CN115030837B

CN115030837B - Spout noise reduction device

Info

Publication number: CN115030837B
Application number: CN202210956872.XA
Authority: CN
Inventors: 仝帆; 崔盼望; 章荣平; 陈正武; 李抢斌; 覃晨; 王勇; 张俊龙
Original assignee: Low Speed Aerodynamics Institute of China Aerodynamics Research and Development Center
Current assignee: Low Speed Aerodynamics Institute of China Aerodynamics Research and Development Center
Priority date: 2022-08-10
Filing date: 2022-08-10
Publication date: 2022-11-08
Anticipated expiration: 2042-08-10
Also published as: CN115030837A

Abstract

The invention discloses a nozzle noise reduction device which comprises a culvert cylinder and turbulence members, wherein the turbulence members are arranged at a nozzle of the culvert cylinder, the turbulence members are arranged on the inner circumferential wall of the culvert cylinder, and are distributed along the circumferential direction of the culvert cylinder; in the above scheme, the bulge of vortex piece changes the flow of high-speed air current in nozzle department, makes the vortex structure change to eliminate the sound of whistling of supersonic velocity efflux, meanwhile, the bulge can also increase the mixing of inner culvert barrel efflux and outside air, is favorable to falling the noise of various noise compositions.

Description

Spout noise reduction device

Technical Field

The invention relates to the technical field of aero-engines, in particular to a nozzle noise reduction device.

Background

Jet noise is a common noise pollution, widely existing in life of people, such as aircraft engines, fighters, rocket launching and the like in aviation, and is one of jet noise pollution sources, and has great influence on surrounding residents and environment. The jet noise reduction is reduced, and the aerodynamic performance of the jet noise reduction is not changed as much as possible, so that the jet noise reduction design is a basis for developing a series of jet noise reduction designs. In the related art, many researchers have conducted analytical research on jet noise reduction, for example, jet noise can be effectively suppressed by changing the shape of the trailing edge of the nozzle and the type of the nozzle, so as to change the length of the core region and the size of the dimension of the turbulent structure.

At present, the common jet noise reduction mode is to change the external shape of a nozzle, for example, the tail edge of the nozzle is processed into a sawtooth shape, and jet noise is controlled by changing different parameters such as the number of sawteeth, the cutting degree, the length of the sawteeth and the like, and researches show that the sawtooth-shaped nozzle reduces the jet noise of a low frequency band and increases the jet noise of a high frequency band; the noise reduction amount of a low frequency band can be increased by increasing the cut-in angle of the zigzag nozzle, and the noise reduction amount is 5dB at most; in addition, the change of the tooth number of the zigzag nozzle has certain influence on the noise reduction effect, but the influence is far smaller than the influence of the cut-in angle on the noise reduction effect.

Experiments show that although jet flow noise can be reduced by the zigzag or wavy nozzles, the pneumatic performance of the spray pipe is adversely affected, and the pneumatic performance of the spray pipe is reduced; meanwhile, a large number of models need to be processed for testing when the optimal zigzag nozzle is found, the nozzle is greatly changed, the cost is high, and the operation is difficult.

Therefore, the technical problem to be solved urgently by the technical personnel in the field is to provide a noise reduction measure which is reliable, effective, low in cost, small in change of the spray pipe, simple and easy to implement, and does not reduce the aerodynamic performance of the spray nozzle.

Disclosure of Invention

The invention discloses a nozzle noise reduction device, which aims to solve the technical problems of large nozzle change, nozzle aerodynamic performance reduction and the like in noise reduction measures in the related art.

In order to solve the problems, the invention adopts the following technical scheme:

the invention discloses a nozzle noise reduction device, which comprises a culvert cylinder and a spoiler; wherein:

the turbulence pieces are arranged on the inner circumferential wall of the containing cylinder body, and the plurality of turbulence pieces are distributed along the circumferential direction of the containing cylinder body;

the spoiler have protrusion in the bulge of the internal perisporium of the culvert barrel, on the first direction, the bulge has first inclined plane and second inclined plane, first inclined plane with the second inclined plane intersect in the top of bulge, just the first length on first inclined plane is greater than the second length on second inclined plane, the first direction is the jet direction of efflux in the culvert barrel.

Furthermore, the height from the top of the bulge to the inner peripheral wall of the culvert cylinder is 2mm to 6mm.

