Noise reduction device and centrifugal compressor

Abstract

The application discloses a noise reduction device and a centrifugal compressor, and relates to the technical field of compressor equipment. The main purpose of the noise reduction device is to absorb high-energy noise generated by impeller rotation at one and two times of blade passing frequency, reduce the noise intensity of the centrifugal compressor air inlet and air outlet pipeline outward propagation, and reduce the noise pollution to the surrounding environment and on-site workers during the operation of the centrifugal compressor. The main technical scheme of the application is that the noise reduction device comprises a sound absorption pipeline, a first sound absorption module and a second sound absorption module are sequentially arranged in the sound absorption pipeline along a flow direction, the first sound absorption module comprises a first perforated plate, the first perforated plate is used for absorbing noise in a first frequency range, the second sound absorption module comprises a second perforated plate and a third perforated plate, the third perforated plate is arranged on the radial outer side of the second perforated plate, and the third perforated plate and the second perforated plate are used for absorbing noise in a second frequency range.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of compressor equipment, and particularly relates to a noise reduction device and centrifugal compressor. BACKGROUND

[0002] In the fields of petroleum chemical industry, natural gas storage and transportation, and electric power which have a key influence on the national economy, large centrifugal compressor units play an important role as core power equipment. However, a large amount of aerodynamic noise is generated when the unit is running, and the noise is radiated outward through the inlet and outlet pipelines, causing serious noise pollution. This pollution not only harms the physical and mental health of the on-site workers, but also has a great adverse effect on the surrounding living environment.

[0003] At present, the aerodynamic noise generated by the large centrifugal compressor mainly includes discrete noise and broadband noise. Among them, the discrete noise generated by the dynamic and static interference dominates the overall noise, especially the noise of the one-time and two-time blade passing frequencies caused by the rotation of the impeller, and the sound energy of which is at the highest level among all noise components. SUMMARY

[0004] Therefore, the application provides a noise reduction device and centrifugal compressor. The main purpose of the noise reduction device is to absorb the high-energy noise generated by the rotation of the impeller at the one-time and two-time blade passing frequencies, reduce the noise intensity of the centrifugal compressor inlet and outlet pipeline outward propagation, and reduce the noise pollution to the surrounding environment and on-site workers during the operation of the centrifugal compressor.

[0005] To achieve the above purpose, the application mainly provides the following technical scheme:

[0006] In a first aspect of the application, a noise reduction device is provided, which comprises a sound absorption pipeline, a first sound absorption module and a second sound absorption module are sequentially arranged in the sound absorption pipeline along the flow direction, the first sound absorption module comprises a first perforated plate, the first perforated plate is used to absorb noise in a first frequency range, the second sound absorption module comprises a second perforated plate and a third perforated plate, the third perforated plate is arranged on the radial outer side of the second perforated plate, and the third perforated plate and the second perforated plate are used to absorb noise in a second frequency range.

[0007] Optionally, the thickness of the first perforated plate is 0.5mm-1.5mm, and the perforation rate of the first perforated plate is 3%-15%;

[0008] The thickness of the second perforated plate is 1mm-2.5mm, and the perforation rate of the second perforated plate is 3%-15%;

[0009] The thickness of the third perforated plate is 0.5mm-1.5mm, and the perforation rate of the third perforated plate is 1%-5%.

[0010] Optionally, the first perforated plate is provided with a plurality of first sound absorption holes, the diameter of the first sound absorption hole is 1mm-2.5mm, and the interval distance between two adjacent first sound absorption holes is 11mm.

[0011] The second perforated plate is provided with a plurality of second sound absorption holes, the diameter of the second sound absorption hole is 1mm-2.5mm, and the interval distance between two adjacent second sound absorption holes is 12mm.

[0012] The third perforated plate is provided with a plurality of third sound absorption holes, the diameter of the third sound absorption hole is 0.5mm-1.5mm, and the interval distance between two adjacent third sound absorption holes is 13mm.

[0013] Optionally, the plurality of first sound absorption holes, the plurality of second sound absorption holes and the plurality of third sound absorption holes are distributed in an equilateral triangle shape.

