfer fuer pulsierenden gasstrom.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8114685 1981-07-23
FR8114685A FR2510184A1 (fr) 1981-07-23 1981-07-23 Silencieux ou attenuateur de son reactif pour debit pulse de gaz

Publications (2)

Publication Number Publication Date
EP0072274A1 EP0072274A1 (fr) 1983-02-16
EP0072274B1 true EP0072274B1 (fr) 1985-05-02

Family

ID=9260943

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82401322A Expired EP0072274B1 (fr) 1981-07-23 1982-07-13 Silencieux ou atténuateur de son réactif pour débit pulse de gaz

Country Status (4)

Country Link
EP (1) EP0072274B1 (enrdf_load_stackoverflow)
AT (1) ATE13082T1 (enrdf_load_stackoverflow)
DE (1) DE3263390D1 (enrdf_load_stackoverflow)
FR (1) FR2510184A1 (enrdf_load_stackoverflow)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI113892B (fi) 1998-09-30 2004-06-30 Metso Paper Inc Reaktiivinen äänenvaimennin teollisuuden ilmakanavia varten ja sen käyttö
KR100436620B1 (ko) * 2002-01-22 2004-06-22 주식회사 서진인스텍 공동식유량계
CN113425198B (zh) * 2021-07-22 2025-02-07 成都迈科高分子材料股份有限公司 用于吸尘器或扫地机器人的消音降噪装置及降噪方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE375411A (enrdf_load_stackoverflow) * 1930-11-20
DE815867C (de) * 1949-07-09 1951-10-04 Tydens Patenter Ab Vorrichtung an Schalldaempfern fuer Verbrennungsmotoren, Kompressoren u. dgl.
US2566939A (en) * 1950-05-02 1951-09-04 Howard R Johnson Muffler with plural side branch chambers
US2938593A (en) * 1957-10-14 1960-05-31 Meral O Miller Combination sound-deadening and gas-purifying apparatus

Also Published As

Publication number Publication date
EP0072274A1 (fr) 1983-02-16
ATE13082T1 (de) 1985-05-15
FR2510184B1 (enrdf_load_stackoverflow) 1985-04-19
FR2510184A1 (fr) 1983-01-28
DE3263390D1 (en) 1985-06-05

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