CN115881076A - Rudder with additional acoustic black hole - Google Patents
Rudder with additional acoustic black hole Download PDFInfo
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- CN115881076A CN115881076A CN202310033811.0A CN202310033811A CN115881076A CN 115881076 A CN115881076 A CN 115881076A CN 202310033811 A CN202310033811 A CN 202310033811A CN 115881076 A CN115881076 A CN 115881076A
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Abstract
The invention discloses a rudder with an additional acoustic black hole, which relates to the technical field of aerospace and comprises a rudder body and an acoustic black hole structure, wherein a cavity is arranged inside the rudder body, a base is arranged inside the rudder body, the acoustic black hole structure is positioned in the cavity and arranged on the base, and the acoustic black hole structure is detachably connected with the base. According to the wave energy gathering effect and the dynamic vibration absorption principle of the acoustic black hole, the flutter amplitude of the rudder can be reduced to a certain extent by arranging the acoustic black hole structure, and the flutter Mach number, the flutter critical speed and the flutter dynamic pressure of the rudder are improved.
Description
Technical Field
The invention relates to the technical field of aerospace, in particular to a rudder with an additional acoustic black hole.
Background
The flutter refers to the self-excitation vibration of the elastic body with the amplitude increasing continuously under the interaction of aerodynamic force, inertial force and elastic force, and the flutter suppression mainly refers to the tendency of delaying, suppressing or even preventing the amplitude of the elastic body from increasing continuously through a vibration control mode. The existing flutter suppression method mainly comprises two methods of flutter active suppression and flutter passive suppression. The flutter active inhibition is mainly divided into three steps, wherein in the first step, a sensor acquires a vibration response signal of a wing structure; secondly, the control system outputs a related control instruction according to the input vibration response signal; and thirdly, controlling the control command to drive the deflection of the control surface of the wing to adjust the flow field distribution around the wing, thereby achieving the purpose of suppressing the flutter of the wing. The flutter passive suppression is simpler than the flutter active suppression, and the common method is to improve the natural frequency of the wing coupling mode by changing the structure and material properties of the wing and optimizing the mass block counterweight so as to improve the flutter critical speed of the wing and realize the passive flutter suppression of the wing.
The existing flutter active suppression control process is complex, a certain gap exists between the existing flutter active suppression control process and practical application, and most of flutter passive suppression can increase the wing mass and increase the flight cost.
Disclosure of Invention
The invention aims to provide a rudder with an additional acoustic black hole, which solves the problem of the flutter suppression of the rudder by utilizing the dynamic vibration absorber principle and the acoustic black hole effect.
In order to achieve the purpose, the invention provides the following scheme:
the invention provides a rudder with an additional acoustic black hole, which comprises a rudder body and an acoustic black hole structure, wherein a cavity is arranged in the rudder body, a base is arranged in the rudder body, the acoustic black hole structure is positioned in the cavity and arranged on the base, and the acoustic black hole structure is detachably connected with the base.
Preferably, the acoustic black hole structure comprises one or two acoustic black hole assemblies.
Preferably, the acoustic black hole assembly comprises a damping plate and an acoustic black hole, one end of the damping plate is connected with one end of the acoustic black hole, the acoustic black hole is provided with a connecting hole, and the connecting hole is eccentrically arranged.
Preferably, both ends of the damping fin and both ends of the acoustic black hole are planes, one end of the damping fin is connected with the large end of the acoustic black hole, the size of the outer contour of the large end of the acoustic black hole is the same as that of the outer contour of the damping fin, the size of the outer contour of the small end of the acoustic black hole is smaller than that of the outer contour of the large end of the acoustic black hole, a curved surface structure is arranged between the small end of the acoustic black hole and the large end of the acoustic black hole, and the thickness of the curved surface structure is changed according to a power exponent form.
Preferably, the damping fin is annular, and the first through hole of the damping fin is connected with the connecting hole.
Preferably, when the acoustic black hole structure includes two acoustic black hole assemblies, the small end of the acoustic black hole of one acoustic black hole structure passes through the damping piece of the other acoustic black hole structure and is connected with the large end of the acoustic black hole of the other acoustic black hole structure, and the connecting holes of the two acoustic black holes are concentrically arranged.
