JP2010271136A - Wind tunnel test equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide wind tunnel test equipment for reproducing a flow field between a fender and a vehicle without using a device for turning wheels such as a moving belt or causing the vehicle to be self-propelled. <P>SOLUTION: The wind tunnel test equipment 1 includes a reproducing means 3 of the flow field by a tracer flowing in accordance with a flow of a fluid flowing through a wind tunnel and the vehicle 2 having the wheels 5 and the fender 6. The reproducing means 3 of the flow field includes an ejector 9 provided between the wheels 5 and the fender 6 and having a plurality of spouts 9A and 9B formed, and a fluid supply device 8 for the tracer for supplying the fluid containing the tracer to the ejector 9. The fluid supply device 8 for the tracer is adjusted so that a flow rate of the fluid including the tracer may decrease from the spout 9A immediately above the wheel 5 toward the spout 9B immediately below the fender 6. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to wind tunnel experimental equipment, and more particularly to reproduction of a flow field between a vehicle wheel and a fender.

  In general, in a wind tunnel experiment for examining a fluid phenomenon around a vehicle during traveling, a flow field is reproduced by a tracer method using smoke. In addition, in order to reproduce the flow field around the wheels of the vehicle, as shown in FIG. 6A, a device for rotating wheels such as a moving belt that moves the lower part of the vehicle corresponding to the road at the same speed as the wind speed. Experiments have been carried out by reproducing the state close to the actual running by using the vehicle or running the vehicle. As a result of these experiments, the speed distribution assumed between the fender and the vehicle is, as shown in FIG. 6 (b), the speed immediately above the wheel becomes the maximum speed, the speed decreases toward the fender, and becomes 0 immediately below the fender. It is known to form a triangle. Moreover, about this speed distribution, the relationship between the distance from the wheel to the fender and the ejection speed is the relationship shown in FIG.

Patent Documents 1 to 3 disclose moving belts that move a portion under the vehicle corresponding to a road.
Patent Document 4 discloses a wheel receiver having a roller that rotates together with a wheel as a device for moving a portion under the vehicle corresponding to a road.

Japanese National Patent Publication No. 11-509926 JP 2004-198317 A JP 2004-77402 A JP 2001-324409 A

However, wind tunnel experimental equipment that reproduces a state equivalent to actual driving using a device that rotates wheels such as a moving belt and a wind tunnel experimental equipment that self-runs a vehicle are complicated in structure and require time to manufacture. Had the problem of being expensive.
For example, the inventions disclosed in Patent Document 1 to Patent Document 3 have a problem that a moving belt is required.
For example, the invention disclosed in Patent Document 4 has a problem that a wheel receiver having a roller that rotates with the wheel is required.

  The present invention has been made in view of such circumstances, and is a wind tunnel capable of reproducing a flow field between a fender and a vehicle without using a device that rotates wheels such as a moving belt or causing the vehicle to self-propel. The purpose is to provide experimental equipment.

In order to solve the above-mentioned problems, the wind tunnel test facility of the present invention employs the following means.
That is, the wind tunnel experimental facility according to the present invention is a wind tunnel experimental facility comprising: means for reproducing a flow field by a tracer that flows along with a flow of fluid flowing in the wind tunnel; and a vehicle having a fender and a wheel. The reproduction means includes a jet body provided between the fender and the wheel and formed with a plurality of jet ports, and a fluid supply device for a tracer that supplies a fluid including the tracer to the jet port. The fluid supply device for the tracer is adjusted so as to decrease the flow rate of the fluid including the tracer from the jet body directly above the wheel toward the jet body immediately below the fender.

  The actual speed distribution between the fender and the wheel is the maximum speed immediately above the wheel, and the speed decreases toward the fender, and is zero immediately below the fender. Therefore, the flow rate of the fluid including the tracer ejected from the ejection port installed immediately above the wheel is larger than the flow rate of the fluid including the tracer ejected from the ejection port installed immediately below the fender. Therefore, the flow field between the fender and the wheel can be reproduced without rotating the wheel. Therefore, a device for rotating wheels and a device for actually running a vehicle are not required, and the wind tunnel experimental facility is simplified. Accordingly, it is possible to shorten the installation time of the wind tunnel experiment facility and the installation cost.

  In the wind tunnel experimental facility of the present invention, the jet body is provided with a wire mesh having different opening ratios so as to be dense from the wheel toward the fender.

  When the fluid containing the tracer passes through the portion where the opening ratio of the wire mesh is dense, the flow rate of the fluid is reduced as compared to when passing through the portion where the opening ratio of the wire mesh is coarse. In addition, the actual speed distribution between the fender and the wheel is the maximum speed immediately above the wheel, and the speed decreases toward the fender, and is zero immediately below the fender. Therefore, since the opening ratio of the wire mesh provided on the ejector was changed from coarse to dense from the wheel to the fender, the actual distance between the fender and the vehicle was increased without increasing the number of ejectors. It is possible to reproduce the flow field that approximates the flow of

  In the wind tunnel experimental facility of the present invention, the total width of each jet port formed in the jet body is substantially equal to the width of the wheel, and the width of each jet port is substantially equal. And

  Since the fluid containing the tracer uniformly divided over the width of the wheel is ejected from the jet nozzle, the flow field in the entire width of the wheel can be reproduced.

  The vehicle in the wind tunnel experimental facility of the present invention is characterized in that an endless track band is used as the wheel.

  Since the flow between the endless track zone and the fender can be reproduced, it is possible to reproduce the dust wound up by the endless track zone.

  According to the present invention, the plurality of jets of the jetting body installed between the fender and the wheel are adjusted so as to reduce the flow rate in order from the jet right above the wheel toward the jet right below the fender. Since the fluid including the tracer is guided, the flow field between the fender and the wheel can be reproduced without rotating the wheel. Therefore, a device for rotating wheels and a device for actually running a vehicle are not required, and the wind tunnel experimental facility is simplified. Accordingly, it is possible to shorten the installation time of the wind tunnel experiment facility and the installation cost.

It is a side view of the wind tunnel experimental equipment which concerns on 1st Embodiment of this invention. It is a perspective view of the ejection body shown in FIG. It is a graph which shows the relationship between the distance from the endless track body shown in FIG. 1 to a fender, and the assumed ejection speed of the gas containing the smoke from an ejection body. The jet body which concerns on 2nd Embodiment of this invention is shown, (a) is a perspective view, (b) is a front view of the metal mesh which a jet body has. It is a graph which shows the relationship between the distance from an endless track body to a fender, and the jet velocity of the gas containing the smoke from a jet body about 2nd Embodiment of this invention. The conventional wind tunnel experiment equipment is shown, (a) is the schematic which showed the principal part, (b) is the figure which showed the speed distribution between a wheel and a fender when a wheel is driven. It is a graph which shows the relationship between the distance from a wheel to a fender in case the wheel shown in FIG. 6 is driven, and an assumed ejection speed.

Embodiments according to the present invention will be described below with reference to the drawings.
[First Embodiment]
FIG. 1 shows a side view of a wind tunnel experimental facility 1 according to the first embodiment of the present invention.
The wind tunnel experimental facility 1 includes a vehicle 2 and a reproduction means 3 for a flow field of smoke (tracer) flowing along with a flow of gas (fluid) flowing in the wind tunnel.
The vehicle 2 has an endless track zone (wheel) 5 and a fender 6 located at an upper part spaced apart from the endless track zone 5.
The flow field reproduction means 3 includes a smoke ejection device (not shown), a tracer fluid supply device 8, an ejection body 9, and a blower 10.
The tracer fluid supply device 8 includes flow meters 11A and 11B, flow rate adjusting valves 12A and 12B, a branch pipe 13, branch pipes 14A and 14B, and vinyl pipes 15A and 15B.

The branch pipe 13 provided in the tracer fluid supply device 8 is connected from the smoke ejection device via the blower 10. Two branch pipes 14 </ b> A and 14 </ b> B are connected to the branch pipe 13. Flow control valves 12A and 12B are connected to the branch pipes 14A and 14B in order to adjust the flow rate of the gas containing smoke. The flow meters 11A and 11B connected to the flow control valves 12A and 12B can measure the flow rate of the gas containing smoke adjusted by the flow control valves 12A and 12B. The downstream sides of the flow meters 11A and 11B are connected to a distributor (not shown) by vinyl tubes 15A and 15B that are easy to handle. Vinyl pipes 15A and 15B are connected to the distributor as many as the number of divided lattices in the ejection openings 9A and 9B of the ejection body 9.
The ejection body 9 is installed between the front part of the endless track 5 of the vehicle 2 and the fender 6 so that the opening surface is on the upstream side of the flow field.

Next, the ejection body 9 which concerns on 1st Embodiment is demonstrated using FIG.
The jet body 9 includes a jet port 9A having a plurality of grid portions 30A and a jet port 9B having a plurality of grid portions 30B. The jet outlets 9A and 9B form a rectangular parallelepiped having a lateral width equivalent to the width of the endless track 5. The jet outlets 9A and 9B are equally divided in a lattice shape in the width direction of the endless track 5. The plurality of grid portions 30A and 30B are arranged in a horizontal row. Vinyl pipes 15A and 15B branched from the flow meters 11A and 11B are connected to the plurality of lattice portions 30A and 30B.

  A gas containing smoke generated by the smoke generator is introduced into the branch pipe 13 by the blower 10. The flow rate of the gas containing smoke introduced into the branch pipe 13 is adjusted by the flow rate adjusting valves 12A and 12B via the branch pipes 14A and 14B. The gas containing the smoke whose flow rate is adjusted is led to the vinyl pipes 15A and 15B via the flow meters 11A and 11B. The derived gas containing smoke is introduced into the lattice portions 30A and 30B of the jet outlets 9A and 9B by a distributor connected to the vinyl pipes 15A and 15B. The gas containing the introduced smoke passes through the inside of the jet outlets 9A and 9B and is jetted from the surface of the jetting body 9 that is open.

FIG. 3 shows the relationship between the distance from the endless track zone 5 to the fender 6 in the first embodiment and the ejection speed simulated by the gas containing smoke.
In the figure, the vertical axis represents the distance between the endless track 5 and the fender 6, and the horizontal axis represents the ejection speed of the gas containing smoke ejected from the opening surface of the ejection body 9. The actual ejection speed between the endless track zone 5 and the fender 6 becomes a maximum speed immediately above the endless track zone 5 and decreases toward the fender 6, and becomes 0 immediately below the fender 6. Therefore, the actual ejection speed between the assumed endless track 5 and the fender 6 is indicated by a broken line in FIG. The ejection speed between the endless orbit zone 5 and the fender 6 is simulated by changing the flow rate of the gas containing smoke supplied to the ejection ports 9A and 9B. The gas containing the smoke ejected from the ejection port 9A installed on the side where the ejection speed is fast is larger than the gas containing the smoke ejected from the ejection port 9B installed on the side where the ejection speed is slow By adjusting so that the gas containing smoke is ejected, the ejection speed is simulated. Therefore, the flow rate adjusting valve 12A adjusts the flow rate of the gas containing the smoke supplied to the jet port 9A installed just above the endless track 5 to 75% of the total flow rate generated by the smoke generator. Adjusted. Further, a flow rate of 25% with respect to the total flow rate generated by the smoke generator is supplied to the jet port 9B immediately below the fender 6 by adjusting the flow rate adjustment valve 12B. Since the flow rate of the gas containing the smoke ejected from the ejection ports 9A and 9B is changed by changing the flow rates supplied to the two ejection ports 9A and 9B, the simulated ejection speed is indicated by a solid line in FIG. A stepped shape is formed.

As described above, the wind tunnel experimental facility according to this embodiment has the following effects.
Since gas containing smoke whose flow rate is adjusted is ejected from the ejection ports 9A and 9B of the ejection body 9 installed between the fender 6 and the endless orbit zone 5, there is a gap between the fender 6 and the endless orbit zone 5. The flow field can be reproduced. This eliminates the need for a device for rotating the endless track 5 and simplifies the wind tunnel experimental facility 1. Therefore, the installation time of the wind tunnel experimental equipment 1 can be shortened and the installation cost can be reduced.

  In addition, since the jet outlets 9A and 9B of the jet body 9 eject gas containing smoke that is uniformly divided over the width of the endless track zone 5, the flow field in the entire width of the endless track zone 5 is reproduced. Can do.

In addition, although this embodiment demonstrated using smoke as a tracer, this invention is not limited to this, It is good also as gas, such as methane. In the case of using gas, several concentration measurement points are provided in advance on the opening side of the ejection body 9, and the flow field may be reproduced by measuring the gas concentration at each concentration measurement point with a gas chromatograph. .
In addition, the smoke that is the tracer has been described as being generated by the smoke generator together with the gas that is the fluid, and the flow rate is adjusted by the flow rate adjusting valves 12A and 12B. You may throw in in any position between the opening surfaces.
Furthermore, although the jet nozzles 9A and 9B have been described as two, the number may be further increased. By increasing the number, it is possible to further simulate the ejection velocity that approximates the current flow.
Further, the jet outlets 9A and 9B of the jet body 9 have been described as being adjusted so that the flow rate of the gas containing smoke decreases in order upward from the endless track band 5 toward the fender 6, but the present invention is not limited to this. However, the flow field in the width direction of the endless track zone 5 may be reproduced as the ejector 9 having the jet outlets 9A and 9B in the width direction of the endless track zone 5.
Moreover, although it demonstrated using the endless track zone 5, it is good also as a wheel.

[Second Embodiment]
Next, the ejection body 9 and the wire mesh 20 according to the second embodiment of the present invention will be described with reference to FIGS. 4 (a) and 4 (b).
The jet body 9 and the wire mesh 20 according to the present embodiment are similarly installed in the wind tunnel experimental facility 1 described in the first embodiment. Therefore, the description about the common part with 1st Embodiment is abbreviate | omitted.
As shown in FIG. 4A, the ejection body 9 has two ejection ports 9 </ b> A and 9 </ b> B, and a wire mesh 20 is installed on the opening surface of the ejection body 9. As shown in FIG. 4 (b), the wire mesh 20 has an opening ratio from coarse to dense from the endless track 5 toward the fender 6.
FIG. 5 shows the relationship between the distance from the endless track zone 5 to the fender 6 and the ejection speed simulated by the gas containing smoke in the second embodiment. Also in this figure, as in FIG. 3, the vertical axis indicates the distance between the endless track 5 and the fender 6, and the horizontal axis indicates the ejection speed of the gas containing smoke ejected from the opening surface of the ejection body 9. ing.
In the same figure, as in FIG. 3, the flow rate of the gas containing smoke supplied to the jet outlet 9A immediately above the endless track 5 is 75% of the total flow rate generated by the smoke generator. It is adjusted by the regulating valve 12A. Further, a flow rate of 25% with respect to the total flow rate generated by the smoke generator is supplied to the jet port 9B immediately below the fender 6 by adjusting the flow rate adjustment valve 12B. Further, since the wire mesh 20 having different opening ratios shown in FIG. 4B is installed on the opening surface of the jetting body 9, the jet velocity of the stepped gas shown by the solid line in FIG. 5, the shape is shown by a solid line. Therefore, by installing the wire mesh 20 having different opening ratios on the opening surface of the ejection body 9, the stepwise ejection speed shown by the solid line in FIG. 3 according to the first embodiment is changed to the actual ejection speed shown by the broken line. It can be simulated to an approximate shape.
When the gas containing smoke passes through a portion where the opening ratio of the wire mesh 20 installed in the ejection body 9 is dense, the flow rate at which the opening ratio of the wire mesh 20 is ejected compared to when passing through a rough portion. Decrease. In addition, the actual velocity distribution between the endless track zone 5 and the fender 6 has a maximum speed immediately above the endless track zone 5 and decreases toward the fender 6, and becomes 0 immediately below the fender 6. Therefore, by changing the aperture ratio of the wire mesh 20 provided in the ejection body 9 from the coarse track to the fender 6 from the coarse track zone 5 to the fender 6, the unlimited track zone without increasing the number of the outlets 9A and 9B. Reproduction approximate to the actual flow between 5 and the fender 6 is possible.

  In addition, the adjustment of the flow rate of the gas containing smoke by the flow rate adjusting valves 12A and 12B and the information on the opening ratio of the wire mesh 20 can be obtained by a test operation.

As described above, the wind tunnel experimental facility 1 according to the present embodiment has the following operational effects.
The speed at which the gas containing smoke is ejected from the ejection ports 9A and 9B is changed by passing through the wire mesh 20 having different opening ratios installed in the ejection body 9. Therefore, it is possible to simulate a speed approximating the actual ejection speed without increasing the number of the ejection ports 9A and 9B by the passage of the gas containing smoke through the wire mesh 20 whose aperture ratio changes. Therefore, a reproduction approximating the actual flow between the fender 6 and the endless track 5 can be performed.

  In the present embodiment, the vehicle 2 has been described as equivalent to a real vehicle, but the present invention is not limited to this and may be a model vehicle.

1 Wind tunnel test equipment 2 Vehicle 3 Flow field reproduction means 5 Endless track (wheel)
6 Fender 8 Tracer fluid supply device 9 Spout body 9A, 9B Spout

Claims (4)

A means for reproducing the flow field by a tracer that flows along with the flow of fluid flowing in the wind tunnel,
A vehicle having a fender and wheels;
In the wind tunnel experimental facility equipped with
The flow field reproduction means includes a jet body provided between the fender and the wheel and formed with a plurality of jet ports, and a fluid supply device for a tracer that supplies a fluid including the tracer to the jet body. With
Wind tunnel experiment characterized in that the fluid supply device for the tracer is adjusted so as to decrease the flow rate of the fluid containing the tracer from the jet outlet immediately above the wheel toward the jet outlet immediately below the fender. Facility.   The wind tunnel experimental facility according to claim 1, wherein the jet body is provided with a wire mesh having different opening ratios so as to be dense from the wheel toward the fender.   The total width of each of the jet ports formed in the jet body is substantially equal to the width of the wheel, and the width of each jet port is substantially equal. Item 3. Wind tunnel test equipment according to Item 2. The wind tunnel experimental facility according to any one of claims 1 to 3, wherein the vehicle uses an endless track as the wheel.

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