[0014] Optionally, the first sound absorption module further comprises a first honeycomb core and an annular back plate, the first honeycomb core is arranged on the radial outer side of the first perforated plate, and the annular back plate is arranged between the outer wall of the first honeycomb core and the inner wall of the sound absorption pipeline.

[0015] Optionally, the thickness of the first honeycomb core is 11mm-61mm, and the basic unit shape of the first honeycomb core is a regular hexagon.

[0016] Optionally, the second sound absorption module further comprises a second honeycomb core and an annular rib plate, the second honeycomb core is arranged between the second perforated plate and the third perforated plate, and the annular rib plate is arranged between the outer wall of the third perforated plate and the inner wall of the sound absorption pipeline.

[0017] Optionally, the basic unit shape of the second honeycomb core is also a regular hexagon, and the thickness of the second honeycomb core and the annular rib plate is 5mm-30mm.

[0018] Optionally, the noise reduction device further comprises a butt flange, and the butt flange is arranged at the end of the sound absorption pipeline.

[0019] The second aspect of the present application provides a centrifugal compressor comprising the noise reduction device described in any one of the above.

[0020] By means of the above technical scheme, the present application has at least the following beneficial effects:

[0021] The embodiment of the present application provides a noise reduction device and a centrifugal compressor, the noise reduction device can absorb noise in a first frequency range and a second frequency range respectively by arranging a first sound absorption module and a second sound absorption module, so that high-energy noise generated by rotation of a centrifugal compressor impeller at one times and two times blade passing frequencies can be continuously treated in a propagation process, thereby reducing noise intensity radiated outward by the centrifugal compressor and reducing noise pollution on the surrounding environment and on-site workers during operation of the centrifugal compressor. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 A structural schematic diagram of a noise reduction device of one optional embodiment of the present application is shown in the figure.

[0023] Figure 2 A partial enlarged view of a first perforated plate in the noise reduction device shown in the figure. Figure 1

[0024] Figure 3 A structural schematic diagram of the first perforated plate of one optional embodiment of the present application is shown in the figure.

[0025] Figure 4 A partial enlarged view of a first honeycomb core in the noise reduction device shown in the figure. Figure 1

[0026] A structural schematic diagram of the first honeycomb core of one optional embodiment of the present application is shown in the figure. Figure 5

[0027] Figure 6 A partial enlarged view of a second perforated plate in the noise reduction device shown in the figure. Figure 1

[0028] A structural schematic diagram of the second perforated plate of one optional embodiment of the present application is shown in the figure. Figure 7

[0029] A partial enlarged view of a third perforated plate in the noise reduction device shown in the figure. Figure 8 Figure 1 A structural schematic diagram of the third perforated plate of one optional embodiment of the present application is shown in the figure.

[0030] Figure 9 A partial enlarged view of a second honeycomb core in the noise reduction device shown in the figure.

[0031] Figure 10 Figure 1 A structural schematic diagram of the second honeycomb core of one optional embodiment of the present application is shown in the figure.

[0032] Figure 11

[0033] The reference signs are represented as:

[0034] ​​​​​1, sound absorption duct; 2, first sound absorption module; 21, first perforated plate; 211, first sound absorption hole; 22, first honeycomb core; 23, annular back plate; 3, second sound absorption module; 31, second perforated plate; 311, second sound absorption hole; 32, third perforated plate; 321, third sound absorption hole; 33, second honeycomb core; 34, annular rib plate; 4, connecting flange. DETAILED DESCRIPTION

[0035] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0036] In addition, the terms "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first" and "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly specified and limited.

[0037] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0038] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings, and it should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0039] The embodiments of the first aspect of the present application provide a noise reduction device, and the embodiments of the second aspect of the present application provide a centrifugal compressor.

[0040] The noise reduction device is used in the centrifugal compressor.

[0041] Specifically, the noise reduction device is arranged at the inlet and outlet pipe of the centrifugal compressor, aiming to effectively control the noise generated during the operation of the centrifugal compressor from the source. It can be understood that when the centrifugal compressor is working, the inlet and outlet pipe is the main way of propagation of aerodynamic noise, especially the high-energy noise at the blade passing frequency caused by the rotation of the impeller, which will propagate in the pipe with the airflow and radiate outward. The above-mentioned noise reduction device is installed at the inlet and outlet pipe, which can directly act on the noise, effectively intercept and absorb the energy of the passing noise wave, thereby reducing the noise intensity radiated from the inlet and outlet pipe, and effectively alleviating the noise pollution problem caused by the centrifugal compressor to the surrounding environment and the on-site workers, ensuring the comfort and safety of the working environment.

