JP6993311B2 - Boundary layer control device and wind tunnel test device - Google Patents

Description

The present invention relates to a boundary layer control device and a wind tunnel test device.

For example, a wind tunnel test device is known as a device for evaluating aerodynamic performance of an automobile or the like. The wind tunnel test device includes a wind tunnel body on which the vehicle as a test object is placed, a blower that blows wind into the wind tunnel body toward the vehicle, and a belt conveyor-shaped ground plate for simulating the running state of the vehicle. , Is mainly provided.

In the wind tunnel test device as described above, it is general that the automobile is not actually driven but the traveling state is simulated by the rotation of the ground plate. In this case, a boundary layer is formed in the air flow between the floor of the automobile and the floor surface of the wind tunnel test device. As the boundary layer develops, the air flow below the vehicle slows down. As a result, the test results may be affected. As a device for controlling the behavior of such a boundary layer, for example, the device described in the following Patent Document 1 is known.

In the apparatus according to Patent Document 1, a suction duct for sucking the boundary layer is formed on the floor surface of the wind tunnel main body (air passage). At the upstream end of the suction duct, a flat air guide portion at an angle with respect to the floor surface is provided. The flow of the boundary layer guided through the air guide is sucked below the floor surface by the suction duct. As a result, it is said that the boundary layer does not affect the mainstream side.

Japanese Unexamined Patent Publication No. 2009-156695

However, in the device described in Patent Document 1, the air flow through the air guide portion suddenly changes its direction toward the suction duct and flows into the suction duct. Therefore, an unstable vortex flow that fluctuates with time is generated in the suction duct. When a time-varying vortex flow is generated, the flow rate of the air sucked by the suction duct fluctuates unsteadily. As a result, the flow of mainstream components other than the boundary layer may be affected, and an accurate wind tunnel test may not be possible.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a boundary layer control device and a wind tunnel test device capable of further reducing the influence of the boundary layer.

According to the first aspect of the present invention, the boundary layer control device is a boundary layer control device that sucks in the boundary layer formed by the friction between the blown air and the floor surface, and is below the floor surface. A suction flow path having an upstream side wall surface extending along the suction direction while sucking air in the suction direction which is a direction away from the floor surface, and a direction in which the air is blown from the floor surface. It bends and extends in the suction direction toward the downstream side in the ventilation direction and is connected to the suction flow path, and is connected to the upstream guide surface located on the upstream side in the ventilation direction and the downstream side in the ventilation direction. The connecting flow path having the downstream side guide surface to be located and the upstream side guide surface extending from the end portion of the upstream side guide surface on the suction flow path side to a predetermined position so as to extend below the floor surface, the said. It is provided with a rectifying surface that rectifies the flow of air by extending in the suction direction so as to recede from a predetermined position to the upstream side in the blowing direction.

According to this configuration, the boundary layer flowing along the floor surface is smoothly guided along the upstream guide surface and the downstream guide surface of the connecting flow path, and then sucked below the floor surface by the suction flow path. Will be done. This makes it possible to smoothly separate the mainstream flowing along the floor surface from the boundary layer. Further, it is possible to reduce the influence of the stagnation pressure (negative pressure) generated when the boundary layer is sucked downward through the suction flow path. This makes it possible to distribute the mainstream more stably. In addition, since a rectifying surface is formed between the downstream end of the upstream guide surface and the upstream side wall surface of the suction flow path, the downward flow along the upstream guide surface is rectified. Within the area surrounded by the surface, the upstream sidewall surface (ie, below the straightening surface), a circulating vortex based on the Coanda effect is formed. As a result, the flow in the suction flow path is further stabilized, so that the fluctuation of the static pressure difference between the flow in the suction flow path and the main flow is suppressed, and the main flow and the boundary layer can be separated more smoothly. ..

According to the second aspect of the present invention, the boundary layer control device further comprises a plurality of flow guides arranged at intervals in the blowing direction between the upstream guide surface and the downstream guide surface. In addition, each flow guide may be bent in the suction direction toward the downstream side in the ventilation direction.

