JP6550255B2 - Boundary layer control device and wind tunnel test device using the same - Google Patents

Description

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

  Wind tunnel testing equipment is used to test the characteristics for air flow. The wind tunnel test apparatus is provided with a blower at one end side of the device, drives the blower to form a flow of air in the wind tunnel, and measures various characteristics in a measurement area. In the wind tunnel test apparatus, in order to test the characteristics of the running vehicle, a boundary layer control device is provided to control the characteristics of the boundary layer at the floor interface of the wind tunnel where a difference occurs between the test conditions and the actual running condition. There is.

  In Patent Document 1, when the jet air is circulated by an air blower through an annular continuous air flow path and the jet air is blown out to the measurement unit through the blowout port, the mainstream air of the jet air is generated in the boundary layer generated on the floor interface side. A wind tunnel boundary layer controller having a suction duct for sucking in and discharging in a direction perpendicular to the main flow direction of jet air is described. The wind tunnel boundary layer control device described in Patent Document 1 reduces the stagnation pressure of jet air sucked into the suction duct and reduces the obstruction of the flow of the jet air in the main flow direction.

JP, 2009-156695, A

  Here, the wind tunnel test apparatus can control the flow of gas in the boundary layer which is the floor boundary surface of the wind tunnel by using the boundary layer control apparatus as in Patent Document 1, and the reproducibility of the wind tunnel test is high. can do. Here, in addition to the test for analyzing the flow of air, the wind tunnel test apparatus may perform a test for measuring the generation state of noise. In this case, the test is performed with the boundary layer control device stopped, but sound may be generated due to the structure of the boundary layer control device. On the other hand, by blocking the suction port, it is possible to suppress the generation of noise, but since work occurs, it takes time and labor, and efficiency decreases because work time is also generated.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a boundary layer control device capable of efficiently executing various tests and a wind tunnel test device using the same.

  The present invention for solving the above-mentioned problems is a boundary layer control device connected to an air flow path and connected to a floor surface on the air flow path side of a measurement area of a measurement chamber to which air is supplied from the air flow path. A suction duct connected to the floor surface on the air passage side of the measurement area of the measurement chamber, and a suction machine connected to the suction duct and suctioning air in the measurement chamber via the suction duct; And a suction plate disposed on the entire surface of the end surface of the duct on the floor surface side and having a plurality of through holes formed therein, wherein the through holes are formed side by side in the flow direction of the air in the measurement chamber; It is characterized in that the opening area of the surface on the measurement chamber side is larger than the opening area of the surface on the suction machine side.

  Here, it is preferable that the opening area of the through hole gradually decreases from the surface on the measurement chamber side toward the surface on the suction machine side.

  Preferably, the through hole has an angle of 30 ° or more between a center line and a line connecting an opening on the surface on the measurement chamber side and an opening on the surface on the suction machine side.

  Preferably, the through hole has a chamfered portion formed at an end on the measurement chamber side.

  The present invention for solving the above-mentioned problems is a boundary layer control device connected to an air flow path and connected to a floor surface on the air flow path side of a measurement area of a measurement chamber to which air is supplied from the air flow path. A suction duct connected to the floor surface on the air passage side of the measurement area of the measurement chamber, and a suction machine connected to the suction duct and suctioning air in the measurement chamber via the suction duct; A suction plate disposed on the entire surface of the end surface of the duct on the floor surface side and having a plurality of through holes formed therein; and the through holes have a chamfered portion formed at an end portion on the measurement chamber side; The chamfered portion may be formed to have a depth of 15% or more of the width of the through hole in the air flow direction.

  Preferably, the chamfered portion is a convex surface on the center side of the through hole, and is a curved surface in which a tangent line overlaps a surface on the measurement chamber side at a connection position with the surface on the measurement chamber side.

  Moreover, it is preferable that the protrusion part which protrudes in the said suction machine side is formed in the surface by the side of the said suction machine along the said through-hole in the said suction board.

  The present invention for solving the above-mentioned problems is a boundary layer control device connected to an air flow path and connected to a floor surface on the air flow path side of a measurement area of a measurement chamber to which air is supplied from the air flow path. A suction duct connected to the floor surface on the air passage side of the measurement area of the measurement chamber, and a suction machine connected to the suction duct and suctioning air in the measurement chamber via the suction duct; And a suction plate disposed on the entire surface of the end surface of the duct on the floor surface side and having a plurality of through holes formed therein, wherein the suction plate is arranged along the penetration portion in the suction machine side surface. It is characterized in that a projecting portion which protrudes to the suction machine side is formed.