[0042] Herein, referring to Figures 1 to 11 The noise reduction device provided by the embodiment of the first aspect of the present application comprises a sound absorption pipeline 1, a first sound absorption module 2 and a second sound absorption module 3 are sequentially arranged in the sound absorption pipeline 1 along the flow direction, the first sound absorption module 2 comprises a first perforated plate 21, the first perforated plate 21 is used for absorbing noise in a first frequency range, the second sound absorption module 3 comprises a second perforated plate 31 and a third perforated plate 32, the third perforated plate 32 is arranged at the radial outer side of the second perforated plate 31, and the third perforated plate 32 and the second perforated plate 31 are used for absorbing noise in a second frequency range.

[0043] In this embodiment, the noise reduction device can absorb noise in the first frequency range and the second frequency range respectively by arranging the first sound absorption module 2 and the second sound absorption module 3, so as to continuously process the high-energy noise generated by the rotation of the centrifugal compressor impeller at the blade passing frequency of one and two times during the propagation process, thereby reducing the noise intensity radiated outward by the centrifugal compressor and reducing the noise pollution to the surrounding environment and the on-site workers during the operation of the centrifugal compressor.

[0044] Among them, the sound absorption pipeline 1 is the basic structure of the whole noise reduction device, which provides a specific space for noise processing. Specifically, the first sound absorption module 2 and the second sound absorption module 3 can be arranged in the sound absorption pipeline 1 to realize the noise reduction function. In actual application, the noise will fully contact the first sound absorption module 2 and the second sound absorption module 3 inside the sound absorption pipeline 1 when passing through the sound absorption pipeline 1, so that the first sound absorption module 2 and the second sound absorption module 3 can effectively process the noise.

[0045] The first sound absorption module 2 includes a first perforated plate 21, the first perforated plate 21 is in a ring structure, and a plurality of first sound absorption holes 211 are distributed on the first perforated plate 21. In the noise reduction process, when the noise propagates in the form of sound waves to the first sound absorption module 2, the following phenomenon occurs: part of the sound waves will enter the space formed by the outer wall of the first perforated plate 21 and the inner wall of the sound absorption channel, and will undergo multiple reflections therein. It can be understood that during the reflection process, the energy form of the sound waves changes, and the sound energy is gradually converted into other forms of energy, such as heat energy. Thus, the effective absorption of noise in the first frequency range is achieved, thereby reducing the energy intensity of the noise in this frequency band during the entire propagation process and contributing to the overall noise reduction effect.

[0046] Specifically, the noise in the first frequency range can be high-energy noise generated by the rotation of the centrifugal compressor impeller at one blade passing frequency.

[0047] The second sound absorption module 3 includes a second perforated plate 31 and a third perforated plate 32, both of which are in a ring structure and are distributed radially. In this embodiment, the second perforated plate 31 has a plurality of second sound absorption holes 311, and the third perforated plate 32 has a plurality of third sound absorption holes 321. The third perforated plate 32 is located radially outside the second perforated plate 31. In the noise reduction process, when the noise propagates in the form of sound waves to the second sound absorption module 3, it first interacts with the second perforated plate 31, and the sound absorption principle of the first perforated plate 21 is similar. The second perforated plate 31 will guide part of the sound waves into the second sound absorption holes 311. In this process, a part of the sound energy is absorbed through a series of physical processes such as air vibration, friction, and reflection. At this time, the third perforated plate 32 located radially outside the second perforated plate 31 can further improve the absorption capacity of the second frequency range noise. Specifically, the third perforated plate 32 can change the propagation path of the sound waves near the second perforated plate 31, so that the sound waves undergo multiple reflections and refractions between the second perforated plate 31 and the third perforated plate 32. Thus, the contact time and contact frequency of the sound waves with the second sound absorption module 3 are increased, thereby more comprehensively and sufficiently absorbing the noise in the second frequency range and effectively improving the absorption effect of the entire second sound absorption module 3 on the noise in this frequency range.

[0048] Specifically, the noise in the second frequency range can be high-energy noise generated by the rotation of the centrifugal compressor impeller at two blade passing frequencies.

[0049] It should be noted that in the present embodiment, the first sound absorption module 2 is a single layer of the first perforated plate 21, and the principle of absorbing noise is based on the energy conversion of sound waves after multiple reflections between the outer wall of the first perforated plate 21 and the inner wall of the sound absorption channel. Such a structure is more effective for absorbing lower frequency noise, because the wavelength of low frequency noise is longer, and there is enough space and time for reflection and other energy conversion processes in a relatively simple structure. The second sound absorption module 3 is a double-layer structure composed of the second perforated plate 31 and the third perforated plate 32, and is distributed radially. Such a double-layer structure can change the propagation path of sound waves, so that sound waves are reflected and refracted multiple times between the second and third perforated plates 32. Because the wavelength of high frequency noise is shorter, it is easier to interact with the above structure in such a double-layer structure. For example, high frequency sound waves can be reflected multiple times in a short distance between the double-layer perforated plates, increasing the opportunity for sound energy loss, which is beneficial to absorbing high frequency noise.

[0050] In some possible implemented embodiments disclosed in the present application, the thickness of the first perforated plate 21 is 0.5mm-1.5mm, and the perforation rate of the first perforated plate 21 is 3%-15%; the thickness of the second perforated plate 31 is 1mm-2.5mm, and the perforation rate of the second perforated plate 31 is 3%-15%; the thickness of the third perforated plate 32 is 0.5mm-1.5mm, and the perforation rate of the third perforated plate 32 is 1%-5%.

[0051] In the present embodiment, the thickness of the first perforated plate 21 is 0.5mm-1.5mm. It should be noted that a thinner first perforated plate 21 (such as 0.5mm) is better for absorbing low frequency noise. Because the wavelength of low frequency noise is longer, the vibration of a thinner first perforated plate 21 under the action of sound waves is relatively easier, which can better couple with low frequency sound waves, thereby effectively absorbing low frequency noise.

[0052] Specifically, the perforation rate of the first perforated plate 21 is 3%-15%. A lower perforation rate (such as 3%) means that there are relatively fewer first sound absorption holes 211 on the first perforated plate 21. In this case, when sound waves reach the first perforated plate 21, the proportion of sound waves entering the first sound absorption holes 211 is smaller, and more sound waves will be reflected on the outer wall of the first perforated plate 21. This is more conducive to absorbing low frequency noise, because the energy of low frequency noise is mainly concentrated in a larger spatial range, and fewer first sound absorption holes 211 can make the sound waves have more sufficient reflection between the outer wall of the first perforated plate 21 and the inner wall of the sound absorption channel, thereby converting the sound energy into other forms of energy.

[0053] The thickness of the second perforated plate 31 is between 1mm and 2.5mm. It is to be noted that the relatively thick range makes the second perforated plate 31 more advantageous for absorbing noise of higher frequencies. High frequency noise has shorter wavelength, and the thicker second perforated plate 31 can provide more reflection interfaces. When high frequency sound waves enter the second sound absorption hole 311, they will experience more reflection and refraction on the thicker second perforated plate 31, increasing the loss of sound energy. Moreover, the thicker second perforated plate 31, when cooperating with the third perforated plate 32, can better control the propagation path of sound waves between the two, which is advantageous for absorbing high frequency noise.

[0054] Specifically, the perforation rate of the second perforated plate 31 is also between 3% and 15%. For the second perforated plate 31, it is mainly used to absorb higher frequency noise. A lower perforation rate (3%) can make the high frequency sound waves entering the second sound absorption hole 311 have stronger reflection and vibration within the second sound absorption hole 311, because relatively fewer second sound absorption holes 311 can make the air in each second sound absorption hole 311 vibrate more violently, thereby increasing the loss of sound energy.

[0055] The thickness of the third perforated plate 32 is 0.5mm to 1.5mm. It is to be noted that the third perforated plate 32 of this thickness range can work in cooperation with the second perforated plate 31 without affecting the compactness of the overall structure of the noise reduction device. The thinner part (0.5mm) can produce a sensitive response to high frequency noise, because its mass is relatively light and it is easy to vibrate under the action of high frequency sound waves, thereby increasing the loss of sound energy.

[0056] Specifically, the perforation rate of the third perforated plate 32 is 1% to 5%. A lower perforation rate makes the third perforated plate 32 mainly serve to change the propagation path of sound waves. Fewer third sound absorption holes 321 can guide sound waves to reflect and refract multiple times in the space between the second perforated plate 31 and the third perforated plate 32, rather than a large number of sound waves passing directly through the third sound absorption hole 321. In this way, the space between the double-layer perforated plates can be fully utilized to absorb high frequency noise, enhancing the absorption capacity of the second sound absorption module 3 for noise in the second frequency range.

[0057] In some possible implementation embodiments disclosed in the present application, the diameter of the first sound absorption hole 211 is 1mm to 2.5mm, and the spacing distance between two adjacent first sound absorption holes 211 is 11mm; the diameter of the second sound absorption hole 311 is 1mm to 2.5mm, and the spacing distance between two adjacent second sound absorption holes 311 is 12mm; the diameter of the third sound absorption hole 321 is 0.5mm to 1.5mm, and the spacing distance between two adjacent third sound absorption holes 321 is 13mm.

[0058] The diameter of the first sound absorption hole 211 is between 1 mm and 2.5 mm. When the sound wave enters the first sound absorption hole 211 with a small diameter, it will cause the air inside the first sound absorption hole 211 to vibrate violently. High-frequency noise is more likely to resonate with the air column in such a small space, thereby converting sound energy into heat energy or other forms of energy.

[0059] Specifically, the interval between two adjacent first sound absorption holes 211 is 11 mm. The sound absorption performance of the first perforated plate 21 can be controlled to ensure that the sound wave has a suitable reflection and propagation path between the outer wall of the first perforated plate 21 and the inner wall of the sound absorption channel when absorbing noise in the first frequency range. If the interval is too small, the sound waves between adjacent first sound absorption holes 211 may interfere with each other, affecting the sound absorption effect; if the interval is too large, it may reduce the opportunity for sound waves to enter the first sound absorption hole 211, reducing the sound absorption efficiency.

[0060] The diameter of the second sound absorption hole 311 is also between 1 mm and 2.5 mm. For absorbing noise in the second frequency range (relatively high frequency), the second sound absorption hole 311 with a smaller diameter (1 mm) can enhance the absorption of high-frequency components. After the high-frequency sound wave enters the second sound absorption hole 311, it will produce complex reflection and vibration inside the second sound absorption hole 311, increasing the loss of sound energy.

[0061] Specifically, the interval between two adjacent second sound absorption holes 311 is 12 mm. For the second perforated plate 31 to absorb noise in the second frequency range, this interval distance can optimize the propagation of high-frequency sound waves on the second perforated plate 31. Compared to the interval of the first sound absorption hole 211, the slightly larger interval distance allows the high-frequency sound wave to have more space to reflect and propagate on the surface of the second perforated plate 31, better interacting with the second sound absorption hole 311, thereby more effectively absorbing high-frequency noise.

[0062] The diameter of the third sound absorption hole 321 is between 0.5 mm and 1.5 mm. The smaller diameter range makes the third sound absorption hole 321 more targeted for absorbing high-frequency noise. After the high-frequency sound wave enters the third sound absorption hole 321, the vibration of the air column is more violent due to the smaller space of the third sound absorption hole 321, and the loss of sound energy is more obvious. The third sound absorption hole 321 with such a small diameter, combined with the lower perforation rate of the third perforated plate 32, can effectively guide the high-frequency sound wave to reflect and refract multiple times in the space between the second perforated plate 31 and the third perforated plate 32, enhancing the absorption effect of high-frequency noise.

[0063] Specifically, the two third sound absorption holes 321 adjacent to each other are spaced apart by 13 mm. Such a relatively large spacing distance can make the third perforated plate 32 better play its role of changing the sound wave propagation path. Under the premise of ensuring a certain density of the third sound absorption holes 321, the larger spacing distance can guide the high-frequency sound waves to be more fully reflected and refracted in the space between the second perforated plate 31 and the third perforated plate 32, avoiding the sound waves from passing through the third sound absorption holes 321 too concentratedly, thereby enhancing the absorption effect of the high-frequency noise in the second frequency range.