According to this configuration, the boundary layer can be smoothly turned and rectified by the flow guide. As a result, fluctuations in the flow in the suction flow path can be suppressed. As a result, the flow in the suction flow path is further stabilized, so that the fluctuation of the static pressure difference between the flow in the suction flow path and the main flow is suppressed, and the main flow and the boundary layer can be separated more smoothly. ..

According to the third aspect of the present invention, when the dimension of the straightening surface in the blowing direction is X and the distance between the pair of adjacent flow guides in the blowing direction is Y, the X and the said. Y may satisfy the relationship shown in Eq. (1).
0.5 ≤ X / Y ≤ 5 ... (1)

According to this configuration, since the size of the straightening surface in the blowing direction can be secured sufficiently large, a more stable circulating vortex can be formed below the straightening surface. As a result, the flow in the suction flow path is further stabilized, so that the fluctuation of the static pressure difference between the flow in the suction flow path and the main flow is suppressed, and the main flow and the boundary layer can be separated more smoothly. ..

According to the fourth aspect of the present invention, the boundary layer control device further includes a downstream connection flow path provided further downstream of the connection flow path in the ventilation direction and connected to the suction flow path. May be good.

According to this configuration, since the downstream connection flow path is formed, the boundary layer newly generated on the downstream side of the upstream connection flow path can be sucked toward the suction flow path. This makes it possible to further reduce the possibility that the boundary layer is included in the flow on the downstream side in the blowing direction. Further, the suction flow rate (negative pressure) required for the connection flow path and the downstream connection flow path can be suppressed to be small. As a result, the influence of the stagnation pressure (negative pressure) generated when the boundary layer is sucked downward can be reduced. This makes it possible to distribute the mainstream more stably.

According to the fifth aspect of the present invention, the region between the connection flow path and the downstream side connection flow path on the floor surface extends in a direction away from the floor surface toward the downstream side in the ventilation direction. The inclined surface, which is an inclined surface and faces the upstream side in the blowing direction in the downstream connecting flow path, may face the inclined surface in the blowing direction.

According to this configuration, the boundary layer flowing in the region between the connection flow path on the floor surface and the downstream connection flow path is stably guided along the inclined surface, and the upstream side in the downstream connection flow path is stably guided. The boundary layer can be efficiently captured by the facing surface. As a result, the mainstream and the boundary layer can be separated more smoothly, and the mainstream can be distributed more stably.

According to the sixth aspect of the present invention, the wind tunnel test device is arranged on the downstream side of the boundary layer control device according to any one of the above and the boundary layer control device, and the moving object is installed. It is provided with a ground plate and a blower that blows wind to the test object.

According to this configuration, the influence of the boundary layer is suppressed, so that a wind tunnel test device capable of performing the test more accurately can be obtained.

According to the present invention, it is possible to provide a boundary layer control device and a wind tunnel test device capable of further reducing the influence of the boundary layer.

It is a schematic diagram which shows the structure of the wind tunnel test apparatus which concerns on 1st Embodiment of this invention. It is an enlarged view of the main part of the wind tunnel test apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the structure of the boundary layer control apparatus which concerns on 1st Embodiment of this invention. It is an enlarged sectional view of the main part of the boundary layer control apparatus which concerns on the 2nd Embodiment of this invention. It is an enlarged sectional view of the main part of the boundary layer control apparatus which concerns on 3rd Embodiment of this invention. It is sectional drawing explaining the operation of the boundary layer control apparatus which concerns on 3rd Embodiment of this invention. It is an enlarged sectional view of the main part which shows the modification of the boundary layer control apparatus which concerns on each embodiment of this invention.

[First Embodiment]
Hereinafter, the wind tunnel test apparatus 100 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 3. As shown in FIG. 1, the wind tunnel test device 100 includes a wind tunnel main body 1, an air passage 2, a fan 3, and a boundary layer control device 4.

The wind tunnel main body 1 has a measuring chamber 11 and a moving ground plate 12 arranged inside the measuring chamber 11. The moving ground plate 12 is a device for simulating a running state of an automobile M, which is a test object. As shown in FIG. 2, the moving ground plate 12 has a pair of rollers 13, a belt 14 spanned between the rollers 13, and a drive device (not shown). The belt 14 rotates in a direction opposite to the rotation direction of the wheels of the automobile M. The belt 14 rotates in synchronization with the rotation speed of the wheels. The air flow F (wind) is supplied into the measurement chamber 11 through the air passage 2.

