CN113859296B - Barrier with passive turbulence structure and application thereof - Google Patents
Barrier with passive turbulence structure and application thereof Download PDFInfo
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- CN113859296B CN113859296B CN202111246877.5A CN202111246877A CN113859296B CN 113859296 B CN113859296 B CN 113859296B CN 202111246877 A CN202111246877 A CN 202111246877A CN 113859296 B CN113859296 B CN 113859296B
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- 230000004888 barrier function Effects 0.000 title claims abstract description 36
- 230000003137 locomotive effect Effects 0.000 claims description 6
- 239000000956 alloy Substances 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims description 2
- 230000003993 interaction Effects 0.000 abstract description 3
- 230000000694 effects Effects 0.000 description 9
- 238000012360 testing method Methods 0.000 description 6
- 230000009467 reduction Effects 0.000 description 5
- 230000005284 excitation Effects 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 238000010008 shearing Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61F—RAIL VEHICLE SUSPENSIONS, e.g. UNDERFRAMES, BOGIES OR ARRANGEMENTS OF WHEEL AXLES; RAIL VEHICLES FOR USE ON TRACKS OF DIFFERENT WIDTH; PREVENTING DERAILING OF RAIL VEHICLES; WHEEL GUARDS, OBSTRUCTION REMOVERS OR THE LIKE FOR RAIL VEHICLES
- B61F19/00—Wheel guards; Bumpers; Obstruction removers or the like
- B61F19/06—Nets, catchers, or the like for catching obstacles or removing them from the track
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Current-Collector Devices For Electrically Propelled Vehicles (AREA)
Abstract
The invention relates to a barrier with a passive turbulence structure and application thereof, comprising a barrier body, wherein the barrier body is of a flat streamline structure, the rear end of the bottom of the barrier body is provided with the passive turbulence structure, the profile of the turbulence structure is cylindrical and is vertical to the direction of air flow, and the ratio of the distance between the turbulence generator and the flat end surface of the rear end of the barrier body to the diameter of the turbulence generator is less than 1. Compared with the prior art, the invention changes the angle of the airflow entering the bogie cabin by utilizing the interaction of the cylindrical wake flow and the shear layer, and effectively reduces the pneumatic noise generated in the bogie area of the high-speed train.
Description
Technical Field
The invention relates to the technical field of high-speed train equipment and pneumatic noise control, in particular to a barrier with a passive turbulence structure and application thereof.
Background
The high-speed railway has been developed rapidly in various countries of the world by virtue of its advantages of safety, reliability, comfort, convenience, transportation service, high efficiency, energy saving and the like. In order to better promote the development of transportation industry, greatly improve transportation efficiency, solve the railway transportation pressure in the peak period of passenger flow, the railway high-speed has become an important trend of the development in the world today.
As train operation speeds continue to increase, environmental problems are increasingly raised. A large amount of practical operation experience shows that the noise problem is most prominent in the environmental pollution of the high-speed train. When the running speed of the high-speed train exceeds 300km/h, aerodynamic noise will dominate over wheel track rolling noise and traction noise. The main pneumatic noise source of the high-speed train is the joint of the bogie, the pantograph and the carriage. Due to the large number of bogies, the far-field aerodynamic noise generated by the bogies is about 15dB higher than that generated by the pantograph. The acoustic wind tunnel experimental results show that the head truck bogie area is the largest aerodynamic noise source in all bogie areas. The air sound transmission of the train at the speed of 350 km-380 km caused by pneumatic noise is dominant in the noise in the train, and the air sound in the bogie area is also the most dominant contribution source of the noise in the train. Therefore, the noise in the locomotive bogie area is effectively reduced and suppressed, the environmental quality along the railway and the noise level in the locomotive are improved, and the noise level is a problem to be considered and solved in the design and production of the high-speed train.
The patent 110070850A discloses a streamline flow-through type barrier and application thereof, the streamline flow-through type barrier comprises a barrier body, the barrier body is of a flat plate-shaped structure, the outline is of a streamline shape with a variable cross section, the front end is a flow-facing surface, a flow-through opening is formed in the center of the flow-facing surface, a flow-through channel is arranged in the barrier body, a flow-out opening is formed in the rear end face of the barrier body, the flow-through opening guides high-speed airflow to flow into the flow-through channel and flow out of the flow-out opening, and the flow-through channel enables the high-speed airflow to flow out of the flow-out opening obliquely downwards from front to back and from inside to outside. Patent CN111071272a discloses a barrier with pits at the rear end of the bottom, which comprises a barrier body, wherein the barrier body is of a flat structure, the outline is of a streamline shape with a variable cross section, the front end is a flow-facing surface, and a plurality of rows of pits are arranged at the rear end of the bottom of the barrier body. The above-described structure of the barrier has a certain effect of controlling aerodynamic noise, and the flow-through barrier reduces broadband noise by guiding the front air flow to both sides, but has a small effect of suppressing peak noise due to a limited effect of controlling the shear layer. The pit baffle reduces peak noise by adding turbulence to the shear layer, but has a large increase in broadband noise from 1kHz to 5 kHz. And the two are mainly analyzed aiming at the noise reduction effect of far-field noise, so that near-field noise analysis in the cabin is less.