  Moreover, it is preferable that the said protrusion part has covered the perimeter of the said penetration part.

  In the through hole, the extending direction is inclined with respect to the flow direction of the air of the measuring chamber, and is inclined with respect to the extending direction of the portion of the suction duct connected to the measuring chamber. Is preferred.

  The present invention for solving the above-mentioned problems is a boundary layer control device connected to an air flow path and connected to a floor surface on the air flow path side of a measurement area of a measurement chamber to which air is supplied from the air flow path. A suction duct connected to the floor surface on the air passage side of the measurement area of the measurement chamber, and a suction machine connected to the suction duct and suctioning air in the measurement chamber via the suction duct; The suction plate is disposed on the entire surface of the end face of the floor surface side of the duct and has a plurality of through holes formed therein, and the through holes have an extending direction with respect to the air flow direction of the measurement chamber It is characterized in that it is inclined with respect to the extending direction of the portion of the suction duct connected to the measurement chamber.

  Moreover, it is preferable that the said through-hole is circular in cross section.

  Moreover, it is preferable that the said through-hole is a slit extended in the direction orthogonal to the flow direction of the air of the said measurement chamber.

  The present invention for solving the above-mentioned problems is a wind tunnel test device, characterized by having the boundary layer control device according to any of the above and a measurement chamber to which the boundary layer control device is connected. I assume.

  According to the present invention, the air can be appropriately sucked in at the time of suction by the suction plate disposed at the suction port, and the generation of noise can be suppressed at the time of stop. Thereby, various tests can be performed efficiently.

FIG. 1 is a schematic view showing a schematic configuration of a wind tunnel test apparatus. FIG. 2 is a schematic view showing a schematic configuration of the boundary layer control device. FIG. 3 is a top view showing a part of the boundary layer control device in an enlarged manner. FIG. 4 is a cross-sectional view showing a suction plate and a suction duct of the boundary layer control device. FIG. 5 is a top view showing another example of the suction plate of the boundary layer control device. FIG. 6 is a top view showing another example of the suction plate of the boundary layer control device. FIG. 7 is a cross-sectional view showing a suction plate and a suction duct of another example boundary layer control device. FIG. 8 is a cross-sectional view showing a suction plate and a suction duct of a boundary layer control device of another example. FIG. 9 is a cross-sectional view showing a suction plate and a suction duct of a boundary layer control device of another example. FIG. 10 is a perspective view showing a schematic configuration of the protrusion. FIG. 11 is a perspective view showing a schematic configuration of the protrusion. FIG. 12 is a cross-sectional view showing a suction plate and a suction duct of a boundary layer control device of another example. FIG. 13 is a cross-sectional view showing an example of another shape of the through hole.

  Hereinafter, modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. Further, constituent elements in the following embodiments include those which can be easily conceived by those skilled in the art, substantially the same ones, and so-called equivalent ranges. Furthermore, the components disclosed in the following embodiments can be combined as appropriate without departing from the scope of the present invention.

  A wind tunnel test apparatus having a boundary layer control device according to the present embodiment will be described with reference to the drawings. FIG. 1 is a schematic view showing a schematic configuration of a wind tunnel test apparatus.

  The wind tunnel test apparatus 10 includes a wind tunnel 12, a fan (blower) 13, and a boundary layer control device 14. The wind tunnel 12 is a path through which air flows, and includes a blowing passage 15 and a measurement chamber 17. A plurality of, in the present embodiment, the air passage 15 is a conduit bent at four locations, one end of which is an inlet (collector) 20 and the other end is an outlet 22. In the air flow path 15, the suction port 20 and the blowout port 22 face each other.

  Further, the wind tunnel 12 is provided with corner vanes 26a, 26b, 26c, 26d at four bent portions, that is, corner portions of the air passage 15. The corner vanes 26a, 26b, 26c, 26d are mechanisms for guiding the direction of the air flowing through the air passage 15 from the upstream side toward the downstream side. In the present embodiment, the corner vanes 26c, 26d, 26a, 26b are arranged in the order from the suction port 20 to the blowout port 22. The air flow path 15 reduces the resistance in the air flow path 15 by guiding air by the corner vanes 26 c, 26 d, 26 a, 26 b.

