High-speed train snowplow

Abstract

The present invention relates to the field of high-speed train vehicle equipment technology and aerodynamic noise control technology, and provides a high-speed train snowplow, including a snowplow body, the snowplow body is a flat streamlined structure, the end of the snowplow body close to the bogie cabin is the rear end, and an active jet module for adding three-dimensional disturbance to the airflow is provided, and the other end of the snowplow body is the windward surface. Compared with the prior art, the present invention has an active jet module, which can effectively add three-dimensional disturbance to the airflow through multiple jet ports, thereby reducing the excitation of the airflow on the acoustic mode inside the bogie cabin, and effectively reducing the peak value of the top of the bogie cabin, the peak value of the rear wall and the amplitude of broadband aerodynamic noise.

Description

Technical Field

[0001] The invention belongs to the field of high-speed train vehicle equipment technology and aerodynamic noise control technology, and relates to a high-speed train snowplow. Background Art

[0002] The commercial operating speed of high-speed trains is constantly increasing. At present, the highest commercial operating speed in the world has reached 350km / h. The technical research and development system is constantly moving towards 400km / h and above. The noise level of high-speed trains is the core technical indicator that restricts its further speed increase. A large amount of actual operation experience shows that the noise problem is the most prominent in the environmental pollution of high-speed trains. When the running speed of high-speed trains exceeds 300km / h, aerodynamic noise will exceed wheel-rail rolling noise and traction noise and occupy a dominant position. The main aerodynamic noise sources of high-speed trains are the bogies, pantographs and car connections. Due to the large number of bogies, the far-field aerodynamic noise they generate is about 15dB higher than that of the pantograph. The results of acoustic wind tunnel experiments show that the bogie area of ​​the head car is the largest aerodynamic noise source among all bogie areas. The airborne sound transmission caused by aerodynamic noise of trains with a speed of 350km~380km / h accounts for the main position of the in-car noise, and the airborne noise in the bogie area is also the main contributor to the in-car noise. Therefore, effectively reducing and suppressing the noise in the bogie area of ​​the locomotive, improving the environmental quality along the railway and the noise level inside the vehicle are issues that need to be considered and resolved in the design and production of high-speed train vehicles. Figure 1 , Figure 2 This is a schematic diagram of the structure of a common snowplow.

[0003] China Publication No. CN110070850A discloses a streamlined through-flow type obstacle remover and its application, including an obstacle remover body, the obstacle remover body is a flat plate-like structure, the outer contour is a variable cross-section streamlined shape, the front end is a frontal surface, a through-flow opening is opened at the center of the frontal surface, a through-flow channel is arranged inside the obstacle remover body, a release opening is arranged on the rear end surface of the obstacle remover body, the through-flow opening guides the high-speed airflow to flow into the through-flow channel and flows out from the release opening, and the through-flow channel allows the high-speed airflow to flow out of the release opening obliquely downward from the front to the back and from the inside to the outside. This prior art has a certain effect of controlling aerodynamic noise, and the through-flow type obstacle remover reduces broadband noise by directing the front airflow to both sides, but because of its limited control effect on the shear layer, it has little effect on suppressing peak noise. Summary of the invention

[0004] The purpose of the present invention is to provide a high-speed train snowplow to overcome the problem that the aerodynamic noise in the bogie area of ​​the head car of the high-speed train cannot be effectively reduced.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] The present invention provides a high-speed train obstacles, including an obstacles body, wherein the obstacles body is a flat streamlined structure, the end of the obstacles body close to the bogie compartment is the rear end, an active jet module for adding three-dimensional disturbance to the airflow is provided, and the other end of the obstacles body is the windward surface.

[0007] Furthermore, the active jet module includes a plurality of jet ports, and the jet ports are distributed at the rear end of the obstacle remover at the same intervals along the span direction.

[0008] Furthermore, the number of the jet ports is 4 to 7.

[0009] Furthermore, the jet port is a square jet port.

[0010] Furthermore, the jet port is 35 to 45 mm away from the rear end edge of the obstacle remover body.

[0011] Furthermore, the length of the jet port along the flow direction is 35 to 45 mm.

[0012] Furthermore, the length of the jet port along the span direction is 95 to 105 mm.

[0013] Furthermore, the length of the jet port along the span direction is 24% to 26% of the overall width of the obstacle remover body.

[0014] Furthermore, the jet momentum coefficient of the active jet module is 0.071-0.081.

[0015] Furthermore, the jet momentum coefficient is controlled by using compressed air as an air source and a throttle valve and a flow meter to control the jet velocity of the jet orifice.

[0016] Compared with the prior art, the present invention has the following characteristics:

[0017] 1. The present invention has an active jet module, which can effectively increase three-dimensional disturbance to the airflow, thereby reducing the excitation of the airflow on the acoustic mode inside the bogie cabin, and effectively reducing the peak value of the top of the bogie cabin, the peak value of the rear wall and the amplitude of broadband aerodynamic noise.

[0018] 2. The active jet module of the present invention includes 4 to 7 jet ports, which can further effectively reduce the peak noise and broadband noise generated by the rear wall of the bogie cabin.

[0019] 3. In the present invention, the jet momentum coefficient is controlled by using compressed air as the air source and a throttle valve and a flow meter to control the jet velocity of the jet orifice, which has high flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a common obstacle avoider (front view);

[0021] Figure 2 It is a structural schematic diagram of a common snowplow (bottom view);

[0022] Figure 3 A schematic diagram of a high-speed train snowplow with an active jet structure according to the present invention;

[0023] Figure 4 It is a side view of the high-speed train snowplow with active jet structure of the present invention mounted on the head car of the high-speed train;

[0024] Figure 5 A comparison chart of one-third octave band test data of the bogie cabin top noise of the high-speed train snowplow with active jet structure of the present invention;

[0025] Figure 6 This is a comparison chart of one-third octave band test data of the bogie compartment rear wall noise of the high-speed train snowplow with active jet structure of the present invention.

[0026] Description of the markings in the figure:

[0027] 1—fender body, 2—jet port, 3—locomotive head, 4—bogie compartment. DETAILED DESCRIPTION

[0028] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0029] Example 1

[0030] The present invention provides a high-speed train obstacle avoider, such as Figure 3 The device is applied to high-speed trains and is used to reduce the aerodynamic noise generated in the bogie compartment 4 area. The cogwheel is installed at the front end of the bogie compartment, and includes a cogwheel body 1. The cogwheel body 1 is a flat streamlined structure. The end of the cogwheel body 1 close to the bogie compartment 4 is the rear end, and an active jet module is provided for adding three-dimensional disturbance to the airflow. The other end of the cogwheel body 1 is the windward surface.

[0031] Among them, the active jet module includes a plurality of jet ports 2, that is, a plurality of through-type jet ports 2 are arranged on the obstacle remover body 1. The function of the jet ports 2 is to deflect the shear layer toward the ground, increase the three-dimensional disturbance structure of the shear layer, change the excitation of the airflow on the cavity acoustic mode of the bogie cabin 4 and the aerodynamic noise of the shear layer, thereby reducing the generation of aerodynamic noise in the bogie cabin 4 area.

[0032] In this embodiment, the jet orifices 2 are rectangular and are distributed at the rear end of the obstacle remover body 1 at the same intervals along the span direction.

[0033] Specifically, the number of the jet ports 2 is 4 to 7, which are 35 to 45 mm away from the rear end edge of the obstacle remover body 1, have a length along the flow direction of 35 to 45 mm, and a length along the span direction of 95 to 105 mm. The length along the span direction is 24% to 26% of the overall width of the obstacle remover body 1.

[0034] This embodiment uses 5 jet outlets 2, which are 40 mm away from the rear end edge of the obstacle remover body 1, have a length of 40 mm along the flow direction, and a length of 100 mm along the span direction, and are evenly distributed at intervals of 300 mm along the span direction, that is, the jet outlet 2 accounts for 25% of the span width.

[0035] Specifically, the jet momentum coefficient of the active jet module is 0.071-0.081.

[0036] In this embodiment, the jet momentum coefficient is 0.076, the jet angle is perpendicular to the bottom surface of the snow remover, and the corresponding jet velocity is 0.35 times the incoming flow velocity, that is, when the train running speed is 40m / s, the jet velocity is about 14m / s.

[0037] The momentum coefficient is defined as follows:

[0038]

[0039] in, represents the total mass flow rate of the jet, U jet represents the average velocity of the jet 2, q ∞ is the incoming flow pressure, W is the width of the bogie compartment 4, and δ is the boundary layer thickness at the leading edge of the bogie compartment 4.

[0040] Specifically, the active jet module uses compressed air as an air source, controls the jet velocity of the jet port 2 through a flow meter, and further controls the jet momentum coefficient.

[0041] The high-speed train snowplow with an active jet module provided by the present invention has an outer contour that adopts a streamlined variable-section curve form transition to guide the flow from the bottom of the front of the vehicle 3 to the two sides of the snowplow body 1. An active jet structure is arranged at the bottom rear end to add three-dimensional disturbance to the shear layer that falls off from the trailing edge of the snowplow body 1. The excitation of the acoustic mode of the bogie cabin 4 by the shear layer between the trailing edge of the snowplow body 1 and the leading edge of the bogie cabin 4 can be changed, thereby reducing the peak noise in the bogie cabin 4 and the generation of broadband noise of the rear wall in the cabin during operation, and effectively improving the aerodynamic noise control effect in the bogie cabin 4 area.

[0042] like Figure 4 As shown, the snowplow is installed at the bottom of the locomotive 3 of the high-speed train, which is labeled as the locomotive 3 and the bogie compartment 4. The snowplow is installed at the front edge of the bogie compartment 4 of the high-speed train.

[0043] The noise reduction effect of the present invention has been verified by acoustic wind tunnel tests. The test model is a 1:20 high-speed train head 3 model with a bogie cabin 4 installed. The bottom rear end is connected to a smooth guide section to avoid strong vortex shedding at the rear of the car body to induce aerodynamic noise. The test results of the one-third octave band of the noise between the top and the rear wall of the bogie cabin 4 of the high-speed train using the active jet device of the present invention with an active jet structure and a train model without the device at a wind speed of 40m / s are as follows: Figure 5 , 6 As shown, Figure 5 For the top measurement point, the peak energy is reduced; Figure 6 For the rear wall measurement point, both the peak and broadband energy are reduced. It can be found that the top of the bogie cabin 4 with the obstacle clearer equipped with an active jet structure has a noise with a center frequency of 630Hz of the one-third octave band spectrum reduced from 113.0dB(A) to 109.7dB(A) when other frequency bands are not much different from those without the noise reduction device. Moreover, for the position of the rear wall of the bogie cabin 4, after installing the active jet device, each frequency band of 200Hz-4kHz is reduced by at least 2dB(A), and the total sound pressure level is reduced by 2.1dB(A), achieving a good noise reduction effect. It can be seen that since the present invention has an active jet module, it can effectively increase the three-dimensional disturbance to the airflow, thereby reducing the excitation of the airflow on the acoustic mode inside the bogie cabin, and effectively reducing the peak value of the top of the bogie cabin, the peak value of the rear wall and the broadband aerodynamic noise amplitude.

[0044] Compared with the proportional model used in the test, the high-speed train actually running on the line has a higher Reynolds number around the flow. The present invention will be more effective in improving the flow separation at the trailing edge of the snowplow body 1, alleviating the flow impact on the bogie cabin 4 area, and the fluid interaction between the various geometric bodies in the bogie cabin 4. The resulting noise reduction effect will also be more significant, which can effectively reduce the peak noise and broadband noise felt by the passengers on the top of the bogie cabin 4 in the train.

[0045] Example 2

[0046] The present invention is installed at the front end of the bogie cabin 4 in the bogie cabin 4 area outside the front part 3 to reduce the generation and radiation of aerodynamic noise in this area, and the rest is the same as that of embodiment 1.

[0047] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A high-speed train snowplow, characterized in that: The device comprises a deflector body (1), wherein the deflector body (1) is a flat streamlined structure, wherein one end of the deflector body (1) close to the bogie compartment (4) is a rear end, and an active jet module for adding three-dimensional disturbance to the airflow is provided, and the other end of the deflector body (1) is a windward surface; The active jet module comprises a plurality of jet ports (2), wherein the jet ports (2) are distributed at equal intervals along the span direction on the rear end bottom plane of the obstacle remover body (1).

2. A high-speed train snowplow according to claim 1, characterized in that: The number of the jet ports (2) is 4 to 7.

3. A high-speed train snowplow according to claim 1, characterized in that: The jet port (2) is a square jet port (2).

4. A high-speed train snowplow according to claim 1, characterized in that: The jet port (2) is 35 to 45 mm away from the rear end edge of the obstacle remover body (1).

5. A high-speed train snowplow according to claim 1, characterized in that: The length of the jet port (2) along the flow direction is 35-45 mm.

6. A high-speed train snowplow according to claim 1, characterized in that: The length of the jet port (2) along the span direction is 95-105 mm.

7. A high-speed train snowplow according to claim 1, characterized in that: The length of the jet port (2) along the span direction is 24% to 26% of the overall width of the obstacle remover body (1).

8. A high-speed train snowplow according to claim 1, characterized in that: The jet momentum coefficient of the active jet module is 0.071-0.

081.

9. A high-speed train snowplow according to claim 8, characterized in that: The jet momentum coefficient is controlled by using compressed air as an air source and a throttle valve and a flow meter to control the jet velocity of the jet orifice (2).

Images