CN111470028B - Self-priming air entraining method for cavity structure noise reduction - Google Patents
Self-priming air entraining method for cavity structure noise reduction Download PDFInfo
- Publication number
- CN111470028B CN111470028B CN202010363702.1A CN202010363702A CN111470028B CN 111470028 B CN111470028 B CN 111470028B CN 202010363702 A CN202010363702 A CN 202010363702A CN 111470028 B CN111470028 B CN 111470028B
- Authority
- CN
- China
- Prior art keywords
- cavity
- air
- cavity structure
- communicated
- self
- 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.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C1/00—Fuselages; Constructional features common to fuselages, wings, stabilising surfaces or the like
- B64C1/40—Sound or heat insulation, e.g. using insulation blankets
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Aviation & Aerospace Engineering (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
- Exhaust Silencers (AREA)
Abstract
The invention belongs to the field of noise control, and discloses a self-priming air entraining method for noise reduction of a cavity structure. The invention can improve the flowing form in the cavity structure and effectively reduce the noise generated by the cavity structure under the action of air flow.
Description
Technical Field
The invention belongs to the field of noise control, and particularly relates to a self-priming air entraining method for cavity structure noise reduction.
Background
The cavity structure is a structural form which is commonly encountered in engineering practice, such as a landing gear cabin, a weapon cabin, an automobile skylight, a high-speed train carriage joint, an automobile door seam and the like of an aircraft, and under certain conditions, fluid flows through the cavity structure, and because of the interaction of the flow of a cavity shear layer and the flow in the cavity, a strong self-sustaining oscillation phenomenon can occur, and strong pressure, speed and other pulsation is generated, and strong noise is radiated outwards. In order to effectively change the flowing state of fluid around the cavity structure and inhibit severe cavity noise, various active and passive control method researches aiming at the cavity structure are developed at home and abroad.
Methods for controlling the flow and noise of the fluid around the cavity structure are mainly divided into active control methods (such as front edge plasma excitation, front edge high-frequency forcing, front edge mass injection, etc.) and passive control methods (such as front edge spoiler, vortex generator, rear edge slope, etc.). However, the existing active control method often needs additional mechanical actuating mechanisms, external excitation voltage increase, air entraining systems and the like, so that the structure nearby the cavity structure is more complex, and the self weight of the cavity structure is increased; the existing passive control method is difficult to obtain practical engineering application because a turbulence structure is added at the front edge of the cavity, so that the aerodynamic performance of the cavity structure can be changed.
Disclosure of Invention
The purpose of the invention is that: in order to suppress the problem of intense noise and unstable fluid flow generated by the cavity structure under the action of fluid. The invention provides a flow and noise control method for a cavity structure, which has simple configuration and good noise reduction effect.
The technical scheme provided by the invention is as follows: there is provided a self-priming bleed air method for noise reduction of a cavity structure comprising a leading edge, a cavity open on one side and a trailing edge, the cavity comprising a front wall, a floor and a rear wall, the method comprising that any two of the leading edge, the front wall and the rear wall are in communication via at least one connecting channel.
Further, the connecting channel is an air-entraining pipe, and the front edge is provided with an air-entraining hole; one end of the air guiding pipe is communicated with the air guiding hole, and the other end of the air guiding pipe penetrates through the front wall of the cavity to be communicated with the cavity.
Further, the connecting channel is an air-entraining pipe, and the front edge is provided with an air-entraining hole; one end of the air guiding pipe is communicated with the air guiding hole, and the other end of the air guiding pipe penetrates through the rear wall of the cavity to be communicated with the cavity.
Further, the connecting channel is an air guide pipe, one end of the air guide pipe penetrates through the front wall of the cavity to be communicated with the cavity, and the other end of the air guide pipe penetrates through the rear wall of the cavity to be communicated with the cavity.
Further, the air-inducing pipe is a tubular air-inducing pipe.
Further, the cross section of the bleed air pipe in the vertical length direction is rectangular.
Further, the cross section of the bleed air pipe in the vertical length direction can be of other shapes.
Further, a groove body is formed in the side face, close to the front edge, of the front wall; one end of the groove body is communicated with the front edge, and the other end of the groove body is communicated with the cavity.
Further, the groove body of the front wall is internally embedded with an air entraining pipe; one end of the air guiding pipe is communicated with the front edge, and the other end is communicated with the cavity.
The invention has the technical effects that: under the prior art condition and test condition, the method with simple structure can play a good role in controlling fluid flow and inhibiting cavity noise. The method does not need to introduce a complex mechanical structure, and has less influence on the aerodynamic performance and structural form of the cavity structure. In practical application, the connection position of the air guide pipe and the geometric parameters of the air guide pipe are determined according to the flow rate of the fluid flowing through the cavity structure and the geometric parameters of the cavity structure.