Preferably, an annular gasket is arranged between the small end of the acoustic black hole of one acoustic black hole structure and the large end of the acoustic black hole of the other acoustic black hole structure, the annular gasket is provided with a second through hole, and the second through hole is concentrically arranged with the connecting hole of each acoustic black hole.
Preferably, both ends of the damping fin and both ends of the acoustic black hole are planes, one end of the damping fin is connected with the large end of the acoustic black hole, a curved surface structure is arranged between the small end of the acoustic black hole and the large end of the acoustic black hole, and the thickness of the curved surface structure is changed according to a power exponent form.
Preferably, the projection of the acoustic black hole on the plane perpendicular to the axis of the connecting hole is in a fan shape, the projection of the damping plate on the plane perpendicular to the axis of the connecting hole is in an arc shape, the damping plate comprises an inner arc edge and an outer arc edge, the inner arc edge is located on the inner side of the outer arc edge, the size of the outer arc edge is the same as that of the arc edge of the acoustic black hole, and the projection of the outer arc edge and the arc edge on the plane perpendicular to the axis of the connecting hole are overlapped.
Compared with the prior art, the invention has the following technical effects:
according to the wave energy gathering effect and the dynamic vibration absorption principle of the acoustic black hole, the flutter amplitude of the rudder can be reduced to a certain extent by arranging the acoustic black hole structure, and the flutter Mach number, the flutter critical speed and the flutter dynamic pressure of the rudder are improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a schematic view of a rudder body of the present invention;
FIG. 2 isbase:Sub>A sectional view taken along line A-A of FIG. 1;
FIG. 3 is an enlarged view of a portion of FIG. 2;
FIG. 4 is a sectional view taken along line B-B of FIG. 1;
FIG. 5 is a bottom view of FIG. 1;
FIG. 6 is an enlarged view of a portion of FIG. 5;
FIG. 7 is a schematic diagram of an acoustic black hole structure according to the present invention (embodiment one);
FIG. 8 is a cross-sectional view taken along line C-C of FIG. 7 (embodiment one);
FIG. 9 is a cross-sectional view taken along line D-D of FIG. 7 (embodiment one);
FIG. 10 is a schematic diagram of the acoustic black hole structure according to the present invention (embodiment II);
FIG. 11 is a cross-sectional view E-E of FIG. 10 (embodiment one);
FIG. 12 is a cross-sectional view F-F of FIG. 10 (embodiment one);
FIG. 13 is a schematic diagram of the acoustic black hole structure according to the present invention (embodiment III);
FIG. 14 is a sectional view taken along line G-G of FIG. 13 (embodiment one);
FIG. 15 is a sectional view taken along line H-H of FIG. 13 (embodiment one);
FIG. 16 is a schematic view of a mass;
FIG. 17 is a schematic illustration of an equal mass disc;
FIG. 18 is a cross-sectional view I-I of FIG. 17;
FIG. 19 is a sectional view taken along line J-J of FIG. 17;
FIG. 20 is a schematic view of a rudder with an attached acoustic black hole according to the present invention (including the acoustic black hole structure in the first embodiment);
FIG. 21 is a schematic view of a rudder with an additional acoustic black hole according to the present invention (including the acoustic black hole structure in the second embodiment);
FIG. 22 is a schematic view of a rudder with an attached acoustic black hole according to the present invention (including the acoustic black hole structure in the third embodiment);
FIG. 23 is a schematic view of the mass mounted to the rudder body;
FIG. 24 is a schematic view of the mounting of the constant mass disc to the rudder body;
FIG. 25 is a plot of flutter displacement critical response for a rudder with a mass and a rudder with an iso-mass disc;
FIG. 26 is a plot of rudder flutter threshold response for a rudder with an equivalent mass disk and an embodiment rudder with an attached acoustic black hole;
FIG. 27 is a plot of flutter critical displacement response for an equimass disk (dashed line) and a rudder body (solid line) containing an equimass disk with 2.20Ma of air flowing down;
FIG. 28 is a graph of flutter critical displacement response for an attached acoustic black hole (dashed line) and a rudder (solid line) containing an attached acoustic black hole with air flowing down 2.35 Ma;
wherein: the rudder comprises a rudder body 1, a cavity 2, a base 3, a wing tip surface 4, a wing root surface 5, a rudder shaft axis 6, a boundary condition area 7, a damping sheet 8, an acoustic black hole 9, a connecting hole 10, a mass disc structure 11, a first through hole 12, a gasket 13, a mass block 14, an annular damping sheet 15 and a disc 16.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.
