KR20130120214A - Aerodynamic noise reduction device for high speed train - Google Patents

Abstract

The present invention relates to an aerodynamic noise reduction device for a high speed train, which comprises: a plate-shaped body installed in the interval between train bodies of the high speed train; multiple swirl control vanes which are protruding from the rear of the body to be separated from each other; and a coupling member which has a first coupling groove on one side thereof and a second coupling groove on the other side. A coupling part formed on one end of body is inserted into the first coupling groove. The end of the high speed train is coupled to the second coupling groove. Accordingly, the present invention exhausts the flow of air flowing into the interval between the train bodies of the high speed train, which is the main cause of aerodynamic noise, to the outside using the swirl control vanes; reduces a rapid flow change by continuing a separation phenomenon that the flow of the air is separated from the surface of the train bodies; reduces aerodynamic noise caused by the rapid flow change and a pressure change by reducing the pressure change; improves the appearance of the train by detachably coupling the body having the swirl control vanes to the train using the coupling member; and minimizes maintenance costs when the aerodynamic noise reduction device is repaired.

Description

Aerodynamic Noise Reduction Device for High Speed Train

The present invention relates to an apparatus for reducing aerodynamic noise of a high-speed railway vehicle in which a vortex suppression target is a bio-mimetic owl, and more specifically, a vortex suppression target is formed in a body installed at the end of the vehicle, and the vortex suppression target is formed of a fluid. The present invention relates to an aerodynamic noise reduction device for a high-speed railway vehicle that controls the flow, generates a small vortex, and prevents the generation of a large vortex due to the generation of a small vortex, thereby reducing the aerodynamic noise generated in the space between the high-speed railway vehicles.

In general, high-speed rail cars are being researched for the purpose of high speed, but it is well known that the noise and vibration increase due to the speed increase adversely affect the passenger comfort and the residential area near the railway.

In particular, when the speed of the high-speed railway vehicle is more than 200km / h, the surrounding fluid of the high-speed railway vehicle separation of the turbulence and vortex divergence occurs, resulting in a significant increase in aerodynamic noise.

Currently, high-speed railway vehicles are being researched for speeds of 200 km / h or more, and thus increasing aerodynamic noise is inevitable.

The aerodynamic noise of the high-speed railway vehicle is caused by the space between the railroad cars (cars) and the railroad cars (cars) and the bogie, which is unstable due to the space between the car and the bogie. As a result, flow separation occurs and thus aerodynamic noise is generated.

In order to reduce the noise and give passengers a comfortable ride and minimize the damage of noise to the outside, various proposals have been made. Among them, the following provisions have been made to reduce the noise generated in the space between the vehicle and the vehicle.

In Korea Registered Utility Model No. 20-0202088 (2000.08.28), noise is leaked through the connection part of the connection device that is used as an effective space for passengers who move the vehicle between vehicles by a passage between them. Fastened to the opposite position of the sealing rubber piece having a fixing part integrally formed at the outer end of the connecting device, the sealing rubber piece to be fitted to be fixed to the one end of the fixing part, and the sealing rubber piece to the fixed part so as to prevent the entry, In the meantime, the vehicle body fixing part of the vehicle is fitted to provide a light rail noise preventing device consisting of a brush which is in contact with the longitudinal direction.

In the Republic of Korea Utility Model Registration No. 20-0211873 (Nov. 16, 2000), the outer circumferential surface of the quadrilateral support frame is joined to join a plurality of fabrics to prevent external noise from entering the room as much as possible and to improve the oral resistance and maintainability. The connecting membrane is secured by sewn to be looped in one direction, and the connecting membrane is composed of a double aramid structure in sol tarpaulin, and the outer shell is covered with a sound absorbing material and a leather in turn, and finished with sol tarpaulin. On the other hand, it provides an inter-vehicle connecting film of the railroad car made by attaching a slide fastener in the transverse direction of the support frame on the lower surface.

In Korean Patent No. 10-0358023 (October 10, 2002), a device capable of changing the aerodynamic shape of a railroad vehicle, that is, reducing the joint air drag of the flow section against movement (driving) generated on the outer surface by the cavity A railroad car having an air wall along the outer wall and an outer wall in which the cavity is present, and a device for reducing the air drag generated by the cavity, the cavity facing the front edge and the air flow direction. And a rear edge separated from the front edge, the apparatus provides a railway vehicle with a device for reducing the joint air drag of the flow section, including a blade disposed parallel to the outer wall of the vehicle and overlapping the front edge of the cavity.

As described above, in order to reduce noise generated by high-speed traveling of a high-speed railway vehicle, the front head of the high-speed railway vehicle is designed by aerodynamically minimizing the air resistance, or by attaching a cover to the bogie and attaching a cover to the space between the cars to reduce the noise. In order to reduce the noise, the skirt installation interferes with the propagation of the noise source rather than reducing the noise source itself, thereby reducing the environmental noise caused by the skirt. However, the indoor noise of the high speed railway vehicle increases.

The cover also reduces the noise source itself, but incurs high costs in maintenance.

According to the present invention, if the body formed with the vortex suppression target focused on the optimized owl feather shape is installed in the intervessel space of the high-speed railway vehicle, the vortices are dispersed to the outside by dispersing the flow flowing into the intervessel space, which is the main cause of aerodynamic noise. The purpose of the present invention is to provide an aerodynamic noise reduction device for a high-speed railway vehicle that can sustain a separation phenomenon in which the flow falls off the surface, reduce a sudden flow change, and reduce pressure fluctuations, thereby reducing aerodynamic noise. have.

The present invention includes a plate-shaped body installed in the inter-vehicle space of the high-speed railway vehicle and a plurality of vortex restraint targets protruding to the rear of the body in order to reduce aero sound generated in the inter-vehicle space when the high-speed railway vehicle is running.

At this time, the body according to the present invention is formed of a plate, the eddy current suppressor has a length of 21 ~ 27mm, a diameter of 5 ~ 7mm cylindrical, can be formed spaced apart from each other at intervals of 5 ~ 7mm.

And the eddy current suppressor according to the present invention may be formed to be deflected at 10 ~ 20 ° in one direction.

In addition, the vortex control target according to the present invention may be formed to be curved protruding the end, or the vortex control target may be formed narrower toward the end.

In addition, a coupling portion having a 'T' shape is formed at one end of the body according to the present invention, and a first coupling groove to which the coupling portion is inserted and coupled is formed at one side, and an end of the high speed railway vehicle is fitted to the other side. A coupling member having two coupling grooves may be further included.

Aerodynamic noise reduction device of a high-speed railway vehicle according to the present invention has the following effects.

First, if the body with the vortex suppression target, which is focused on the optimized owl feather shape, is installed in the inter-vehicle space of the high-speed railway vehicle, the vortex-suppressor will disperse the flow flowing into the inter-vehicle space, which is the main cause of aerodynamic noise, and discharge it to the outside. Noise can be reduced.

Second, since the flow flowing into the inter-vehicle space flows out through the vortex restraint, the delamination of the flow falling off the surface is continued, thereby reducing the abrupt flow change and reducing the pressure fluctuation. Aerodynamic noise due to this can be reduced.

Third, by constructing the detachable body formed with the vortex suppression target on the high-speed railway vehicle as a coupling member, it does not impair the aesthetic appearance of the vehicle, and does not require much cost when maintaining the aerodynamic noise reduction device.

1 is a perspective view showing the configuration of aero noise reduction device of a high-speed railway vehicle according to the present invention.
Figure 2 is an exemplary view showing that the end of the vortex inhibiting target according to the configuration of the present invention is formed to be curved.
Figure 3 is an exemplary view showing that narrower toward the end of the eddy current suppression target according to the configuration of the present invention.
4 is an exemplary view showing a state in which the aerodynamic noise reduction device of the high-speed railway vehicle of the present invention is installed in the inter-vehicle space of the high-speed railway.
5 is an exemplary view showing a flow (wind tunnel) flow of the vortex control target according to the configuration of the present invention.
6 is an exemplary view showing a criterion of a control factor according to the configuration of the present invention.
7 is a graph showing the main effect diagram for each control factor according to the configuration of the present invention.
8 is a graph showing the interaction action of the control factor according to the configuration of the present invention.
9 is a graph showing the noise reduction effect according to the scale ratio of the eddy current control target according to the configuration of the present invention.
10 is an exemplary view showing a state of flow occurring in the conventional high-speed rail vehicle terminal.
11 is an exemplary view showing a state of flow generated in the aerodynamic noise reduction device of the high-speed railway vehicle of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The terms and words used in the specification and claims should not be construed to be limited to ordinary or dictionary meanings, and the inventor should appropriately define the concept of the term to describe its invention in the best way possible It should be construed in the meaning and concept consistent with the technical idea of the present invention.

Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and are not intended to represent all of the technical ideas of the present invention. Therefore, It should be understood that there may be variations.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment according to the present invention will be described in detail, Figure 1 is a perspective view showing the configuration of aerodynamic noise reduction device of a high-speed railway vehicle according to the present invention, Figure 2 according to the configuration of the present invention Figure 3 is an exemplary view showing that the end of the vortex inhibiting target is formed to be curved protruding, Figure 3 is an exemplary view showing that narrower toward the end of the vortex suppression target according to the configuration of the present invention, Figure 4 is aerodynamic of the high-speed railway vehicle of the present invention Figure 5 is an exemplary view showing a state in which the noise reduction device is installed in the inter-vehicle space of the high-speed railway, Figure 5 is an exemplary view showing the flow (wind tunnel) flow of the eddy current control target according to the configuration of the present invention, Figure 6 is a configuration of the present invention Figure 7 is an exemplary view showing the criteria of the control factor according to, Figure 7 is a graph showing the main effect diagram for each control factor according to the configuration of the present invention, Figure 8 is a control factor according to the configuration of the present invention 9 is a graph showing the interaction action, Figure 9 is a graph showing the noise reduction effect according to the scale ratio of the eddy current suppression target according to the configuration of the present invention, Figure 10 is an example showing the appearance of the flow occurring in the conventional high-speed railway vehicle end Figure 11 is an exemplary view showing a state of the flow generated in the aerodynamic noise reduction device of the high-speed railway vehicle of the present invention.

First of all, the present invention assumes that the owl feathers reduce flight noise, construct an imitation model of this function, and construct an aerodynamic noise reduction device accordingly.

Noise suppression by owl feathers is in Vortex Generator, and aerodynamic noise is caused by vortex of air current. In the case of owls, small vortex is generated around feathers by owl feathers. It suppresses the generation of vortex and suppresses aerodynamic noise.

1 to 4, an aerodynamic noise reduction device of a high speed railway includes a plate-shaped body 10 installed in a vehicle space of a high speed railway vehicle, and the body 10 is a plate type. to be.

And it is preferable that the plurality of vortex suppression target 20 protruding to the rear of the body 10 is 21 ~ 27mm in length, 5 ~ 7mm in diameter cylindrical, spaced apart from each other at intervals of 5 ~ 7mm.

In addition, the eddy current suppressor 20 is preferably formed to be deflected by 10 to 20 ° in one direction.

And the vortex suppression target 20 is formed to be curved protruding the end, or the vortex suppression target 20 is preferably formed narrower toward the end.

In addition, a coupling portion 11 having a 'T' shape is formed at one end of the body 10, and a first coupling groove 31 is formed at one side to which the coupling portion 11 is inserted and coupled. A coupling member 30 having a second coupling groove 32 to which the end of the high speed railway vehicle is fitted and coupled may be included.

Looking at the body 10 and the eddy current suppressor 20, which is the gist of the present invention described above in more detail.

First, the body 10 is not limited in size and thickness as a plate shape as a whole.

And one end of the body 10 is formed with a coupling portion 11 of the 'T' shape along the length, the other end is formed with a vortex inhibitory target 20.

The eddy current suppressor 20 is formed in the shape of a circular cylinder, the length is 21 ~ 27mm, the diameter of 5 ~ 7mm protruding from the body 10, when the body 10 is viewed with respect to the plane It is preferably formed to be deflected at 10 to 20 degrees or -10 to -20 degrees in the X-axis direction.

And the end of the vortex control target 20 is formed to be curved protruding as shown in Figure 2, or as shown in Figure 3 the end of the vortex control target 20 may be formed narrower toward the rear end.

In addition, the eddy current suppressor 20 is preferably formed spaced apart from each other at intervals of 5 ~ 7mm along the body (10).

The reason for limiting the length, diameter, X-axis direction, and spacing of the vortex inhibitory target 20 is as shown in the following experiment. This is because if the vortex suppression target 20 is formed outside the limited range, the effectiveness of reducing aerodynamic noise is lowered.

In addition, the coupling member 30 is to fix the body 10 to the end of the high-speed railway vehicle, the coupling portion 11 of the body 10 is inserted into the first coupling groove 31 is coupled to one side On the opposite side, a second coupling groove 32 is formed in which a mud-flip (not shown), which is an end of the high speed railway vehicle, is fitted and engaged.

At this time, when the mud flip (not shown), which is an end of the high speed railway vehicle, is fitted into the second coupling groove 32, the second coupling groove 32 is fastened by a bolt as a fixing means from the outside to prevent the high speed railway vehicle from vibrating by the fluid when the high speed railway vehicle is traveling. It can be attached and detached so that there is no inconvenience in replacing the body when maintenance of space and end of service life.

The objective effect obtained by the practice of the present invention can be seen by the following experiment, as shown in Figure 6 and Table 1, the control factors (length of the vortex inhibitory target, X-axis angle, Z-axis angle, thickness (diameter), Intervals) to 5 factors and each level to 3 levels.

Control factor
level unit
One 2 3 Length (A) 10 12 14 mm X axis angle (B) 0 15 30 Deg Z axis angle (C) 0 15 30 Deg Thickness (diameter) (D) One 2 3 mm interval (E) One 2 3 mm

Table 2 shows the orthogonal array table assigned by the orthogonal array method. As shown in Table 2, the noise factor is uniformly applied, so that the orthogonal array is not affected when the simulation is performed.

No. A B C D E Noise factor One One One One One One One 2 One One One One 2 One 3 One One One One 3 One 4 One 2 2 2 One One 5 One 2 2 2 2 One 6 One 2 2 2 3 One 7 One 3 3 3 One One 8 One 3 3 3 2 One 9 One 3 3 3 3 One 10 2 One 2 3 One One 11 2 One 2 3 2 One 12 2 One 2 3 3 One 13 2 2 3 One One One 14 2 2 3 One 2 One 15 2 2 3 One 3 One 16 2 3 One 2 One One 17 2 3 One 2 2 One 18 2 3 One 2 3 One 19 3 One 3 2 One One 20 3 One 3 2 2 One 21 3 One 3 2 3 One 22 3 2 One 3 One One 23 3 2 One 3 2 One 24 3 2 One 3 3 One 25 3 3 2 One One One 26 3 3 2 One 2 One 27 3 3 2 One 3 One

In order to compare the amount of vortex through numerical analysis, the vortex control blade 20 is modeled. In order to model 27 cases of the vortex control blade 20 of the orthogonal array table of Table 2 using a CAD modeling program and to increase the computational efficiency, Model the model by limiting the number of the eddy current suppressor 20 to three.

Hypermesh was used to construct the numerical grid, and the division grid network was formed by the control grid of the high-speed rail vehicle surface and the analysis area with a small control volume, and the computational grid was about 600,000 to 800,000 tetrahedrals. It consists of a grid.

Boundary conditions and governing equations are fixed in all cases in terms of density, temperature, and viscosity of air flowing from the inlet, and the flow is freely exited at the outlet.

Fluid (air) Density 1.225 kg / m³ Temperature 288.16 K Viscosity 1.7894e-05 kg / m-s

At this time, the velocity of the air flowing from the inlet was set to 55.56 m / s uniformly as the boundary condition.The wall surface of the modeling was set to a moving wall moving at the same speed as the flow velocity of the vertical wall. Allow the flow to flow in the free field.

As shown in Table 4, the governing equations are analyzed using the Navier-Stokes equation, and the turbulence model is a standard K-epsilon two equation provided by FLUENT, a commercial flow analysis software. The standard k-epsilon 2 equation model is used to derive the equation for calculating the pressure from the continuous equation to solve the pressure field. Semi Implicit Method for Pressure-Linked Equation Algorithm.

Condition Governing equation Continuity & Time averaged
Navier-Stokes equation Turbulence model Standard k-ε (2 equation) Pressure term SIMPLE algorithm

According to the experiment of the above modeling, the vortices generated by the flow are identified by the swirling strength, and the amount of vortex in each case is simulated.

As shown in Table 5, the swirling strength of the base model without the vortex suppression blade 20 is 766.67, whereas the swirling strength of 24 cases is 663.14. 20) less frequently than the base model without formation.

No. Swirling strength (S-¹) base 766.67 One 1429.21 2 3217.92 3 1358.52 4 2418.97 5 2192.49 6 2585.50 7 3380.04 8 2718.63 9 3088.09 10 1518.71 11 1419.91 12 1541.22 13 4375.47 14 4806.74 15 1505.82 16 1490.74 17 1461.86 18 1653.63 19 2824.29 20 2937.50 21 1218.26 22 663.37 23 673.38 24 663.14 25 1196.61 26 1219.74 27 1144.08

Therefore, as shown in Table 5, the smaller the swirling strength, the smaller the vortex, and thus the mesh characteristic. The signal-to-noise ratio is calculated by the following formula.

The main effect diagram for each factor using the signal-to-noise ratio (SN ratio) calculation result of each case is shown in FIG. 7, and the interaction action for each factor is shown in FIG. 8.

As described above, it can be seen that the length of the vortex inhibiting target 20 and the angle of the Z axis act as the most influential factor in the signal-to-noise ratio. It can be seen that the factor is sensitive to the amount.

Table 6 shows the degree of sensitivity of each factor to the amount of vortex in order of ranking.

level Length X axis angle Z axis angle diameter interval One 2488 1939 1396 2250 2143 2 2196 2206 1692 2087 2291 3 1390 1928 2984 1736 1640 responsiveness 1098 278 1586 515 651 ranking 2 5 One 4 3

Using the vortex generation factors derived from the comparison of the generated vortex flows based on the steady-state flow analysis, the optimal vortex control target shape was selected as shown in Table 7.

Control factor Selection value unit Length 14 mm X axis angle 15 Deg Z axis angle 0 Deg diameter 3 mm interval 3 mm

Analyzing the noise reduction effect according to the scale ratio (scale 1, scale 1.5, scale 2, scale 3, scale 4) of the eddy current suppressor 20 based on the selection value of Table 7 above (scale 1), FIG. 9 As can be seen, the noise reduction effect of scale 2 (compared to peak value of aerodynamic noise level for each frequency) is the largest compared to the base model (mud flap which is the end of railway vehicle).

Therefore, with reference to the graph of Figure 9 is the vortex suppression target 20 is a cylindrical shape having a length of 21 ~ 27mm, a diameter of 5 ~ 7mm, it is preferably formed spaced apart from each other at intervals of 5 ~ 7mm, It is preferable that 20 is formed so that it may be deflected by 10 to 20 degrees in one direction.

As shown in FIG. 10, in the inter-vehicle space of the conventional high-speed railway vehicle, a peeling phenomenon that flows through the wall surface of the front of the inter-vehicle space immediately at the end of the mud flap is generated and many vortices are generated.

As shown in FIG. 11, it can be seen that the flow of the fluid is changed by the vortex inhibiting target 20, and the fluid flowing by the vortex inhibiting target 20 flows along the feather shape, which sustains the peeling phenomenon. The effect is to reduce the amount of vortex and the pressure fluctuation, thereby reducing the noise.

Therefore, when the present invention is installed in the inter-vehicle space of the high-speed railway vehicle by the above experiment, the overall noise level of the aerodynamic noise generated in the inter-vehicle space is reduced by 3 dB or more, especially in the 100 ~ 630 Hz band, which shows a large eddy current. The production of is hindered and the noise source itself is greatly reduced.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: body 11: coupling part
20: vortex control feather 30: coupling member
31: first coupling groove 32: second coupling groove

Claims (6)

A plate-type body installed in the inter-vehicle space of the high-speed rail vehicle to reduce aero noise generated in the inter-vehicle space when the high-speed rail vehicle travels;
Aerodynamic noise reduction device of a high-speed railway, including; a plurality of vortex control target protruding toward the rear of the body.
The method of claim 1,
The body is formed of a plate,
The eddy current suppressor is a 21 ~ 27mm in length, 5 ~ 7mm in diameter cylindrical, aerodynamic noise reduction device of the high-speed railway is formed spaced apart from each other at intervals of 5 ~ 7mm.
3. The method of claim 2,
The eddy current suppression target is aerodynamic noise reduction device of the high-speed railway is formed to be deflected in one direction 10 ~ 20 °.
3. The method of claim 2,
The eddy current suppressor is aerodynamic noise reduction device of the high-speed railway is formed so as to be curved protruding end.
3. The method of claim 2,
The eddy current suppressor is aerodynamic noise reduction device of the high-speed railway is formed narrower toward the end.
The method of claim 1,
A coupling portion having a 'T' shape is formed at one end of the body, and a first coupling groove into which the coupling portion is inserted and coupled is formed at one side, and a second coupling groove is formed at the other side to which the end of the high speed railway vehicle is fitted. Aerodynamic noise reduction device of a high-speed railway comprising a coupling member.

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