According to the invention, the pressure difference between different areas of the cavity structure is utilized to enable air flow and sound waves to automatically circulate in the air-entraining pipe, so that the pressure distribution in the cavity structure is balanced, the oscillating circuit in the cavity structure is changed, the intensity of a strong sound standing wave mode in the cavity structure is restrained, and in addition, jet flow formed by leading the air flow to a low-pressure area of the cavity structure also changes the flow state in the cavity of the cavity structure; the flow form in the cavity structure can be improved, and the noise generated by the cavity structure under the action of air flow is effectively reduced.
The method has the advantages of simple structure, good reliability, strong replaceability and the like. The applicability is better, the popularization and the application are easy, and the engineering application and military value are higher.
Drawings
FIG. 1 is a schematic view of a structure in which a front edge of a cavity structure communicates with a front wall of a cavity;
FIG. 2 is a schematic view of the structure in which the front edge of the cavity structure communicates with the rear wall of the cavity;
FIG. 3 is a schematic view of the structure in which the front wall of the cavity communicates with the rear wall of the cavity;
FIG. 4 is a schematic view of a circular tube type bleed air tube structure;
FIG. 5 is a schematic view of a rectangular bleed air duct;
fig. 6 is a schematic diagram of the working principle of the present invention.
Detailed Description
The invention is characterized in that: the cavity structure is subject to the action of external high velocity fluid, and fluid flow within the cavity structure cavity can become extremely complex, accompanied by intense cavity noise. The self-priming air entraining method provided by the invention is used for changing the fluid flow state in the cavity of the cavity structure and inhibiting the cavity noise of the cavity structure. According to the method, different areas of the cavity structure are communicated through the air-inducing pipe, fluid in the cavity circulates in the air-inducing pipe by utilizing fluid pressure difference among the different areas of the cavity structure, the communication of the different pressure areas can balance pressure distribution in the cavity structure, the introduction of the air-inducing pipe can change an oscillating loop of fluid movement in the cavity of the cavity structure, and the intensity of a strong sound standing wave mode in the cavity structure is restrained. In addition, the introduction of fluid from the high-pressure region of the cavity structure to the low-pressure region forms a jet at the bleed air duct outlet, which jet changes the flow state of the fluid in the low-pressure region of the jet outlet. Wherein the fluid flow direction flows from the leading edge to the trailing edge of the cavity structure, the fluid pressure at the cavity back wall being greater than the pressure at the cavity front wall. Therefore, the invention can effectively change the fluid flow form of the cavity structure under the action of high-speed fluid and inhibit cavity noise.
The air duct provided by the invention does not refer to a tubular duct, is defined in a broad sense, and comprises a tubular structure externally arranged on the periphery of a cavity structure or other shape structures, and also comprises an air ventilation structure reserved in the cavity structure design of the cavity structure.
Example 1
Specifically, in this embodiment, a self-priming air entraining method for noise reduction of a cavity structure is provided, as shown in fig. 1, 2 and 3, fig. 1 is a schematic structural diagram of communication between a cavity structure front edge and a cavity front wall, fig. 2 is a schematic structural diagram of communication between a cavity structure front edge and a cavity rear wall, fig. 3 is a schematic structural diagram of communication between a cavity front wall and a cavity rear wall, the cavity structure 1 includes a front edge 10, a cavity 30 with an opening on one side, and a rear edge 20, and the cavity 30 includes a front wall 31, a bottom plate, and a rear wall 32. Fig. 6 is a schematic diagram of the working principle of the self-priming bleed method for cavity structure noise reduction (illustrated by the front edge communicating with the rear wall).
Fig. 1 is a diagram showing one of the preferred embodiments of the present embodiment. In this embodiment, the front edge 10 of the cavity structure is provided with an exhaust hole; one end of the air-introducing pipe 11 is communicated with the air vent, and the other end passes through the front wall 31 of the cavity to be communicated with the cavity 30. According to the embodiment, the front edge of the cavity structure is communicated with the front wall of the cavity, so that interaction between fluid flowing through the front edge of the cavity and fluid flowing through the front middle part of the cavity is realized, the flowing form in the cavity is changed, the pressure difference between the inside and the outside of the cavity is balanced, and the noise level of the front middle part of the cavity is effectively reduced.