The invention aims to provide a rudder with an additional acoustic black hole, which solves the problem of the flutter suppression of the rudder by utilizing the dynamic vibration absorber principle and the acoustic black hole effect.
In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, the present invention is described in detail with reference to the accompanying drawings and the detailed description thereof.
Example one
The acoustic black hole effect is that the phase velocity and the group velocity of a wave propagating in a structure are changed by using the change of the impedance of the structure, so that the wave is gathered in a specific area of the structure. If the thickness of the cross section of the structure is reduced to the minimum value which can be processed by materials according to a certain power index, when the transverse wave of the structure vibration is transmitted to the tip region of the variable-thickness cross section, the vibration amplitude of the transverse wave can be gradually increased, and then the damping material pasted on the tip region of the structure is utilized to realize the effective dissipation of the vibration energy.
As shown in fig. 1 to 9: the embodiment provides a rudder that contains black hole of additional formula acoustics, including rudder body 1 and the black hole structure of acoustics, the inside of rudder body 1 is provided with cavity 2, and the inside of rudder body 1 is provided with base 3, and base 3 is provided with the hole, and the black hole structure of acoustics is located cavity 2 and sets up on base 3, and the black hole structure of acoustics does not contact with the inner wall of rudder body 1, and the black hole structure of acoustics passes through the bolt with base 3 and can be connected with dismantling. The position of the base 3 changes with the installation position of the acoustic black hole structure, but different installation positions of the acoustic black hole structure have completely different effects on the flutter of the rudder body 1. The optimal installation position of the base 3 is located at the position (based on the view angle of fig. 1) of the rightmost side of the rudder body 1, which is close to the wing tip surface 4, and at this time, the vibration displacement amplitude of the base 3 is large, so that the optimal dynamic vibration absorption effect is achieved. The rudder body 1 serves as a main body structure of the dynamic vibration absorber, and the acoustic black hole structure serves as an additional structure of the dynamic vibration absorber. When the vibration frequency (flutter frequency) caused by the aerodynamic force acting on the main body structure is equal to the natural frequency of the additional structure, the additional structure and the main body structure can generate a dynamic vibration absorption effect, namely, the rudder body 1 transmits part of vibration energy to the acoustic black hole structure to cause severe vibration of the acoustic black hole structure, so that dynamic vibration absorption is realized.
Specifically, in this embodiment, the rudder body 1 is an improved version of the HD3103B rudder model, the small end of the rudder body 1 is a wing tip surface 4, the large end of the rudder body 1 is a wing root surface 5, a rudder shaft is arranged in the rudder body 1, and the rudder body 1 rotates around an axis 6 of the rudder shaft.
In this embodiment, the acoustic black hole structure includes an acoustic black hole 9 assembly.
In this embodiment, the acoustic black hole 9 assembly includes a damping plate 8 and an acoustic black hole 9, one end of the damping plate 8 is connected with one end of the acoustic black hole 9 through glue, the acoustic black hole 9 is provided with a connecting hole 10, and the connecting hole 10 is eccentrically arranged.