  The measurement chamber 17 is a chamber into which both ends of the air passage 15 are inserted. In the measurement chamber 17, the suction port 20 and the blowout port 22 are exposed to the inside. The measurement chamber 17 is provided with a test area between the suction port 20 and the air outlet 22. In this embodiment, a measurement area 27 is provided in which the vehicle 8 is disposed. Thus, in the wind tunnel 12, both ends of the air passage 15 are connected to the measurement chamber 17, and the air passage 15 and the measurement chamber 17 form a path through which air circulates.

  The fan (fan) 13 is disposed inside the air passage 15. Specifically, it is disposed between the corner vanes 26d and the corner vanes 26a. The fan 13 sends air from the corner vanes 26d to the corner vanes 26a, and the corner vanes 26a, the corner vanes 26b, the air outlet 22, the measuring chamber 17, the inlet 20, the corner vanes 26c, and the corner vanes 26d in this order. The jet air 30 which is a flow of air circulating in the air passage 15 and the measurement chamber 17 is formed.

  The wind tunnel test apparatus 10 further includes an air cooling device between the air outlet 22 and the corner vanes 26 b, that is, downstream of the fan 13 and upstream of the air outlet 22 in the flow direction of the jet air 30. A heat exchanger 28 and a rectifying unit 29 are provided. The rectifying unit 29 is disposed downstream of the air cooling device 28. The air cooling device 28 regulates the temperature of the jet air 30 supplied to the measurement chamber 17. The straightening unit 29 includes, for example, a straightening wire mesh and a straightening grid, and straightens the flowing jet air 30. By rectifying with the rectifying unit 29, the jet air 30 supplied from the outlet 22 to the measurement chamber 17 can be rectified.

  The wind tunnel test apparatus 10 drives a fan (blower) 13 to form an air flow in the wind tunnel 12. Specifically, the air in the measurement chamber 17 is collected from the suction port 20 by forming a flow of jet air 30 flowing in one direction in the air flow path 15 by the fan 13, and is allowed to pass through the air flow path 15, After rectified by the rectifying unit 29, the jet air 30 can be blown out from the blowout port 22 to the measurement chamber 17. Thus, the jet air 30 can be blown to the vehicle 8 in the measurement area 27. The wind tunnel test apparatus 10 can adjust the wind speed of the jet air 30 blown to the measurement area 27 by the fan 13.

  The wind tunnel test apparatus 10 installs the vehicle 8 in the measurement area 27 of the measurement chamber 17, further installs the measurement device, and measures various measurement parameters in a state where the jet air 30 is blown to the vehicle 8 And various tests such as noise can be conducted.

  In the wind tunnel test apparatus 10, the control of the wind speed may be performed by restricting the fan suction flow rate by the inlet guide vane, restricting the fan discharge flow rate by the damper, controlling the flow rate by the variable pitch of the fan 13, or the like.

  Next, the boundary layer control device 14 will be described using FIGS. 2 to 4 in addition to FIG. FIG. 2 is a schematic view showing a schematic configuration of the boundary layer control device. FIG. 3 is a top view showing a part of the boundary layer control device in an enlarged manner. FIG. 4 is a cross-sectional view showing a suction plate and a suction duct of the boundary layer control device. In addition, in order to show the shape of a through-hole intelligibly, FIG. 4 is making the through-hole large and schematically.

  The boundary layer control device 14 controls the floor of the measurement chamber 17 between the outlet 22 and the measurement area 27 in the flow direction 42 of the jet air 30 in the measurement chamber 17, that is, in the direction from the outlet 22 to the inlet 20. It is connected to the surface 40. The floor layer suction port 38 is formed at a position where the boundary layer control device 14 is connected to the floor surface 40, and the air in the measurement chamber 17 can be sucked. The boundary layer control device 14 has a suction duct 32, a pump (suction machine) 34, and a suction plate 36.

  The suction duct 32 is connected to a floor suction port 38 which is an opening formed in the floor surface 40. In the suction duct 32, a portion including a connection with the floor suction port 38 extends in a direction orthogonal to the flow direction 42. That is, the suction duct 32 is connected to the floor surface 40 at a right angle. The pump 34 sucks the air of the suction duct 32 and forms a flow in the flow direction 44, ie a flow of air from the floor suction 38 to the other end of the suction duct 32.

