GB2464746A - Noise reduction in ducted air systems - Google Patents
Noise reduction in ducted air systems Download PDFInfo
- Publication number
- GB2464746A GB2464746A GB0819913A GB0819913A GB2464746A GB 2464746 A GB2464746 A GB 2464746A GB 0819913 A GB0819913 A GB 0819913A GB 0819913 A GB0819913 A GB 0819913A GB 2464746 A GB2464746 A GB 2464746A
- Authority
- GB
- United Kingdom
- Prior art keywords
- duct
- composite material
- airstream
- syntactic
- syntactic composite
- 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.)
- Withdrawn
Links
- 239000002131 composite material Substances 0.000 claims abstract description 42
- 239000000463 material Substances 0.000 claims abstract description 17
- 239000002245 particle Substances 0.000 claims abstract description 6
- 238000000034 method Methods 0.000 claims abstract description 5
- 238000011144 upstream manufacturing Methods 0.000 claims description 5
- 238000005054 agglomeration Methods 0.000 claims description 3
- 230000002776 aggregation Effects 0.000 claims description 3
- 238000010521 absorption reaction Methods 0.000 abstract description 3
- 238000004378 air conditioning Methods 0.000 abstract description 3
- 238000010438 heat treatment Methods 0.000 abstract description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 2
- 230000002745 absorbent Effects 0.000 description 3
- 239000002250 absorbent Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000006260 foam Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000001143 conditioned effect Effects 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F7/00—Ventilation
- F24F7/04—Ventilation with ducting systems, e.g. by double walls; with natural circulation
- F24F7/06—Ventilation with ducting systems, e.g. by double walls; with natural circulation with forced air circulation, e.g. by fan positioning of a ventilator in or against a conduit
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04F—FINISHING WORK ON BUILDINGS, e.g. STAIRS, FLOORS
- E04F17/00—Vertical ducts; Channels, e.g. for drainage
- E04F17/04—Air-ducts or air channels
-
- 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
-
- 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
- F16L55/027—Throttle passages
- F16L55/02745—Throttle passages by passing through a mass of particles or a porous member
-
- 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
- F16L55/0336—Noise absorbers by means of sound-absorbing materials
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/02—Ducting arrangements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F8/00—Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying
- F24F8/10—Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying by separation, e.g. by filtering
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
- F24F2013/242—Sound-absorbing material
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Duct Arrangements (AREA)
Abstract
A ducted air system such as provided in buildings and water borne vessels for heating, ventilating or air conditioning and a method of noise reduction wherein noise reduction is effected by the provision within a walled duct (10) through which the airstream (11) passes, of a syntactic composite material (12) and through which a substantial portion of the volume of the airstream is constrained to flow before exiting the duct. The material (12), being of particulate form causes the airstream to flow through the interstices between the particles of the material thus assisting in the absorption of noise generated within the system.
Description
NOISE REDUCTION IN DUCTED AIR SYSTEMS
This invention concerns ducted air systems comprising a walled duct through which an airstream passes from a source such as a heating, ventilation or air conditioning unit, to a remote location. Particularly, but not exclusively, the invention concerns such systems incorporated in buildings and in water borne vessels where considerable noise is generated by the unit producing the ducted air, the noise being generated also by the velocity of the air travelling through the walled duct and by resonance occurring within the duct casing. Even in systems in which the duct is of considerable volume as required to transfer sufficient air volume to a remote location, little or no noise reduction is achieved by the increased volume of the duct.
It is known to line the duct with a sound absorbent material but while reducing the effects of resonance, the lining has little or no effect upon the noise generated by the source of the airstream which sound is carried by the air passing along the duct.
It is an object of the present invention to provide a ducted air system in which substantial noise reduction is achieved without loss of volume of the air supplied by the system.
According to the present invention there is provided a ducted air system comprising a walled duct through which an airstream passes from a source to a remote location; characterised by the provision, within the duct, of a syntactic composite material; and in that said material is so disposed within the duct that at least a portion of the volume of said airstream is constrained to flow through the syntactic composite material before exiting the duct.
The syntactic composite material may be so disposed within the duct that the entire volume of the airstream is constrained to flow through the syntactic composite material before exiting the duct.
The syntactic composite material may be disposed at or adjacent an outlet of the duct at said remote location.
The syntactic composite material may occupy the whole of an outlet of the duct at said remote location.