Further, the spoiler with the connotative cylinder body integrated into one piece.

Further, the spoiler with the connotative cylinder body can be dismantled and be connected.

Further, the vortex piece still includes the installation department, the connotative barrel be provided with installation department assorted mounting groove, the installation department is located in the mounting groove.

Further, in the first direction, the cross-sectional shape of the mounting portion is T-shaped or wedge-shaped.

Further, the installation department includes anticreep section and changeover portion, the bulge with the changeover portion links to each other, just the bulge protrusion in the surface of changeover portion, on the second direction, the projection area of changeover portion is located in the projection area of anticreep section, the second direction does the radial direction of connotation barrel.

Further, anticreep section, changeover portion and the bulge integrated into one piece.

Furthermore, a flange plate is arranged at the outlet of the nozzle of the culvert cylinder, and the flange plate is in limit fit with the spoiler in the jet direction of jet flow in the culvert cylinder.

The technical scheme adopted by the invention can achieve the following beneficial effects:

the nozzle noise reduction device has the advantages that the noise reduction mechanism of the supersonic jet noise is that the protruding part of the spoiler can change unstable waves and shock wave system structures near the nozzle, and the mode generation and transformation of the howling of the supersonic nozzle are changed, so that the howling of the supersonic jet is eliminated; meanwhile, the protruding part can increase the mixing of supersonic jet flow and outside air to a certain extent, which is beneficial to the noise reduction of various noise components;

secondly, the nozzle of the culvert cylinder is provided with the turbulence piece, and the device has the advantages of simple structure, convenience in installation, reliable noise reduction effect, small influence on the pneumatic performance of the nozzle and the like.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is one of schematic structural diagrams of a jet noise reduction device according to an embodiment of the present application;

FIG. 2 is a second schematic structural diagram of a jet noise reduction device according to an embodiment of the present application;

FIG. 3 is a schematic view of an installation of a spoiler of an embodiment of the present application;

FIG. 4 is one of the structural schematic diagrams of a spoiler of an embodiment of the present application;

FIG. 5 is a second schematic structural view of a spoiler in accordance with an embodiment of the present application;

FIG. 6 is a schematic structural diagram of a test system according to an embodiment of the present application;

FIG. 7 is one of the noise spectrum results plots for monitoring point Mic 7;

FIG. 8 is a second plot of the noise spectrum results for monitor point Mic 7;

FIG. 9 is a third graph of the noise spectrum results for monitoring point Mic 7;

FIG. 10 is a fourth plot of the noise spectrum results for monitor point Mic 7;

FIG. 11 is a fifth plot of the noise spectrum results for monitor point Mic 7;

FIG. 12 is a sixth plot of the noise spectrum results for monitor point Mic 7;

FIG. 13 is a seventh plot of the noise spectrum results for monitor point Mic 7;

FIG. 14 is a plot of the noise total sound pressure level directivity for the jet noise reducer and the reference jet at subsonic velocity;

FIG. 15 is a directivity diagram of the total sound pressure level of noise between the jet noise reducer and the reference jet at supersonic speed;

FIG. 16 is a schematic view of flow lines near the jets of the jet noise reducer of the embodiment of the present application;

FIG. 17 is an enlarged partial schematic view at A of FIG. 16;

FIG. 18 is a schematic view of streamlines near a reference jet;

fig. 19 is a partially enlarged schematic view at B in fig. 18;

FIG. 20 is a schematic diagram showing the distribution of the flow direction vorticity of the jet noise reducing device and the reference jet near the jet along the circumferential direction;

fig. 21 is a schematic diagram of the distribution of turbulent kinetic energy of the jet noise reducing device and the reference jet near the jet along the circumferential direction.

In the figure:

100-a culvert cylinder body, 110-a mounting groove and 120-a flange plate; 200-a spoiler, 210-a bulge, 211-a first inclined plane, 212-a second inclined plane, 220-a mounting part, 221-an anti-falling section and 222-a transition section; 300-a full anechoic chamber; 400-microphone.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

The terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be appreciated that the data so used may be interchanged under appropriate circumstances such that embodiments of the application may be practiced in sequences other than those illustrated or described herein, and that the terms "first," "second," and the like are generally used herein in a generic sense and do not limit the number of terms, e.g., the first term can be one or more than one. In addition, "and/or" in the specification and claims means at least one of connected objects, a character "/", and generally means that the former and latter related objects are in an "or" relationship.

The following describes in detail the jet noise reduction device provided in the embodiment of the present application with reference to fig. 1 to 21 through specific embodiments and application scenarios thereof.

Referring to fig. 1 to 21, the embodiment of the application discloses a nozzle noise reduction device, which comprises a culvert cylinder 100 and a spoiler 200.

Wherein, the connotative cylinder 100 has the spout, and vortex piece 200 locates in the connotative cylinder 100 and near the spout, and the internal perisporium of the connotative cylinder 100 is located to a plurality of vortex pieces 200, and a plurality of vortex pieces 200 distribute along the circumference of the connotative cylinder 100, and vortex piece 200 both can be evenly arranged in the circumferencial direction of the connotative cylinder 100, also can non-uniformly arrange, and this application is not injectd.

In the embodiment of the present application, the spoiler 200 is a plate-shaped member, and the spoiler 200 is arranged to extend in a first direction, which is an injection direction of the jet flow in the intension cylinder 100. The spoiler 200 has a protrusion 210 protruding from the inner circumferential wall of the culvert cylinder 100, and in a first direction, the protrusion 210 has a first inclined surface 211 and a second inclined surface 212, and both the first inclined surface 211 and the second inclined surface 212 are inclined with respect to the first direction.

The first inclined surface 211 and the second inclined surface 212 intersect at the top of the protrusion 210, that is, the first inclined surface 211 is the upstream surface of the protrusion 210, and the second inclined surface 212 is the downstream surface of the protrusion. In the first direction, the first inclined plane 211 has a first length L1, the second inclined plane 212 has a second length L2, and L1 is greater than L2, that is, the inclination angle of the first inclined plane 211 with respect to the first direction is smaller than the inclination angle of the second inclined plane 212 with respect to the first direction.

The nozzle noise reduction device disclosed in the embodiment of the application has the noise reduction mechanism for supersonic jet noise that the protruding part 210 of the spoiler 200 can change the flow of high-speed airflow in the inner culvert cylinder 100, change the unstable wave and shock wave system structure near the nozzle, and change the vortex structure, so that the mode generation and transformation of the howling of the supersonic nozzle are changed, and the purpose of eliminating the howling of the supersonic jet is achieved; meanwhile, the protruding portion 210 may also increase the mixing of the supersonic jet and the outside air to a certain extent, which is beneficial to the noise reduction of various noise components.

As can be seen from the above description, the first inclined surface 211 and the second inclined surface 212 intersect at the top of the bulge 210, in the embodiment of the present application, the height from the top of the bulge 210 to the inner circumferential wall of the culvert cylinder 100 is 2mm to 6mm, for example, the height from the top of the bulge 210 to the inner circumferential wall of the culvert cylinder 100 may be 2mm, 4mm, or 6mm.

In a further technical scheme, spoiler 200 still includes installation department 220, and connotative barrel 100 is provided with and installs installation slot 110 of 220 assorted with installation department, and installation department 220 locates in the installation slot 110.

In the present embodiment, the cross-sectional shape of the mounting portion 220 is T-shaped or wedge-shaped in the first direction; under this condition, mounting groove 110 and installation department 220 phase-match, in the radial direction of the culvert barrel 100, the cell wall of mounting groove 110 can play limiting displacement to installation department 220, avoids spoiler 200 to rock or break away from in the footpath of culvert barrel 100.

In an alternative embodiment, the mounting portion 220 includes an anti-separation section 221 and a transition section 222, when the spoiler 200 is assembled to the culvert cylinder 100, the anti-separation section 221 is located in the mounting groove 110, an inner surface of the transition section 222 is flush with an inner peripheral wall of the culvert cylinder 100, the protrusion 210 is connected to the transition section 222, and the protrusion 210 protrudes from the inner surface of the transition section 222. In a second direction, the projection area of the transition section 222 is located within the projection area of the anti-dropping section 221, and the second direction is the radial direction of the connotation cylinder 100; under such an arrangement, referring to fig. 4 and 5, the cross section of the mounting portion 220 is T-shaped, a step surface is formed between the anti-falling section 221 and the transition section 222, and the step surface is in limit fit with the inner wall of the mounting groove 110 in the second direction, so as to prevent the spoiler 200 from shaking or falling off.

In the embodiment of the present application, the anti-dropping section 221, the transition section 222 and the protruding portion 210 may be an integrally formed part, and the integrally formed part has the characteristics of convenient processing and high structural stability.

In an alternative embodiment, the spoiler 200 may be detachably connected to the culvert cylinder 100, specifically, a flange 120 is provided at the outlet of the nozzle of the culvert cylinder 100, and the flange 120 is in limit fit with the spoiler 200 in the jet direction of the jet flow in the culvert cylinder 100; in this case, when the spoiler 200 is installed, the spoiler 200 may be slid into the installation groove 110 from the nozzle end, and then the flange 120 is connected to the nozzle end, so that the flange 120 and the spoiler 200 are in spacing fit in the injection direction of the jet flow in the culvert cylinder 100, thereby preventing the spoiler 200 from being separated from the axial direction of the culvert cylinder 100.

In another alternative embodiment, the spoiler 200 may be further formed integrally with the culvert cylinder 100, in this way, the nozzle noise reduction device of the embodiment of the present application has high structural stability.

To the nozzle noise reduction device of the embodiment of the present application, the embodiment adopts a test system to perform testing and analysis, the test system includes a full anechoic chamber 300 and a microphone 400 disposed in the full anechoic chamber 300, and the specific process includes:

testing a pre-prepared model test piece under different testing working conditions to obtain noise test data;

and analyzing to obtain the noise reduction effect and the noise suppression capability of the model test piece under different test working conditions based on the noise test data.

In the embodiment of the present application, referring to fig. 6 to 21, an experimental group and a comparison group are provided to explain a noise reduction effect of the nozzle noise reduction device in the embodiment of the present application. Specifically, the control group was a reference nozzle on which the spoiler 200 was not provided, the diameter D =56mm of the reference nozzle; the spoiler 200 is added to the experimental group on the basis of the reference nozzle, wherein the thickness B =2mm of the protrusion 210, the height H =2mm from the top of the protrusion 210 to the inner circumferential wall of the containing cylinder 100, the first length L1=10mm of the first inclined surface 211, the second length L2=5mm of the second inclined surface 212, and the distance L3=5mm from the nozzle outlet of the protrusion 210. A46 AE type microphone of G.R.A.S company is selected in the experiment, the sampling frequency of the microphone set in the experiment is 51.2KHz, and 20s of noise data are collected in each working condition.

In the embodiment, a total of 7 groups of different mach numbers, namely mach numbers Ma =0.9, 1.0, 1.1, 1.2, 1.3, 1.4 and 1.5, are set to simulate different test working conditions so as to consider the noise reduction effect variation and noise suppression capability of the radially convex bulge under different working conditions. In this embodiment, noise reduction spectrograms under different mach numbers measured by the monitoring point Mic7 shown in fig. 7 to 13 are obtained by analyzing the noise signal and the performance collected by the microphone.

The noise spectrum obtained by the test of the invention is analyzed, and the change rules of single-tone noise and integral broadband noise in the spectrogram are explored. As can be seen from the frequency spectrograms of fig. 7 to 13, the convex portion of the radial protrusion has a good noise reduction effect in a range from the subsonic velocity to the supersonic velocity, especially in the supersonic velocity range. When the Mach numbers Ma =0.9 and Ma =1.0, the noise reduction effect on broadband noise below 1000Hz is obvious; in the supersonic speed range, the single-tone noise and the broadband noise can be reduced remarkably, for example, when Ma =1.2, the peak value of the single-tone noise can be reduced by about 30dB, the broadband noise can be reduced by about 10dB, and the obvious noise reduction effect is also shown at other supersonic speed mach numbers.

Referring to fig. 14, under the subsonic working condition, compared with the reference nozzle, the nozzle noise reduction device in the embodiment of the present application has a certain noise reduction effect on the total sound pressure level of jet flow noise, and reduces the total sound pressure level noise by about 2dB; referring to fig. 15, under the supersonic operating condition, compared with the reference nozzle, the nozzle noise reduction device according to the embodiment of the present application has a more significant noise reduction effect on the total sound pressure level of the jet flow noise, and reduces the total sound pressure level noise by about 10dB.

