CN108859594B - High-speed railway train wheel bump leveller based on phononic crystal - Google Patents
High-speed railway train wheel bump leveller based on phononic crystal Download PDFInfo
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- CN108859594B CN108859594B CN201810387051.2A CN201810387051A CN108859594B CN 108859594 B CN108859594 B CN 108859594B CN 201810387051 A CN201810387051 A CN 201810387051A CN 108859594 B CN108859594 B CN 108859594B
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- cover plate
- vibration
- photonic crystal
- speed railway
- phononic crystal
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
- B60B17/00—Wheels characterised by rail-engaging elements
- B60B17/0006—Construction of wheel bodies, e.g. disc wheels
- B60B17/0024—Construction of wheel bodies, e.g. disc wheels with noise reducing means
Abstract
The invention aims to provide a phononic crystal-based high-speed railway train wheel vibration absorber, which comprises: the point defect localized photonic crystal vibration absorption device comprises an upper cover plate, a lower cover plate, a point defect localized photonic crystal vibration absorption component and a Bragg type photonic crystal vibration absorption component, wherein the Bragg type photonic crystal vibration absorption component is arranged in a space formed by the upper cover plate, the lower cover plate and the point defect localized photonic crystal vibration absorption component. The invention has simple integral structure and convenient manufacture, has good vibration and noise reduction effect on the high-speed railway train wheel in a medium-high frequency domain, has lower requirement on the working environment, and can be used for reducing the noise of the high-speed railway train wheel, improving the noise and vibration characteristics of the high-speed railway train wheel, improving the working environment of workers and the like.
Description
Technical Field
The invention relates to a vibration absorber, belongs to the technical field of vibration and noise reduction, and particularly relates to a high-speed railway train wheel vibration absorber based on a photonic crystal.
Background
In the prior art vibration control measures, vibration isolation is the most widely used technique, and it must be noted that vibrations cannot be completely eliminated, and can only be attenuated by techniques such as vibration isolation until the effect of the vibrations is within our permitted range.
The phononic crystal is a composite material formed by two or more elastic media according to different lattice period sequences. In the phononic crystal, materials with different densities and elastic constants are periodically compounded together according to a structure, the materials which are not communicated with each other are called scatterers, and the materials which are communicated into a whole are called matrixes. One of the most important characteristics of a phononic crystal is the band gap characteristic: when elastic waves propagate in the photonic crystal, a special dispersion relation can be formed under the action of an internal periodic structure, namely a band gap, the frequency range between dispersion relation curves is called as a band gap, and the elastic waves cannot propagate in the frequency range. By utilizing the property of band gap, a brand new vibration isolation and noise reduction material can be designed, so that the phononic crystal has wide application prospect in the engineering field.
The disruption of the ideal periodic structure of a phononic crystal is called a defect. Defects can be generally classified into point defects, line defects, and area defects according to their dimensions. The defects of the one-dimensional phononic crystal are mainly formed by periodic changes of local structures in a layered periodic structure, for example, scatterers at any positions are removed in the complete one-dimensional phononic crystal structure, so that a point defect structure is formed, and vibration is localized at the point. When a defect exists in a phononic crystal, a so-called defect state is generated in the band gap of the phononic crystal, and an elastic wave in the band gap can only be locally positioned at the defect or spread along the defect. The presence of defect states can have a significant effect on the bandgap properties of the phononic crystal. By utilizing the defect state characteristics of the material, the phononic crystal structure can be further optimally designed, so that a structure with better vibration isolation effect is designed.
Disclosure of Invention
The invention aims to provide a phononic crystal-based wheel vibration absorber for a high-speed railway train, which reduces vibration in medium and high frequency domains.
Specifically, the invention provides a phononic crystal-based high-speed railway train wheel vibration absorber, which is characterized in that: the point defect localized photonic crystal vibration absorption device comprises an upper cover plate, a lower cover plate, a point defect localized photonic crystal vibration absorption component and a Bragg type photonic crystal vibration absorption component, wherein the Bragg type photonic crystal vibration absorption component is arranged in a space formed by the upper cover plate, the lower cover plate and the point defect localized photonic crystal vibration absorption component.
Further, it is characterized in that: the upper cover plate and the lower cover plate are cuboids with the same size, and the length, the width and the height are 150-300 mm, 150-300 mm and 15-30 mm in sequence.
Further, it is characterized in that: the point defect localized phononic crystal vibration absorption component comprises a square sleeve and a plurality of scatterers, wherein the length, width and height of the square sleeve are 150-300 mm, 150-300 mm and 250-400 mm in sequence.
Further, it is characterized in that: the point defect localized phononic crystal scatterers and the Bragg scattering type phononic crystal scatterers are made of aluminum materials.