In this embodiment, both ends of the damping fin 8 and both ends of the acoustic black hole 9 are planes, one end of the damping fin 8 is connected with the large end of the acoustic black hole 9, the outer contour size of the large end of the acoustic black hole 9 is the same as that of the damping fin 8, the outer contour size of the small end of the acoustic black hole 9 is smaller than that of the large end of the acoustic black hole 9, a curved surface structure is arranged between the small end of the acoustic black hole 9 and the large end of the acoustic black hole 9, the curved surface structure is an irregular curved surface structure, and the irregular curved surface structure has a certain thickness. The projection distance from one point of the irregular curved surface to the end face of the big end of the acoustic black hole 9 is the thickness of the irregular curved surface, the thickness direction of the irregular curved surface is parallel to the axis of the connecting hole 10, the thickness of the irregular curved surface changes from the edge of the acoustic black hole 9 to the center of the connecting hole 10 according to a certain power exponent, and the curved surface structure has the basic characteristic of energy gathering of the acoustic black hole 9.
In this embodiment, the damping fin 8 is annular, the damping fin 8 has a certain thickness, and the first through hole 11 and the connecting hole 10 of the damping fin 8.
Example two
As shown in fig. 10 to 12, the present embodiment is different from the first embodiment in that: in this embodiment, when the acoustic black hole structure includes two acoustic black hole 9 assemblies, the small end of the acoustic black hole 9 of one acoustic black hole structure passes through the damping plate 8 of the other acoustic black hole structure and is connected with the large end of the acoustic black hole 9 of the other acoustic black hole structure, the connecting holes 10 of the two acoustic black holes 9 are concentrically arranged, and the acoustic black hole 9 of the other acoustic black hole structure is connected with the base 3.
In this embodiment, an annular gasket 12 is arranged between the small end of the acoustic black hole 9 of one acoustic black hole structure and the large end of the acoustic black hole 9 of another acoustic black hole structure, the annular gasket 12 is provided with a second through hole, the second through hole is concentrically arranged with the connecting hole 10 of each acoustic black hole 9, the annular gasket 12 is made of ceramic or other metal materials with high hardness, thereby not only avoiding the mutual contact of the outer edges of the two acoustic black hole structures, but also being beneficial to transmitting the vibration energy efficient of the acoustic black hole structure fixed on the rudder body 1 to another acoustic black hole structure which is not in direct contact with the rudder body 1, ensuring that the two structures can well absorb the vibration energy, and realizing stronger damping consumption.
Compared with the acoustic black hole structure including one acoustic black hole 9 component in the first embodiment, the acoustic black hole structure including two acoustic black hole 9 components in the present embodiment has a stronger flutter suppression effect on the rudder body 1 (as shown in fig. 21). When flutter occurs, because the energy accumulated and absorbed by the double-layer acoustic black hole structure is greater than the energy accumulated and absorbed by the single-layer acoustic black hole structure, when more energy of the rudder body 1 is transferred to the double-layer acoustic black hole structure, the flutter critical state of the equal-amplitude vibration of the rudder body 1 needs to be maintained, the acting of aerodynamic force on the rudder body 1 needs to be increased, and the incoming flow speed needs to be increased.
EXAMPLE III
As shown in fig. 13 to 15, the present embodiment is different from the first embodiment in that: in this embodiment, both ends of the damping fin 8 and both ends of the acoustic black hole 9 are planes, one end of the damping fin 8 is connected with the large end of the acoustic black hole 9, a curved surface structure is arranged between the small end of the acoustic black hole 9 and the large end of the acoustic black hole 9, and the thickness of the curved surface structure changes according to the form of power exponent.
In this embodiment, the projection of the acoustic black hole 9 on the plane perpendicular to the axis of the connection hole 10 is in a fan shape, the projection of the damping fin 8 on the plane perpendicular to the axis of the connection hole 10 is in an arc shape, the damping fin 8 includes an inner arc edge and an outer arc edge, the inner arc edge is located on the inner side of the outer arc edge, the outer arc edge has the same size as the arc edge of the acoustic black hole 9, and the outer arc edge and the arc edge coincide with each other in the projection of the arc edge on the plane perpendicular to the axis of the connection hole 10.
In this embodiment, the acoustic black hole structure is an eccentric grooving structure, and is formed by improving the acoustic black hole structure of the first embodiment, two straight lines tangent to the small-end circular edge are used as cutting paths, and the two straight lines are obtained by cutting twice with a certain included angle. The acoustic black hole structure of the eccentric slotted groove structure can adjust the installation direction according to the maximum vibration displacement amplitude of the rudder body 1 to find the optimal energy absorption angle.
For the acoustic black hole structure of the eccentric slotted structure shown in fig. 13, different slotted angles correspond to different natural frequencies, and the front two-step natural frequencies of the acoustic black hole structure of the eccentric slotted structure are matched with the natural frequency of the flutter of the rudder body 1 by finding out a proper slotted angle, which is more favorable for the occurrence of dynamic vibration absorption.
Compared with the acoustic black hole structure including one acoustic black hole 9 component in the first embodiment, the acoustic black hole structure of the eccentric notched structure in the first embodiment has a more efficient flutter suppression effect on the rudder body 1.
The experimental comparisons are as follows:
the flight environment of the rudder body 1 is mach 1.5-5 supersonic air incoming flow, the incoming flow direction is from left to right (based on the view angle of figure 1), and the incoming flow direction is parallel to the wing tip surface 4 and the wing root surface 5. When a wind tunnel experiment is carried out, the wing root surface 5 faces downwards vertically, and the wing tip surface 4 is placed upwards vertically, so that static deformation of the rudder body 1 bending around a rudder shaft due to gravity factors is counteracted.
For the convenience of analysis during simulation, the displacement boundary condition of the rudder body 1 can be set in the middle of the wing root surface 5, and the boundary condition area 7 mainly consists of a middle circle and two sides of rectangles. The circular area is set to be displacement full restraint, namely the circular area is kept fixed, the rectangular areas on the two sides are set to be displacement restraint perpendicular to the wing root surface 5, namely the rectangular areas on the two sides do not have displacement perpendicular to the wing root surface 5, and the two kinds of restraint are used for simulating the fixed connection of the rudder body 1 and the rudder shaft. Solving the flutter critical displacement response of the rudder body 1 containing different acoustic black hole structures at different incoming flow speeds by using an ANSYS & Fluent bidirectional fluid-solid coupling method.
Control group one: mass block 13
As shown in fig. 16, the mass 13 is a solid cylinder, and the material of the mass 13 may be selected from materials with high density and small volume such as iron and lead, or conventional aluminum alloy materials, as long as the mass 13 can be normally mounted on the base 3 of the rudder body 1.
As shown in fig. 23, the mass block 13 is mounted on the rudder body 1, and then bidirectional flow coupling solving analysis is performed at different incoming flow mach numbers to obtain the flutter critical response of the rudder body 1 including the mass block 13.
Control group two: the constant mass disk structure 14 (the mass 13, the constant mass disk structure 14 and the acoustic black hole structure have the same mass)
As shown in fig. 17 to 19, the constant-mass disc structure 14 includes a ring-shaped damper 15 and a disc 16, and one end of the ring-shaped damper 15 is connected to one end of the disc 16 by glue. The annular damping fin 15 has a certain thickness, and the annular damping fin 15 is made of butyl rubber material or other replaceable materials with large damping coefficients. The disc 16 is provided with an eccentrically arranged round hole which is used for being connected with the base 3, and the outer ring of the round hole is provided with a round marking line which plays a guiding role when the disc 16 and the base 3 are assembled.
As shown in fig. 24, the equal-mass disc structure 14 is mounted on the rudder body 1, and then bidirectional flow coupling solving analysis is performed at different incoming flow mach numbers to obtain the flutter critical response of the rudder body 1 including the equal-mass disc 14.
Experiment group one: the acoustic black hole structure comprises an acoustic black hole 9 assembly
As shown in fig. 20, the acoustic black hole structure is installed on the rudder body 1, and then bidirectional flow coupling solving analysis is performed at different incoming flow mach numbers to obtain a flutter critical response of the rudder body 1 including an acoustic black hole 9 component.