Disclosure of Invention
The invention aims to solve the problems and provide the obstacle deflector with the passive turbulence structure and the application thereof, wherein the obstacle deflector can effectively reduce pneumatic noise in a bogie area of a locomotive of a high-speed train.
The aim of the invention is achieved by the following technical scheme:
the utility model provides a pilot with passive vortex structure, includes pilot body, pilot body is flat streamline structure, and the outline is the streamline of variable cross section, and the front end is the windward side, and the rear end is the plane end face, the rear end bottom of pilot body sets up passive vortex structure, passive vortex structure for the protrusion the sand grip form structure that pilot body set up, and with the rear end plane end face of pilot body is parallel, and length direction is perpendicular with the air current direction.
The invention is provided with the turbulent flow structure at the rear end of the bottom of the barrier, and the turbulent flow structure has the functions of changing the angle of air flow entering the bogie cabin, reducing the excitation of the cavity acoustic mode of the bogie, and reducing the impact of a shearing layer on the rear wall of the bogie cabin, thereby reducing the generation of pneumatic noise.
Further, the passive turbulence structure is cylindrical.
Further, the diameter (D) of the cylinder is 45-55mm, and the smaller the diameter, the smaller the peak noise reduction amplitude, but the larger diameter introduces higher cylinder peak noise energy, and thus is preferably 50mm.
Further, the passive turbulence structure is arranged near the rear end of the baffle body, the distance between the passive turbulence structure and the flat end surface of the rear end of the baffle body is G, in order to enable the cylindrical wake to bring the shearing layer of the baffle to the lower part, G/D <1 > is required, D is the diameter of the cylinder, and the G range is 30-40 mm, preferably 35mm.
Further, the width of the passive turbulence structure is equal to the width of the tail of the barrier body, and is about 3200mm.
Further, the passive turbulence structure is mounted on the deflector body through a multi-point support.
Further, the passive turbulence structure is made of alloy materials and is a solid structure.
The application of the obstacle deflector of the passive turbulence structure is that the obstacle deflector is applied to a high-speed train and is used for reducing pneumatic noise generated in a bogie area.
The barrier is closely attached to the nose cone bottom area of the head of the high-speed train.
The baffle with the passive turbulence structure provided by the invention has the advantages that the outline profile is transited in a streamline variable section curve mode, the incoming flow at the bottom of the vehicle head is guided to the two sides of the baffle, the cylindrical passive turbulence structure is arranged at the rear end of the bottom, the angle of the airflow entering the baffle can be changed through the interaction of the cylindrical wake and the shear layer, the excitation of the shear layer at the rear edge of the baffle and the front edge of the bogie cabin on the acoustic mode of the bogie cabin is inhibited, the impact of the shear layer on the rear wall of the bogie cabin is reduced, the peak noise in the bogie cabin and the broadband noise of the rear wall of the bogie cabin in the operation process are reduced, and the pneumatic noise control effect of the bogie area is effectively improved.
The invention can also be installed at the front edge of the bogie cabin in the region of the bogie outside the locomotive to reduce the generation and radiation of aerodynamic noise in this region.
Compared with the prior art, the invention has the following advantages:
(1) The baffle with the passive turbulence structure can effectively change the angle of entering air flow into the bogie cabin, thereby reducing the excitation of the air flow to the acoustic mode in the bogie cabin and effectively reducing the peak noise of the top and the rear wall of the bogie cabin.
(2) The baffle with the passive turbulence structure can reduce the impact of air flow on the rear wall of the bogie cabin and can effectively reduce broadband noise generated by the rear wall of the bogie cabin.
Drawings
FIG. 1 is a schematic view (front view) of a conventional barrier;
FIG. 2 is a schematic view (bottom view) of a conventional barrier;
FIG. 3 is a schematic view of a barrier with passive spoiler structure according to the present invention;
FIG. 4 is a side view of the deflector with passive spoiler structure of the present invention mounted on a high speed train;
FIG. 5 is a graph comparing test data of one third octave of noise at the top of a truck cabin of a barrier with a passive spoiler structure of the present invention;
FIG. 6 is a graph comparing test data of one third octave of noise of the rear wall of a truck cabin of a barrier with a passive spoiler structure of the present invention;
in the figure: 1-a barrier body; 2-a passive turbulence structure; 3-headstock; 4-a bogie; 5-rail.
Detailed Description
The invention will now be described in detail with reference to the drawings and specific examples.
Fig. 1-2 are schematic structural diagrams of a common pilot without the function of reducing aerodynamic noise in the region of a truck at the head of a high-speed train.