The syntactic composite material may occupy the entire volume of an enlarged outlet of the duct at said remote location.
The enlarged outlet of the duct may include an expansion chamber located upstream of the syntactic composite material.
Baffle means may be provided within the duct to direct the airstream preferentially towards and through the syntactic composite material.
The syntactic composite material may be an agglomeration of particles bonded together to form a gas-permeable mass.
Further according to the present invention there is provided a method of absorbing sound in a ducted air system comprising a walled duct through which an airstream passes between a source and a remote location; characterised by the steps of providing within the duct a syntactic composite material and directing at least a portion of the volume of said airstream through the syntactic composite material before exiting the duct.
The entire volume of the airstream may be constrained to flow through the syntactic composite material before exiting the duct.
The airstream may flow through an expansion chamber before passing through the syntactic composite material.
The airstream may be directed by baffle means preferentially towards and through the syntactic composite material.
Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which: Fig. 1 illustrates an outlet region of a ducted air system incorporating a syntactic composite material in accordance with the invention; Fig. 2 shows syntactic composite material disposed within an enlarged outlet of the duct; Fig. 3 shows an expansion chamber in the outlet region of the duct upstream of the syntactic composite material; and Fig. 4 illustrates the use of baffle means to direct the airstream preferentially through the syntactic composite material.
Referring now to Fig. 1, in a first embodiment there is illustrated a duct 10 through which an airstream passes in the direction of arrow 11 towards an outlet which may incorporate a wall mounted grille 13. In this and the following embodiments it will be assumed, for example, that the ducted air system is connected to an air conditioning unit to provide conditioned and temperature adjusted air to a space within a building or ship.
Located in, and occupying the whole of an outlet region of duct 10 is a lightweight syntactic composite material 12 of the kind comprising an agglomeration of expanded glass granules made form recycled glass and having a particle size range typically between 1 -4mm diameter, bonded together using sodium silicate solution, dried and heated to a temperature in excess of 700 to form a lightweight syntactic foam. The properties of the material 12 are such that no significant loss of volume of the airflow is experienced as the air passes through the interstices around the particles within the syntactic foam. The effect of the airstream travelling around a torturous path through the material is that considerable sound absorption is achieved with the result that the noise generated at the source of the system, which travels along the duct 10 with the airstream is absorbed by the material 13 before the air passes through the grille 12 into the room.
The sound absorbent properties of the material serve also to absorb any noise created by resonance of the material of the duct 10. Whilst the material 12 permits the passage of the air, its velocity is reduced by being constrained to flow around the particles of the material, and again this reduction in velocity assists in the absorption of sound.
Preferably, the material 12 is of a non-combustible nature and thus will serve as a flash-proof acoustic screen able to prevent the transmission of fire through the duct 1 0 thus to prevent the spread of fire from place to place within a building.
Referring now to Fig. 2 in some cases it may be required to provide an increased volume of the syntactic composite material 12 so that the duct 10, in this case, has an enlarged outlet 14 filled entirely with the syntactic composite material.
Referring now to Fig. 3 in some cases it might be preferred to provide an expansion chamber 15 upstream of the syntactic composite material within the enlarged outlet 14 of the duct 10. Thus, the velocity of the airstream is reduced prior to passage through the syntactic composite material.
Referring now to Fig. 4, baffle means 16 may be provided within the outlet region of the duct 10 in order to spread the flow of the airstream and thus direct it evenly and preferentially through the syntactic composite material.
It is not intended to limit the invention to the above examples only, further variations being possible without departing from the scope of the invention. For example, the syntactic composite material may be provided upstream of the outlet and/or at spaced locations along the duct. In cases in which the material is provided at spaced locations along the duct, the density of the material may differ from one location to another in order to control the velocity of the airstream and to provide noise absorbency where it is most needed.
If required, all or part of the wall of the duct may be lined with a layer of syntactic composite material or other sound absorbent material to reduce noise generated by resonance within the material of the duct.
Claims (11)
- CLAIMS1. A ducted air system comprising a walled duct through which an airstream passes from a source to a remote location; characterised by the provision within the duct of a syntactic composite material; and in that said material is so disposed within the duct that at least a portion of the volume of said airstream is constrained to flow through the syntactic composite material before exiting the duct.
- 2. A ducted air system according to claim 1 wherein the syntactic composite material is so disposed within the duct that the entire volume of the airstream is constrained to flow through the syntactic composite material.
- 3. A ducted air system according to claim 1 or claim 2 wherein the syntactic composite material is disposed at or adjacent an outlet of the duct at said remote location.
- 4. A ducted air system according to any preceding claim wherein the syntactic composite material occupies the entire volume of an outlet of the duct at said remote location.
- 5. A ducted air system according to any preceding claim wherein the syntactic composite material occupies the entire volume of an enlarged outlet of the duct at said remote location.
- 6. A ducted air system according to claim 5 wherein the enlarged outlet of the duct includes an expansion chamber located upstream of the syntactic composite material.
- 7. A ducted air system according to any preceding claim including baffle means provided within the duct to direct the airstream preferentially towards and through the syntactic composite material.
- 8. A ducted air system according to any preceding claim wherein the syntactic composite material is an agglomeration of particles bonded together to form a gas-permeable mass.
- 9. A method of absorbing sound in a ducted air system comprising a walled duct through which an airstream passes between a source and a remote location; characterised by the steps of providing within the duct a syntactic composite material and directing at least a portion of the volume of said airstream to flow through the syntactic composite material before exiting the duct.
- 10. A method according to claim 9 wherein the entire volume of the airstream is constrained to flow through the syntactic composite material before exiting the duct.
- 11. A method according to claim 9 or claim 10 wherein the airstream is caused to flow through an expansion chamber before entering the syntactic composite material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/GB2009/051427 WO2010046707A1 (en) | 2008-10-24 | 2009-10-22 | Ducted air system with syntactic material placed adjacent an outlet for noise attenuation and associated method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GBGB0819534.9A GB0819534D0 (en) | 2008-10-24 | 2008-10-24 | Noise reduction in ducted air systems |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB0819913D0 GB0819913D0 (en) | 2008-12-10 |
| GB2464746A true GB2464746A (en) | 2010-04-28 |
Family
ID=40133773
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GBGB0819534.9A Ceased GB0819534D0 (en) | 2008-10-24 | 2008-10-24 | Noise reduction in ducted air systems |
| GB0819913A Withdrawn GB2464746A (en) | 2008-10-24 | 2008-10-30 | Noise reduction in ducted air systems |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GBGB0819534.9A Ceased GB0819534D0 (en) | 2008-10-24 | 2008-10-24 | Noise reduction in ducted air systems |
Country Status (2)
| Country | Link |
|---|---|
| GB (2) | GB0819534D0 (en) |
| WO (1) | WO2010046707A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015122832A1 (en) * | 2014-02-11 | 2015-08-20 | Lindab Ab | Ventilation device with varying air velocity |
| EP3222928A1 (en) * | 2016-03-24 | 2017-09-27 | Sigarth AB | Ventilation unit |
| CN109780317A (en) * | 2019-01-07 | 2019-05-21 | 珠海市广源信科技有限公司 | A kind of speed governing valve pressure compensator |
| DE102015105555B4 (en) | 2015-04-13 | 2019-05-23 | Odenwald-Chemie Gmbh | Device for flow calming and vehicle |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109974363B (en) * | 2017-12-27 | 2024-04-19 | 海尔智家股份有限公司 | Air-cooled refrigerator |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2422108A1 (en) * | 1974-05-08 | 1975-11-27 | Daume Regelarmaturen W | Choke device for gaseous media - provides multi-stage medium expansion by means of expansion component containing filler bodies |
| US4695343A (en) * | 1983-09-12 | 1987-09-22 | General Motors Corporation | Method of reinforcing a structural member |
| US5036948A (en) * | 1989-01-12 | 1991-08-06 | Heidelberger Druckmaschinen Ag | Sound absorption device or muffler for blow nozzles |
| US5313803A (en) * | 1991-09-14 | 1994-05-24 | Kesslertech Gmbh | Air conditioning system for human-occupied spaces |
| FR2733037A1 (en) * | 1995-04-14 | 1996-10-18 | Gibert Jean Pierre | Ventilator with deformable chamber fitting on air inlet vent deflector |
| DE19737799A1 (en) * | 1996-10-09 | 1998-04-23 | Mando Machine Co Ltd | Silencer for high-pressure output of compressor in vehicle air conditioner |
| US20050051382A1 (en) * | 2003-09-10 | 2005-03-10 | Voss Automotive Gmbh: | Pneumatic blow-off silencer |
| US20050281999A1 (en) * | 2003-03-12 | 2005-12-22 | Petritech, Inc. | Structural and other composite materials and methods for making same |
| EP1628084A1 (en) * | 2003-04-23 | 2006-02-22 | Tosho Engineering Co., Ltd. | Ventilator |
| DE202006015493U1 (en) * | 2006-10-09 | 2006-12-07 | Voss Automotive Gmbh | Damper in pneumatic pressure system damps noise caused by pressure discharge flows from pressure side to atmosphere side |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0370932A (en) * | 1989-08-08 | 1991-03-26 | Mitsubishi Electric Home Appliance Co Ltd | Muffler |
| US5504281A (en) * | 1994-01-21 | 1996-04-02 | Minnesota Mining And Manufacturing Company | Perforated acoustical attenuators |
| SE0302201D0 (en) * | 2003-08-13 | 2003-08-13 | Airson Ab | Air Supply Arrangement |
| US20080185220A1 (en) * | 2006-11-14 | 2008-08-07 | Caterpillar Inc. | Method of using syntactic foam to reduce noise and machine using same |
-
2008
- 2008-10-24 GB GBGB0819534.9A patent/GB0819534D0/en not_active Ceased
- 2008-10-30 GB GB0819913A patent/GB2464746A/en not_active Withdrawn
-
2009
- 2009-10-22 WO PCT/GB2009/051427 patent/WO2010046707A1/en active Application Filing
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2422108A1 (en) * | 1974-05-08 | 1975-11-27 | Daume Regelarmaturen W | Choke device for gaseous media - provides multi-stage medium expansion by means of expansion component containing filler bodies |
| US4695343A (en) * | 1983-09-12 | 1987-09-22 | General Motors Corporation | Method of reinforcing a structural member |
| US5036948A (en) * | 1989-01-12 | 1991-08-06 | Heidelberger Druckmaschinen Ag | Sound absorption device or muffler for blow nozzles |
| US5313803A (en) * | 1991-09-14 | 1994-05-24 | Kesslertech Gmbh | Air conditioning system for human-occupied spaces |
| FR2733037A1 (en) * | 1995-04-14 | 1996-10-18 | Gibert Jean Pierre | Ventilator with deformable chamber fitting on air inlet vent deflector |
| DE19737799A1 (en) * | 1996-10-09 | 1998-04-23 | Mando Machine Co Ltd | Silencer for high-pressure output of compressor in vehicle air conditioner |
| US20050281999A1 (en) * | 2003-03-12 | 2005-12-22 | Petritech, Inc. | Structural and other composite materials and methods for making same |
| EP1628084A1 (en) * | 2003-04-23 | 2006-02-22 | Tosho Engineering Co., Ltd. | Ventilator |
| US20050051382A1 (en) * | 2003-09-10 | 2005-03-10 | Voss Automotive Gmbh: | Pneumatic blow-off silencer |
| DE202006015493U1 (en) * | 2006-10-09 | 2006-12-07 | Voss Automotive Gmbh | Damper in pneumatic pressure system damps noise caused by pressure discharge flows from pressure side to atmosphere side |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015122832A1 (en) * | 2014-02-11 | 2015-08-20 | Lindab Ab | Ventilation device with varying air velocity |
| WO2015122831A1 (en) * | 2014-02-11 | 2015-08-20 | Lindab Ab | Ventilation device with reduced sound generation |
| US10443887B2 (en) | 2014-02-11 | 2019-10-15 | Lindab Ab | Ventilation device with varying air velocity |
| DE102015105555B4 (en) | 2015-04-13 | 2019-05-23 | Odenwald-Chemie Gmbh | Device for flow calming and vehicle |
| EP3222928A1 (en) * | 2016-03-24 | 2017-09-27 | Sigarth AB | Ventilation unit |
| CN109780317A (en) * | 2019-01-07 | 2019-05-21 | 珠海市广源信科技有限公司 | A kind of speed governing valve pressure compensator |
Also Published As
| Publication number | Publication date |
|---|---|
| GB0819913D0 (en) | 2008-12-10 |
| GB0819534D0 (en) | 2008-12-03 |
| WO2010046707A1 (en) | 2010-04-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |