Vortex-isolating, vibration-damping, noise-eliminating and noise-reducing device for
By using perforated plates and sound-absorbing and noise reduction devices of exhaust slots with perforated plates and sound-absorbing materials in a pneumatic acoustic wind tunnel, the problem of jet noise in exhaust slots is solved, and the effect of reducing jet velocity and noise is achieved, which is improved. Wind tunnel experimental environment.
Patent Information
- Application Number
- CN202411259196.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-09
- Publication Date
- 2024-12-27
AI Technical Summary
In a pneumatic acoustic open reflow wind tunnel, the exhaust slot jet noise leads to excessive background noise, affecting the accuracy of acoustic experimental measurements. The existing control methods are insufficient and a new noise reduction device is needed.
Design a vortex vibration damping and noise reduction device for exhaust slits, using perforated plates and internal sound absorbing materials. The perforated plates are arranged on the side wall of the shell, and the sound absorbing materials fill the cavity. Felt is pasted on the outer surface to reduce jet noise and partition Vortex structure.
Effectively reduce the jet velocity and noise at the exhaust slot, improve the experimental environment conditions of the wind tunnel, and improve measurement accuracy.
Smart Images
Figure CN119207352A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of noise reduction, and in particular to an exhaust slot vortex isolation vibration reduction and noise reduction device. Background Art
[0002] The aeroacoustic wind tunnel is a key experimental equipment for aerodynamic research. In an aeroacoustic open reflow wind tunnel, the exhaust slit is located close to the test section. However, since gas will overflow from the exhaust slit to form a jet, significant jet noise will be generated, resulting in too high background noise in the wind tunnel, affecting the accuracy of acoustic experimental measurements. At present, there are relatively insufficient control methods for exhaust slit jet noise, and a new noise reduction device is urgently needed to effectively reduce this noise source, thereby improving the measurement results and environmental conditions of wind tunnel experiments. Summary of the invention
[0003] The purpose of the present invention is to provide an exhaust slot vortex isolation, vibration reduction, and noise reduction device to solve the problems existing in the above-mentioned prior art. It can effectively reduce the jet velocity at the exhaust slot, and isolate the vortex structure at the exhaust slot, and use a perforated plate and internal sound-absorbing material to reduce the jet noise.
[0004] To achieve the above object, the present invention provides the following solutions:
[0005] The present invention provides an exhaust slot vortex isolation, vibration reduction, sound absorption and noise reduction device, which is used to be arranged on the outside of the exhaust slot of an open wind tunnel, and comprises: an outer shell and a sound absorbing structure, a cavity is formed inside the outer shell, the sound absorbing structure is located in the cavity, the side wall of the outer shell is made of a perforated plate, the perforated plate is provided with a plurality of perforations, and the sound absorbing structure is made of a sound absorbing material.
[0006] Preferably, the perforated plate is made of galvanized steel plate.
[0007] Preferably, the thickness of the exhaust slot vortex isolation, vibration reduction, sound reduction and noise reduction device is 300 mm, and the length of the exhaust slot vortex isolation, vibration reduction, sound reduction and noise reduction device is 980 mm.
[0008] Preferably, the perforated plate has a thickness of 2.5 mm.
[0009] Preferably, the perforation rate of the perforated plate is 30%.
[0010] Preferably, the outer surface of the housing is provided with felt.
[0011] Preferably, the distance between the exhaust slot vortex isolation, vibration reduction, and noise reduction device and the exhaust slot is 300 mm.
[0012] Preferably, the bulk density of the sound absorbing material is 32 kg / m3.
[0013] Preferably, the sound absorbing material is glass wool.
[0014] Preferably, the exterior of the sound absorbing structure is wrapped with alkali-free glass cloth.
[0015] Compared with the prior art, the present invention has achieved the following technical effects:
[0016] The present invention adds an exhaust slot vortex isolation, vibration reduction, sound elimination and noise reduction device on the outer side of the exhaust slot of the open wind tunnel, and the interior of the outer shell is filled with sound-absorbing material. The jet at the exhaust slot directly hits the surface of the exhaust slot vortex isolation, vibration reduction, sound elimination and noise reduction device, which can directly reduce the central velocity of the jet, and the exhaust slot vortex isolation, vibration reduction, sound elimination and noise reduction device can isolate the vortex structure at the exhaust slot outlet, thereby reducing the jet noise. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0018] Figure 1 It is a cross-sectional view of the internal structure of the exhaust slot vortex isolation vibration reduction and noise reduction device of the present invention applied to the reflow type wind tunnel noise reduction chamber;
[0019] Figure 2 It is a schematic diagram of the internal structure of the exhaust slot vortex isolation vibration reduction and noise reduction device of the present invention applied to the reflow wind tunnel noise reduction chamber;
[0020] In the figure: 1- shell, 2- sound absorbing structure, 3- exhaust slit. DETAILED DESCRIPTION
[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0022] The purpose of the present invention is to provide an exhaust slot vortex isolation, vibration reduction, and noise reduction device to solve the problems existing in the above-mentioned prior art. It can effectively reduce the jet velocity at the exhaust slot, and isolate the vortex structure at the exhaust slot, and use a perforated plate and internal sound-absorbing material to reduce the jet noise.
[0023] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.
[0024] like Figure 1 to Figure 2 As shown, the present embodiment provides an exhaust slot vortex isolation, vibration reduction, sound absorption and noise reduction device, which is used to be arranged on the outside of the exhaust slot 3 of an open wind tunnel, and the exhaust slot vortex isolation, vibration reduction, sound absorption and noise reduction device comprises: an outer shell 1 and a sound absorbing structure 2, the size of the outer shell 1 can cover the exhaust slot 3, the outer shell 1 comprises an inner wall, an outer wall, a front side wall and a rear side wall, the interior of the outer shell 1 forms a cavity with a rectangular cross-section, the sound absorbing structure 2 is located in the cavity, the inner wall, the outer wall, the front side wall and the rear side wall are all made of perforated plates, the perforated plates are provided with a plurality of perforations, and the sound absorbing structure 2 is made of sound absorbing material.
[0025] Specifically, in this embodiment, the perforated plate is made of galvanized steel plate, the thickness of the perforated plate is 2.5 mm, the perforation rate of the perforated plate is 30%, and the outer surface of the shell 1 is pasted with felt to reduce the impact noise generated by the jet directly hitting the perforated plate.
[0026] In this embodiment, the thickness of the exhaust slot vortex isolation vibration reduction and noise reduction device is 300 mm, the length of the exhaust slot vortex isolation vibration reduction and noise reduction device is 980 mm, and the distance between the inner side of the exhaust slot vortex isolation vibration reduction and noise reduction device and the exhaust slot 3 is 300 mm.
[0027] In this embodiment, the sound absorbing material is Owens environmentally friendly glass wool, and the bulk density of the sound absorbing material is 32kg / m 3 The outside of the sound absorbing structure 2 is wrapped with alkali-free glass cloth to prevent the precipitation of glass wool.
[0028] In this embodiment, an exhaust slot vortex isolation, vibration reduction, and noise reduction device is added to the outside of the open wind tunnel exhaust slot 3, and the interior is filled with sound-absorbing material. The outer shell 1 directly reduces the center velocity of the jet and isolates the vortex structure at the outlet, thereby reducing the jet noise. At the same time, felt is pasted on the outer surface of the perforated plate to reduce the impact noise generated by the jet hitting the hard wall.
[0029] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.
Claims
1. An exhaust slit vortex isolation vibration reduction and noise reduction device, characterized in that: The exhaust slot vortex isolation, vibration reduction, sound absorption and noise reduction device is used to be arranged on the outside of the exhaust slot of an open wind tunnel, and the exhaust slot vortex isolation, vibration reduction, sound absorption and noise reduction device includes: an outer shell and a sound absorbing structure, the interior of the outer shell forms a cavity, the sound absorbing structure is located in the cavity, the side wall of the outer shell is made of a perforated plate, the perforated plate is provided with a plurality of perforations, and the sound absorbing structure is made of a sound absorbing material.
2. The exhaust slit vortex isolation vibration reduction and noise reduction device according to claim 1, characterized in that: The perforated plate is made of galvanized steel plate.
3. The exhaust slit vortex isolation vibration reduction and noise reduction device according to claim 1, characterized in that: The thickness of the exhaust slot vortex isolation, vibration reduction, sound reduction and noise reduction device is 300 mm, and the length of the exhaust slot vortex isolation, vibration reduction, sound reduction and noise reduction device is 980 mm.
4. The exhaust slot vortex isolation vibration reduction and noise reduction device according to claim 1, characterized in that: The thickness of the perforated plate is 2.5 mm.
5. The exhaust slit vortex isolation vibration reduction and noise reduction device according to claim 1, characterized in that: The perforation rate of the perforated plate is 30%.
6. The exhaust slot vortex isolation vibration reduction and noise reduction device according to claim 1, characterized in that: The outer surface of the shell is provided with felt.
7. The exhaust slit vortex isolation vibration reduction and noise reduction device according to claim 1, characterized in that: The distance between the exhaust slot vortex isolation, vibration reduction, noise reduction device and the exhaust slot is 300 mm.
8. The exhaust slot vortex isolation vibration reduction and noise reduction device according to claim 1, characterized in that: The bulk density of the sound absorbing material is 32 kg / m 3 .
9. The exhaust slit vortex isolation vibration reduction and noise reduction device according to claim 1, characterized in that: The sound absorbing material is glass wool.
10. The exhaust slit vortex isolation vibration reduction and noise reduction device according to claim 1, characterized in that: The outside of the sound absorbing structure is wrapped with alkali-free glass cloth.