Fig. 25 shows the flutter critical displacement response of the rudder with the equal mass and the rudder with the equal mass disc, where the flutter mach number of the rudder with the equal mass is 2.18Ma and the flutter mach number of the rudder with the mass disc is 2.20Ma, which shows that the equal mass disc has a preliminary flutter suppression effect on the rudder. Fig. 26 shows the critical response to flutter of a rudder having an equivalent mass and a rudder having an acoustic black hole structure according to an embodiment, and the critical mach number of flutter of the rudder having an acoustic black hole structure according to an embodiment is 2.35Ma, which shows that the acoustic black hole structure can further suppress flutter of the rudder. Comparing the amplitudes of the displacement response curves in fig. 25 and fig. 26, it can be found that the maximum displacement response amplitude of the rudder body 1 including the equal mass disc 14 is reduced by 31.44% compared with the maximum displacement response amplitude of the rudder body 1 including the equal mass block 13, and the maximum displacement response amplitude of the rudder body 1 including the acoustic black hole structure is reduced by 48.48% compared with the maximum displacement response amplitude of the rudder body 1 including the equal mass block 13, which indicates that both the equal mass disc 14 and the acoustic black hole structure can well reduce the flutter response amplitude of the rudder body 1, and the flutter amplitude reduction effect of the acoustic black hole structure on the rudder body 1 is more obvious.
Fig. 27 shows the flutter critical displacement response of the equal mass disk 14 (dashed line) and the rudder body 1 (solid line) containing the equal mass disk, with the average vibration response amplitude of the equal mass disk 14 and the average vibration response amplitude of the rudder body 1 approximately equal, when air of 2.20Ma flows down. Fig. 28 shows flutter critical displacement responses of an additional acoustic black hole (dotted line) and a rudder (solid line) including the additional acoustic black hole, under air inflow of 2.35Ma, in which the average vibration response amplitude of the additional acoustic black hole is about 3 times that of the rudder body 1. The results of fig. 27 and 28 illustrate that the acoustic black hole add-on structure 9 transfers and absorbs more vibration energy from the rudder body 1, and in order to maintain the constant amplitude vibration of the rudder body 1, the rudder with the acoustic black hole add-on needs to further increase the incoming flow mach number to increase the work of aerodynamic force on the rudder body 1, which also results in why the rudder flutter mach number of the acoustic black hole add-on structure is larger than that of the constant mass disc rudder.
Compared with the mass 13 and the equal mass disc 14, the acoustic black hole structure has a better flutter suppression effect on the rudder body 1. Because the mass factors can greatly influence the flutter of the rudder body 1, the mass of the mass block 13, the equal mass disc structure 14 and the mass of the acoustic black hole structure are set to be the same, so that the influence of the mass factors on the flutter result is avoided. Although the equal-mass disc 14 and the acoustic black hole structure have rich modes, the equal-mass disc 14 and the acoustic black hole structure can be well frequency-matched with the structure of the rudder body 1, and both have a dynamic vibration absorption effect, and can perform effective energy transfer, but the energy gathering effect of the acoustic black hole structure, namely, the energy of the rudder body 1 and the energy transferred to the acoustic black hole structure through dynamic vibration absorption can be subjected to the energy gathering effect of the acoustic black hole structure, and the energy is better transferred to the edge of the acoustic black hole structure to perform damping consumption, and the final expression form is that under the same incoming current condition, the damping of the acoustic black hole structure is more than that of the equal-mass disc 14, and in order to maintain the flutter critical state of the rudder body 1, the incoming current speed needs to be improved to increase the acting of aerodynamic force on the rudder body 1.
In conclusion, the acoustic black hole structure not only can play a good role in inhibiting the flutter of the rudder body 1, but also has obvious advantages. Research results show that under the same quality condition, the flutter amplitude of the rudder body 1 with the acoustic black hole structure is reduced compared with that of the rudder body 1 without the acoustic black hole structure, and the flutter critical speed is obviously improved. The specific advantages are mainly embodied in the following two aspects: first, the control method for suppressing the rudder chatter is simple. Conventional active flutter suppression
The vibration of the rudder main body 1 needs to be suppressed by a complex pneumatic servo control law, but in the embodiment 5, the vibration of the rudder main body 1 can be suppressed by simply installing an additional acoustic black hole structure inside the rudder main body 1, and the vibration control effect is obvious. Second, flight costs are significantly reduced. Although the quality of the rudder body can well inhibit the flutter of the rudder, the takeoff weight of the airplane is increased, and the oil consumption cost is increased. The acoustic black hole structure of the embodiment has a small volume, the mass ratio of the acoustic black hole structure is less than 3% of the mass of the rudder body 1, and the flying cost of the aircraft is not increased.
