A three-directional adjustable device for a bridge segment model of a piv wind tunnel test

Abstract

The application discloses a three-direction adjustable device for a bridge section model in a piv wind tunnel test, and belongs to the technical field of bridge wind tunnel tests. The left fixed long rod and the right fixed long rod are used to fix the two sides of the bridge section. The fixing mode can be screw fixing. The long rod can avoid shielding the observation direction of the end of the bridge section when the bridge section is fixed. The rotating shafts of the vertical installation frame, the horizontal rotating shaft and the left fixed long rod are staggered to form a swing point. A high-speed camera arranged on the fixed shaft always rotates around the swing point with the bridge section, so that the high-speed camera always faces the fixed direction of the bridge section during the movement of the bridge section, the particle trajectory emitted by the laser can be directionally photographed, and the test data can be ensured to be comprehensive and accurate. The experimental device is not shielded in the whole piv test, and can control the rotation of the bridge section around the three XYZ axes in the wind tunnel test at any time, so that the wind direction trajectory of different wind directions on the bridge section can be simulated.

Description

Technical Field

[0001] This invention belongs to the field of bridge wind tunnel testing technology, specifically relating to a three-dimensional adjustable device for a bridge segment model in a PIV wind tunnel test. Background Technology

[0002] Due to the application of new materials and technologies in bridge engineering and the development of bridge aesthetics, bridge structures are evolving towards longer spans and lighter, more flexible designs. This makes structures more sensitive to wind effects, necessitating consideration of wind influences in bridge design. Wind tunnel testing is a crucial step in verifying the wind resistance of bridge structures. Pivot airflow (PIV) technology can visualize the flow field around the bridge and is often used in conjunction with wind tunnel testing. However, the flow field data obtained from PIV is not complete or reliable due to obstructions from ordinary supports. Furthermore, ordinary supports cannot adjust the angle and position of bridge segments in real time during wind tunnel testing. To more accurately describe the flow field information, it is necessary to invent a more reliable PIV wind tunnel testing device. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a three-way adjustable device for a bridge segment model in a PIV wind tunnel test, which can ensure the uniformity of the shooting angle of the high-speed camera while adjusting the position of the bridge segment in real time.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] This invention includes a wind tunnel test chamber, which houses a laser, a fixed-rotation section, a swing section, and a camera. The fixed-rotation section includes a vertically mounted column, on which a vertical rotating frame is coaxially rotatable. A horizontal rotating shaft is rotatable within the vertical rotating frame, and a left fixed long rod for fixing the end of a bridge segment is rotatably mounted at the end of the horizontal rotating shaft. The left fixed long rod, the horizontal rotating shaft, and the rotating shaft of the vertical rotating frame are perpendicular to each other and intersect at a point. The swing section includes an outer frame, within which an inner frame slidably rotates about the rotation axis of the vertical rotating frame. An inner seat that slidably rotates around the horizontal axis of rotation is provided within the inner frame. A fixed shaft is rotatably provided within the inner seat. A right fixed long rod for fixing the other end of the bridge segment is fixed to the end of the fixed shaft. The rotation axis of the right fixed long rod coincides with the rotation axis of the left fixed long rod. The imaging unit includes a high-speed camera, which is fixed to the fixed shaft and faces the fixed bridge segment. The laser faces the bridge segment. This structure can ensure a uniform shooting angle of the high-speed camera while adjusting the position of the bridge segment in real time.

[0006] Furthermore, the shooting unit also includes a frame, which is rotatably mounted on the fixed shaft. The axis of rotation of the frame coincides with the axis of the fixed shaft. Rotating rods are fixed at both ends of the high-speed camera. Vertical grooves are opened on both sides of the frame, and the two rotating rods are slidably mounted in the vertical grooves. Fixed cylinders are threaded onto the rotating rods, and locking screws are threaded onto the frame. The locking screws pass through the frame and abut against the side of the fixed cylinder.

[0007] Furthermore, arc-shaped rail grooves are respectively opened on the inner sides of the upper and lower edges of the outer frame, and two sliding columns are respectively fixed at the upper and lower ends of the inner frame. The ends of the sliding columns are respectively slidably placed in the arc-shaped rail grooves. First electric cylinders are respectively fixed on the left and right edges of the outer frame. The ends of the first electric cylinders are provided with rollers, and the rollers abut against the left and right outer sides of the inner frame.

[0008] Furthermore, vertical first sliding grooves are respectively opened on the left and right inner sides of the inner frame, and a support seat is vertically slidably mounted on the first sliding groove. The support seat has a groove opening downward, and a horizontal second sliding groove is opened on both sides of the groove. A cylindrical shaft is fixed at both ends of the inner seat, and the cylindrical shaft is slidably mounted in the second sliding groove. A second electric cylinder is fixed at the bottom inner side of the inner frame, and the second electric cylinder drives the support seat to move up and down.

[0009] Furthermore, a turbine is fixed to the end of the fixed shaft, and the turbine is rotatably disposed inside the inner seat. A worm gear, meshing with the turbine, is also rotatably disposed inside the inner seat. A motor is fixed on the inner seat, and the motor drives the worm gear to rotate.

[0010] The beneficial effects of this invention are as follows:

[0011] This invention uses left and right fixed long rods to fix both sides of the bridge segment. The fixing method can be screw fixing. The long rods prevent obstruction of the viewing direction at the end of the bridge segment when fixing it. Figure 2In the fixed-rotation section, the vertical frame, the horizontal rotation axis, and the rotation axis of the left fixed rod intersect to form a swing point. The bridge segment can rotate around the X-axis in the fixed-rotation section via the rotation of the vertical frame on the column, around the Y-axis in the fixed-rotation section via the rotation of the horizontal rotation axis within the vertical frame, and around the Z-axis in the fixed-rotation section via the rotation of the left fixed rod on the horizontal rotation axis. The arc-shaped movement of the inner frame on the outer frame drives the bridge segment to rotate around the Y-axis, and the arc-shaped movement of the inner seat on the inner frame drives the bridge segment to rotate around the X-axis. The fixed axis in the inner seat... The rotation of the bridge segment drives the bridge segment to rotate around the Z-axis; the high-speed camera set on the fixed axis always rotates around the swing point with the bridge segment, so that the high-speed camera always faces the fixed direction of the bridge segment during the movement of the bridge segment, and can directionally capture the trajectory of the particles emitted by the laser, which can ensure the comprehensiveness and accuracy of the experimental data; this experimental device is unobstructed throughout the PIV experiment, and can control the rotation of the bridge segment around the three axes of XYZ at any time in the wind tunnel test to simulate the wind trajectory of the bridge segment under different wind directions.

[0012] Other advantages, objectives, and features of the invention will be set forth in the following description and will be apparent to those skilled in the art in some respects, or may be learned by practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0013] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the following figures are provided for illustration:

[0014] Figure 1 This is an overall schematic diagram of the adjusting device according to an embodiment of the present invention;

[0015] Figure 2 This is a schematic diagram of the internal structure of the wind tunnel test chamber according to an embodiment of the present invention;

[0016] Figure 3 This is a schematic diagram of the structure of the rotating part according to an embodiment of the present invention;

[0017] Figure 4 This is a schematic diagram of the imaging unit according to an embodiment of the present invention;

[0018] Figure 5 This is a schematic diagram of the structure of the swinging part according to an embodiment of the present invention;

[0019] Figure 6 for Figure 5 Enlarged view of point A;

[0020] Figure 7 This is a schematic diagram of the internal structure of the inner frame in an embodiment of the present invention;

[0021] Figure 8This is a schematic diagram of the internal structure of the inner seat in an embodiment of the present invention;

[0022] The following are the markings in the attached diagram: 1. Wind tunnel test chamber; 2. Laser; 3. Fixed rotating part; 31. Column; 32. Vertical rotating frame; 33. Horizontal rotating shaft; 34. Left fixed long rod; 4. Swinging part; 41. Outer frame; 411. Arc-shaped rail groove; 412. First electric cylinder; 413. Roller; 42. Inner frame; 421. Sliding column; 422. First sliding groove; 423. Support seat; 4231. Groove; 4232. Second sliding groove; 424. Second electric cylinder; 43. Inner seat; 431. Cylinder shaft; 432. Turbine; 433. Worm gear; 434. Motor; 44. Fixed shaft; 45. Right fixed long rod; 5. Imaging part; 51. High-speed camera; 52. Seat frame; 521. Vertical groove; 53. Rotating rod; 54. Fixed cylinder; 55. Tightening screw; 6. Bridge segment. Detailed Implementation

[0023] like Figures 1-8 As shown, this invention discloses a three-dimensional adjustable device for a bridge segment model in a PIV wind tunnel test, including a wind tunnel test chamber 1, which is a rectangular hollow chamber. A high-speed fan is provided at one end of the wind tunnel test chamber to provide airflow support for the test. The wind tunnel test chamber 1 is equipped with a laser 2, a stationary / rotating unit 3, a swinging unit 4, and a camera unit 5, as shown. Figure 2 and Figure 3 As shown, the fixed-rotation part 3 includes a vertically arranged column 31. The upper and lower ends of the column 31 can be fixed to the upper and lower walls of the wind tunnel test chamber 1 and are fixed by support rods. A vertical rotating frame 32 is coaxially rotatably mounted on the column 31. A horizontal rotating shaft 33 is rotatably mounted inside the vertical rotating frame 32. A left fixed long rod 34 for fixing the end of the bridge segment 6 is rotatably mounted at the end of the horizontal rotating shaft 33. The rotating shafts of the left fixed long rod 34, the horizontal rotating shaft 33, and the vertical rotating frame 32 are perpendicular to each other and intersect at a point. Figure 5 and Figure 6 As shown, the swinging part 4 includes an outer frame 41, within which an inner frame 42 is slidably disposed, rotating around the axis of rotation of the vertical rotating frame 32. Arc-shaped rail grooves 411 are respectively formed on the inner sides of the upper and lower edges of the outer frame 41. Two sliding pillars 421 are fixed to the upper and lower ends of the inner frame 42, with the ends of the sliding pillars 421 sliding within the arc-shaped rail grooves 411. First electric cylinders 412 are fixed to the left and right edges of the outer frame 41, with rollers 413 at their ends. The rollers 413 abut against the left and right outer sides of the inner frame 42. With the push of the first electric cylinders 412, the inner frame 42 can be driven to move along the arc-shaped rail grooves 411. (Reference) Figure 7An inner seat 43, which rotates around the horizontal axis 33, is slidably disposed within the inner frame 42. Vertical first sliding grooves 422 are respectively opened on the left and right inner sides of the inner frame 42. Support seats 423 are vertically slidably disposed on the first sliding grooves 422. The support seats 423 have downwardly opening grooves 4231. Horizontal second sliding grooves 4232 are opened on both sides of the grooves 4231. Cylindrical shafts 431 are fixed to both ends of the inner seat 43 and are slidably disposed within the second sliding grooves 4232. A second electric cylinder 424 is fixed to the bottom inner side of the inner frame 42, and the second electric cylinder 424 drives the support seat 423 to move up and down. (Reference) Figure 8 The inner seat 43 is rotatably provided with a fixed shaft 44, and a turbine 432 is fixed to the end of the fixed shaft 44. The turbine 432 is rotatably disposed inside the inner seat 43. A worm gear 433 that meshes with the turbine 432 is also rotatably disposed inside the inner seat 43. A motor 434 is fixed on the inner seat 43 and drives the worm gear 433 to rotate. A right fixed long rod 45 for fixing the other end of the bridge segment 6 is fixed to the end of the fixed shaft 44. The rotation axis of the right fixed long rod 45 coincides with the rotation axis of the left fixed long rod 34. The imaging unit 5 includes a high-speed camera 51, which is fixed to the fixed shaft 44 and faces the fixed bridge segment 6. The laser 2 faces the bridge segment 6.

[0024] In this scheme, the two sides of the bridge segment 6 are fixed by the left fixed long rod 34 and the right fixed long rod 45. The fixing method can be screw fixing. The long rods can avoid obstructing the viewing direction at the end of the bridge segment 6 when fixing the bridge segment 6; Figure 2 In the fixed-rotation section 3, the vertical frame, the horizontal rotation axis 33, and the left fixed long rod 34 intersect to form a swing point. The bridge segment 6 can rotate around the X-axis in the fixed-rotation section 3 through the rotation of the vertical frame 32 on the column 31, rotate around the Y-axis in the fixed-rotation section 3 through the rotation of the horizontal rotation axis 33 within the vertical frame 32, and rotate around the Z-axis in the fixed-rotation section 3 through the rotation of the left fixed long rod 34 on the horizontal rotation axis 33. The arc movement of the inner frame 42 on the outer frame 41 causes the bridge segment 6 to rotate around the Y-axis, and the arc movement of the inner seat 43 on the inner frame 42 causes the bridge segment 6 to rotate around the X-axis. The rotation of the fixed shaft 44 on the inner seat 43 drives the bridge segment 6 to rotate around the Z-axis. The high-speed camera 51, mounted on the fixed shaft 44, always rotates around the swing point with the bridge segment 6, so that the high-speed camera 51 always faces the fixed direction of the bridge segment 6 during the movement of the bridge segment 6, and can directionally capture the trajectory of the particles emitted by the laser 2, which can ensure the comprehensiveness and accuracy of the experimental data. This experimental device is unobstructed throughout the PIV experiment and can control the rotation of the bridge segment 6 around the three axes of XYZ at any time in the wind tunnel test to simulate the wind trajectory of the bridge segment 6 under different wind directions.

[0025] In the structure of the swing part 4, the inner frame 42 is driven to move by the first electric cylinder 412 and guided by the movement of the two sliding columns 421 in the arc-shaped sliding grooves on the upper and lower sides of the outer frame 41. This structure fixes the direction of movement of the inner frame 42 and makes the movement smooth. The inner frame 42 avoids swinging up and down under the support of the sliding columns 421. This structure serves as the first-stage rotating structure of the bridge segment 6, rotating around the Y-axis.

