KR100367627B1 - model train test equipment - Google Patents

Abstract

The present invention relates to a train model test apparatus for aerodynamic tunnel design,

An object of the present invention is to realize high-speed launching speed and driving stability, and to minimize noise when measuring the micro-pressure wave by separating the firing sound, and to calculate data for deriving accurate train head shape. It is to provide a train model test apparatus for tunnel aerodynamic design.

Specific means of the present invention for achieving the above object;

A train model propulsion unit in which a launch tube of a tubular body in which a dump tank for excluding a blast wave is formed is communicatively coupled to an injection port of a pressure vessel having a rupture film;

A train model in which a single steel wire is guided by a guide mechanism formed as a guide structure and has a streamlined frontal head as an axisymmetric structure;

A tunnel model as a test area in which a microbarometer and a plurality of pressure sensors are installed to measure pressure changes and microbarometer waves and a hood is formed at the inlet side;

It is achieved by providing a train model test apparatus for aerodynamic design of a railway tunnel, which consists of a train model braking unit in which a braking tube is configured to brake by surface friction.

Description

Model train test equipment

The present invention relates to a train model test apparatus for aerodynamic design of a railway tunnel, and more particularly, as a tester for designing a tunnel aerodynamic design and aerodynamic design for reducing a micro-pressure wave, and a design for optimizing a frontal head and a cross-sectional area of a vehicle. The 1-wire guide system is applied and air launching device is applied as a launching mechanism to realize high-speed launching speed and driving stability, and the noise can be minimized by measuring the sound pressure by separating the sound. The present invention relates to a train model test apparatus.

In general, the tunnel driving train model test apparatus detects various aerodynamic phenomena generated when a railroad vehicle traveling at high speeds passes through a tunnel, and based on this, optimally designes the internal cross section of the tunnel and the shape and cross-sectional area of the train head. As a tester used to develop measures to reduce micro-pressure waves,

As a configuration requirement of such a test apparatus, a launching apparatus capable of propelling a train model at a real speed in a short acceleration section is required, and then a braking apparatus is required to settle the tunnel model and the train model corresponding to the test section without damage. It should be equipped with a guide mechanism so as not to derail the train model as a whole.

In addition, the train model test apparatus should be able to finely adjust the firing speed of the train model, be able to meet the operating range of the high-speed railway at a short test length, and there should be no influence due to air jet or launch device noise in the test area. However, these noises shall be noises which can be separated from the micropressure wave during the test.

On the other hand, such a test apparatus is being developed and used in France, Japan, and the Netherlands, which used high-speed railway,

The propulsion method of the train model in the test apparatus of each country is widely known, such as the catapult method, gun powder method, air-pneumatic (air gun) method, wheel rotation method.

Here, the slingshot method can be obtained up to a relatively low speed of 55 m / s (198 km / h), the speed of more than 300 km / h can obtain a speed of 160 m / s by dry powder or pneumatic propulsion, the dry powder method Has very high acceleration, and it is difficult to adjust compared to the pneumatic propulsion under various test conditions (train weight and firing speed, etc.), and the explosion sound of the dry powder acts as a big obstacle in measuring the micropressure wave. .

The firing lubrication method (launched between close-rotating wheels) proposed by the Japan R & D Center is to propel a train model by rotating four firing lubrication with four motors each. Therefore, it is difficult to adjust the firing speed and the maximum firing speed remains at 400 km / h.

However, by applying a one-line guide method as a guide method of the train model because of the firing lubrication method, a more accurate shape of the front of the train head can be obtained.

The test equipment presented by the French Institute of Railway Technology is to stop the train immediately after entering the tunnel during the test by fixing the train model to the end of the piston operated by pneumatic pressure. The maximum firing speed is 200km / h. will be.

The test equipment of the aerospace research institute of the Netherlands can achieve a speed of 500km / h as an ultra high speed, but the two head guides are applied to guide the train model. Because of the inaccurate shape of, it is difficult to obtain actual test data.

Therefore, the present invention was devised to solve the general problems of the conventional train model test apparatus presented in each country,

An object of the present invention is to realize high-speed launching speed and driving stability, and to minimize noise when measuring the micro-pressure wave by separating the firing sound, and to calculate data for deriving accurate train head shape. It is to provide a train model test apparatus for tunnel aerodynamic design.

Specific means of the present invention for achieving the above object;

A train model propulsion unit in which a launch tube of a tubular body in which a dump tank for excluding a blast wave is formed is communicatively coupled to an injection port of a pressure vessel having a rupture film;

A train model in which a single steel wire is guided by a guide mechanism formed as a guide structure and has a streamlined frontal head as an axisymmetric structure;

A tunnel model as a test area in which a microbarometer and a plurality of pressure sensors are installed to measure pressure changes and microbarometer waves and a hood is formed at the inlet side;

It is achieved by providing a train model test apparatus for aerodynamic design of a railway tunnel, which consists of a train model braking unit in which a braking tube is configured to brake by surface friction.

1 is an overall configuration diagram of a train model test apparatus according to the present invention

2 is a configuration of the train model test apparatus according to the present invention, the train model propulsion unit

3 is a schematic view showing the operating state of the train model propulsion unit in the train model test apparatus according to the present invention;

4 is a graph showing the performance analysis for the design and manufacturing of the train model test apparatus according to the present invention

Figure 5a is a state diagram showing the problem in the train model test unit, train model test unit

Figure 5b is an operation state diagram of the improved train model of the present invention of Figure 5a

6 is a configuration of the train model guide mechanism in the train model test apparatus according to the present invention;

FIG. 7 is a block diagram of part A of FIG.

8 is a cross-sectional view of the tunnel model in the train model test apparatus according to the present invention

9 is a configuration of the tunnel model and train model braking unit in the train model test apparatus according to the present invention.

10 is a configuration diagram of a data acquisition system of a train model test apparatus according to the present invention.

◑ Explanation of symbols for main parts of drawing◑

1: Train model promotion unit 2: Train model 3: Tunnel model

4 train model braking unit 11 compression container 12 launch tube

13: dump tank 21: guide mechanism 22: train model

31 pressure sensor 32 microbarometer 33 hood

111 rupture film 131 sealing means 211 steel wire

212,212 ': Steel wire fixing sphere 213: Vise fixing ring 214: Steel wire clamp

221, 222: front and rear head E: train model test apparatus

Hereinafter, preferred embodiments of the present invention will be described in detail by the claims.

1 is an overall configuration diagram of a train model test apparatus according to the present invention, FIG. 2 is a configuration diagram of a train model propulsion unit in the train model test apparatus according to the present invention, and FIG. 3 is a train model test apparatus according to the present invention. In Figure 4 is a schematic diagram showing the operating state of the train model propulsion unit, Figure 4 is a graph showing the performance analysis for the design and manufacturing of the train model test apparatus according to the present invention, Figure 5a is a train model test apparatus, train model promotion Figure 5b is a functional state diagram showing the problem of the part, Figure 5a is a functional state diagram of the improved train model propulsion unit of the present invention of Figure 5a, Figure 6 is a configuration diagram of the train model guide mechanism in the train model test apparatus according to the present invention FIG. 7 is a partial configuration diagram of FIG. 6, FIG. 8 is a cross-sectional view of a tunnel model in the train model test apparatus according to the present invention, and FIG. 9 is a tunnel model in the train model test apparatus according to the present invention. And train the model and structure of the ET Fig, 10 is a look at the configuration state as a data acquisition system configuration of a thermal model testing apparatus in accordance with the present invention;

As a scale model of a real railway vehicle and a tunnel, it is composed of a train model propulsion unit 1, a train model 2, a tunnel model 3 as a test area, and a train model braking unit 4.

Here, in order to implement the test apparatus according to the present invention, the wave diagram and the position of the train traveling along this pattern should be adjusted according to the reduced time and length scale, and the following conditions were considered.

First, the ratio of the train speed V to the speed of sound a is satisfied, which means that the Mach number M = V / a should be the same in the scale experiment.

Second, the tunnel-to-train length ratio must be the same, and a third condition is required to reproduce the strength of the pressure wave, which must have the same blockage ratio B = A _train / A _tunnel .

Where A _train is the effective area of the train and A _tunnel is the internal area of the tunnel.

In addition, because the test must be adjusted to the Mach number, the train speed of the scale model should be taken as the actual value without being controlled by the scale.

In this development, the train model was chosen to be 58 mm in diameter, corresponding to 1/60 scale.

On the other hand, the Reynolds number effect cannot be overlooked as the friction decreases as the scale decreases. The direct effect of the Reynolds number attenuates the pressure waves propagating in the tunnel, and this Reynolds The impact is partly compensated by the higher surface roughness of the actual tunnel and the use of smooth walls for the tunnel scale model.

This evidence is, as is known from Matsuo et al. [1997], that the damping at model scale is less than 10% compared to a 5% frictional force damping in the case of the scale, and is accepted for the scale prediction in the pressure relief measurements. It was considered to be acceptable.

In the test apparatus E according to the present invention based on the above description, the train model propulsion unit 1 is filled with a working pressure as shown in Figs. 111) Mylar membrane (Mylar membrane) is configured by coupling the firing tube 13 having the dump tank 13 to the compression container 11 is formed, the coupling,

Here, as a method for pushing the train model (2), as described above, the catapult method [Pope, 1991], the gun powder method [Dayman, 1991], the air-pressure (air gun) [Takayma, 1995] method, Wheel rotation method [Maeda, 1993] and the like are known, the design speed of the test apparatus according to the present invention is at least 111 m / s, so the slingshot method is not suitable, the gun power propulsion has a very large acceleration as described above It is difficult to adjust under various test conditions (train weight and firing speed) and additional safety problems cannot be considered. As the most preferable propulsion method, the test apparatus of the present invention adopts an air-fired method (air gun method).

In addition, the launch tube 12 is inserted into the compression vessel 11, the other side is inserted into the structure in communication with the launch port and the dump tank 13 is formed at one end, such a launch tube 12 is a train model It has a structure for excluding the influence of blast wave generated at the acceleration of (2),

If the blast wave exclusion structure is described in detail;

As shown in FIG. 5A, the air jet generated as the air is compressed in front of the train while accelerating the train model 2 is ejected from the opening of the launch tube 12, and the jet flow is caused by the internal pressure of the tunnel model 3. It can be seen that the residual back pressure (P on FIG. 5A) in the tube 12 becomes greater than atmospheric pressure (P _atm on FIG. 5A) when the back of the train leaves the launch tube.

At this time, the blast wave (blast wave) is generated, this blast wave is a high-speed jet flow to the spherical shock wave to hit the test tunnel inlet, thereby affecting the internal pressure of the test tunnel. The blast wave generated by such a back pressure can be completely removed by reducing the residual back pressure below atmospheric pressure as shown in FIGS. 3 and 5b.

In addition, as described above, the dump tank 13 formed at one end of the launch tube 12 has a tunnel model 3 in which a blast wave is a test part when the train model 2 is fired from the launch tube 12 to be accelerated. As shown in FIG. 2, a plurality of through holes (preferably having an opening ratio of 80%) are formed in communication with the inner holes, and the injection holes are closed by the sealing means 131 (for example, paper tape, etc.). It is sealed so that it can be a vacuum by vacuum pump at high speed.

At this time, at least 400 km / h of firing speed should be reached according to the requirements of the test apparatus. As described above, in the present invention having a train model of 1/60 scale, the diameter of the launch tube 12 is 60.5 mm long. Was set to 4.3 m, and the compression vessel ((11) driver) was set to 1.5 liter, and based on this, the length and weight of the train model (2), which will be described later, were determined.

At this time, when the train model is launched from the launch tube 12, the residual back pressure at which the air jet is not released from the exit of the launch tube 12 when the back of the train exits the launch tube 12 should be 0.8 atm or less, and behind the train. If the back pressure changes with the adiabatic process and the pressure in front of the train is kept at atmospheric pressure (and neglects the wall friction), the acceleration a is expressed at position x at the tip of the back of the train model in the launch tube.

Where P _d is the pressure of the driver, P _atm is the atmospheric pressure [N / m ² ], Vd is the compressed container volume [m ³ ] A is the cross-sectional area of the launch tube [m ² ], m is the Mass [kg], superscript v is 1.4 for air.

In addition, the numerical integration of Equation (1) is to terminate the numerical integration when the value in the large parentheses of Equation (2) at any point of the tube satisfies (0.8-1) P _atm / P _d , the numerical value according to the Integral applied Simpson's Rule.

Thus, the results of the above performance prediction are as shown in the graph shown in Figure 4, based on this the weight of the train model was applied to 0.19 kg ~ 0.35 kg, the back pressure is below 0.8 atm according to the pressure adjustment of the compression vessel The firing speed can be adjusted up to 600 km / h.

On the other hand, the train model (2) is composed of a train model 22 which is guided to the guide mechanism 21,

The train model 22 is formed as an MC material in a body formed by compressing a paper in a tubular form (paper tube) so that its mass is minimized in order to maximize the firing speed. The streamlined frontal head 221 and the straight head-shaped rear head 222, in which the treated guide hole is formed, are integrally coupled.

The guide mechanism 21 extends out of the exit of the model tunnel 3 to be described later at the starting point of the launch tube 12 so that the train does not hit the wall or proceed in the other direction. In that,

Such steel wire 211 is fixed by the first and second steel wire fasteners (212,212 ') in which a plurality of bolts are inserted into the press plate vise that is laminated as shown in FIGS. In the front of the fixture 212, in order to set the correct center position of the steel wire 211 is formed a positioning hole in the center in the form of a disc, an ellipsoidal through-hole is formed at a point divided into three around the positioning hole The fixing ring 213 is fixed to be installed in the shape of the receiving tube 12 in the inner diameter, the exit steel wire fixture 212 'of the tunnel model 3 so as to tension the steel wire 211 as necessary. As a structure for horizontally moving by a worm gear, which is fixed to the steel wire tensioning tool 214 using the driving motor as a driving source, the train model 2 has a steel wire 211 through guide holes of the front and rear head parts 221 and 222. Penetrated and guided by liner Will.

In addition, the tunnel model 3 has a form in which the actual tunnel is scaled as shown in FIGS. 8 to 9, but the pressure sensor 31 has a predetermined interval (interval shown in the drawing) as a roof portion. It is installed, the hood 33 for reducing the micro-pressure wave is formed integrally at the inlet side, the micro-pressure wave meter 32 is installed at the point of the 45 degree angle outside the outlet,

The microbarometer 32 is measured at a position of 20 mm above the ground at a distance of 0.333 m from the tunnel exit, and the pressure sensor ((31) product name: 8510B-1) has a dynamic pressure range of 6.9 kPa and a resonance frequency of 55 kHz. For the measurement of microbarometric waves, Rion's XN-12A (constant sensitivity characteristic of 0.2 to 1 kHz) for railroad was applied. (Maximum range is 2 kPa.)

At this time, the signal detected through the microbarometer 32 was dataized by the data acquisition system of the present invention shown in FIG.

The measurement of this data acquisition system is actively initiated by the photo sensor in front of the tunnel entrance, measuring the train speed together (the photo sensor is located at 1.2 m in front and behind the tunnel, respectively). The Endevco pressure sensor model 8510B-1 was continuously recorded at multiple locations.

In addition, amplification was performed in a DC dynamic strain amplifier (MINEBEA model NMB DAS-406B) with a data acquisition of 200 kHz, followed by low pass filtering, and a device for converting an analog signal into a digital signal (preferably NI (Applying to National Instrument's High-speed A / D Converter model PCI-MI0-16E-1.) And data acquisition software LabVIEWTM were mounted on a computer to acquire data.

Finally, the train model braking unit 4 is composed of a braking tube 41 located on the exit side of the tunnel 3, as shown in FIG.

This is the braking of the high-speed train model (2) by using the surface friction force, take a tubular shape of one side is open, but the sponge material is applied as its material, the tube diameter is at least smaller than the diameter of the train model On the other side, the through-hole is formed so that the above-described steel wire penetrates.

Here, the braking tube 41 has a length of 2m, and the length setting is for the train model 2 to be completely braked, and the necessary deceleration a _d during braking in the braking tube 41 is v _2. -v ₁ = 2a _d S. As can be seen from this equation, when the deceleration distance is 2m, it can be seen that the deceleration of 711g is required when the train model 2 is launched at a speed of 600 km / h. g is 9.81 as the acceleration of gravity.)

Therefore, in the train model test apparatus according to the present invention divided into four parts as described above, the internal pressure of the launch tube 12 is removed after the rupture film of the compression vessel 11 filled with air pressure is removed in consideration of the desired speed. When it is 0.8 atm, the train model 2 accommodated in the launch tube is fired through the sealing means of the dump tank 13, and in the present invention, as described above, the blast wave is designed so as not to affect the test area. Therefore, the test can be accurate.

Thereafter, the train model 2 is guided to the single steel wire 211 of the guide mechanism 21 and passes through the tunnel model 3 at a high speed, whereby each pressure sensor 31 and the microbarometer 32 Air pressure fluctuations and micro-pressure wave data are measured, and braking of the train model 2 is performed by surface friction on the inner wall of the braking tube 41.

Based on the various data obtained through the test, the tunnel internal area, the shape and cross-sectional area of the front head of the train are optimally designed, and basic data are provided in developing a hood for reducing micro-pressure waves.

In the data obtained in the test apparatus of the present invention, the pressure measurement error is about 35 Pa, and the train speed has a deviation within 0.1 m / s,

In the tunnel model of 8.34 m ((3) scale 0.5 km), the train speed is reduced by about 2% while the train reaches the entrance to the tunnel, which is mainly due to the friction of the steel wire. ,

In order to compare to other tunnel specifications or pressure damping measurements, the data must be compared on the same basis, i.e. at the train speed, so a target speed of around 1% of the train model (2) is usually obtained in about three launches. The speed difference is a pressure deviation of 2% from the target value.

On the other hand, the train model test apparatus according to the present invention for driving a train at a specified speed to calculate a variety of data is applicable to the development of rockets, bullet trains, maglev trains.

As described above, the train model test apparatus according to the present invention can be applied to a bullet train and a rocket test as well as a conventional high-speed rail vehicle by implementing a firing speed of up to 600 km / h, thereby expanding the range of application and existing air pressure emission. The accuracy of the train head can be ensured by conducting tests with the correct frontal head shape using the one wire guidance system, which was a challenge in the device. It is advantageous to obtain accurate air pressure fluctuations in the tunnel and micro-pressure wave data at the tunnel exit.

In addition, the stability of the train model is enhanced by expanding and maintaining the steel wire as much as possible with steel wire fixtures and tension balls, and accurate test data can be obtained because other noise is not detected when measuring the micro-pressure wave by the automation of the data acquisition system and the separation of the firing sound. will be.

Claims (6)

A train model propulsion unit in which a launch tube of a tubular body in which a dump tank for excluding a blast wave is formed is communicatively coupled to an injection port of a pressure vessel having a rupture film; A train model in which a single steel wire is guided by a guide mechanism formed as a guide structure, and has an anterior- and posterior head of a streamlined shape as an axisymmetric structure; A tunnel model as a test area in which a microbarometer and a plurality of pressure sensors are installed to measure pressure changes and microbarometer waves and a hood is formed at the inlet side; In the train model test apparatus comprising a train model braking unit in which a braking tube is configured to brake by surface friction, the guide mechanism of the train model includes a single steel wire extending outward from the start point of the launch tube and the exit of the tunnel model. And a first and second steel wire fixing tool in which a plurality of bolts are inserted into a press plate vice which is formed as a layer as a fixing means of the steel wire. delete The train model test apparatus according to claim 1, wherein the model main body of the train model is formed of a branch pipe to minimize its own mass. The train model testing apparatus according to claim 1, wherein the dump tank is formed as a structure sealed by a sealing means. The train model test apparatus according to claim 1, wherein a disk-shaped vice fixing ring having a positioning hole is provided to set the center position of the steel wire in front of the first steel wire fixing tool. 2. The train model test apparatus according to claim 1, wherein the second steel wire fixing tool is fixedly coupled to the steel wire tension tool which performs horizontal movement as a means for tensioning the steel wire.