  The suction plate 36 is provided at the connection between the suction duct 32 and the measurement chamber 17, that is, at the floor suction port 38. The suction plate 36 is provided on the entire surface of the floor suction port 38 and blocks the floor suction port 38. The suction plate 36 may be a single plate or a plurality of plates arranged in parallel. As shown in FIG. 3, the suction plate 36 is formed with a plurality of through holes 60. The through hole 60 opens at the measurement chamber side surface 62 whose one end is exposed to the measurement chamber 17 of the suction plate 36 and opens at the pump side surface 64 whose other end is exposed to the suction duct 32. doing. That is, the through hole 60 connects the measurement chamber 17 and the suction duct 32. The through holes 60 are holes whose cross sections are circular, and are two-dimensionally arranged in a zigzag pattern. That is, a plurality of through holes 60 are formed side by side in the flow direction 42 and a plurality of the suction plates 36 are formed side by side in the direction orthogonal to the flow direction 42.

  In the through hole 60 of the present embodiment, the opening area of the opening of the measurement chamber side surface 62 is the same as that of the pump side surface 64 in the plane including the cross section along the flow direction 42, the flow direction 42 and the direction orthogonal to the floor surface 40. The shape is larger than the opening area of the opening. In the through hole 60, the cross section 66 which is the surface of the opening is a straight line. In the through hole 60 of the present embodiment, the shape of the opening in the cross section is trapezoidal.

  Here, in the wind tunnel test apparatus 10, resistance occurs between the main flow layer 50 and the floor surface 40 of the measurement chamber 17 in addition to the main flow layer 50 due to the main flow air (steady flow rate). Due to this, a boundary layer 52 with a delayed wind velocity is generated along the floor surface 60. Therefore, when the wind speed distribution of the vehicle 8 is tested, the boundary layer 52 is affected. The boundary layer 52 is a layer in the range where the velocity changes rapidly from the floor surface to the flow velocity of the mainstream air in the flow of the mainstream air near the floor surface, for example, 100% of the flow velocity of the mainstream air When the flow rate is reduced to 99% or less.

  On the other hand, the boundary layer control device 14 drives the pump 34 and sucks the air of the measurement chamber 17 from the floor surface suction port 38 through the suction duct 32 so that the air is spouted from the blowout port 22 and the flow direction Reducing the influence of the boundary layer 23 by sucking a part of the boundary layer 52 portion of the jet air 30 flowing into the flow direction 42 in the flow direction 44 perpendicular to the flow direction 42 as shown in the flow direction 46 it can. In addition, the boundary layer control device 14 causes the through hole 60 to have a shape such that the opening area of the opening of the measurement chamber side surface 62 is larger than the opening area of the opening of the pump side surface 64. Can be an asymptotically compressed flow, and air can easily enter the suction duct 32 from the measurement chamber 17.

  Next, the wind tunnel test apparatus 10 stops the pump 34 of the boundary layer control apparatus 14 when performing a test for measuring noise and the like. In this case, the jet air 30 flows in the flow direction 42 and no flow in the flow direction 44 occurs. In addition, the boundary layer control device 14 makes the through hole 60 have a shape in which the opening area of the opening of the measurement chamber side surface 62 is larger than the opening area of the opening of the pump side surface 64, thereby showing the suction duct shown in the flow direction 48. When air passes from the through hole 60 toward the measurement chamber 17 from 32, the flow becomes a rapidly expanding flow, and the air is less likely to flow. As a result, when the pump 34 is stopped, it is possible to suppress the formation of the air flow that is drawn into the flow of the jet air 30 in the flow direction 42 and the air in the suction duct 32 flows into the measurement chamber 17 .

  As described above, since the boundary layer control device 14 can make the pressure loss when flowing in the flow direction 46 smaller than the pressure loss when flowing in the flow direction 48, the flow resistance during operation of the pump 34 is increased. It is possible to reduce the flow velocity in the flow direction 48 when the pump 34 is stopped. Here, since the pressure difference between the inside of the measurement chamber 17 and the suction duct 32 is the same, it is possible to reduce the flow velocity by setting the flow rapidly and using a large pressure loss.