Fig. 2 is a schematic diagram of another preferred implementation of the present embodiment. In this embodiment, the front edge 10 of the cavity structure is provided with an exhaust hole; one end of the air bleed tube 12 communicates with the vent and the other end communicates with the cavity 30 through the rear wall 32 of the cavity. Referring to fig. 2 and 6, the fluid flow direction is shown by an arrow in the drawing, and in this embodiment, by conducting the front edge of the cavity structure with the rear wall of the cavity, the interaction between the fluid flowing through the front edge of the cavity and the fluid flowing through the rear part in the cavity is realized, so that the intensity of the strong acoustic standing wave mode in the cavity of the cavity structure can be effectively inhibited, the oscillation loop in the cavity is changed, and the pressure distribution in the cavity is balanced; in addition, the fluid is led to the front edge of the cavity structure to influence external flow, jet flow is formed, the height of the front edge out of the fluid is raised, the impact action of the fluid on the rear wall of the cavity is weakened, and the noise level of the rear area of the cavity structure is weakened.
Fig. 3 is a schematic diagram of another preferred implementation of the present embodiment. In this embodiment, the air duct 13 communicates at one end with the cavity 30 through the front wall 31 of the cavity and at the other end with the cavity 30 through the rear wall 32 of the cavity. According to the embodiment, through conducting the front wall of the cavity body and the rear wall of the cavity body, the interaction between the fluid in the front middle part of the cavity body and the fluid in the rear part of the cavity body is realized, the fluid with larger pulsating pressure at the rear wall of the cavity body can realize the interaction between the front fluid and the rear fluid through the air guide pipe, the single mode that the original fluid in the cavity body reversely flows back to the front middle part from the rear wall is changed, the guided air flow forms jet flow at the front wall, the noise level of the front middle part of the cavity body is slightly improved, the noise level of the rear part of the cavity body is obviously reduced, and the noise reduction effect is obvious.
When the method provided by the invention is actually used, different connecting modes are required to be selected according to the relation between the flow velocity of fluid flowing through the cavity structure and the geometric dimension of the cavity structure so as to achieve the effects of fluid flow control and noise suppression.
Further, the air duct of the present embodiment has a tubular structure, as shown in fig. 4, and fig. 4 is a schematic structural view of a circular tube type air duct. Alternatively, the cross section of the air duct in the vertical length direction of the embodiment is rectangular, specifically rectangular, as shown in fig. 5, and fig. 5 is a schematic structural view of the rectangular air duct. Of course, the shape of the air intake pipe is not limited in the present invention, and the cross section in the vertical length direction may be other shapes.
The method of the invention covers any shape, form of bleed air duct structure. In practical use of the method provided by the invention, the form and shape of the air guide pipe are comprehensively selected according to the flow rate of fluid flowing through the cavity structure, the geometric dimension of the cavity structure, the shape of the cavity structure and other factors.
Example 2
In this embodiment, another self-priming bleed method for noise reduction of an embedded missile trunk is provided. Referring to fig. 1, a groove is formed in the side surface of the front wall 31 of the cavity 30 near the front edge; one end of the groove body is communicated with the front edge 10, and the other end of the groove body is communicated with the cavity; in this embodiment, no bleed is used. Of course, an air introducing pipe can be embedded in the groove body of the front wall; one end of the air guiding pipe is communicated with the front edge, and the other end is communicated with the cavity.
Claims (7)
1. A self-priming air entraining method for noise reduction of a cavity structure, wherein the cavity structure comprises a front edge, a cavity with an opening at one side and a rear edge, the cavity comprises a front wall, a bottom plate and a rear wall, and air flows from the front edge to the rear edge of the cavity structure from one side of the opening of the cavity, and the self-priming air entraining method is characterized in that any two of the front edge, the front wall and the rear wall are communicated through at least one connecting channel;
wherein the connecting channel is an air suction pipe; the connection position of the air-entraining pipe and the geometric parameters of the air-entraining pipe are determined according to the flow velocity of the fluid flowing through the cavity structure and the geometric parameters of the cavity structure.
2. The self-priming method of claim 1, wherein the leading edge is vented; one end of the air guide pipe is communicated with the air exhaust hole, and the other end of the air guide pipe penetrates through the front wall of the cavity to be communicated with the cavity.
3. The self-priming method of claim 1, wherein the leading edge is vented; one end of the air guide pipe is communicated with the air exhaust hole, and the other end of the air guide pipe penetrates through the rear wall of the cavity to be communicated with the cavity.
4. The self-priming method of claim 1, wherein one end of the bleed duct communicates with the cavity through a front wall of the cavity and the other end communicates with the cavity through a rear wall of the cavity.
5. Self-priming method according to any one of claims 2 to 4, characterized in that the bleed duct is a tubular bleed duct.
6. The self-priming bleed air method as claimed in any of claims 2 to 4, characterized in that the bleed air duct has a rectangular cross section in the vertical length direction.
7. A self-priming air entraining method for noise reduction of a cavity structure, wherein the cavity structure comprises a front edge, a cavity with an opening at one side and a rear edge, the cavity comprises a front wall, a bottom plate and a rear wall, and air flows from the front edge to the rear edge of the cavity structure from one side of the opening of the cavity, and the self-priming air entraining method is characterized in that any two of the front edge, the front wall and the rear wall are communicated through at least one connecting channel;
wherein, a groove body is arranged on the side surface of the front wall, which is close to the front edge; one end of the groove body is communicated with the front edge, and the other end of the groove body is communicated with the cavity; the air-entraining pipe is embedded in the groove body of the front wall; one end of the air guiding pipe is communicated with the front edge, and the other end is communicated with the cavity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010363702.1A CN111470028B (en) | 2020-04-30 | 2020-04-30 | Self-priming air entraining method for cavity structure noise reduction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010363702.1A CN111470028B (en) | 2020-04-30 | 2020-04-30 | Self-priming air entraining method for cavity structure noise reduction |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111470028A CN111470028A (en) | 2020-07-31 |
| CN111470028B true CN111470028B (en) | 2023-06-23 |
Family
ID=71764333
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010363702.1A Active CN111470028B (en) | 2020-04-30 | 2020-04-30 | Self-priming air entraining method for cavity structure noise reduction |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111470028B (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8632031B2 (en) * | 2011-04-11 | 2014-01-21 | The Boeing Company | Systems and methods for attenuation of noise and wakes produced by aircraft |
| US10532805B2 (en) * | 2016-09-20 | 2020-01-14 | Gulfstream Aerospace Corporation | Airfoil for an aircraft having reduced noise generation |
| CN206031794U (en) * | 2016-09-27 | 2017-03-22 | 中国空气动力研究与发展中心高速空气动力研究所 | Weapon -bay noise suppression device based on environment gas jet |
| CN106741922A (en) * | 2017-01-24 | 2017-05-31 | 厦门大学 | A kind of rotor noise suppressing method based on swept tip perforate |
| CN108482641B (en) * | 2018-03-22 | 2020-06-30 | 中国空气动力研究与发展中心高速空气动力研究所 | Damping layer and rear wall pressure relief pipe combined structure for reducing pneumatic noise of embedded cabin |
-
2020
- 2020-04-30 CN CN202010363702.1A patent/CN111470028B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN111470028A (en) | 2020-07-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111929026B (en) | Low-frequency pressure pulsation suppression method for wind tunnel 3/4 opening test section | |
| CA2643071A1 (en) | Aerodynamic flap of an aircraft with a device which influences the flap turbulence | |
| CN104280205A (en) | Supersonic velocity laminar flow spraying pipe and supersonic velocity quiet wind tunnel thereof | |
| CN111516891B (en) | Exciter capable of simultaneously realizing steady air suction and oscillation air blowing | |
| CN104481700A (en) | Combined dynamic axisymmetric variable geometry inlet, engine and air inlet control method | |
| CN111470028B (en) | Self-priming air entraining method for cavity structure noise reduction | |
| CN111564149A (en) | Cavity structure noise control method and device based on controllable impedance boundary | |
| JP4873505B2 (en) | Low noise aircraft | |
| CN106014684A (en) | Combined flow control method and structure for improving SERN for TBCC | |
| CN111470045B (en) | Self-suction air entraining device for embedded weapon cabin of aircraft | |
| CN103101625B (en) | Noise suppression device of high frequency pulse jet weapon cabin | |
| CN108482641B (en) | Damping layer and rear wall pressure relief pipe combined structure for reducing pneumatic noise of embedded cabin | |
| CN208040787U (en) | Injector | |
| CN117566072A (en) | Gas drainage active cavitation device suitable for bionic ray underwater vehicle | |
| CN106014683A (en) | Pressurization flow control device-containing SERN structure for TBCC | |
| CN211308562U (en) | High-speed train damping device based on low-density gas injection | |
| CN111959674A (en) | Strong mobility supercavitation navigation device based on straight rudder preposed hydrodynamic layout | |
| CN114295016B (en) | Underwater supercavitation navigation body configuration based on combination of multistage cavitation and wake entrainment | |
| CN110886653B (en) | Jet engine shock wave protection system | |
| CN216185999U (en) | Aircraft wing flap | |
| CN118128641B (en) | Wide-speed-range air inlet channel control device, control method and aircraft air inlet system | |
| CN112173082A (en) | Micro-vortex generating device with auxiliary control of airflow | |
| CN113879512A (en) | Course synergistic system and wing body fusion layout aircraft with same | |
| JP3744145B2 (en) | Oil pump device | |
| KR20020077112A (en) | Method and device for diminish in drag by turbulent flow control of hull surface of ship |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |