Wind tunnel structure

Abstract

The invention provides a wind tunnel structure, relates to the technical field of aeroacoustics, and aims to solve the technical problem that the wind tunnel structure is difficult to effectively reduce the background noise of a wind tunnel and suppress the low-frequency pressure pulsation of the aeroacoustics wind tunnel. The wind tunnel structure comprises a first frame and a second frame which are arranged in parallel in a spaced mode, the first frame and the second frame are connected through a plurality of straight rods, the first frame and the second frame are each of a rectangular structure, and the area defined by the first frame is larger than that defined by the second frame; the first frame comprises two opposite first rods and two opposite second rods, and the second frame comprises two opposite first sections and two opposite second sections; the wind tunnel structure further comprises two first wall plates, two second wall plates and a plurality of first adjusting structures. One end of each first wall plate is hinged to the first section, and the other end of each first wall plate is connected to the first rod through at least one first adjusting structure. The wind tunnel is simple in structure and can effectively reduce the background noise of the wind tunnel.

Description

Technical Field

[0001] The invention relates to the technical field of aerodynamic acoustics, and in particular to a wind tunnel structure. Background Art

[0002] In aeroacoustic wind tunnels, the test environment requires not only low background noise, but also high requirements for low-frequency pressure pulsation. Especially in large-scale low-speed acoustic wind tunnels, excessive low-frequency pressure pulsation will not only affect the quality of test data, but also affect the structural safety of wind tunnel equipment and tunnel loops. The frequency of this phenomenon is usually below 20Hz. When low-frequency pressure pulsation occurs, feedback oscillations are generated between the coherent vortex structure in the shear layer of the wind tunnel opening jet and the collector. Therefore, suppressing the oscillation between the jet and the wind tunnel structure is an effective way to reduce low-frequency pressure pulsation.

[0003] Currently, one of the effective measures to reduce low-frequency pressure pulsations in aeroacoustic wind tunnels is to adjust the wall panel angle of the open jet wind tunnel structure. By changing the expansion angle, the wind tunnel jet length is changed, thereby moving the resonance to other wind speed ranges and avoiding low-frequency oscillations at the test wind speed.

[0004] In the related art, the wall panels of the aeroacoustic wind tunnel structure are mostly fixed structures. Due to design reasons, some wind tunnel structures with adjustable angles have many defects and cannot meet the requirements of suppressing the low-frequency pressure pulsation of the aeroacoustic wind tunnel and reducing the background noise of the wind tunnel. Summary of the invention

[0005] The object of the present invention is to provide a wind tunnel structure to solve the technical problem that the wind tunnel structure is difficult to effectively reduce the wind tunnel background noise and suppress the low-frequency pressure pulsation of the aeroacoustic wind tunnel.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a wind tunnel structure, comprising a first frame and a second frame arranged in parallel and at intervals, the first frame and the second frame are connected by a plurality of straight rods, the first frame and the second frame are both rectangular structures, and the area enclosed by the first frame is larger than the area enclosed by the second frame.

[0008] According to at least one embodiment of the present invention, the first frame includes two opposite first rods and two opposite second rods, and the second frame includes two opposite first sections and two opposite second sections.

[0009] According to at least one embodiment of the present invention, the wind tunnel structure further comprises two first wall panels, two second wall panels and a plurality of first adjustment structures;

[0010] One end of each of the first wall panels is hinged to the first section, and the other end is connected to the first rod through at least one of the first adjustment structures;

[0011] One end of each of the second wall panels is hinged to the second section, and the other end is connected to the second rod through at least one of the first adjustment structures.

[0012] According to at least one embodiment of the present invention, the first adjustment structure comprises a first screw and a first rotating sleeve, the first rotating sleeve has a first through hole for the first screw to pass through, and the position of the first rotating sleeve on the first screw is adjustable;

[0013] The first rotating sleeve is hinged to the first rod, and one end of the first screw rod facing away from the first rotating sleeve is hinged to the first wall plate; or,

[0014] The first rotating sleeve is hinged to the second rod, and one end of the first screw rod facing away from the first rotating sleeve is hinged to the second wall plate.

[0015] According to at least one embodiment of the present invention, the end of the first wall panel facing away from the first section has a first guide portion;

[0016] The end of the second wall facing away from the second section has a second air guide portion.

[0017] According to at least one embodiment of the present invention, the first guide portion is formed by bending the first wall plate in a direction away from another first wall plate;

[0018] The second guide portion is formed by bending the second wall plate in a direction away from the other second wall plate.

[0019] According to at least one embodiment of the present invention, the first guide portion and the second guide portion are both arc structures.

[0020] According to at least one embodiment of the present invention, a central angle corresponding to the arc structure is greater than or equal to 180°.

[0021] According to at least one embodiment of the present invention, the distance between the two first wall panels is smaller than the distance between the two first rods;

[0022] The distance between the two second wall plates is smaller than the distance between the two second rods.

[0023] According to at least one embodiment of the present invention, the second frame is a flange structure.

[0024] According to at least one embodiment of the present invention, the wind tunnel structure further includes a rectangular connecting pipe connected to an end surface of the second frame facing away from the first frame.

[0025] According to at least one embodiment of the present invention, the width of the first wall panel is greater than or equal to the distance between two of the second wall panels.

[0026] According to at least one embodiment of the present invention, the wind tunnel structure further comprises four seals and four second adjustment structures, wherein the seal comprises a plate body and a folded edge portion perpendicular to the plate body;

[0027] At least part of the plate body is attached to the inner wall surface of the corresponding second wall plate, and the folded edge portion is attached to the inner wall surface of the corresponding first wall plate;

[0028] One end of the folded edge portion is hinged to the end of the side surface of the corresponding second wall plate close to the second frame, and the other end is arranged on the corresponding second wall plate through a second adjustment structure;

[0029] The second adjustment structure comprises a second screw and a second rotating sleeve, the second rotating sleeve has a second through hole for the second screw to pass through, and the position of the second rotating sleeve on the second screw is adjustable;

[0030] The second rotating sleeve is hinged to the outer wall surface of the corresponding second wall plate, and one end of the second screw rod facing away from the second rotating sleeve is connected to the folded edge portion of the corresponding sealing member through a ball joint.

[0031] According to at least one embodiment of the present invention, the plate body is in a fan shape.

[0032] Among the one or more technical solutions provided in the exemplary embodiments of the present invention, at least one of the following beneficial effects can be achieved.

[0033] The wind tunnel structure of the exemplary embodiment of the present invention includes a first frame and a second frame which are arranged in parallel and at intervals, both of which are rectangular structures, and the two are connected by a plurality of straight rods to form a roughly trumpet-shaped structure, the first frame is located on the windward side, and the second frame is located on the leeward side, that is, the area enclosed by the first frame is larger than the area enclosed by the second frame. The first wall panels are respectively hinged on the two opposite first sections of the second frame, and the first wall panels are connected to the first rod of the first frame through the corresponding first adjustment structure; the second wall panels are respectively hinged on the two opposite second sections of the second frame, and the second wall panels are connected to the second rod of the first frame through the corresponding first adjustment structure, thereby, through the adjustment of the first adjustment structure, the expansion angle between the two opposite first wall panels and the two opposite second wall panels can be adjusted, thereby changing the wind tunnel jet length, and then moving the resonance to other wind speed ranges, avoiding low-frequency oscillation under the test wind speed.

[0034] Furthermore, when the four wall panels are adjusted outward to increase the expansion angle, a gap is formed between the first wall panel and the second wall panel, and the four gaps can be sealed by four seals, thereby preventing the gaps from being subjected to the impact of high-speed airflow and forming huge vibrations and regenerative noise. Based on this, the wind control structure of the exemplary embodiment of the present invention can effectively reduce the background noise of the wind tunnel and suppress the low-frequency pressure pulsation of the aeroacoustic wind tunnel. The wind tunnel has a simple structure, is easy to use, and is easy to install, and can ensure the sealing of the four gaps at any position within the adjustable expansion angle range. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings illustrate exemplary embodiments of the present invention and together with the description serve to explain the principles of the present invention, and these drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification;