[0064] In the above embodiments, referring to Figs. Figure 3 、 Figure 7 and Figure 9 , the plurality of first sound absorption holes 211, the plurality of second sound absorption holes 311 and the plurality of third sound absorption holes 321 are in equilateral triangle distribution.

[0065] In this embodiment, when the first sound absorption holes 211, the second sound absorption holes 311 and the third sound absorption holes 321 are in equilateral triangle distribution, a more uniform sound absorption hole layout can be achieved on the perforated plate. For the first sound absorption holes 211, such uniform distribution makes the first perforated plate 21, when absorbing the noise in the first frequency range, be able to enter the first sound absorption holes 211 more uniformly regardless of the direction from which the sound waves come. It will not appear the situation that some areas are over-absorbed and some areas are under-absorbed due to the uneven distribution of the first sound absorption holes 211, thereby ensuring the uniformity and stability of the first perforated plate 21 in absorbing the noise in the first frequency range. Similarly, for the second sound absorption holes 311 and the third sound absorption holes 321, the second perforated plate 31 and the third perforated plate 32 can also provide uniform sound absorption capability on the entire second perforated plate 31 and the second perforated plate 31 when absorbing the noise in the second frequency range. Especially for high-frequency noise, the uniformly distributed second sound absorption holes 311 and the third sound absorption holes 321 can more effectively capture high-frequency sound waves from different directions, ensuring that the high-frequency noise can be effectively processed in the entire second sound absorption module 3.

[0066] When the sound absorption holes are in equilateral triangle distribution, each sound absorption hole is surrounded by six adjacent sound absorption holes, and the distance between them is equal from the geometric point of view. Taking the first sound absorption hole 211 as an example, on the first perforated plate 21, such a distribution forms a regular and repeated pattern. The vertex of each equilateral triangle is the position of a first sound absorption hole 211. Such a layout makes the first sound absorption holes 211 very evenly distributed on the first perforated plate 21. The same is true for the second sound absorption holes 311 and the third sound absorption holes 321. On the second perforated plate 31 and the third perforated plate 32, such an equilateral triangle distribution ensures that the spatial positions of the sound absorption holes on the respective perforated plates have high symmetry. For example, when observing a local area, the distribution density and relative position relationship of the sound absorption holes are the same from any direction.

[0067] In some possible implementation embodiments disclosed in the present application, referring to Figure 1 As shown in the figure, the first sound absorption module 2 further comprises a first honeycomb core 22 and an annular back plate 23. The first honeycomb core 22 is arranged radially outside the first perforated plate 21, and the annular back plate 23 is arranged between the outer wall of the first honeycomb core 22 and the inner wall of the sound absorption duct 1.

[0068] In this embodiment, the first honeycomb core 22 provides an additional propagation path and energy loss mechanism for sound waves. When sound waves act on the first sound absorption module 2, part of the sound waves will enter the first honeycomb core 22 after passing through the first perforated plate 21. The first honeycomb core 22 is a honeycomb structure with limited internal space and complex shape. In this case, the sound waves entering it will continuously reflect back and forth in this honeycomb structure, and the energy of the sound waves will continue to decrease, thereby achieving the sound absorption effect. Further, the radial outer side of the first honeycomb core 22 is provided with an annular back plate 23. When the sound waves propagate outward after reflecting in the first honeycomb core 22, the annular back plate 23 will reflect the sound waves back into the honeycomb core, so that the sound waves are reflected and energy is lost between the honeycomb core and the annular back plate 23 again. Thus, the propagation path of the sound waves in the first sound absorption module 2 can be prolonged, the contact time of the sound waves with the sound absorption structure can be increased, and the absorption efficiency of the noise in the first frequency range can be further improved.

[0069] In this embodiment, the first honeycomb core 22 is an annular structure. In actual application, the first perforated plate 21, the first honeycomb core 22 and the annular back plate 23 are distributed radially.