  The through hole 60 has a cross section 66 serving as the surface of the opening in a cross section along the flow direction 42, that is, a plane including the flow direction 42 and a direction orthogonal to the floor surface 40, and an axial direction (extension direction of the through hole 60 It is preferable that an angle θ formed with the line connecting the middle points of the horizontal surface be 30 ° or more. That is, it is preferable that an angle θa formed by the intersection of the cross section 66 and the extension of the cross section 66 be 60 ° or more. By setting the angle θ of the through holes 60 to 30 ° or more, the asymptotic compression flow and the rapidly expanding flow can be suitably formed.

  The through hole 60 has a cross-section along the flow direction 42, that is, a plane including the flow direction 42 and a direction orthogonal to the floor surface 40, the length of the through hole 60 (the middle point of the horizontal plane of the through hole Assuming that the length of the line is t and the distance of the opening on the pump side surface 64 is d, it is preferable that (t / d) ≦ 0.5. As a result, the asymptotic compression flow and the rapidly expanding flow can be suitably formed.

  In addition, the suction plate 36 has an aperture ratio, that is, the total area of the through holes 60 on the measurement chamber side surface 62 with respect to the area of the measurement chamber side surface 62 including the through holes 60 is 20% to 30%. Is preferred. Thereby, it is possible to allow an appropriate amount of air to flow into the through holes 60 of the suction plate 36, and also to suppress an increase in pressure loss.

  Here, in the suction plate 36, the through hole 60 has a shape in which the cross section of the horizontal surface is a circle, but is not limited thereto. The through hole 60 may have a shape in which the cross section of the horizontal surface is elliptical.

  FIG. 5 is a top view showing another example of the suction plate of the boundary layer control device. In the suction plate 36 a shown in FIG. 5, a plurality of through holes 60 a are formed along the flow direction 42. The through holes 60 a are elongated holes extending in a direction orthogonal to the flow direction 42, so-called slits. The suction plate 36a can also obtain the same effect by forming the through holes 60a to be slits in the flow direction 42, and by making the through holes 60a in the same shape in the cross section of the flow direction 42.

  FIG. 6 is a top view showing another example of the suction plate of the boundary layer control device. The suction plate 36b is formed with a plurality of through holes 60b. The through holes 60 b are holes whose cross section is rectangular, and are two-dimensionally arranged in a lattice. That is, a plurality of through holes 60 b are formed side by side in the flow direction 42, and the suction plates 36 are formed side by side in the direction orthogonal to the flow direction 42. As described above, even when the cross section of the through hole 60b is rectangular, the same effect can be obtained by making the cross section in the flow direction 42 the same shape. The through hole may be a polygon other than a rectangle.

  Next, another example of the boundary layer control device, specifically, another example of the through hole will be described with reference to FIGS. 7 to 13. In the boundary layer controller, the pressure loss when flowing in the flow direction 46 is smaller than the pressure loss when flowing in the flow direction 48, and the flow in the flow direction 46 and the flow in the flow direction 48 are irreversible flows. The shape of can be used. In addition, the boundary layer control device may have a plurality of shapes including one or more features of the through holes described above and below. That is, the through hole can also be made into the shape which combined the some example.

  FIG. 7 is a cross-sectional view showing a suction plate and a suction duct of another example boundary layer control device. The boundary layer controller 114 shown in FIG. 7 has a suction plate 136. The structure other than the suction plate 136 of the boundary layer control device 114 is the same as that of the boundary layer control device 14, and thus the description thereof is omitted. The suction plate 136 is formed with a through hole 160 penetrating the measurement chamber side surface 162 and the pump side surface 164. In the through hole 160, the chamfered portion 180 is formed on the measurement chamber side surface 162 in a cross section along the flow direction 42, that is, a plane including the flow direction 42 and the direction orthogonal to the floor surface 40. It is a hole where the width d of the part is constant. The chamfered portion 180 is convex toward the center of the through hole 160 and has a radius of curvature of R. The chamfered portion 180 is smoothly connected to the surface of the measurement chamber side surface 162. That is, in the chamfered portion 180, the end on the measurement chamber side surface 162 side becomes a point parallel to the measurement chamber side surface 162, and the tangent line overlaps.

  The boundary layer control device 114 provides the chamfered portion 180 on the measurement chamber side surface 162 side of the through hole 160 so that the opening area of the opening of the measurement chamber side surface 162 is the same as the opening area of the pump side surface 164. The shape can be made larger than the opening area, and the flow when passing through the through hole 160 can be an asymptotic compression flow. Further, the boundary layer control device 114 provides the chamfered portion 180 on the measurement chamber side surface 162 side of the through hole 160 so that the jet air flow 30 flowing in the flow direction 42 when the pump 34 is stopped is the measurement chamber of the through hole 160 Also when passing along the side surface 162 side, occurrence of flow separation to the flow 150 in the vicinity of the side surface of the through hole 160 can be suppressed. Thereby, the static pressure drop of the local flow around the through hole 160 can be suppressed, and the pressure difference between the measurement chamber side surface 162 of the suction plate 136 and the pump side surface 164 becomes large. It can be suppressed. Thus, the generation of the flow of air from the measurement chamber side surface 162 toward the pump side surface 164 can be suppressed. Furthermore, the separation of the flow of the jet air 30 in the flow direction 42 can be suppressed, so that the noise due to the separation can be suppressed.

  Here, in the chamfered portion 180, the relationship between the radius of curvature R and the width d preferably satisfies Rd0.15d. Thereby, the separation of the flow 150 along the measurement chamber side surface 162 can be further suppressed.

  Here, in the above embodiment, the chamfered portion 180 is a curved surface, and the shape of the through hole 160 on the measurement chamber 17 side has a bell mouth shape in which the amount of change in width decreases as it goes to the pump 34 side. It is not limited to. Here, by setting the through hole 160 in the shape of the chamfered portion 180, the separation of the flow 150 can be more suitably suppressed, and the resistance of the air flow toward the pump 34 can be further reduced. . The chamfered portion 180 may have an R shape as an ellipse. Also, a circle and a straight line may be combined.

  FIG. 8 is a cross-sectional view showing a suction plate and a suction duct of a boundary layer control device of another example. The boundary layer control device 114a shown in FIG. 8 has a suction plate 136a. The structure other than the suction plate 136a of the boundary layer control device 114a is the same as that of the boundary layer control devices 14 and 114, and thus the description thereof is omitted. The suction plate 136a is formed with a through hole 160a penetrating the measurement chamber side surface 162 and the pump side surface 164. In the through hole 160a, the chamfered portion 180a is formed on the measurement chamber side surface 162 in a cross section along the flow direction 42, that is, a plane including the flow direction 42 and the direction orthogonal to the floor surface 40. It is a hole where the width d of the part is constant. The chamfered portion 180 a is an inclined surface that is inclined 45 ° with respect to the measurement chamber side surface 162.

  As described above, by providing the chamfered portion 180a on the measurement chamber side surface 162 side of the through hole 160a, the effect of suppressing peeling is reduced more than that of the chamfered portion 180 having the R shape, but peeling can be suppressed.

  Here, in the chamfered portion 180a, it is preferable that the relationship between the distance da in the depth direction of the through hole 160a and the width d satisfy da 0.15 0.15 d. Thereby, the separation of the flow 150 along the measurement chamber side surface 162 can be further suppressed.

  FIG. 9 is a cross-sectional view showing a suction plate and a suction duct of a boundary layer control device of another example. FIG. 10 is a perspective view showing a schematic configuration of the protrusion. The boundary layer controller 214 shown in FIG. 9 has a suction plate 236. The structure of the boundary layer control device 214 other than the suction plate 236 is the same as that of the boundary layer control device 14, and thus the description thereof is omitted. The suction plate 236 is formed with a through hole 260 penetrating the measurement chamber side surface 262 and the pump side surface 264. The through hole 260 is a hole whose width D is constant in a cross section along the flow direction 42, that is, in a plane including the flow direction 42 and the direction orthogonal to the floor surface 40. The suction plate 236 has a protrusion 280 formed on the pump side surface 264. The protrusion 280 is a cylinder that covers the periphery of the opening of the through hole 260. The protrusion 280 may be fixed by being inserted into the through hole 260 or by welding the suction plate 236.

  The boundary layer control device 214 provides the projection 280 so that the resistance to pressure (pressure loss) from the measurement chamber side surface 262 to the pump side surface 264 is not increased. The resistance to flow towards 262 can be increased. Specifically, as shown in FIGS. 9 and 10, the flow 250 flowing into the portion connected to the through hole 260 inside the protrusion 280 flows into the through hole 260 as it is. On the other hand, the air flowing toward the portion other than the through hole 260 of the pump side surface 264, as shown in the flow 252, flows into between the protrusions 280 and then bounces back to the pump side surface 264 side and returns Then, it flows into the protrusion 280. As a result, the projecting portion 280 resists the flow from the pump side surface 264 toward the measurement chamber side surface 262, and air does not easily flow from the pump side surface 264 toward the measurement chamber side surface 262. As a result, it is possible to form a desired air flow both when the pump 34 is driven and when it is stopped.