0 the principles and embodiments of this invention have been described herein using specific examples,
the above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core ideas; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.
Claims (9)
1. A rudder with an additional acoustic black hole, comprising: including rudder body and acoustics black hole structure, the inside of rudder body is provided with the cavity, the inside of rudder body is provided with the base, acoustics black hole structure is located in the cavity and setting up on the base, acoustics black hole structure with the base can be connected with dismantling.
2. The rudder with an attached acoustic black hole of claim 1, wherein: the acoustic black hole structure includes one or two acoustic black hole assemblies.
3. The rudder with an attached acoustic black hole of claim 2, wherein: the acoustic black hole assembly comprises a damping sheet and an acoustic black hole, one end of the damping sheet is connected with one end of the acoustic black hole, the acoustic black hole is provided with a connecting hole, and the connecting hole is eccentrically arranged.
4. The rudder with an attached acoustic black hole of claim 3, wherein: the two ends of the damping sheet and the two ends of the acoustic black hole are both planes, one end of the damping sheet is connected with the large end of the acoustic black hole, the size of the outer contour of the large end of the acoustic black hole is the same as that of the outer contour of the damping sheet, the size of the outer contour of the small end of the acoustic black hole is smaller than that of the outer contour of the large end of the acoustic black hole, a curved surface structure is arranged between the small end of the acoustic black hole and the large end of the acoustic black hole, and the thickness of the curved surface structure is changed according to the form of power indexes.
5. The rudder with an attached acoustic black hole of claim 3, wherein: the damping fin is annular, the first through-hole of damping fin with the connecting hole.
6. The rudder with an attached acoustic black hole of claim 3, wherein: when the acoustic black hole structure comprises two acoustic black hole assemblies, the small end of the acoustic black hole of one acoustic black hole structure penetrates through the damping sheet of the other acoustic black hole structure and is connected with the large end of the acoustic black hole of the other acoustic black hole structure, and the connecting holes of the two acoustic black holes are concentrically arranged.
7. The rudder with an attached acoustic black hole of claim 6, wherein: an annular gasket is arranged between the small end of the acoustic black hole of one acoustic black hole structure and the large end of the acoustic black hole of the other acoustic black hole structure, the annular gasket is provided with a second through hole, and the second through hole and the connecting hole of each acoustic black hole are concentrically arranged.
8. The rudder with an attached acoustic black hole of claim 3, wherein: the two ends of the damping sheet and the two ends of the acoustic black hole are both planes, one end of the damping sheet is connected with the large end of the acoustic black hole, a curved surface structure is arranged between the small end of the acoustic black hole and the large end of the acoustic black hole, and the thickness of the curved surface structure changes according to the form of power exponent.
9. The rudder with an attached acoustic black hole of claim 8, wherein: the projection of the acoustic black hole on the plane perpendicular to the axis of the connecting hole is fan-shaped, the projection of the damping sheet on the plane perpendicular to the axis of the connecting hole is arc-shaped, the damping sheet comprises an inner arc edge and an outer arc edge, the inner arc edge is positioned on the inner side of the outer arc edge, the outer arc edge is the same as the radian edge of the acoustic black hole in size, and the outer arc edge is overlapped with the projection of the radian edge on the plane perpendicular to the axis of the connecting hole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310033811.0A CN115881076A (en) | 2023-01-10 | 2023-01-10 | Rudder with additional acoustic black hole |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310033811.0A CN115881076A (en) | 2023-01-10 | 2023-01-10 | Rudder with additional acoustic black hole |
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| CN115881076A true CN115881076A (en) | 2023-03-31 |
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| CN202310033811.0A Pending CN115881076A (en) | 2023-01-10 | 2023-01-10 | Rudder with additional acoustic black hole |
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2023
- 2023-01-10 CN CN202310033811.0A patent/CN115881076A/en active Pending
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