In order to effectively control pneumatic noise generated by running of a high-speed train, the invention provides a baffle with a passive turbulence structure, which is used for reducing the pneumatic noise in a bogie area of a locomotive of the high-speed train, and as shown in figures 3-4, the baffle comprises a baffle body 1, wherein the baffle body 1 is of a flat structure, the outline is of a streamline shape with a variable cross section, the front end is a flow-facing surface, the rear end of the bottom of the baffle body 1 is provided with a cylindrical turbulence structure 2, the turbulence structure is hoisted at the rear half end of the bottom of the baffle, the distance between the turbulence structure and the bottom of the baffle is 35mm, the diameter of a cylinder is 50mm, and the width of the turbulence structure is equal to the tail of the baffle to 3200mm.
As shown in fig. 4, the barrier is mounted at the bottom of the head of the high-speed train, and is labeled as the head 3, the bogie 4 and the steel rail 5, and the barrier is closely attached to the nose cone bottom area of the head of the high-speed train.
The noise reduction effect of the invention is verified by an acoustic wind tunnel test, and the test model is a high-speed train head model with a bogie installed at a ratio of 1:20. As shown in the results of comparing the test results of one third octave of noise at the inner top of the bogie cabin and the rear wall of the bogie cabin at the wind speed of 40m/s by adopting the train model with the passive turbulence structure and the common obstacle deflector, as shown in figures 5 and 6, the peak noise at the top of the bogie cabin of the obstacle deflector with the passive turbulence structure is reduced from 121.2dB (A) to 105.6dB (A), and the position of the rear wall of the bogie cabin is reduced by 5-7 dB (A) at each frequency band of 500Hz-10kHz, and the total sound pressure level is reduced by 6.2dB (A), thereby obtaining good noise reduction effect.
Compared with a proportional model used in a test, the invention has the advantages that the effect of improving the flow separation of the rear edge of the barrier and relieving the flow impact of the bogie area and the fluid interaction between geometric bodies in the bogie cabin is better, the noise reduction effect generated by the flow separation is more obvious, and the peak noise and the broadband noise felt by passengers at the top of the bogie cabin in the train can be effectively reduced.
The previous description of the embodiments is provided to facilitate a person of ordinary skill in the art in order to make and use the present invention. It will be apparent to those having ordinary skill in the art that various modifications to these embodiments can be made and that the general principles set forth herein may be applied to other embodiments without the inventive faculty. Therefore, the present invention is not limited to the above-described embodiments, and those skilled in the art, based on the present disclosure, should make improvements and modifications without departing from the scope of the present invention.
Claims (6)
1. The utility model provides a pilot with passive vortex structure, includes pilot body (1), pilot body (1) is flat streamline structure, and the outline is the streamline of variable cross section, and the front end is the windward side, and the rear end is the plane end face, characterized by, pilot body (1) rear end bottom sets up passive vortex structure (2), passive vortex structure (2) are protrusion strip form structure that protrusion pilot body (1) set up, and parallel with pilot body (1) rear end plane end face, length direction is perpendicular with the air current direction;
the passive turbulence structure (2) is cylindrical;
the passive turbulence structure (2) is arranged close to the rear end of the obstacle deflector body (1), and the distance between the passive turbulence structure and the flat end surface of the rear end of the obstacle deflector body (1) is as followsGIn order for the cylindrical wake to be able to bring the sheared layer of the deflector under it, it is sufficient thatG/D <1, D is the diameter of a cylinder;
the width of the passive turbulence structure (2) is equal to the tail of the barrier body;
the passive turbulence structure (2) is arranged on the obstacle deflector body (1) through a multi-point support.
2. The baffle with passive spoiler structure according to claim 1, characterized in that the passive spoiler structure (2) is located at a distance from the rear end planar end surface 30-40 mm of the baffle body (1).
3. The baffle with passive spoiler structure according to claim 1, characterized in that the passive spoiler structure (2) has a width of 3100-3300, mm.
4. The baffle with the passive turbulence structure as claimed in claim 1, wherein the passive turbulence structure (2) is made of alloy material and is a solid structure.
5. Use of a barrier with passive spoiler structure according to any of claims 1-4, in a high speed train for reducing aerodynamic noise generated in the bogie area.
6. Use of a barrier with passive turbulence structure as claimed in claim 5, wherein the barrier is in close contact with the nose cone bottom area of the locomotive of the high speed train.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111246877.5A CN113859296B (en) | 2021-10-26 | 2021-10-26 | Barrier with passive turbulence structure and application thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111246877.5A CN113859296B (en) | 2021-10-26 | 2021-10-26 | Barrier with passive turbulence structure and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113859296A CN113859296A (en) | 2021-12-31 |
| CN113859296B true CN113859296B (en) | 2024-03-26 |
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| CN113859296A (en) | 2021-12-31 |
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