  Here, in the boundary layer control device 214, when the width of the through hole 260 in the axial direction of the through hole 260 is d, and the length L of the projecting portion 280, the relationship between the width d and the length L is L / d ≧ Meet 0.1. Thereby, the function as a resistance can be reliably generated in the protrusion 280.

  FIG. 11 is a perspective view showing a schematic configuration of the protrusion. In the above embodiment, since the desired air flow can be formed when the pump 34 is driven and stopped, the protrusion 280 covers the entire circumference of the through hole 260, but the present invention is not limited to this. . The suction plate 236 a of the boundary layer control device 214 a shown in FIG. 11 has a protrusion 280 a divided into two plate portions 282. The plate portion 282 is disposed to surround the through hole 260. A gap is formed between the plate portion 282 and the plate portion 282. That is, the protrusion 280 a is formed with a notch, and there is a portion that does not surround the through hole 260. Thus, although the gap is formed, the function as the resistance of the flow of air from the pump side surface 264 to the measurement chamber side surface 262 is reduced, but from the pump side surface 264 as compared with the case where the projection is not provided. Air can be made less likely to flow toward the measurement chamber side surface 262. Preferably, the protrusion is provided in a region of 50% or more of the outer edge of the through hole 260. Thus, the function as a resistor can be reliably generated.

FIG. 12 is a cross-sectional view showing a suction plate and a suction duct of a boundary layer control device of another example. The boundary layer controller 314 shown in FIG. 12 has a suction plate 338. The structure other than the suction plate 336 of the boundary layer control device 314 is the same as that of the boundary layer control device 14, and thus the description thereof is omitted. The suction plate 336 has a through hole 360 formed in the measurement chamber side surface 362 and the pump side surface 364. The through hole 360 is a hole having a constant width in a cross section along the flow direction 42, that is, in a plane including the flow direction 42 and the direction orthogonal to the floor surface 40. The through hole 360 has a flow direction 42 in the direction from the measurement chamber side surface 362 to the pump side surface 364 with respect to the direction in which the center line is orthogonal to the flow direction 42 and the wall surface on the floor surface suction port 38 side of the suction duct 32. It is inclined in the direction to move downstream. Through holes 360, the angle theta ₁ is inclined with respect to the direction 42 center line flows, and are angle theta ₂ inclined with respect to the floor suction opening 38 side of the wall surface of the suction centerline duct 32. Angle θ1 and the angle theta ₂ is larger than 0 ° angle. Further, the flow direction 42 and the wall surface on the floor surface suction port 38 side of the duct 32 are perpendicular to each other.

  The boundary layer control device 314 is directed from the measurement chamber side surface 362 to the pump side surface 364 with respect to the wall surface on the floor surface suction port 38 side of the suction duct 32 in the direction perpendicular to the flow direction 42 Therefore, by inclining in the moving direction to the downstream side of the flow direction 42, the angle between the flow 346 from the measurement chamber side surface 362 to the pump side surface 364 and the flow direction 42 is less than 90 °. Thereby, the resistance which arises when jet air 30 flows into penetration hole 360 can be made small. Also, the boundary layer control device 314 is configured such that the measurement chamber side surface 362 to the pump side surface 364 with respect to the wall surface on the floor surface suction port 38 side of the suction duct 32 in the direction perpendicular to the flow direction 42 The flow 348 from the pump side surface 364 to the measurement chamber side surface 362 flows from the suction duct 32 into the through hole 360 by being inclined in the moving direction to the downstream side of the flow direction 42 as it goes toward Since the direction changes by θ, this becomes resistance at the time of inflow. Further, when jetted from the through hole 360 into the measurement chamber 17, the direction in the direction parallel to the flow direction 42 is reversed. This causes a collision between the flow jetted out of the through hole 360 and the flow of the jet air 30, and a stagnation pressure is generated, and the pressure loss of the flow can be increased. Air can not flow easily. It is possible to decelerate the flow velocity in the flow direction 48 when the pump 34 is stopped without increasing the flow resistance when the pump 34 is operating.

