CN113954890B - Noise reduction floor for railway vehicle - Google Patents
Noise reduction floor for railway vehicle Download PDFInfo
- Publication number
- CN113954890B CN113954890B CN202111329986.3A CN202111329986A CN113954890B CN 113954890 B CN113954890 B CN 113954890B CN 202111329986 A CN202111329986 A CN 202111329986A CN 113954890 B CN113954890 B CN 113954890B
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- CN
- China
- Prior art keywords
- corrugated plate
- upper panel
- sound absorbing
- noise reduction
- cavities
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61D—BODY DETAILS OR KINDS OF RAILWAY VEHICLES
- B61D17/00—Construction details of vehicle bodies
- B61D17/04—Construction details of vehicle bodies with bodies of metal; with composite, e.g. metal and wood body structures
- B61D17/10—Floors
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/162—Selection of materials
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T30/00—Transportation of goods or passengers via railways, e.g. energy recovery or reducing air resistance
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Life Sciences & Earth Sciences (AREA)
- Wood Science & Technology (AREA)
- Mechanical Engineering (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Abstract
The invention discloses a noise reduction floor of a railway vehicle, which comprises the following components: the upper panel, the lower panel and the corrugated plate are provided with micropores; the upper panel, the corrugated plate and the lower panel are sequentially and fixedly connected from top to bottom, the upper panel is connected with the corrugated plate to form a plurality of trough cavities, the lower panel is connected with the corrugated plate to form a plurality of wave crest cavities, and the trough cavities and the wave crest cavities are respectively filled with sound absorbing materials with different acoustic impedance characteristics and used for absorbing or isolating high-frequency noise. The invention has the advantages of compact structure, simple manufacture, high mechanical strength, excellent sound insulation and sound absorption performance and the like.
Description
Technical Field
The invention belongs to the technical field of noise reduction of rail train bodies, and particularly relates to a noise reduction floor for a rail train.
Background
Today, with the continuous increase of the running speed of high-speed trains, the problem of train noise is also increasing, which not only affects the riding comfort of people, but also causes the passengers with annoyance feeling, tired feeling, and even damages to the hearing of people when the passengers are in the noise for a long time. Meanwhile, long-time noise has no small threat to the health of train drivers and passengers, and the train drivers and passengers can be tired rapidly and even influence the normal operation of the train, so that the control of the noise in the high-speed train is an urgent problem to be solved.
At present, in order to realize the light weight of the vehicle body structure, the main measure is to replace the built-in floor with a corrugated plate, which consists of an upper plate, a lower plate and a middle corrugated plate. The sandwich structure of the corrugated board enables the stress of the panel to be evenly dispersed, and the structure is prevented from generating concentrated load. It has good rigidity, and its thickness is thin but can bear the weight of car body. But the corrugated board structure has higher rigidity, light weight and poorer sound insulation effect on the noise of the bottom wheel track. The panels of the corrugated boards are made of compact metal materials, and the sound absorption effect on noise in the vehicle is extremely poor.
Disclosure of Invention
The invention aims to overcome the defect of poor sound insulation and sound absorption performance of the built-in floor of the railway vehicle in the prior art, and provides the noise reduction floor of the railway vehicle, which has the advantages of compact structure, simple manufacture, high mechanical strength and excellent sound insulation and sound absorption performance.
In order to solve the technical problems, the invention adopts the following technical scheme:
a railway vehicle noise reduction floor comprising: the upper panel, the lower panel and the corrugated plate are provided with micropores; the upper panel, the corrugated plate and the lower panel are sequentially and fixedly connected from top to bottom, the upper panel is connected with the corrugated plate to form a plurality of trough cavities, the lower panel is connected with the corrugated plate to form a plurality of wave crest cavities, and the trough cavities and the wave crest cavities are respectively filled with sound absorbing materials with different acoustic impedance characteristics and used for absorbing or isolating high-frequency noise.
As a further improvement of the invention, air separation layers with adjustable thickness are arranged between the sound absorption material and the trough cavity and between the sound absorption material and the wave crest cavity, so that a series resonance sound absorption structure is formed among the sound absorption material, the upper panel and the corrugated plate and is used for absorbing low-frequency noise.