[0070] Specifically, the first honeycomb core 22 is located radially outside the first perforated plate 21, and the annular back plate 23 is located outside the first honeycomb core 22. In this structure, the first perforated plate 21, the first honeycomb core 22, and the annular back plate 23 are connected into one whole by full brazing, which improves the overall strength of the first sound absorption module 2 and can meet the requirements of long-term safe and stable operation, while avoiding the aging problem of the noise reduction device using the first sound absorption module 2 for a long time.

[0071] In the above embodiment, referring to Figure 5 As shown in the figure, the thickness of the first honeycomb core 22 is 11mm-61mm, and the basic unit shape of the first honeycomb core 22 is a regular hexagon.

[0072] Wherein, the basic unit of the first honeycomb core 22 is the smallest repeating unit that constitutes the first honeycomb core 22. In this embodiment, by setting the basic unit of the first honeycomb core 22 as a regular hexagon, the space of the first honeycomb core 22 can be maximally utilized to provide more reflection and propagation interfaces for sound waves. It should be noted that compared with other shapes (such as square or triangle) of basic units, the regular hexagonal basic unit can provide more wall area for sound wave reflection under the same area, thereby improving the sound absorption efficiency.

[0073] In some possible implemented embodiments disclosed in the present application, referring to Figure 1 As shown in the figure, the second sound absorption module 3 further includes a second honeycomb core 33 and an annular rib plate 34, the second honeycomb core 33 is arranged between the second perforated plate 31 and the third perforated plate 32, and the annular rib plate 34 is arranged between the outer wall of the third perforated plate 32 and the inner wall of the sound absorption duct 1.

[0074] In this embodiment, the structure of the second honeycomb core 33 is similar to that of the first honeycomb core 22. When the sound wave enters the second honeycomb core 33 after passing through the second perforated plate 31, due to the complex space shape inside the second honeycomb core 33, the sound wave will frequently collide with the wall in the second honeycomb core 33, and each collision will convert part of the sound energy into heat energy, thereby effectively attenuating the sound energy and enhancing the absorption effect of the second sound absorption module 3 on high-frequency noise.

[0075] Wherein, the second honeycomb core 33 is also an annular structure. In actual application, the second perforated plate 31, the second honeycomb core 33, the third perforated plate 32, and the annular rib plate 34 are distributed radially.

[0076] Specifically, the second honeycomb core 33 is located radially outside the second perforated plate 31, the third perforated plate 32 is located radially outside the second honeycomb core 33, and the annular rib plate 34 is located radially outside the third perforated plate 32. In this embodiment, multiple annular rib plates 34 can be provided, and the multiple annular rib plates 34 are arranged at intervals in the axial direction. By providing the annular rib plate 34, the second honeycomb core 33 and the third perforated plate 32 can be supported, and the stability of the acoustic relationship of the second sound absorption module 3 can be ensured. In addition, it should be noted that in this structure, the second perforated plate 31, the second honeycomb core 33, the third perforated plate 32, and the annular rib plate 34 are fully brazed to form a whole, which improves the overall strength of the second sound absorption module 3 and can meet the requirements of long-term safe and stable operation, and can also avoid the aging problem of the second sound absorption module 3 of the noise reduction device after long-term use.

[0077] In the above embodiment, referring to Figure 11 It is shown that the basic unit shape of the second honeycomb core 33 is also a regular hexagon, and the thickness of the second honeycomb core 33 and the annular rib plate 34 is 5mm-30mm.

[0078] Among them, the basic unit of the second honeycomb core 33 is the smallest repeating unit that constitutes the second honeycomb core 33. In this embodiment, by setting the basic unit of the second honeycomb core 33 as a regular hexagon, the space of the second honeycomb core 33 can be utilized to the maximum, and more reflection and propagation interfaces for sound waves can be provided. It should be noted that compared with other shapes (such as square or triangle) of the basic unit, the regular hexagonal basic unit can provide more wall area for sound wave reflection under the same area, thereby improving the sound absorption efficiency.

[0079] In some possible implemented embodiments disclosed in the present application, referring to Figure 1 It is shown that the noise reduction device further comprises a butt flange, and the butt flange is arranged at the end of the sound absorption pipeline 1.

[0080] In this embodiment, the butt flange provides convenience for the connection between the sound absorption pipeline 1 and the inlet and outlet pipes of the centrifugal compressor.

[0081] Among them, during the installation process, the butt flange and the corresponding flange of the inlet and outlet pipes can be connected through bolts and other connecting members, which is simple and fast. Moreover, when the noise reduction device needs to be repaired, replaced or modified, this flange connection method makes the noise reduction device can be easily detached from the inlet and outlet pipes, which improves the work efficiency.

[0082] It is easy for those skilled in the art to understand that the above advantageous modes can be freely combined and superimposed without conflict.

[0083] The above merely preferred embodiments of the present application are not used to limit the present application, any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application. The above is merely the preferred embodiment of the present application, it should be pointed out that, for the ordinary skilled in the art, without departing from the technical principle of the present application, a number of improvements and variations can be made, these improvements and variations should also be considered as the protection scope of the present application.

Claims

1. A noise reduction device, characterized in that, The system includes a sound-absorbing duct (1), in which a first sound-absorbing module (2) and a second sound-absorbing module (3) are sequentially arranged along the flow direction. The first sound-absorbing module (2) includes a first perforated plate (21), which is used to absorb noise in a first frequency range. The second sound-absorbing module (3) includes a second perforated plate (31) and a third perforated plate (32), which is arranged on the radial outer side of the second perforated plate (31). The third perforated plate (32) and the second perforated plate (31) are used to absorb noise in a second frequency range. The first sound-absorbing module (2) further includes a first honeycomb core (22) and an annular back plate (23). The first honeycomb core (22) is disposed on the radial outer side of the first perforated plate (21), and the annular back plate (23) is disposed between the outer wall of the first honeycomb core (22) and the inner wall of the sound-absorbing pipe (1). The second sound-absorbing module (3) further includes a second honeycomb core (33) and an annular rib plate (34). The second honeycomb core (33) is disposed between the second perforated plate (31) and the third perforated plate (32). The annular rib plate (34) is disposed between the outer wall of the third perforated plate (32) and the inner wall of the sound-absorbing pipe (1).

2. The noise reduction device according to claim 1, characterized in that, The thickness of the first perforated plate (21) is 0.5mm~1.5mm, and the perforation rate of the first perforated plate (21) is 3%~15%; The thickness of the second perforated plate (31) is 1mm to 2.5mm, and the perforation rate of the second perforated plate (31) is 3% to 15%. The thickness of the third perforated plate (32) is 0.5mm to 1.5mm, and the perforation rate of the third perforated plate (32) is 1% to 5%.

3. The noise reduction device according to claim 1, characterized in that, The first perforated plate (21) is provided with a plurality of first sound-absorbing holes (211), the diameter of the first sound-absorbing hole (211) is 1mm~2.5mm, and the interval between two adjacent first sound-absorbing holes (211) is 11mm; The second perforated plate (31) is provided with a plurality of second sound-absorbing holes (311), the diameter of the second sound-absorbing hole (311) is 1mm~2.5mm, and the interval between two adjacent second sound-absorbing holes (311) is 12mm; The third perforated plate (32) is provided with a plurality of third sound-absorbing holes (321), the diameter of the third sound-absorbing hole (321) is 0.5mm~1.5mm, and the interval between two adjacent third sound-absorbing holes (321) is 13mm.

4. The noise reduction device according to claim 3, characterized in that, The first sound-absorbing holes (211), the second sound-absorbing holes (311), and the third sound-absorbing holes (321) are all arranged in an equilateral triangle.

5. The noise reduction device according to claim 1, characterized in that, The thickness of the first honeycomb core (22) is 11mm~61mm, and the basic unit shape of the first honeycomb core (22) is a regular hexagon.

6. The noise reduction device according to claim 1, characterized in that, The basic unit shape of the second honeycomb core (33) is also a regular hexagon, and the thickness of the second honeycomb core (33) and the annular stiffener (34) is 5mm~30mm.

7. The noise reduction device according to claim 1, characterized in that, It also includes a docking flange, which is disposed at the end of the sound-absorbing pipe (1).

8. A centrifugal compressor, characterized in that, Includes the noise reduction device as described in any one of claims 1-7.

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