As shown in FIG. 1 again, the air passage 2 has a tubular shape through which air flows. The air passage 2 has an air passage main body 21, an air cooling unit 22 provided in the air passage main body 21, a rectifying unit 23, and a plurality of corner vanes 24. The air passage main body 21 has an annular shape extending from an intake port 25 provided on one side of the measurement chamber 11 to an air outlet 26 provided on the other side of the measurement chamber 11 through the outside of the measurement chamber 11. .. In the following description, the direction from the blower port 26 to the intake port 25 in the measurement chamber 11 is referred to as a blower direction. Further, the side on which the intake port 25 is located when viewed from the air outlet 26 is referred to as a downstream side in the air blowing direction, and the opposite side thereof is referred to as an upstream side.

The air passage main body 21 is connected to a first pipe 21a connected to the intake port 25, a second pipe 21b connected in a direction orthogonal to the first pipe 21a in a plan view, and a direction orthogonal to the second pipe 21b. The third pipe 21c, the fourth pipe 21d extending in the direction orthogonal to the third pipe 21c, the fifth pipe 21e extending in the direction orthogonal to the fourth pipe 21d and connected to the above-mentioned air outlet 26, have. At the corner portion formed by the first pipe 21a and the second pipe 21b, a corner vane 24A for rectifying the air flow and allowing the air flow to pass through the corner portion smoothly is provided. Similarly, a corner vane 24B is provided at a corner formed by the second pipe 21b and the third pipe 21c. A corner vane 24C is provided at a corner formed by the third pipe 21c and the fourth pipe 21d. A corner vane 24D is provided at a corner formed by the fourth pipe 21d and the fifth pipe 21e.

Inside the third pipe 21c, a fan 3 for pressure-feeding the air in the air passage main body 21 is provided. The fan 3 pumps air from the second pipe 21b side toward the fourth pipe 21d side. That is, inside the air passage main body 21, air flows in the order of the first pipe 21a, the second pipe 21b, the third pipe 21c, the fourth pipe 21d, the fifth pipe 21e, and the measurement chamber 11.

Inside the fifth pipe 21e, an air cooling unit 22 and a rectifying unit 23 are provided in order from the upstream side. The air cooling unit 22 is a heat exchanger that adjusts the temperature of the air by exchanging heat between the air passing through the air cooling unit 22 and the refrigerant. The rectifying unit 23 is provided to rectify the temperature-controlled air flow through the air cooling unit 22 to create a laminar flow state.

Next, the configuration of the boundary layer control device 4 will be described with reference to FIGS. 2 and 3. As shown in FIG. 2, inside the measuring chamber 11, air (air flow F) circulates from the upstream side to the downstream side in the blowing direction. In the vicinity of the floor surface B of the measurement chamber 11, a part of the air flow F is dragged by the frictional force generated between the air flow F and the floor surface B, so that the boundary layer Fb is formed. In the following description, the components of the air flow F excluding the boundary layer Fb are referred to as mainstream Fm. That is, the air flow F includes the boundary layer Fb and the mainstream Fm in the direction away from the floor surface B. The mainstream Fm has a uniform flow velocity distribution in the height direction with respect to the floor surface B. On the other hand, the flow velocity of the boundary layer Fb is smaller than the flow velocity of the mainstream Fm, and the flow velocity becomes lower as it approaches the floor surface B, which affects the reproducibility when simulating the running state of the automobile M in the wind tunnel test. In some cases. The boundary layer control device 4 is provided to reduce the influence on the wind tunnel test by sucking the boundary layer Fb.