Referring to fig. 16 to 19, it is apparent that, compared to a reference nozzle, in the nozzle noise reduction device according to the embodiment of the present application, in the jet direction of the jet flow, the spoiler 200 induces the flow field to generate a pair of vortexes with opposite rotation directions, which may increase the mixing of nearby fluids, and is beneficial to noise reduction.

Referring to fig. 20, which shows a schematic diagram of the distribution of the flow direction vorticity of the jet noise reduction device and the reference jet near the jet along the circumferential direction, it can be seen that, after the spoiler 200 is added, each spoiler 200 generates the pair of vortex flows with opposite rotation directions, which can increase the mixing of the fluid near the jet.

Referring to fig. 21, which shows a schematic diagram of the distribution of the turbulent kinetic energy of the jet noise reduction device and the reference jet near the jet in the circumferential direction according to the embodiment of the present application, it is apparent from the figure that the spoiler 200 can significantly increase the turbulent kinetic energy downstream of the spoiler, and promote the mixing of the fluid, which helps to reduce the noise.

It should be noted that the nozzle noise reduction device in the embodiment of the present application may be a product actually applied to an aircraft engine, or may be an experimental model for experimental research, and the spoiler 200 is respectively limited in the radial direction and the axial direction of the inclusion cylinder 100, so as to realize the relative fixation of the spoiler 200 and the inclusion cylinder 100. When the spout noise reduction device is used as an experimental model, the spoiler 200 can be detachably connected with the containing cylinder 100, so that the model test piece can be conveniently replaced, for example, the spoiler 200 with different heights H can be replaced for testing, and the testing cost can be greatly saved; in practical applications in aircraft engines, the spoiler 200 is preferably integrally formed with the containing cylinder 100.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising a component of' 8230; \8230;" does not exclude the presence of another like element in a process, method, article, or apparatus that comprises the element. Further, it should be noted that the scope of the methods and apparatuses in the embodiments of the present application is not limited to performing the functions in the order illustrated or discussed, but may include performing the functions in a substantially simultaneous manner or in a reverse order based on the functions recited, e.g., the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and shall cover the scope of the present invention.

Claims

1. The jet noise reduction device is characterized by comprising a containing cylinder body (100) and a flow disturbing piece (200); wherein:

the flow disturbing pieces (200) are arranged on the inner peripheral wall of the containing cylinder body (100), and the flow disturbing pieces (200) are distributed along the circumferential direction of the containing cylinder body (100);

the spoiler (200) has protrusion (210) of protrusion in the internal perisporium of intension barrel (100), and on the first direction, protrusion (210) have first inclined plane (211) and second inclined plane (212), first inclined plane (211) with second inclined plane (212) intersect in the top of protrusion (210), just the first length on first inclined plane (211) is greater than the second length on second inclined plane (212), first direction is the jet direction of efflux in intension barrel (100).

2. A spout noise reduction device according to claim 1, wherein the height of the top of the protrusion (210) from the inner circumferential wall of the culvert cylinder (100) is 2mm to 6mm.

3. A jet noise reduction device according to claim 1, characterized in that the spoiler (200) is integrally formed with the culvert cylinder (100).

4. A jet noise reduction device according to claim 1, characterized in that the spoiler (200) is detachably connected with the culvert cylinder (100).

5. A nozzle noise reduction device according to claim 4, wherein the spoiler (200) further comprises an installation part (220), the containing cylinder (100) is provided with an installation groove (110) matched with the installation part (220), and the installation part (220) is arranged in the installation groove (110).

6. A jet noise reducing arrangement according to claim 5, wherein the mounting portion (220) is T-shaped or wedge-shaped in cross-section in the first direction.

7. A spout noise reduction device according to claim 5, wherein the mounting portion (220) comprises a retaining section (221) and a transition section (222), the protrusion (210) is connected with the transition section (222), the protrusion (210) protrudes from the inner surface of the transition section (222), and in a second direction, the projection area of the transition section (222) is located within the projection area of the retaining section (221), and the second direction is the radial direction of the culvert cylinder (100).

8. A spout noise reduction device according to claim 7, wherein the retaining section (221), transition section (222) and protrusion (210) are integrally formed.

9. A spout noise reduction device according to any one of claims 4 to 8, wherein a flange (120) is arranged at a spout outlet of the culvert cylinder (100), and the flange (120) is in limit fit with the spoiler (200) in the jet direction of jet flow in the culvert cylinder (100).