As a further improvement of the invention, a plurality of first micropores are uniformly distributed on the upper panel, and the diameters of the first micropores are 1-3 mm.
As a further improvement of the invention, second micropores are symmetrically arranged on two sides of the wave crest of the corrugated plate, and the diameter of each second micropore is 0.5-2.5 mm.
As a further improvement of the present invention, the diameter of the first micropores is greater than or equal to the diameter of the second micropores.
As a further improvement of the invention, the filling height of the sound absorbing material in the trough cavities and the crest cavities is lower than or equal to the setting height of the second micropores on the corrugated plate.
As a further development of the invention, the sound absorbing material is melamine or rock wool or rubber damping material.
As a further improvement of the present invention, the upper and lower panels are made of a metal material.
As a further improvement of the invention, the upper panel, the corrugated plate and the lower panel are fixedly connected by adopting a welding mode.
As a further improvement of the invention, the upper and lower panels are made of nonmetallic composite materials.
As a further improvement of the invention, the upper panel, the corrugated plate and the lower panel are fixedly connected by adopting an adhesive mode.
Compared with the prior art, the invention has the advantages that:
according to the noise reduction floor for the railway vehicle, the micropores are formed in the upper panel and the corrugated plate, and the sound absorption materials with different acoustic impedance characteristics are filled in the trough cavity formed by connecting the upper panel and the corrugated plate and the wave crest cavity formed by connecting the lower panel and the corrugated plate respectively, so that the high-frequency noise is effectively absorbed or isolated; meanwhile, the crest bilateral symmetry of buckled plate is equipped with the second micropore for trough cavity and crest cavity intercommunication each other to all there is thickness adjustable air interlayer between sound absorbing material and trough cavity and the crest cavity, has reserved the air bed of certain thickness between sound absorbing material and top panel and the bellows promptly, has made to constitute series resonance sound absorbing structure between sound absorbing material and top panel and the buckled plate, has realized the noise absorption of lower frequency and wider frequency band. Further, the sizes and arrangement positions of the micropore apertures on the upper panel and the corrugated plates and the sizes of the cavities of the series resonance sound absorption structures are all related to the frequency of main noise in the railway vehicle, and the sizes of the cavities of the series resonance sound absorption structures can be adjusted by changing the filling volumes of sound absorption materials in the cavities of all the troughs and the cavities of all the peaks, so that series combination of different cavities is formed, diversified sound absorption structures are obtained in the noise reduction floor, the characteristics of the acoustic noise reduction materials and the resonance structures are combined, the sound insulation and sound absorption performances of the noise reduction floor are remarkably improved, the noise reduction requirements of the railway vehicle are well met, and the riding comfort of the railway vehicle is improved.
Drawings
Fig. 1 is a schematic structural diagram of a noise reduction floor for a railway vehicle according to the present invention.
Fig. 2 is a schematic cross-sectional structural view of the noise reduction floor for a railway vehicle according to the present invention.
Fig. 3 is a schematic structural diagram of a corrugated board in a noise reduction floor of a railway vehicle according to the present invention.
Legend description: 1. an upper panel; 2. a lower panel; 3. corrugated plates; 4. a first sound absorbing material; 5. a second sound absorbing material; 6. a first microwell; 7. a trough cavity; 8. a second microwell; 9. a peak cavity.
Detailed Description
The invention is further described below in connection with the drawings and the specific preferred embodiments, but the scope of protection of the invention is not limited thereby.