More specifically, the boundary layer control device 4 includes a suction flow path 41, a connection flow path 42, a rectifying surface 43 (see FIG. 3), a flow guide 44 (see FIG. 3), and a suction fan 45 (FIG. 3). 1) and. The suction flow path 41 is provided below the floor surface B of the measurement chamber 11. The suction flow path 41 extends in a direction away from the floor surface B. More specifically, the suction flow path 41 extends vertically downward from the floor surface B side. The upper end of the suction flow path 41 is connected to a connection flow path 42 described later. A suction fan 45 is connected to the lower end of the suction flow path 41. The suction fan 45 sucks the air flowing through the suction flow path 41 and the connection flow path 42. That is, in the suction flow path 41, air flows in the direction from the upper side (floor surface B side) to the lower side (suction fan 45 side). In the following description, the direction from the upper side to the lower side is referred to as a suction direction. The upstream side surface (that is, the surface facing the downstream side) of the suction flow path 41 is an upstream side wall surface 41a extending in the suction direction.

The connection flow path 42 connects the space on the floor surface B and the suction flow path 41. The end of the connection flow path 42 on the floor surface B side is an opening 41b that opens on the floor surface B. The dimension of the connecting flow path 42 in the blowing direction is set smaller than the dimension of the suction flow path 41. As shown in FIG. 3, the surface located on the upstream side of the connection flow path 42 (that is, the surface facing the downstream side) is from the upper side to the lower side in the suction direction from the upstream side to the downstream side in the ventilation direction. It is said to be an extending upstream guide surface 42a. The surface located on the downstream side of the connection flow path 42 (that is, the surface facing the upstream side) is the downstream side extending so as to curve from the upper side to the lower side in the suction direction from the upstream side to the downstream side in the ventilation direction. It is said to be a guide surface 42b. That is, the connection flow path 42 extends so as to bend in the suction direction from the upstream side to the downstream side.

A plurality of flow guides 44 are provided between the upstream guide surface 42a and the downstream guide surface 42b in the connection flow path 42. The flow guide 44 rectifies the flow of air that has flowed into the connection flow path 42 from above the floor surface B. In the present embodiment, the flow guide 44 includes a main flow guide 44 m located on the most upstream side in the blowing direction, and five sub flow guides 44s arranged at equal intervals on the downstream side of the main flow guide 44 m. Have. The upstream end of the main flow guide 44m is connected to the downstream end of the upstream guide surface 42a of the connecting flow path 42. The main flow guide 44m is curved from the upper side to the lower side in the suction direction from the upstream side to the downstream side in the ventilation direction. Of both sides of the main flow guide 44m in the thickness direction, the surface facing upward is the main guide surface 44a connected flush with the upstream guide surface 42a. Of both sides of the main flow guide 44m in the thickness direction, the surface facing downward is a rectifying surface 43 facing the upstream side wall surface 41a of the suction flow path 41 at intervals in the blowing direction. The straightening surface 43 extends so as to recede from the downstream end of the upstream guide surface 42a to the upstream side. More specifically, the straightening surface 43 extends from the end of the upstream guide surface 42a on the suction flow path 41 side so as to extend the upstream guide surface 42a toward the lower side of the floor surface B. Further, the rectifying surface 43 extends in the suction direction so as to recede from the predetermined position to the upstream side in the blowing direction. As a result, the rectifying surface 43 rectifies the air flow in the suction flow path 41.

Each sub-flow guide 44s has a flat plate portion 44f and a curved portion 44c. One end of the flat plate portion 44f is located on the opening 41b of the connection flow path 42, and extends from the upper side to the lower side in the suction direction from the upstream side to the downstream side in the ventilation direction. The curved portion 44c is connected to the lower end of the flat plate portion 44f, and is curved (bent) from the upper side to the lower side in the suction direction from the upstream side to the downstream side in the blowing direction. Further, the length of the flat plate portion 44f is set longer than that of the sub-flow guide 44s located on the upstream side in the blowing direction. That is, the height position of the lower end portion (lower end portion of the curved portion 44c) of each sub-flow guide 44s in the suction direction is lower than that of the sub-flow guide 44s located on the upstream side.