[0036] Figure 1 is a schematic structural diagram of a first frame and a second frame according to an embodiment of the present invention;

[0037] Figure 2 is an axonometric structural schematic diagram of a wind tunnel structure according to an embodiment of the present invention;

[0038] Figure 3 is a schematic diagram of an axonometric structure of a wind tunnel structure according to an embodiment of the present invention from another perspective;

[0039] Figure 4 is a schematic diagram of an axonometric structure of a wind tunnel structure according to an embodiment of the present invention from another perspective;

[0040] Figure 5 is a schematic structural diagram of a second wall panel according to an embodiment of the present invention;

[0041] Figure 6 is a partial structural schematic diagram of a wind tunnel structure according to an embodiment of the present invention;

[0042] Figure 7 is an isometric structural schematic diagram of a first adjustment structure according to an embodiment of the present invention;

[0043] Figure 8 4 is a schematic cross-sectional structural diagram of a first adjustment structure according to an embodiment of the present invention.

[0044] Reference numerals:

[0045] 11. first wall plate; 111. first air guide portion; 12. second wall plate; 121. second air guide portion;

[0046] 21. plate body; 211. folding edge portion;

[0047] 31, first shot; 32, second shot;

[0048] 41. Paragraph 1; 42. Paragraph 2;

[0049] 50. Straight rod;

[0050] 60. Connecting pipe;

[0051] 71. first adjustment structure; 711. first screw rod; 712. first rotating sleeve; 713. first nut;

[0052] 72. Second adjustment structure; 721. Second screw rod; 722. Second rotating sleeve; 723. Second nut; 724. Ball joint. DETAILED DESCRIPTION

[0053] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0054] Figure 1 Schematic diagram of the structure of the first frame and the second frame according to an embodiment of the present invention. Figure 1 As shown, the wind tunnel structure of an exemplary embodiment of the present invention is formed by four wall panels and a frame structure, wherein the frame structure includes a first frame and a second frame which are arranged in parallel and at intervals, the first frame and the second frame are connected by a plurality of straight rods 50, the first frame and the second frame are both rectangular structures, and the area enclosed by the first frame is larger than the area enclosed by the second frame.

[0055] The rectangular plane formed by the first frame and the rectangular plane formed by the second frame are parallel to each other, and the line connecting the center points of the two is perpendicular to the plane of the first frame and the plane of the second frame. Through the connection of multiple straight rods 50, the two form a trumpet-shaped expansion structure along the direction from the second frame to the first frame.

[0056] Exemplarily, the first frame is located on the windward side of the wind tunnel structure, and the second frame is located on the leeward side of the wind tunnel structure.

[0057] Specifically, the first frame includes two opposite first rods 31 and two opposite second rods 32 , and the second frame includes two opposite first sections 41 and two opposite second sections 42 .

[0058] Figure 2 is an axonometric structural schematic diagram of a wind tunnel structure according to an embodiment of the present invention, Figure 5 Schematic diagram of the structure of the second wall panel according to an embodiment of the present invention. Figure 5As shown, the shape of the first wall panel 11 is substantially the same as the shape of the second wall panel 12 .

[0059] In some embodiments, Figure 2 As shown, two first wall panels 11 are arranged opposite to each other, one end of each first wall panel 11 is hinged to the first section 41, and the other end is connected to the first rod 31 through at least one first adjustment structure 71; two second wall panels 12 are arranged opposite to each other, one end of each second wall panel 12 is hinged to the second section 42, and the other end is connected to the second rod 32 through at least one first adjustment structure 71.

[0060] Specifically, each first wall plate 11 and the first rod 31 can be connected via one first adjustment structure 71, or via multiple first adjustment structures 71, and the number of first adjustment structures 71 is determined according to actual needs. For example, each first wall plate 11 and the first rod 31 are connected via two first adjustment structures 71.

[0061] Specifically, each second wall plate 12 and the second rod 32 can be connected via one first adjustment structure 71, or via multiple first adjustment structures 71, and the number of first adjustment structures 71 is determined according to actual needs. For example, each second wall plate 12 and the second rod 32 are connected via two first adjustment structures 71.

[0062] In practical applications, the distance between the first wall panel 11 and the first rod 31, and the distance between the second wall panel 12 and the second rod 32 can be adjusted by adjusting the length of the first adjustment structure 71, that is, the four wall panels can be moved closer to or expanded to achieve continuous adjustment of the wall panel expansion angle, and the wind tunnel jet length is changed, so as to move the resonance to other wind speed ranges and avoid low-frequency oscillations under the test wind speed. The continuous adjustment of the expansion angle can meet the demand for suppressing low-frequency pressure pulsations under the continuously adjustable test wind speed.

[0063] Figure 7 is an isometric structural schematic diagram of a first adjustment structure according to an embodiment of the present invention;

[0064] Figure 8 Schematic diagram of the cross-sectional structure of the first adjustment structure according to an embodiment of the present invention. Figure 7 and Figure 8 As shown, the first adjustment structure 71 includes a first screw rod 711 and a first rotating sleeve 712. The first rotating sleeve 712 has a first through hole for the first screw rod 711 to pass through, and the position of the first rotating sleeve 712 on the first screw rod 711 is adjustable; the first rotating sleeve 712 is hinged to the first rod 31, and the end of the first screw rod 711 facing away from the first rotating sleeve 712 is hinged to the first wall panel 11.

[0065] In practical applications, two ear plates are provided on the first rod 31, and a pin is fixed on each ear plate. The pin extends into the axial hole of the first rotating sleeve 712 provided between the two ear plates to realize the hinge connection between the first rotating sleeve 712 and the first rod 31. One end of the first screw rod 711 is hinged to the ear plate provided on the outer wall surface of the first wall plate 11 through a pin, and the other end passes through the first through hole of the first rotating sleeve 712. The first rotating sleeve 712 is fixed at the corresponding position of the first screw rod 711 through two first nuts 713. When it is necessary to adjust the position of the first rotating sleeve 712 on the first screw rod 711, it is necessary to loosen the two first nuts 713 and then move the first rotating sleeve 712. After reaching the corresponding position, the two first nuts 713 can be locked to fix the position of the first rotating sleeve 712. Based on this, the continuous adjustment of the expansion angle of the first wall plate 11 can be realized.

[0066] In the first adjustment structure 71 connecting the second wall plate 12 and the second rod 32, the first rotating sleeve 712 is hinged to the second rod 32, and the end of the first screw rod 711 away from the first rotating sleeve 712 is hinged to the second wall plate 12. The adjustment process of the expansion angle of the second wall plate 12 is the same as that of the expansion angle of the first wall plate 11, which will not be repeated here.

[0067] Figure 3 is a schematic diagram of an axonometric structure of a wind tunnel structure according to an embodiment of the present invention from another perspective; Figure 4 FIG. 2 is a schematic diagram of an axonometric structure of a wind tunnel structure according to an embodiment of the present invention from another perspective. Figure 2-Figure 4 As shown, in the wind tunnel structure of the exemplary embodiment of the present invention, the end of the first wall plate 11 away from the first section 41 has a first guide portion 111 ; the end of the second wall plate 12 away from the second section 42 has a second guide portion 121 .

[0068] The first guide portion 111 and the second guide portion 121 are respectively provided on the windward side of the first wall plate 11 and the second wall plate 12 to achieve smooth transition of airflow.

[0069] Exemplarily, the first guide portion 111 is formed by bending the first wall plate 11 in a direction away from the other first wall plate 11 ; the second guide portion 121 is formed by bending the second wall plate 12 in a direction away from the other second wall plate 12 .

[0070] For example, the first air guide portion 111 and the second air guide portion 121 are both arc structures, and the corresponding central angle of the two is greater than or equal to 180°. Exemplarily, the arc structure is a semicircular structure, which can guide the airflow from the circumferential edge of the expansion opening to the rear of the second frame, thereby effectively reducing the background noise of the wind tunnel.

[0071] Exemplarily, a sound absorbing layer is attached to the inner wall surface of the first wall plate 11 and the second wall plate 12 to reduce the background noise of the wind tunnel. The material of the sound absorbing layer can be porous ceramics, mineral wool, etc.