Example 1
As shown in fig. 1 to 3, the noise reduction floor for a railway vehicle of the present invention includes: the corrugated plate comprises an upper panel 1, a lower panel 2 and a corrugated plate 3, wherein micropores are formed in the upper panel 1 and the corrugated plate 3, and the height of the corrugated plate 3 is 20-40 mm. The upper panel 1, the corrugated plate 3 and the lower panel 2 are sequentially and fixedly connected from top to bottom, the upper panel 1 is connected with the corrugated plate 3 to form a plurality of wave trough cavities 7, and the lower panel 2 is connected with the corrugated plate 3 to form a plurality of wave crest cavities 9. The trough cavity 7 is filled with the first sound absorbing material 4, the peak cavity 9 is filled with the second sound absorbing material 5, the first sound absorbing material 4 and the second sound absorbing material 5 respectively have different acoustic impedance characteristics, but porous sound absorbing materials can be adopted for absorbing or isolating high-frequency noise so as to realize noise reduction of the railway vehicle. It will be understood that in this embodiment, high frequency noise refers to noise having a frequency of 1000Hz to 3000Hz, and low frequency noise refers to noise having a frequency of 100Hz to 1000 Hz. It will be appreciated that the choice of the type of first sound absorbing material 4 and second sound absorbing material 5, and the location of the filling of both sound absorbing materials within the valley cavity 7 and peak cavity 9, is related to the frequency of the main noise of the vehicle. For example, a porous sound absorbing material with more excellent acoustic impedance characteristics can be selected at a part with higher noise frequency, and the filling quantity of the porous sound absorbing material in the trough cavity 7 and the crest cavity 9 is increased so as to improve the noise reduction effect; in the part with lower noise frequency, the performance requirement on the porous sound absorbing material can be reduced, and the filling amount of the porous sound absorbing material in the trough cavity 7 and the crest cavity 9 is correspondingly adjusted, so that the noise reduction requirement is met, and the manufacturing cost of the noise reduction floor is reduced. In the preparation process of the noise reduction floor, firstly, according to the filling requirements in each trough cavity 7 and each wave crest cavity 9, the porous sound absorption material is correspondingly cut, and then the cut porous sound absorption material is filled into the corresponding trough cavity 7 or wave crest cavity 9.
In this embodiment, air barriers with adjustable thickness are respectively arranged between the sound absorbing material and the trough cavity 7 and between the sound absorbing material and the crest cavity 9, so as to form a series resonance sound absorbing structure among the sound absorbing material, the upper panel 1 and the corrugated plate 3, and the series resonance sound absorbing structure is used for absorbing low-frequency noise. As shown in fig. 2, the filling heights of the first sound absorbing material 4 in the respective wave trough cavities 7 are not the same, the filling heights of the second sound absorbing material 5 in the wave crest cavities 9 are slightly different, and the wave trough cavities 7 or the wave crest cavities 9 are not completely filled with the sound absorbing material, so that a series resonance sound absorbing structure is formed among the sound absorbing material, the upper panel 1 and the corrugated plate 3, and low-frequency noise propagates in the series resonance sound absorbing structure and is absorbed. It can be understood that the filling height of the sound absorbing material in the trough cavity 7 or the peak cavity 9 can be adjusted according to the actual noise reduction requirement, so as to adjust the volume of the cavity of the series resonance sound absorbing structure and realize the absorption of noise with wider frequency band.
In this embodiment, a plurality of first micropores 6 are uniformly distributed on the upper panel 1, and the diameter of the first micropores 6 is 1mm to 3mm. Second micropores 8 are symmetrically arranged on two sides of the wave crest of the corrugated plate 3, and the diameter of each second micropore 8 is 0.5-2.5 mm. Further, the diameter of the first microwells 6 is 0.5mm larger than the diameter of the second microwells 8. According to the impedance matching principle, the aperture of the first micropore 6 serving as the front opening is larger than or equal to that of the second micropore 8 serving as the rear opening, so that the sound absorption peak value is improved, and the noise absorption effect is improved.
In this embodiment, the filling height of the first sound absorbing material 4 in the wave trough cavities 7 and the filling height of the second sound absorbing material 5 in the wave crest cavities 9 are lower than or equal to the setting height of the second micro holes 8 on the corrugated plate 3. So as to ensure that the trough cavities 7 and the crest cavities 9 are communicated with each other, so that a series resonance sound absorption structure is formed between the sound absorption material and the upper panel 1 and the corrugated plate 3, and the noise absorption of lower frequency and wider frequency range is realized.
