GB1512014A - Method of attenuating longitudinal compression waves travelling in a gas filled duct - Google Patents

Method of attenuating longitudinal compression waves travelling in a gas filled duct

Info

Publication number
GB1512014A
GB1512014A GB27679/74A GB2767974A GB1512014A GB 1512014 A GB1512014 A GB 1512014A GB 27679/74 A GB27679/74 A GB 27679/74A GB 2767974 A GB2767974 A GB 2767974A GB 1512014 A GB1512014 A GB 1512014A
Authority
GB
United Kingdom
Prior art keywords
duct
compensate
linearity
june
gas filled
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
GB27679/74A
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.)
University of Leeds Industrial Services Ltd
Original Assignee
University of Leeds Industrial Services Ltd
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 University of Leeds Industrial Services Ltd filed Critical University of Leeds Industrial Services Ltd
Priority to GB27679/74A priority Critical patent/GB1512014A/en
Priority to NO752163A priority patent/NO752163L/no
Priority to ZA00753895A priority patent/ZA753895B/en
Priority to SE7507087A priority patent/SE7507087L/en
Priority to AU82325/75A priority patent/AU491349B2/en
Priority to DE19752527642 priority patent/DE2527642A1/en
Priority to BE157551A priority patent/BE830489A/en
Priority to FR7519519A priority patent/FR2275722A1/en
Publication of GB1512014A publication Critical patent/GB1512014A/en
Expired legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/04—Devices damping pulsations or vibrations in fluids
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/02—Energy absorbers; Noise absorbers
    • F16L55/033—Noise absorbers
    • F16L55/0333—Noise absorbers by means of an active system
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1781—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions
    • G10K11/17813—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions characterised by the analysis of the acoustic paths, e.g. estimating, calibrating or testing of transfer functions or cross-terms
    • G10K11/17819—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions characterised by the analysis of the acoustic paths, e.g. estimating, calibrating or testing of transfer functions or cross-terms between the output signals and the reference signals, e.g. to prevent howling
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17857—Geometric disposition, e.g. placement of microphones
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1787—General system configurations
    • G10K11/17873—General system configurations using a reference signal without an error signal, e.g. pure feedforward
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/112—Ducts
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3011—Single acoustic input
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3039—Nonlinear, e.g. clipping, numerical truncation, thresholding or variable input and output gain
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/50—Miscellaneous
    • G10K2210/506—Feedback, e.g. howling

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Mechanical Engineering (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Duct Arrangements (AREA)

Abstract

1512014 Silencing gaseous currents UNIVERSITY OF LEEDS INDUSTRIAL SERVICES Ltd 20 June 1975 [21 June 1974] 27679/74 Heading FIB In order to compensate for frequency/phase non-linearity in analog components of an interference silencer comprising input 5, 7 and output 17 transducers and a digital phase shift arrangement 13, 14, 15, a compensating circuit 12 is included to generate an inverse transfer function to compensate for non-linear components. Amplitude/phase non-linearity may be similarly compensated. The input transducer 5 may be a compliantly mounted directional microphone and a second microphone 7 may be provided to compensate for feed-back effects. The output transducers may be a loud speaker 17 mounted, through a flexible connection 19, in the branch duct 1 and may be separated from the duct gas by a diaphragm. Alternatively a single loud speaker or an array may be mounted on the walls of the duct 3 itself.
GB27679/74A 1974-06-21 1974-06-21 Method of attenuating longitudinal compression waves travelling in a gas filled duct Expired GB1512014A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
GB27679/74A GB1512014A (en) 1974-06-21 1974-06-21 Method of attenuating longitudinal compression waves travelling in a gas filled duct
NO752163A NO752163L (en) 1974-06-21 1975-06-17
ZA00753895A ZA753895B (en) 1974-06-21 1975-06-17 Method of attenuating noise
SE7507087A SE7507087L (en) 1974-06-21 1975-06-19 PROCEDURE FOR DAMPING WAVES IN GASES.
AU82325/75A AU491349B2 (en) 1974-06-21 1975-06-20 Method of attenuating noise
DE19752527642 DE2527642A1 (en) 1974-06-21 1975-06-20 PROCESS AND DEVICE FOR DAMPING LONGITUDINAL PRESSURE WAVES IN GAS LINES
BE157551A BE830489A (en) 1974-06-21 1975-06-20 NOISE MITIGATION PROCESS
FR7519519A FR2275722A1 (en) 1974-06-21 1975-06-23 NOISE MITIGATION PROCESS

