CN113685614A - Structure for reducing dynamic response of thin-wall ventilation pipe - Google Patents

Structure for reducing dynamic response of thin-wall ventilation pipe Download PDF

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Publication number
CN113685614A
CN113685614A CN202110905171.9A CN202110905171A CN113685614A CN 113685614 A CN113685614 A CN 113685614A CN 202110905171 A CN202110905171 A CN 202110905171A CN 113685614 A CN113685614 A CN 113685614A
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CN
China
Prior art keywords
skin
ventilation pipe
ventilation
thin
dynamic response
Prior art date
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Granted
Application number
CN202110905171.9A
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Chinese (zh)
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CN113685614B (en
Inventor
沈重
戴亚光
陈忠明
宋恩鹏
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Shenyang Aircraft Design and Research Institute Aviation Industry of China AVIC
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Shenyang Aircraft Design and Research Institute Aviation Industry of China AVIC
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Priority to CN202110905171.9A priority Critical patent/CN113685614B/en
Publication of CN113685614A publication Critical patent/CN113685614A/en
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L3/00Supports for pipes, cables or protective tubing, e.g. hangers, holders, clamps, cleats, clips, brackets
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/02Energy absorbers; Noise absorbers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/02Energy absorbers; Noise absorbers
    • F16L55/033Noise absorbers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/02Energy absorbers; Noise absorbers
    • F16L55/033Noise absorbers
    • F16L55/0336Noise absorbers by means of sound-absorbing materials

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Duct Arrangements (AREA)
  • Building Environments (AREA)

Abstract

The invention provides a structure for reducing dynamic response of a thin-wall ventilation pipe, which comprises: the ventilation pipe is used for bearing and transmitting the coupled vibration load generated by the high-speed airflow; the skin is used for bearing the vibration load transmitted by the ventilation pipe; the side rib is used for bearing the vibration load transmitted by the ventilation pipe; the partition plate and the ventilation pipe mounting bracket are arranged along the extension direction of the ventilation pipe, and are connected with the skin and the ventilation pipe through rivets so as to bear and transmit the vibration load transmitted by the ventilation pipe; the adjusting gaskets comprise metal sheets with different thicknesses, are connected between the skin and the ventilating pipe and between the skin and the ventilating pipe mounting bracket through rivets and are used for adjusting gaps between the skin and the ventilating pipe and between the skin and the ventilating pipe mounting bracket; and the damping material is bonded with the skin to form a plate-type structure and is used for dissipating the vibration load transmitted by the ventilation pipe.

Description

Structure for reducing dynamic response of thin-wall ventilation pipe
Technical Field
The invention belongs to the technical field of aircraft structure maintenance, and particularly relates to a structure for reducing dynamic response of a ventilation pipe.
Background
The electronic equipment, the fuel oil system, the hydraulic system and other devices or equipment in the aircraft can produce a large amount of heat in the working process, heat dissipation is realized through natural heat dissipation to some heat, and self temperature operation requirement can't be satisfied in the natural dissipation of another part equipment, need introduce the air current from the external world and cool off, and the last draft tube structure of aircraft just introduces the external air current inside the aircraft structure to accelerate the heat dissipation to above-mentioned device or equipment.
In order to meet the weight index of the airplane structure, the ventilating pipe structure usually adopts a thin-wall aluminum alloy structure, but in the large-mach-number flight state of the airplane, the ventilating pipe and high-speed airflow generate coupling vibration, so that the ventilating pipe structure is subjected to fatigue damage, and the heat dissipation of equipment is influenced.
Disclosure of Invention
It is an object of the present invention to provide a structure for reducing the dynamic response of a thin-walled ventilation tube that solves or alleviates at least one of the problems set forth above.
The technical scheme provided by the invention is as follows: a structure for reducing the dynamic response of a thin walled ventilation tube, the structure comprising:
the wall thickness of the ventilation pipe is less than 2mm, and the ventilation pipe is used for bearing and transmitting coupled vibration load generated by high-speed airflow;
the wall thickness of the skin is less than 2mm, and the skin is used for bearing the vibration load transmitted by the ventilation pipe;
the side rib is connected with the skin and the ventilation pipe through rivets and is used for bearing vibration load transmitted by the ventilation pipe;
the partition plate and the ventilation pipe mounting bracket are arranged along the extension direction of the ventilation pipe, and are connected with the skin and the ventilation pipe through rivets so as to bear and transmit the vibration load transmitted by the ventilation pipe;
the adjusting gaskets are connected between the skin and the ventilation pipe and between the skin and the ventilation pipe mounting bracket through rivets and are used for adjusting gaps between the skin and the ventilation pipe and between the skin and the ventilation pipe mounting bracket so as to reduce mounting stress; and
the damping material is larger than the damping coefficient of the skin, and the damping material and the skin are bonded and compounded to form a plate type structure for dissipating the vibration load transmitted by the ventilation pipe.
Further, the thickness of the rib is greater than the thickness of the vent or skin to provide greater structural strength than the vent or skin.
Further, the thickness of the side rib is not less than 3 mm.
Further, the thickness of the partition and the vent mounting bracket does not exceed the thickness of the vent and the skin.
Further, the thickness of the partition plate and the ventilation pipe mounting bracket is below 2 mm.
Furthermore, the damping material comprises a metal layer, damping layers positioned on two sides of the metal layer, a restraining layer positioned on the damping layer on the outer side and a cementing layer positioned on the damping layer on the inner side, and the cementing layer is used for cementing the skin.
Further, the material of the constraint layer is the same as that of the metal layer.
Furthermore, the constraint layer and the metal layer are both made of aluminum alloy materials.
Furthermore, the damping layer is made of rubber.
Further, the thickness of the damping material is not less than 3 mm.
The structure provided by the invention can reduce the coupling vibration response generated by the thin-wall ventilation pipe and high-speed airflow to a great extent, prolong the service life of the ventilation pipe, the ventilation pipe mounting bracket, the skin and other structures, ensure the heat dissipation requirement of the internal equipment of the airplane and avoid secondary disasters.
Drawings
In order to more clearly illustrate the technical solution provided by the present invention, the following briefly introduces the accompanying drawings. It is to be expressly understood that the drawings described below are only illustrative of some embodiments of the invention.
FIG. 1 is a top view of a structure of the present invention for reducing the dynamic response of a thin wall vent.
FIG. 2 is a front view of the structure of the present invention for reducing the dynamic response of a thin wall vent.
FIG. 3 is a top view (without skin) of the structure of the present invention to reduce the dynamic response of a thin wall vent.
FIG. 4 is a side view of a structure of the present invention for reducing the dynamic response of a thin wall vent.
FIG. 5 is a schematic view of the damping material of the present invention.
Reference numerals:
1-covering;
2-side ribs;
3-a separator;
4-a ventilation pipe;
5-adjusting the spacer;
6-a vent pipe mounting bracket;
7-a damping material;
71-a constraining layer;
72-a damping layer;
73-a metal layer;
74-the cement layer.
Detailed Description
In order to make the implementation objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be described in more detail below with reference to the accompanying drawings in the embodiments of the present invention.
As shown in fig. 1 to 4, the structure for reducing the dynamic response of the thin-wall ventilation pipe provided by the invention mainly comprises a skin 1, a side rib 2, a partition plate 3, a ventilation pipe 4, an adjusting gasket 5, a ventilation pipe mounting bracket 6 and a damping material 7.
The skin 1 is an aluminum alloy metal plate, the thickness of the skin is generally below 2mm, the skin has enough strength, and the skin 1 is connected with the side ribs 2, the partition plates 3, the ventilation pipes 4 and the ventilation pipe mounting brackets 6 through rivets and is used for bearing vibration loads transmitted by the ventilation pipes 4;
the side rib 2 is a metal reinforced plate structure formed by machining, the thickness of the side rib 2 is larger than that of the skin 1 or the ventilation pipe 4, generally more than 3mm, and the side rib has enough rigidity and strength, and the side rib 2 is connected with the skin 1 and the ventilation pipe 4 through rivets and is used for bearing the vibration load transmitted by the ventilation pipe 4;
the partition plate 3 is a sheet metal plate, the thickness of the partition plate is generally below 2mm, the partition plate has enough strength, and the partition plate 3 is connected with the skin 1 and the ventilation pipe 4 through rivets and is used for bearing and transmitting the vibration load transmitted by the ventilation pipe 4;
the ventilation pipe 4 is a cylindrical structure formed by welding two sheet metal plates, the thickness of the ventilation pipe is generally below 2mm, the ventilation pipe has enough rigidity and strength, and the ventilation pipe is connected with the skin 1, the side ribs 2, the partition plate 3 and the ventilation pipe mounting bracket 6 through rivets and is used for bearing and transmitting coupling vibration load generated by high-speed airflow;
the adjusting gaskets 5 are a series of metal sheets with different thicknesses, the thicknesses of the adjusting gaskets are between 0.1mm and 1mm, and the adjusting gaskets 5 are connected between the skin 1 and the ventilation pipe 4 and between the skin 1 and the ventilation pipe mounting bracket 6 through rivets and are used for adjusting gaps between the skin 1 and the ventilation pipe 4 and between the skin 1 and the ventilation pipe mounting bracket 6 so as to reduce mounting stress;
the ventilation pipe mounting bracket 6 is a sheet metal plate, the thickness of the ventilation pipe mounting bracket is generally below 2mm, and the ventilation pipe mounting bracket has enough rigidity and strength, and the ventilation pipe mounting bracket 6 is connected with the skin 1 and the ventilation pipe 4 through rivets and is used for bearing and transmitting the vibration load transmitted by the ventilation pipe 4;
the damping material 7 is a composite plate-type structure composed of a metal layer 73, a damping layer 72, a constraint layer 71 and a cementing layer 74, and has a high damping coefficient. The damping layers 72 are arranged on two side faces of the metal layer 73, the constraint layer 71 is arranged outside the upper damping layer 72, the cementing layer 74 is arranged on the lower damping layer 72, the metal layer 73 and the constraint layer 71 are made of aluminum alloy materials, the damping layers 72 are made of rubber, the thickness of the damping layers is generally more than 3mm, and the damping materials 7 are glued on the skin 1 and can be used for dissipating vibration loads transmitted by the ventilation pipe 4.
In the invention, the natural frequency and the dynamic response are calculated by a finite element analysis system, and the damping material 7 capable of being stamped is selected according to the dynamic response result to obtain the layer number of the damping layer 72 and the metal plate thickness parameter of the constraint layer 71, thereby determining the arrangement area of the damping material 7; the side ribs 2, the partition plates 3, the ventilation pipes 4 and the ventilation pipe mounting brackets 6 are connected through rivets, gaps between the skins 1 and the ventilation pipes 4 and gaps between the skins 1 and the ventilation pipe mounting brackets 6 are adjusted through adjusting gaskets 5, and the skins 1 are connected through the rivets, so that no mounting stress is ensured; after all the installation is finished, the overall structure is subjected to modal testing and is contrastively analyzed with a finite element analysis result, the accuracy of each parameter selection of the damping material 7 is determined, the damping material 7 and the skin 1 are connected in a gluing mode, and therefore the vibration load transferred by the ventilation pipe is dissipated, and the purpose of reducing the dynamic response of the ventilation pipe structure is achieved.
The invention provides a method for reducing the suppression of the dynamic response of a ventilation pipe structure. By the method, coupling vibration response generated by the ventilation pipe structure and high-speed airflow can be reduced to a great extent, the service lives of the ventilation pipe structure, the ventilation pipe mounting structure and the skin structure are prolonged, the heat dissipation requirements of internal equipment of the airplane are met, and secondary disasters are avoided.
The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (10)

1. A structure for reducing the dynamic response of a thin walled ventilation tube, the structure comprising:
the wall thickness of the ventilation pipe (4) is less than 2mm, and the ventilation pipe (4) is used for bearing and transmitting coupled vibration load generated by high-speed airflow;
the wall thickness of the skin (1) is less than 2mm, and the skin (1) is used for bearing the vibration load transmitted by the ventilation pipe (4);
the side rib (2) is connected with the skin (1) and the ventilation pipe (4) through rivets and is used for bearing the vibration load transmitted by the ventilation pipe (4);
the partition plate (3) and the ventilation pipe mounting bracket (6) are arranged along the extension direction of the ventilation pipe (4), and the partition plate (3) and the ventilation pipe mounting bracket (6) are connected with the skin (1) and the ventilation pipe (4) through rivets and are used for bearing and transmitting vibration load transmitted by the ventilation pipe (4);
the adjusting gaskets (5) are connected between the skin (1) and the ventilation pipe (4) and between the skin (1) and the ventilation pipe mounting bracket (6) through rivets, and are used for adjusting gaps between the skin (1) and the ventilation pipe (4) and between the skin (1) and the ventilation pipe mounting bracket (6) to reduce mounting stress; and
the damping material (7) has a damping coefficient larger than that of the skin (1), and the damping material (7) and the skin (1) are bonded and compounded to form a plate type structure for dissipating vibration loads transmitted by the ventilation pipe (4).
2. A structure to reduce the dynamic response of thin-walled ventilation ducts according to claim 1, characterized in that the thickness of the edge rib (2) is greater than the thickness of the ventilation duct (4) or the skin (1) to provide greater structural strength than the ventilation duct (4) or the skin (1).
3. A structure to reduce the dynamic response of a thin-walled ventilation tube as claimed in claim 2 wherein the thickness of the ribs (2) is not less than 3 mm.
4. A structure to reduce the dynamic response of thin wall ventilation ducts according to claim 1, characterized in that the thickness of the bulkhead (3) and the duct mounting bracket (6) does not exceed the thickness of the ventilation duct (4) and the skin (1).
5. A structure to reduce the dynamic response of thin walled ventilation tubes as claimed in claim 4 wherein the thickness of the partition (3) and the ventilation tube mounting bracket (6) is below 2 mm.
6. A structure for reducing dynamic response of a thin-walled ventilation tube according to claim 1, wherein the damping material (7) comprises a metal layer (73), damping layers (72) on both sides of the metal layer (73), a constraint layer (71) of the damping layer (72) on the outer side and a cementing layer (74) of the damping layer (72) on the inner side, and the cementing layer (74) is used for cementing with the skin (1).
7. A structure to reduce the dynamic response of a thin-walled ventilation tube as claimed in claim 6 wherein the constraining layer (72) and the metallic layer (73) are of the same material.
8. A structure to reduce the dynamic response of a thin-walled ventilation tube as claimed in claim 7 wherein the constraining layer (72) and the metallic layer (73) are both of aluminum alloy.
9. A structure to reduce the dynamic response of a thin-walled ventilation tube as claimed in claim 6 wherein the damping layer (72) is a rubber material.
10. A structure to reduce the dynamic response of a thin-walled ventilation tube as claimed in any one of claims 6 to 9, wherein the thickness of the damping material (7) is not less than 3 mm.
CN202110905171.9A 2021-08-08 2021-08-08 Structure for reducing dynamic response of thin-wall ventilation pipe Active CN113685614B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110905171.9A CN113685614B (en) 2021-08-08 2021-08-08 Structure for reducing dynamic response of thin-wall ventilation pipe

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Application Number Priority Date Filing Date Title
CN202110905171.9A CN113685614B (en) 2021-08-08 2021-08-08 Structure for reducing dynamic response of thin-wall ventilation pipe

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CN113685614A true CN113685614A (en) 2021-11-23
CN113685614B CN113685614B (en) 2023-01-17

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Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050044712A1 (en) * 2003-08-28 2005-03-03 Gideon David E. Sidewall panel integrated with insulation and air ducts
CN101374721A (en) * 2006-01-17 2009-02-25 空中客车德国有限公司 Structuring construction for an aircraft fuselage
DE102009014377A1 (en) * 2009-03-23 2010-09-30 Airbus Deutschland Gmbh Aircraft structure with air ducts integrated in structural elements
CN205469839U (en) * 2016-01-29 2016-08-17 哈尔滨飞机工业集团有限责任公司 Mounting structure of electronic shutoff valve of aircraft natural draft system
CN106672246A (en) * 2016-12-15 2017-05-17 哈尔滨飞机工业集团有限责任公司 Helicopter power cabin rear sealing structure
CN209700961U (en) * 2018-11-30 2019-11-29 中国航空工业集团公司沈阳飞机设计研究所 A kind of cooling injector of multimedium
CN210564781U (en) * 2019-10-08 2020-05-19 江西洪都航空工业集团有限责任公司 Half-pipe welded type mounting structure of generator ventilation pipe
CN111361743A (en) * 2020-02-21 2020-07-03 中国电子科技集团公司第二十九研究所 Composite material air inlet channel and preparation method thereof
CN212480434U (en) * 2020-05-15 2021-02-05 沈阳兴华航空电器有限责任公司 Ventilation switching device
CN113022858A (en) * 2021-03-04 2021-06-25 中国电子科技集团公司第二十九研究所 Nacelle air inlet and exhaust device

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050044712A1 (en) * 2003-08-28 2005-03-03 Gideon David E. Sidewall panel integrated with insulation and air ducts
CN101374721A (en) * 2006-01-17 2009-02-25 空中客车德国有限公司 Structuring construction for an aircraft fuselage
DE102009014377A1 (en) * 2009-03-23 2010-09-30 Airbus Deutschland Gmbh Aircraft structure with air ducts integrated in structural elements
CN205469839U (en) * 2016-01-29 2016-08-17 哈尔滨飞机工业集团有限责任公司 Mounting structure of electronic shutoff valve of aircraft natural draft system
CN106672246A (en) * 2016-12-15 2017-05-17 哈尔滨飞机工业集团有限责任公司 Helicopter power cabin rear sealing structure
CN209700961U (en) * 2018-11-30 2019-11-29 中国航空工业集团公司沈阳飞机设计研究所 A kind of cooling injector of multimedium
CN210564781U (en) * 2019-10-08 2020-05-19 江西洪都航空工业集团有限责任公司 Half-pipe welded type mounting structure of generator ventilation pipe
CN111361743A (en) * 2020-02-21 2020-07-03 中国电子科技集团公司第二十九研究所 Composite material air inlet channel and preparation method thereof
CN212480434U (en) * 2020-05-15 2021-02-05 沈阳兴华航空电器有限责任公司 Ventilation switching device
CN113022858A (en) * 2021-03-04 2021-06-25 中国电子科技集团公司第二十九研究所 Nacelle air inlet and exhaust device

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