In this embodiment, melamine, rock wool or rubber damping material may be used as the sound absorbing material. Further, the first sound absorbing material 4 is made of melamine material, and the second sound absorbing material 5 is made of rock wool material. The first sound absorbing material 4 and the second sound absorbing material 5 are respectively made of materials with different acoustic impedance characteristics so as to be favorable for better absorbing or isolating high-frequency noise.
In this embodiment, the upper panel 1, the lower panel 2 and the corrugated plate 3 are made of metal materials, such as aluminum alloy materials, and have the characteristics of high mechanical strength, corrosion resistance, excellent welding performance and the like. Correspondingly, the upper panel 1, the corrugated plate 3 and the lower panel 2 are fixedly connected in a welding mode.
It will be appreciated that in other embodiments, the upper panel 1, the lower panel 2 and the corrugated plate 3 may be made of non-metal composite materials, such as carbon fiber composite materials, which have excellent mechanical properties, and not only retain the inherent characteristics of carbon materials, but also have soft processability of textile fibers, thereby realizing the lightweight design of the noise reduction floor. Correspondingly, the upper panel 1, the corrugated plate 3 and the lower panel 2 are fixedly connected in an adhesive manner.
In this embodiment, the micropores are formed on the upper panel 1 and the corrugated pipe 3, and the first sound absorbing material and the second sound absorbing material with different acoustic impedance characteristics are respectively filled in the trough cavity 7 formed by connecting the upper panel 1 and the corrugated plate 3 and the peak cavity 9 formed by connecting the lower panel 2 and the corrugated plate 3, so that the absorption or isolation of high-frequency noise is effectively realized. Meanwhile, the crest bilateral symmetry of buckled plate 3 is equipped with second micropore 8 for trough cavity 7 and crest cavity 9 each other UNICOM, and all there is thickness adjustable air interlayer between sound absorbing material and trough cavity 7 and the crest cavity 9, has also reserved the air bed of certain thickness between sound absorbing material and top panel 1 and the bellows 3, has made to constitute series resonance sound absorbing structure between sound absorbing material and top panel 1 and the buckled plate 3, has realized the noise absorption of lower frequency and wider frequency band. Further, the sizes and arrangement positions of the micropore apertures on the upper panel 1 and the corrugated plate 3 and the sizes of the cavities of the series resonance sound absorption structures are all related to the frequency of main noise in the railway vehicle, and the sizes of the cavities of the series resonance sound absorption structures can be adjusted by changing the filling volumes of sound absorption materials in each trough cavity 7 and each crest cavity 9, so that series combination of different cavities is formed, diversified sound absorption structures are obtained in the noise reduction floor, the characteristics of the acoustic noise reduction materials and the resonance structures are combined, the sound insulation and sound absorption performances of the noise reduction floor are remarkably improved, and the noise reduction requirements of the railway vehicle are well met.
While the invention has been described in terms of preferred embodiments, it is not intended to be limiting. Any person skilled in the art can make many possible variations and modifications to the technical solution of the present invention or equivalent embodiments using the method and technical solution disclosed above without departing from the spirit and technical solution of the present invention. Therefore, any simple modification, equivalent substitution, equivalent variation and modification of the above embodiments according to the technical substance of the present invention, which do not depart from the technical solution of the present invention, still fall within the scope of the technical solution of the present invention.
Claims (6)
1. A railway vehicle noise reduction floor, comprising: the corrugated plate comprises an upper panel (1), a lower panel (2) and a corrugated plate (3), wherein micropores are formed in the upper panel (1) and the corrugated plate (3); the upper panel (1), the corrugated plate (3) and the lower panel (2) are sequentially and fixedly connected from top to bottom, the upper panel (1) is connected with the corrugated plate (3) to form a plurality of wave trough cavities (7), the lower panel (2) is connected with the corrugated plate (3) to form a plurality of wave crest cavities (9), and the wave trough cavities (7) and the wave crest cavities (9) are respectively filled with sound absorbing materials with different acoustic impedance characteristics and are used for absorbing or isolating high-frequency noise; an air interlayer with adjustable thickness is arranged between the sound absorbing material and the trough cavity (7) and between the sound absorbing material and the crest cavity (9), so that a series resonance sound absorbing structure is formed among the sound absorbing material, the upper panel (1) and the corrugated plate (3) and is used for absorbing low-frequency noise;
a plurality of first micropores (6) are uniformly distributed on the upper panel (1), and the diameters of the first micropores (6) are 1-3 mm;
second micropores (8) are symmetrically arranged on two sides of a wave crest of the corrugated plate (3), and the diameter of each second micropore (8) is 0.5-2.5 mm;
the diameter of the first micropores (6) is larger than or equal to that of the second micropores (8);
the filling height of the sound absorbing material in the trough cavity (7) and the crest cavity (9) is lower than or equal to the setting height of the second micropore (8) on the corrugated plate (3).