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB27679/74A GB1512014A (en) 1974-06-21 1974-06-21 Method of attenuating longitudinal compression waves travelling in a gas filled duct

Publications (1)

Publication Number Publication Date
GB1512014A true GB1512014A (en) 1978-05-24

Family

ID=10263521

Family Applications (1)

Application Number Title Priority Date Filing Date
GB27679/74A Expired GB1512014A (en) 1974-06-21 1974-06-21 Method of attenuating longitudinal compression waves travelling in a gas filled duct

Country Status (7)

Country Link
BE (1) BE830489A (en)
DE (1) DE2527642A1 (en)
FR (1) FR2275722A1 (en)
GB (1) GB1512014A (en)
NO (1) NO752163L (en)
SE (1) SE7507087L (en)
ZA (1) ZA753895B (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4473906A (en) * 1980-12-05 1984-09-25 Lord Corporation Active acoustic attenuator
FR2783869A1 (en) * 1998-09-24 2000-03-31 Ecia Equip Composants Ind Auto Noise cancellation system for vehicle exhaust includes microphone connected to computer generating anti-noise for application to compensating loudspeaker
WO2001083122A1 (en) * 2000-05-04 2001-11-08 Thorn Security Limited Method and apparatus for equalising transfer functions of linear electro-acoustic systems
FR2843999A1 (en) * 2002-09-03 2004-03-05 Comptoir De La Technologie ACTIVE DEVICE FOR ATTENUATING MOUTH NOISE AT AN EXHAUST OR INTAKE DUCT
GB2399141A (en) * 2003-03-04 2004-09-08 Visteon Global Tech Inc Variable tuned resonator

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2386881A1 (en) * 1977-04-05 1978-11-03 Sound Attenuators Ltd Active sound attenuation using secondary wave - has stored programme used to obtain signal representing secondary wave
EP0040462A1 (en) * 1980-05-16 1981-11-25 Bose Corporation Electroacoustical audible noise reducing apparatus
DE4441217C2 (en) * 1993-12-17 1998-09-10 Voith Sulzer Papiermasch Gmbh Method for damping pressure surges and device for carrying out the method
FR2740599B1 (en) 1995-10-30 1997-12-19 Technofirst ACTIVE ACOUSTIC MITIGATION DEVICE INTENDED TO BE ARRANGED WITHIN A DUCT, PARTICULARLY FOR SOUNDPROOFING A VENTILATION AND / OR AIR CONDITIONING NETWORK
DE10021031A1 (en) * 2000-05-02 2001-11-08 Mann & Hummel Filter Line system with electromechanical transducer for generating a correction noise

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4473906A (en) * 1980-12-05 1984-09-25 Lord Corporation Active acoustic attenuator
FR2783869A1 (en) * 1998-09-24 2000-03-31 Ecia Equip Composants Ind Auto Noise cancellation system for vehicle exhaust includes microphone connected to computer generating anti-noise for application to compensating loudspeaker
WO2001083122A1 (en) * 2000-05-04 2001-11-08 Thorn Security Limited Method and apparatus for equalising transfer functions of linear electro-acoustic systems
GB2381991A (en) * 2000-05-04 2003-05-14 Thorn Security Method and apparatus for equalising transfer functions of linear electro-acoustic systems
GB2381991B (en) * 2000-05-04 2004-03-24 Thorn Security Method and apparatus for equalising transfer functions of linear electro-acoustic systems
FR2843999A1 (en) * 2002-09-03 2004-03-05 Comptoir De La Technologie ACTIVE DEVICE FOR ATTENUATING MOUTH NOISE AT AN EXHAUST OR INTAKE DUCT
WO2004022931A1 (en) * 2002-09-03 2004-03-18 Comptoir De La Technologie Active vent noise reduction device for use with an exhaust or intake pipe
GB2399141A (en) * 2003-03-04 2004-09-08 Visteon Global Tech Inc Variable tuned resonator
US6792907B1 (en) 2003-03-04 2004-09-21 Visteon Global Technologies, Inc. Helmholtz resonator

Also Published As

Publication number Publication date
FR2275722B1 (en) 1981-06-19
BE830489A (en) 1975-10-16
DE2527642A1 (en) 1976-01-08
FR2275722A1 (en) 1976-01-16
ZA753895B (en) 1976-05-26
AU8232575A (en) 1976-12-23
NO752163L (en) 1975-12-23
SE7507087L (en) 1975-12-22

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Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PCNP Patent ceased through non-payment of renewal fee