  FIG. 13 is a cross-sectional view showing an example of another shape of the through hole. The through hole 360a of the suction plate 336a of the boundary layer control device 314a shown in FIG. 13 is the surface on the measurement chamber side with respect to the wall surface on the floor surface suction port 38 side of the suction duct 32 in the direction perpendicular to the flow direction It is inclined in the direction of moving downstream in the flow direction 42 from 362 toward the pump side surface 364. The through hole 360 a has a shape in which the first hole 380 and the second hole 382 are connected. The first hole 380 and the second hole 382 have different angles with respect to the wall surface on the floor surface suction port 38 side of the suction duct 32 in the direction in which the center lines are orthogonal to the flow direction 42. The first hole 380 makes an angle with the flow direction 42 smaller than that of the second hole 382.

  The boundary layer control device 314a can further increase the resistance of the flow from the pump side surface 364 to the measurement chamber side surface 362 when the pump 34 is stopped by providing the bending portion also in the through hole 360a. It is possible to reduce the flow velocity of In addition, the boundary layer control device 314a can suction air from the measurement chamber side surface 362 to the pump side surface 364 by operating the pump 34 even when the bending portion is provided also in the through hole 360a. And the boundary layer can be suitably controlled.

8 Vehicle 10 Wind tunnel test device 12 Wind tunnel 13 Fan 14 Boundary layer control device 15 Air flow path 17 Measurement room 20 Suction port 22 Air outlet 26a, 26b, 26c, 26d Corner vane 27 Measurement area 28 Air cooling device 29 Rectifying part 30 Jet air 32 Suction duct 34 pump (suction machine)
36 suction plate 38 floor suction port 40 floor 50 main flow layer 52 boundary layer 60 through hole 62 measurement chamber side surface 64 pump side surface

Claims (12)

A boundary layer control device connected to an air flow path and connected to a floor surface on the air flow path side of a measurement area of a measurement chamber to which air is supplied from the air flow path,
A suction duct connected to the floor surface on the air passage side of the measurement area of the measurement chamber;
A suction device connected to the suction duct and suctioning air in the measurement chamber via the suction duct;
And a suction plate disposed on the entire surface of the end face on the floor surface side of the suction duct and having a plurality of through holes formed therein;
The boundary layer control device according to claim 1, wherein the suction plate is formed with a protruding portion protruding toward the suction device along the penetrating portion on a surface on the suction device side. The through bore is formed in line in the flow direction of the measuring chamber of the air, the opening area of the measuring chamber side of the surface, according to claim 1, wherein greater than the opening area of the surface of the suction-side Boundary layer control device described in . The boundary layer control device according to claim 2 , wherein the opening area of the through hole gradually decreases from the surface on the measurement chamber side toward the surface on the suction machine side. 3. The apparatus according to claim 2 , wherein an angle formed by a line connecting the opening of the surface on the measurement chamber side and the opening of the surface on the suction machine side with the center line is 30 ° or more. boundary layer control apparatus according to 3.   The boundary layer control device according to any one of claims 1 to 3, wherein the through hole has a chamfered portion formed at an end portion on the measurement chamber side. 6. The boundary layer control device according to claim 5, wherein the chamfered portion is formed at a depth of 15% or more of the width of the through hole in the air flow direction. The chamfered portion is convex toward the center of the through-hole, in the connection position between the measuring chamber side of the surface, according to claim, wherein the surface and the tangent of the measuring chamber side is a curved surface that overlaps 5 Or the boundary layer control device according to 6 . The boundary layer control device according to any one of claims 1 to 7, wherein the protrusion covers the entire circumference of the through hole. The through hole has an extending direction inclined with respect to the air flow direction of the measuring chamber, and is inclined with respect to the extending direction of a portion of the suction duct connected to the measuring chamber The boundary layer control device according to any one of claims 1 to 8 , characterized in that: The boundary layer control device according to any one of claims 1 to 9 , wherein the through hole has a circular cross section. The boundary layer control device according to any one of claims 1 to 9 , wherein the through hole is a slit extending in a direction orthogonal to the flow direction of the air in the measurement chamber. The boundary layer control device according to any one of claims 1 to 11 ,
And a measurement chamber to which the boundary layer control device is connected.

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