2. The railway vehicle noise reduction floor according to claim 1, wherein the sound absorbing material is melamine or rock wool or rubber damping material.
3. The noise reduction floor for rail vehicles according to claim 1, characterized in that the upper panel (1), the lower panel (2) and the corrugated plate (3) are all made of metal materials.
4. A railway vehicle noise reduction floor according to claim 3, characterized in that the upper panel (1), the corrugated plate (3) and the lower panel (2) are fixedly connected by welding.
5. The noise reduction floor for rail vehicles according to claim 1, characterized in that the upper panel (1), the lower panel (2) and the corrugated plate (3) are all made of nonmetallic composite materials.
6. The noise reduction floor for railway vehicles according to claim 5, characterized in that the upper panel (1), the corrugated plate (3) and the lower panel (2) are fixedly connected by adopting an adhesive mode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111329986.3A CN113954890B (en) | 2021-11-10 | 2021-11-10 | Noise reduction floor for railway vehicle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111329986.3A CN113954890B (en) | 2021-11-10 | 2021-11-10 | Noise reduction floor for railway vehicle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113954890A CN113954890A (en) | 2022-01-21 |
| CN113954890B true CN113954890B (en) | 2023-08-01 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202111329986.3A Active CN113954890B (en) | 2021-11-10 | 2021-11-10 | Noise reduction floor for railway vehicle |
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Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001151107A (en) * | 1999-09-14 | 2001-06-05 | Tokai Rubber Ind Ltd | Soundproof construction of railway rolling stock |
| CN1807761A (en) * | 2006-02-16 | 2006-07-26 | 上海交通大学 | Microporous foam double-side absorbing sound type ultra-thin barrier |
| US8347575B2 (en) * | 2010-09-02 | 2013-01-08 | United States Gypsum Company | Lightweight acoustical flooring underlayment |
| CN102298925A (en) * | 2011-09-08 | 2011-12-28 | 周国柱 | Composite sound-absorbing structure |
| CN205075423U (en) * | 2015-10-16 | 2016-03-09 | 江苏苏通碳纤维有限公司 | Compound sound absorbing structure of microperforated panel - activated carbon fiber |
| CN107379646A (en) * | 2017-07-17 | 2017-11-24 | 西安交通大学 | A kind of porous material perforation ripple composite light multifunction clips laminate and preparation method |
| CN107558622A (en) * | 2017-08-03 | 2018-01-09 | 国网江西省电力公司电力科学研究院 | A kind of noise reduction sound insulation composite plate |
| CN109605842B (en) * | 2018-10-25 | 2022-10-21 | 中国船舶重工集团公司第七一九研究所 | Marine broadband multilayer composite sound absorption structure |
| CN109356297A (en) * | 2018-11-06 | 2019-02-19 | 株洲国创轨道科技有限公司 | Sound absorber |
| CN211616866U (en) * | 2019-12-27 | 2020-10-02 | 广东电网有限责任公司电力科学研究院 | Corrugated sandwich plate with periodic reinforced composite structure |
| CN213038228U (en) * | 2020-07-08 | 2021-04-23 | 北京市高速公路交通工程有限公司 | Sound absorbing element barrier for wide-tone noise |
| CN112477894A (en) * | 2020-12-09 | 2021-03-12 | 中车青岛四方机车车辆股份有限公司 | Noise reduction structure and noise reduction design method for aluminum alloy section of vehicle body and vehicle body |
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2021
- 2021-11-10 CN CN202111329986.3A patent/CN113954890B/en active Active
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