As shown in FIG. 3, the dimension of the straightening surface 43 in the blowing direction is X, and the dimension in the blowing direction between the lower end of the main flow guide 44m and the auxiliary flow guide 44s adjacent to the main flow guide 44m. When (that is, the distance between the downstream ends of the flow guides 44 adjacent to each other) is Y, it is desirable that X and Y are set so as to satisfy the relationship of the following equation (1).
0.5 ≤ X / Y ≤ 5 ... (1)
More preferably, X and Y satisfy the relationship of the following equation (2), and most preferably, X and Y satisfy the relationship of the following equation (3).
0.5 ≤ X / Y ≤ 3 ... (2)
0.5 ≤ X / Y ≤ 1.5 ... (3)

Subsequently, the operation of the wind tunnel test device 100 and the boundary layer control device 4 according to the present embodiment will be described. Prior to operating the wind tunnel test apparatus 100, an automobile M (or a transportation machine such as a two-wheeled vehicle or a railroad vehicle) as a test object is installed on a moving ground plate 12 in the measuring chamber 11. More specifically, the front end portion of the automobile M is arranged so as to face the air outlet 26. Next, the wheels of the automobile M are rotated on the moving ground plate 12. The moving ground plate 12 rotates with the rotation of the wheels. Further, by driving the fan 3, an air flow F is generated in the air passage 2. This air flow F flows into the measuring chamber 11 in a laminar flow state through the air outlet 26. In the measurement chamber 11, the air flow F collides with the automobile M from the front side. As a result, the traveling state of the automobile M is reproduced at a fixed position. The air flow F that has passed through the surface of the automobile M flows into the air passage 2 again through the intake port 25 provided on the downstream side of the measurement chamber 11.

Here, in the vicinity of the floor surface B of the measurement chamber 11, a boundary layer Fb is formed by dragging a part of the air flow F with the floor surface B by the frictional force generated. Since the flow velocity of the boundary layer Fb is smaller than the flow velocity of the mainstream Fm, it may affect the reproducibility when simulating the traveling state of the automobile M in the wind tunnel test. Therefore, the wind tunnel test device 100 according to the present embodiment includes the above-mentioned boundary layer control device 4 in order to reduce the boundary layer Fb.

As shown in FIG. 3, the boundary layer Fb generated in the vicinity of the floor surface B is sucked further downward from the floor surface B via the connection flow path 42 and the suction flow path 41 by the suction fan 45 described above. .. More specifically, the boundary layer Fb is smoothly guided along the upstream guide surface 42a and the downstream guide surface 42b of the connection flow path 42, and then is sucked below the floor surface B by the suction flow path 41. Will be done. This makes it possible to smoothly separate the mainstream Fm flowing along the floor surface B and the boundary layer Fb. Further, by smoothly separating the mainstream Fm and the boundary layer Fb, the influence of the stagnation pressure (negative pressure) generated when the boundary layer Fb is sucked downward through the suction flow path 41 can be reduced. As a result, the mainstream Fm can be distributed more stably. This makes it possible to further reduce the influence of the boundary layer Fb.

In addition, since the rectifying surface 43 by the main flow guide 44m is formed between the downstream end of the upstream guide surface 42a and the upstream side wall surface 41a of the suction flow path 41, the upstream guide surface The downward flow along the 42a forms a circulation vortex Vc based on the Coanda effect in the region A surrounded by the straightening surface 43 and the upstream side wall surface 41a (that is, below the straightening surface 43). The circulating vortex Vc constantly swirls in the region A. As a result, the possibility of other vortices being generated in other regions in the suction flow path 41 is reduced, so that the flow in the suction flow path 41 is further stabilized. As a result, the fluctuation of the static pressure difference between the flow in the suction flow path 41 and the mainstream Fm is suppressed, and the mainstream Fm and the boundary layer Fb can be separated more smoothly.

Further, according to the above configuration, the boundary layer Fb can be smoothly turned and rectified by the flow guide 44. As a result, fluctuations in the flow in the suction flow path 41 can be suppressed. As a result, the flow in the suction flow path 41 is further stabilized, so that the fluctuation of the static pressure difference between the flow in the suction flow path 41 and the mainstream Fm is suppressed, and the mainstream Fm and the boundary layer Fb are separated more smoothly. Is possible.

In addition, in the above embodiment, when the dimension of the straightening surface 43 in the blowing direction is X and the distance between the downstream ends of the adjacent flow guides 44 is Y, X and Y are the above (1). ) Satisfies the relationship shown in the equation. According to this configuration, since the dimension of the rectifying surface 43 in the blowing direction can be secured sufficiently large, a more stable circulation vortex Vc can be formed below the rectifying surface 43. As a result, the flow in the suction flow path 41 is further stabilized, so that the fluctuation of the static pressure difference between the flow in the suction flow path 41 and the mainstream Fm is suppressed, and the mainstream Fm and the boundary layer Fb are separated more smoothly. Is possible.

The first embodiment of the present invention has been described above. It should be noted that various changes and modifications can be made to the above configuration as long as the gist of the present invention is not deviated.

[Second Embodiment]
Next, the second embodiment of the present invention will be described with reference to FIG. The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. The present embodiment is different from the first embodiment in that another flow path (downstream side connection flow path 242) is further provided at a space further downstream of the connection flow path 42 in the blowing direction. ing. The lower end of the downstream connection flow path 242 is connected to the suction flow path 41 described above. The downstream connection flow path 242 sucks air in a direction away from the floor surface B. In FIG. 4, the above-mentioned flow guide 44 is not shown.

According to the above configuration, the boundary layer Fb'that could not be completely sucked by the connecting flow path 42 on the upstream side is sucked by the suction flow path 41 via the connecting flow path 242 on the downstream side. This makes it possible to further reduce the possibility that the boundary layer Fb'is included in the flow on the downstream side in the blowing direction. Further, the suction flow rate (negative pressure) required for the connection flow path 42 and the downstream connection flow path 242 can be suppressed to be small. As a result, the influence of the stagnation pressure (negative pressure) generated when the boundary layer Fb'is sucked downward can be reduced. As a result, the mainstream Fm can be distributed more stably.

The second embodiment of the present invention has been described above. It should be noted that various changes and modifications can be made to the above configuration as long as the gist of the present invention is not deviated. For example, in the second embodiment, an example in which only one downstream connection flow path 242 is provided on the downstream side of the connection flow path 42 has been described. However, the number of downstream connection flow paths 242 is not limited to one, and may be two or more. The larger the number of downstream connection flow paths 242, the more sufficiently the boundary layer Fb'can be sucked and reduced.

[Third Embodiment]
Subsequently, the third embodiment of the present invention will be described with reference to FIGS. 5 and 6. The same components as those of the above embodiments are designated by the same reference numerals, and detailed description thereof will be omitted. This embodiment differs from the first embodiment in the following points in addition to the configuration of the second embodiment. That is, in the present embodiment, the region between the connection flow path 42 and the downstream side connection flow path 242 on the floor surface B is an inclined surface S extending in a direction away from the floor surface B toward the downstream side in the ventilation direction. ing. More specifically, the inclined surface S is inclined downward toward the downstream side in the blowing direction. As a result, the surface of the downstream connection flow path 242 facing the upstream side faces the inclined surface S in the blowing direction.

According to the above configuration, the boundary layer Fb'flowing in the region between the connection flow path 42 and the downstream side connection flow path 242 on the floor surface B is stably guided along the inclined surface S and is on the downstream side. The boundary layer Fb'can be efficiently captured by the surface of the connection flow path 242 facing the upstream side (see FIG. 6). As a result, the mainstream Fm and the boundary layer Fb'can be separated more smoothly, and the mainstream Fm can be distributed more stably.

The third embodiment of the present invention has been described above. It should be noted that various changes and modifications can be made to the above configuration as long as the gist of the present invention is not deviated. For example, in the third embodiment, an example in which only one downstream connection flow path 242 is provided on the downstream side of the connection flow path 42 has been described. However, the number of downstream connection flow paths 242 is not limited to one, and may be two or more. The larger the number of downstream connection flow paths 242, the more sufficiently the boundary layer Fb'can be sucked and reduced.

Further, in each of the above embodiments, an example in which the flow guide 44 is provided in the connection flow path 42, and the lower surface of the main flow guide 44 m is the rectifying surface 43 has been described. However, the flow guide 44 does not necessarily have to be provided, and as shown in FIG. 7, the end portion on the downstream side of the upstream side guide surface 42a of the connection flow path 42 and the upstream side wall surface 41a of the suction flow path 41. It is also possible to form the rectifying surface 43 by arranging the rectifying surfaces 43 at different positions in the blowing direction. With this configuration as well, the same effects as those described above can be obtained.

In addition, in each of the above embodiments, the configuration in which the air passage 2 forms an annular flow path has been described as an example. However, the configuration of the air passage 2 is not limited to the above, and a non-annular flow path (Eiffel type) can be used as the air passage 2. Even with this type of air passage 2, the configuration according to each of the above embodiments can be suitably applied. Further, the arrangement of the air cooling unit 22, the rectifying unit 23, the plurality of corner vanes 24, etc. in the air passage 2 is not limited to the example of the above embodiment, and can be appropriately changed according to the specifications and environmental conditions. Is.

1 ... Wind tunnel body 2 ... Air passage 3 ... Fan 4 ... Boundary layer control device 11 ... Measurement room 12 ... Moving ground plate 13 ... Roller 14 ... Belt 21 ... Air passage body 22 ... Air cooling unit 23 ... Rectification unit 24 ... Corner vane 25 ... Intake port 26 ... Blower port 41 ... Suction flow path 42 ... Connection flow path 43 ... Rectifying surface 44 ... Flow guide 45 ... Suction fan 100 ... Wind tunnel test device 242 ... Downstream side connection flow path 21a ... First pipe 21b ... No. 2nd pipe 21c ... 3rd pipe 21d ... 4th pipe 21e ... 5th pipe 24a ... A corner vane 24b ... B corner vane 24c ... C corner vane 24d ... D corner vane 41a ... upstream side wall surface 41b ... opening 42a ... upstream side Guide surface 42b ... Downstream guide surface 44a ... Main guide surface 44c ... Curved portion 44f ... Flat plate portion 44m ... Main flow guide 44s ... Sub-flow guide A ... Region F ... Air flow Fb ... Boundary layer Fm ... Mainstream M ... Automobile S ... Inclined surface Vc ... Circulating vortex

Claims (6)

A boundary layer control device that sucks in the boundary layer formed by the friction between the blown air and the floor surface.
A suction flow path provided below the floor surface and having an upstream side wall surface extending along the suction direction while sucking air in the suction direction which is a direction away from the floor surface.
From the floor surface, it bends and extends in the suction direction toward the downstream side in the ventilation direction, which is the direction in which the air is blown, and is connected to the suction flow path and is located on the upstream side in the ventilation direction. A connection flow path having an upstream guide surface and a downstream guide surface located on the downstream side in the ventilation direction.
The upstream guide surface extends from the end of the upstream guide surface on the suction flow path side to a predetermined position so as to extend below the floor surface, and recedes from the predetermined position to the upstream side in the air blowing direction. A rectifying surface that rectifies the flow of air by extending in the suction direction as described above,
Boundary layer control device. A plurality of flow guides arranged at intervals in the blowing direction are further provided between the upstream guide surface and the downstream guide surface, and each flow guide is directed toward the downstream side in the blowing direction. The boundary layer control device according to claim 1, which is bent in the suction direction. When the dimension of the rectifying surface in the blowing direction is X and the distance between the pair of adjacent flow guides in the blowing direction is Y, the X and the Y have the relationship shown in the equation (1). The boundary layer control device according to claim 2.
0.5 ≤ X / Y ≤ 5 ... (1) The boundary layer control device according to any one of claims 1 to 3, further comprising a downstream connection flow path provided on the downstream side of the connection flow path in the ventilation direction and connected to the suction flow path. The region between the connecting flow path and the downstream connecting flow path on the floor surface is an inclined surface extending in a direction away from the floor surface toward the downstream side in the blowing direction.
The boundary layer control device according to claim 4, wherein the surface of the downstream connection flow path facing the upstream side in the blowing direction faces the inclined surface in the blowing direction. The boundary layer control device according to any one of claims 1 to 5.
A moving ground plate located downstream of the boundary layer control device and on which the test object is installed,
A blower that blows wind to the test object,
A wind tunnel test device equipped with.

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