[0072] In some embodiments, Figure 3 As shown, the distance between the two first wall plates 11 is smaller than the distance between the two first rods 31 ; and the distance between the two second wall plates 12 is smaller than the distance between the two second rods 32 .

[0073] In actual applications, the four wall panels are all located inside the first frame, and the first adjustment structure 71 of each wall panel is arranged on the outer wall surface of the corresponding wall panel, so that the first frame is not in the expansion opening surrounded by each wall panel, but is located outside the expansion opening and does not affect the passage of airflow in the expansion opening.

[0074] like Figure 1 As shown, the second frame can be a flange structure, and the first section 41 and the second section 42 are rectangular plate structures to form a flange structure. Through the flange structure, the rectangular connecting pipe 60 can be conveniently installed on the end face of the second frame away from the first frame, thereby forming a channel for airflow to flow through the expansion port.

[0075] like Figure 4 As shown, exemplarily, the width of the first wall panel 11 is greater than or equal to the distance between the two second wall panels 12 .

[0076] The width direction of the first wall panel 11 refers to the distribution direction from one second wall panel 12 to another second wall panel 12. When the two second wall panels 12 form the maximum expansion angle, they are also between the two first wall panels 11 and will not exceed the above range, which can provide corresponding basic conditions for sealing the gap between the first wall panel 11 and the second wall panel 12.

[0077] Figure 6 FIG. 1 is a schematic diagram of a partial structure of a wind tunnel structure according to an embodiment of the present invention. Figure 2 , Figure 3 as well as Figure 6 As shown, the wind tunnel structure of the exemplary embodiment of the present invention also includes four seals and four second adjustment structures 72, the seal includes a plate body 21 and a folded edge portion 211 perpendicular to the plate body 21; at least part of the plate body 21 is attached to the inner wall surface of the corresponding second wall panel 12, and the folded edge portion 211 is attached to the inner wall surface of the corresponding first wall panel 11; one end of the folded edge portion 211 is hinged to the end of the side surface of the corresponding second wall panel 12 close to the second frame, and the other end is arranged on the corresponding second wall panel 12 through the second adjustment structure 72.

[0078] The second adjustment structure 72 includes a second screw rod 721 and a second rotating sleeve 722 . The second rotating sleeve 722 has a second through hole for the second screw rod 721 to pass through. The position of the second rotating sleeve 722 on the second screw rod 721 is adjustable.

[0079] The second rotating sleeve 722 is hinged to the outer wall surface of the corresponding second wall plate 12 , and one end of the second screw rod 721 away from the second rotating sleeve 722 is connected to the folded edge portion 211 of the corresponding sealing component through a ball joint 724 .

[0080] In actual applications, the connection between the second screw 721 and the second rotating sleeve 722 in the second adjusting structure 72 is limited in position by two second nuts 723, and the connection method is the same as the connection method between the first screw 711 and the first rotating sleeve 712 in the first adjusting structure 71, which will not be repeated here.

[0081] Two ear plates are arranged at the position of the outer wall surface of the second wall plate 12 near the second guide part 121, and the second rotating sleeve 722 is hinged between the two ear plates through a pin. The position of the second rotating sleeve 722 on the second screw rod 721 can be adjusted. The other end of the second screw rod 721 has a ball head, and a ball seat is arranged on the folding part 211. The ball head and the ball seat form a ball joint 724, so as to realize the movable connection between the second screw rod 721 and the folding part 211.

[0082] When the first wall panel 11 is at the maximum expansion angle, and the folded edge portion 211 is attached to the inner wall surface of the first wall panel 11, a portion of the plate body 21 is still attached to the inner wall surface of the second wall panel 12, thereby forming a blockage of the gap between the first wall panel 11 and the second wall panel 12. It can be seen that no matter how large the expansion angle of the first wall panel 11 is, by adjusting the length of the second screw rod 721 between the first wall panel 11 and the second wall panel 12, the folded edge portion 211 can also be attached to the inner wall surface of the first wall panel 11, and a portion of the plate body 21 is always attached to the inner wall surface of the corresponding second wall panel 12, thereby completing the blockage of the gap.

[0083] Exemplarily, the width and shape of the hem portion 211 are the same as the side of the second wall panel 12, and it can be completely attached to the side of the second wall panel 12. It can be understood that the ball seat of the hem portion 211 is arranged at the outer edge of the hem portion 211, rather than being directly arranged at a position where the hem portion 211 is opposite to the side of the second wall panel 12.

[0084] Exemplarily, a sealing strip may be provided on the folded edge portion 211 , so that the folded edge portion 211 is more sealed when it is attached to the inner wall surface of the first wall panel 11 .

[0085] Exemplarily, the plate body 21 is fan-shaped, that is, the windward surface of the plate body 21 is an arc-shaped structure, so that when the airflow blows onto the plate body 21, the background noise of the wind tunnel can be reduced compared with a straight windward surface.

[0086] As can be seen from the above, the expansion angle of each wall panel is continuously adjustable, and the four corner gaps of the upper, lower, left and right wall panels are sealed with packaging parts. The following problems can be avoided: the gaps between the wall panels will form huge vibrations and regenerative noises under the impact of high-speed airflow, which will affect the background noise in the aeroacoustic wind tunnel on the one hand, and the suppression effect of low-frequency pressure pulsation on the other hand will be greatly reduced. Therefore, the wind tunnel structure of the exemplary embodiment of the present invention is simple in structure and more convenient to use, and can ensure the sealing of the four corners at any position within the adjustable angle range of the collector.

[0087] It should be understood by those skilled in the art that the above embodiments are only for the purpose of clearly illustrating the present invention, and are not intended to limit the scope of the present invention. For those skilled in the art, other changes or modifications may be made based on the above disclosure, and these changes or modifications are still within the scope of the present invention.

Claims

1. A wind tunnel structure, characterized in that: It comprises a first frame and a second frame which are arranged in parallel and at intervals, wherein the first frame and the second frame are connected via a plurality of straight rods, the first frame and the second frame are both rectangular structures, and the area enclosed by the first frame is larger than the area enclosed by the second frame.

2. The wind tunnel structure according to claim 1, characterized in that: The first frame includes two opposite first rods and two opposite second rods, and the second frame includes two opposite first sections and two opposite second sections.

3. The wind tunnel structure according to claim 2, characterized in that: The wind tunnel structure also includes two first wall panels, two second wall panels and a plurality of first adjustment structures; One end of each of the first wall panels is hinged to the first section, and the other end is connected to the first rod through at least one of the first adjustment structures; One end of each of the second wall panels is hinged to the second section, and the other end is connected to the second rod through at least one of the first adjustment structures.

4. The wind tunnel structure according to claim 3, characterized in that: Each of the first wall panels is connected to the first rod via two of the first adjustment structures; Each of the second wall panels is connected to the second rod via two of the first adjustment structures.

5. The wind tunnel structure according to claim 3, characterized in that: The first adjustment structure includes a first screw and a first rotating sleeve, the first rotating sleeve has a first through hole for the first screw to pass through, and the position of the first rotating sleeve on the first screw is adjustable; The first rotating sleeve is hinged to the first rod, and one end of the first screw rod facing away from the first rotating sleeve is hinged to the first wall plate; or, The first rotating sleeve is hinged to the second rod, and one end of the first screw rod facing away from the first rotating sleeve is hinged to the second wall plate.

6. The wind tunnel structure according to claim 5, characterized in that: The distance between the two first wall plates is smaller than the distance between the two first rods; The distance between the two second wall plates is smaller than the distance between the two second rods.

7. The wind tunnel structure according to claim 5, characterized in that: The second frame is a flange structure.

8. The wind tunnel structure according to claim 5, characterized in that: The wind tunnel structure further includes a rectangular connecting pipe connected to an end surface of the second frame facing away from the first frame.

9. The wind tunnel structure according to claim 5, characterized in that: The width of the first wall plate is greater than or equal to the distance between two of the second wall plates.

10. The wind tunnel structure according to claim 5, characterized in that: The inner wall surfaces of the first wall panel and the second wall panel are both provided with sound absorbing layers.

Images