[0026] Driven by the second electric cylinder 424, the inner seat 43 moves along the second slide groove 4232 of the support seat 423, and the support seat 423 moves along the first slide groove 422 on the inner frame 42. The support seat 423 can serve as a support structure for the inner seat 43 and drive the inner seat 43 to move in an arc. This structure serves as the second-stage rotating structure of the bridge segment 6 to rotate around the X-axis, thus fixing the direction of movement of the inner seat 43.

[0027] Driven by the motor 434, the fixed cylinder 54 transmits rotation through the worm gear 433. This structure serves as the third-stage rotating structure of the bridge segment 6, rotating around the Z-axis. The transmission method is rapid and can effectively prevent reverse rotation.

[0028] In further proposals, such as Figure 4 As shown, the shooting unit 5 also includes a frame 52, which is rotatably mounted on the fixed shaft 44. The axis of rotation of the frame 52 coincides with the axis of the fixed shaft 44. The high-speed camera 51 has rotating rods 53 fixed at both ends. Vertical grooves 521 are opened on both sides of the frame 52. The two rotating rods 53 are slidably mounted in the vertical grooves 521. A fixed cylinder 54 is threaded onto the rotating rod 53. A locking screw 55 is threaded onto the frame 52. The locking screw 55 passes through the frame 52 and abuts against the side of the fixed cylinder 54.

[0029] In this scheme, by rotating the seat frame 52 and the high-speed camera 51, and moving the high-speed camera 51, the angle of the high-speed camera 51 toward the bridge segment 6 can be changed. The position of the high-speed camera 51 can be locked by the fixing cylinder 54 and the tightening screw 55. When the surface structure of the bridge segment 6 is irregular or when it is necessary to observe the wind direction particle trajectory from different observation angles on the surface of the bridge segment 6, this can be achieved by adjusting the position of the high-speed camera 51.

[0030] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A three-way adjustable device for a bridge segment model of a piv wind tunnel test, characterized by: The wind tunnel test cabin (1) is internally provided with a laser (2), a fixed rotating part (3), a swinging part (4) and a shooting part (5), the fixed rotating part (3) comprises a vertical column (31) vertically arranged, a vertical rotating frame (32) coaxially arranged on the vertical column (31), a horizontal rotating shaft (33) rotatably arranged in the vertical rotating frame (32), a left fixed long rod (34) for fixing the end of a bridge section (6) rotatably arranged at the end of the horizontal rotating shaft (33), and the rotation axes of the left fixed long rod (34), the horizontal rotating shaft (33) and the vertical rotating frame (32) are perpendicular to each other and intersect at one point.

2. The piv wind tunnel tested bridge segment model three- direction adjustable device according to claim 1, characterized in that: The shooting part (5) further comprises a seat frame (52) rotatably arranged on the fixed shaft (44), the rotation axis of the seat frame (52) coincides with the axis of the fixed shaft (44), the high-speed camera (51) is fixed at both ends of the fixed shaft (44) and faces the fixed bridge section (6), and the laser (2) faces the bridge section (6).

3. The piv wind tunnel tested bridge segment model three-dimensional adjustable device according to claim 1, characterized in that: Arc-shaped rail grooves (411) are respectively formed in the inner sides of the upper and lower edges of the outer frame (41), two slide columns (421) are respectively fixed to the upper and lower ends of the inner frame (42), the ends of the slide columns (421) are respectively slidably arranged in the arc-shaped rail grooves (411), first electric cylinders (412) are respectively fixed to the left and right edges of the outer frame (41), and rollers (413) are arranged at the ends of the first electric cylinders (412) and abut against the left and right outer sides of the inner frame (42).

4. The piv wind tunnel tested bridge segment model three-dimensional adjustable apparatus according to claim 1, characterized in that: The left and right inner sides of the inner frame (42) are respectively provided with vertical first sliding grooves (422), a supporting seat (423) is vertically slidably arranged on the first sliding groove (422), a groove (4231) is formed downward in the supporting seat (423), lateral second sliding grooves (4232) are formed on the two sides of the groove (4231), and cylinder shafts (431) are fixed at the two ends of the inner seat (43) and are slidably arranged in the second sliding grooves (4232); a second electric cylinder (424) is fixed to the inner bottom of the inner frame (42) and drives the supporting seat (423) to move up and down.

5. The piv wind tunnel test bridge segment model three-way adjustable device according to claim 1, wherein: The end of the fixed shaft (44) is fixed with a turbine (432), the turbine (432) is rotatably arranged in the inner seat (43), a worm (433) engaged with the turbine (432) is also rotatably arranged in the inner seat (43), an electric machine (434) is fixed to the inner seat (43) and drives the worm (433) to rotate.

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