Further, it is characterized in that: the square sleeve and the Bragg type photonic crystal vibration absorption component base body are both made of epoxy resin
Further, it is characterized in that: point defects are introduced by removing scatterers at any positions in a complete photonic crystal periodic structure on the square sleeve to form a point defect localized photonic crystal vibration absorption assembly.
Further, it is characterized in that: the upper cover plate and the lower cover plate are all provided with threaded holes with the same quantity, and the square sleeve is provided with threaded holes matched with the threaded holes of the upper cover plate and the lower cover plate.
Further, it is characterized in that: the vibration isolation cushion layers are connected in series through the vibration transmission rods, the vibration transmission rods are fixed in threaded holes in the upper cover plate and the lower cover plate, the vibration isolation cushion layers are embedded into grooves of the buffer layers, the Bragg type photonic crystal vibration absorption assemblies are periodically and uniformly distributed on the vibration isolation cushion layers, and the buffer layers are fixed on the upper cover plate and the lower cover plate through triangular steel.
Further, it is characterized in that: the vibration transmission rod is hollow cylinder type, the hollow radius is 25 mm-35 mm, and the column thickness is 5 mm.
Further, it is characterized in that: the Bragg type photonic crystal vibration absorption assembly base body is of a cylindrical structure which is periodically and uniformly distributed on the vibration isolation cushion layer, a circular hole is processed on the cylinder, and the scattering body is arranged in the circular hole.
Further, it is characterized in that: the vibration transmission rod is made of steel materials, the vibration isolation cushion layer is made of rubber materials, and the buffer layer is made of foam concrete materials.
Further, it is characterized in that: the assembling process of the high-speed rail train wheel vibration absorber based on the phononic crystal comprises the following steps
(1) The vibration isolation cushion layer is processed by hollow round holes which are connected in series by a vibration transmission rod.
(2) The upper cover plate and the lower cover plate are respectively provided with a threaded hole, and the two ends of the vibration transmission rod are provided with threads matched with the upper cover plate and the lower cover plate, so that the vibration transmission rod is fixed on the upper cover plate and the lower cover plate.
(3) And grooves are processed on the buffer layer, and the vibration isolation cushion layer is embedded into the grooves.
(4) The rubber buffer plates are fixed on the upper cover plate and the lower cover plate by using triangular steel.
(5) And the upper cover plate and the lower cover plate are respectively fixed on the square sleeve by screws to complete the assembly.
The invention has the beneficial effects that:
1. by introducing a "point defect" phononic crystal structure, vibrations can be localized at the defect.
2. Through setting up the vibration isolation bed course, the buffer layer has improved the ability of shaking the absorption better.
3. By utilizing the band gap characteristic of the Bragg type phononic crystal and optimizing the arrangement, the vibration absorption capacity is improved while the periodicity of the periodic material is prolonged.
4. The invention has simple structure, easy installation and convenient installation on the axle of the high-speed railway train.
Drawings
Fig. 1 is a schematic perspective view of a high-speed railway train wheel vibration absorber based on a phononic crystal according to the invention.
Fig. 2 is an exploded schematic view of fig. 1.
Detailed Description
In order to make the technical solution and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.
The first embodiment is as follows: as described with reference to fig. 1 to 2, the phononic crystal-based high-speed railway train wheel vibration absorber of the present embodiment includes an upper cover plate 1, a lower cover plate 8, a vibration transmission rod 2, point defect localized phononic crystal vibration absorbing members 6 and 7, a bragg-type phononic crystal vibration absorbing member 3, a vibration isolation cushion 4, and a buffer layer 5.
The point defect localized photonic crystal vibration absorption assembly comprises a square sleeve 6 and a plurality of scattering bodies 7, wherein the scattering bodies 4 are uniformly distributed and fixedly arranged in circular holes in the square sleeve.
Wherein, the Bragg type photonic crystal vibration absorption component 3 comprises a circular cylinder and a plurality of scattering bodies, the plurality of scattering bodies are uniformly distributed and fixedly arranged in a circular hole on the cylinder,
the vibration isolation cushion layer 4 is connected in series through the vibration transmission rod 2, the vibration transmission rod 2 is fixed in threaded holes in the upper cover plate 1 and the lower cover plate 8, the vibration isolation cushion layer 4 is embedded into a groove of the buffer layer 5, the Bragg type photonic crystal vibration absorption assemblies 3 are periodically and uniformly distributed on the vibration isolation cushion layer 4, and the buffer layer 5 is fixed on the upper cover plate 1 and the lower cover plate 8 through triangular steel. Wherein the cushioning layer 5 is preferably integrally formed with a bottom wall and four side walls, the upper opening forming a recess. In another preferred embodiment, the upper part of the buffer layer is provided with a cover which can be opened and closed.
The circular hole on the base body cylinder of the bragg-shock absorbing assembly 3 in the present embodiment refers to a circular hole arranged on the unfolded plate surface of the sleeve. A plurality of bragg scattering-type phononic crystal scatterers may fill each respective through-hole arrangement.
The "point defect" localized phononic crystal vibration absorbing assembly of this embodiment introduces a "point defect" by removing a diffuser 7 at any position in the complete phononic crystal periodic structure on the square sleeve 6.
Preferably, the "point defect" localized phononic crystal scatterers 7 and bragg scattering type phononic crystal scatterers are annular thin sheet structures matched with the respective circular through holes. By the arrangement, the processing is convenient, the period number of the periodic material scatterer is greatly increased, and the vibration isolation effect in the band gap is remarkably improved.
Preferably, the Bragg type photonic crystal vibration absorption assembly base 3 is a cylinder which is periodically and uniformly distributed on the vibration isolation cushion layer, and the scattering body is in an annular sheet structure matched with a round hole in the cylinder.
Preferably, the "point defect" localized phononic crystal scatterers 7, bragg type scattering type phononic crystal scatterers are made of aluminum material.
Preferably, the square sleeve, the matrix of the bragg scattering type photonic crystal vibration absorbing assembly 3 is made of epoxy resin material.
Preferably, threaded holes are respectively processed on the upper cover plate 1 and the lower cover plate 8. So set up, be convenient for realize with the external part or the connection of structure that need keep apart the processing.
Preferably, both the upper and lower cover plates 1 and 8 are made of a rubber material.
Preferably, the upper cover plate 1 and the lower cover plate 8 are cuboids with the same size, and the length, the width and the height are 150-300 mm, 150-300 mm and 15-30 mm in sequence.
Preferably, the length, width and height of the square sleeve 6 are 150-300 mm, 150-300 mm and 250-400 mm in sequence.
Preferably, the vibration transfer rod 2 is a hollow cylinder type having a hollow radius of 25 to 35mm and a column thickness of 5 mm.
Preferably, the vibration transmission rod 2 is made of a steel material. So set up, be convenient for better vibration transmission.
Preferably, the vibration-isolating pad 4 is made of rubber. So set up, be convenient for further improve the ability of shaking.
Preferably, the buffer layer 5 is made of foamed concrete.
Preferably, the vibration transmission rod 2 is provided with threads matched with threaded holes of the upper cover plate 1 and the lower cover plate 8, and the arrangement is convenient for realizing the connection of the vibration transmission rod with the upper cover plate 1 and the lower cover plate 8.
Preferably, a circular groove is processed on the vibration isolation cushion layer 4, and the middle of the vibration isolation cushion layer 4 is hollowed. So set up, be convenient for arrange Bragg's type phononic crystal and inhale subassembly 3, be convenient for utilize vibration transfer rod 2 to establish ties vibration isolation cushion 4.
Preferably, the buffer layer 5 is provided with grooves and threaded holes. So set up, be convenient for utilize the triangle just fixed buffer layer structure 5, the overall structure's of being convenient for equipment.
The second embodiment is as follows:
the assembling process of the high-speed rail train wheel vibration absorber based on the phononic crystal comprises the following steps:
(1) the vibration isolation cushion layer is processed by hollow round holes which are connected in series by a vibration transmission rod.
(2) The upper cover plate and the lower cover plate are respectively provided with a threaded hole, and the two ends of the vibration transmission rod are provided with threads matched with the upper cover plate and the lower cover plate, so that the vibration transmission rod is fixed on the upper cover plate and the lower cover plate.
(3) And grooves are processed on the buffer layer, and the vibration isolation cushion layer is embedded into the grooves.
(4) The rubber buffer plates are fixed on the upper cover plate and the lower cover plate by using triangular steel.
(5) And the upper cover plate and the lower cover plate are respectively fixed on the square sleeve by screws to complete the assembly.
In practice, the following factors should be considered:
the number of cycles of the Bragg phononic crystal vibration absorbing assembly. The geometric dimension of the scatterer and the period number of the phononic crystals can be adjusted according to the geometric dimension of the vibration isolation cushion layer and the load borne by the wheel.
"Point defect" localizes the number of cycles of the photonic crystal vibration absorbing assembly. The geometric dimension of the scatterer and the period number of the phononic crystals can be adjusted according to the geometric dimension of the vibration absorption square sleeve and the load borne by the wheel.
3. The number of layers of the vibration isolation cushion layer. The number of layers of the vibration isolation cushion layer can be adjusted according to the geometric dimension of the vibration absorption square sleeve and the load borne by the wheel.
4. The size of the overall structure. The size of the whole structure can be adjusted according to the size of wheels, axle weight and axle of a high-speed railway train, wherein the length and width of the upper cover plate and the lower cover plate are consistent with the length and width of the square sleeve, and the size of the hollow part on the vibration isolation cushion layer is consistent with the size of the vibration transmission rod.
The working process is as follows:
when a train runs on a track, noise and vibration generated by wheel track irregularity excitation are input through a vibration transmission rod, the vibration excitation is attenuated in a vibration band gap of the photonic crystal within a certain frequency band range under the action of a band gap of the Bragg scattering type photonic crystal with pretightening force, and after secondary vibration absorption of a vibration isolation cushion layer and a buffer layer, part of elastic waves are localized at a defect position through a point defect localization photonic crystal vibration absorption assembly. The vibration isolation function is realized by introducing a point defect type phononic crystal structure and prolonging the period number of the periodic material.
The above-listed detailed description is only a specific description of a possible embodiment of the present invention, and they are not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention should be included in the scope of the present invention.
Claims (7)
1. The utility model provides a high-speed railway train wheel bump leveller based on phononic crystal which characterized in that: the device comprises an upper cover plate, a lower cover plate, a point defect localized photonic crystal vibration absorption component and a Bragg type photonic crystal vibration absorption component, wherein the Bragg type photonic crystal vibration absorption component is arranged in a space formed by the upper cover plate, the lower cover plate and the point defect localized photonic crystal vibration absorption component; the vibration absorber further comprises a vibration transfer rod, a vibration isolation cushion layer and a buffer layer, wherein the vibration isolation cushion layer is connected in series through the vibration transfer rod, the two ends of the vibration transfer rod are fixed in threaded holes of the upper cover plate and the lower cover plate, the vibration isolation cushion layer is embedded into a groove of the buffer layer, periodic uniform distribution of the Bragg type photonic crystal vibration absorption assembly is distributed on the vibration isolation cushion layer, the buffer layer is fixed on the upper cover plate and the lower cover plate through triangular steel, the buffer layer is integrally formed and is provided with a bottom wall and four side walls, and an upper opening is formed in the groove.
2. The phononic crystal-based wheel vibration absorber for high-speed railway trains according to claim 1, wherein: the upper cover plate and the lower cover plate are cuboids with the same size, and the length, the width and the height are 150-300 mm, 150-300 mm and 15-30 mm in sequence.
3. The phononic crystal-based high-speed railway train wheel vibration absorber of claim 2, wherein: the point defect localized phononic crystal vibration absorption component comprises a square sleeve and a plurality of scatterers, wherein the length, width and height of the square sleeve are 150-300 mm, 150-300 mm and 250-400 mm in sequence.
4. The phononic crystal-based high-speed railway train wheel vibration absorber of claim 3, wherein: the point defect localized phononic crystal scatterer and the Bragg type phononic crystal vibration absorption assembly scatterer are both made of aluminum materials.
5. The phononic crystal-based high-speed railway train wheel vibration absorber of claim 4, wherein: the square sleeve and the Bragg type photonic crystal vibration absorption assembly base body are made of epoxy resin.
6. The phononic crystal-based wheel vibration absorber for high-speed railway trains according to claim 5, wherein: point defects are introduced by removing scatterers at any positions in a complete photonic crystal periodic structure on the square sleeve to form a point defect localized photonic crystal vibration absorption assembly.
7. The phononic crystal-based wheel vibration absorber for high-speed railway trains according to claim 6, wherein: the upper cover plate and the lower cover plate are all provided with threaded holes with the same quantity, and the square sleeve is provided with threaded holes matched with the threaded holes of the upper cover plate and the lower cover plate.
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| CN110566618B (en) * | 2019-08-26 | 2020-12-15 | 上海宇航系统工程研究所 | Phononic crystal vibration isolation device |
| CN110541331A (en) * | 2019-08-28 | 2019-12-06 | 西南交通大学 | Track shock absorber and track traffic system |
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| CN101976559A (en) * | 2010-06-23 | 2011-02-16 | 北京科技大学 | Connecting method of variable cross-section phononic crystal elastic material |
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| CN107542827A (en) * | 2017-10-17 | 2018-01-05 | 吉林大学 | A kind of composite construction phonon crystal vibration isolating suspension |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101852115B (en) * | 2010-05-20 | 2012-12-19 | 西南交通大学 | Automotive exhaust muffler with composite three-dimensional phononic crystals |
| CN102878235B (en) * | 2012-09-21 | 2014-06-11 | 哈尔滨工程大学 | Compound phonon crystal rod with multi-dimensional vibration absorbing function |
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Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101976559A (en) * | 2010-06-23 | 2011-02-16 | 北京科技大学 | Connecting method of variable cross-section phononic crystal elastic material |
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| CN104179879A (en) * | 2014-07-29 | 2014-12-03 | 哈尔滨工业大学 | Circular sleeve type phononic crystal vibration isolator |
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