Device for eliminating boundary layer in wind tunnel and wind tunnel

Abstract

The present invention discloses a device for eliminating boundary layer in a wind tunnel. The wind tunnel includes an experimental section and a contraction section directly connected, with the contraction section located upstream of the experimental section. A main fan is provided in the wind tunnel and is located upstream of the contraction section. The device for eliminating boundary layer in the wind tunnel includes a bypass duct. The inlet of the bypass duct communicates with the contraction section, and the outlet of the bypass duct communicates with the experimental section and is located on the inner surface of the bottom wall of the experimental section, so that the bypass air flow coming out of the bypass duct is in the same direction as the main air flow coming out of the contraction section. This ensures the technical indicators of the main air flow, does not affect the quality of the main air flow, and eliminates the air flow boundary layer at the bottom of the experimental section. The device for eliminating boundary layer in the wind tunnel of the present invention can effectively eliminate the air flow boundary layer at the bottom of the experimental section, does not affect the quality of the main air flow, and has a low cost. The present invention also discloses a wind tunnel.

Description

Technical Field

[0001] The present invention relates to the technical field of wind tunnels, and in particular to a device for eliminating boundary layers in a wind tunnel and a wind tunnel. Background Art

[0002] As Figures 1 to 3 shown, a prior art wind tunnel includes an experimental section 300 and a contraction section 200 that are directly connected. The contraction section 200 is located upstream of the experimental section 300. A main fan 100 is provided in the wind tunnel, and the main fan 100 is located upstream of the contraction section 200. When the main fan 100 operates, the blown air flow passes through the contraction section 200 and enters the experimental section 300. In order to eliminate the boundary layer on the bottom surface of the experimental section 300, the common practice in the industry is generally to separately provide an exhaust fan 400 below the experimental section 300 to suck the air flow at the bottom of the experimental section 400. In this way, additional equipment is required, and the direction of the suction air flow 500 is opposite to the direction of the main air flow 600, resulting in poor boundary layer elimination effect and affecting the air flow quality of the experimental section 300, thereby affecting the experimental accuracy. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. For this reason, an object of the present invention is to provide a device for eliminating boundary layers in a wind tunnel, which can effectively eliminate the boundary layer of the air flow at the bottom of the experimental section, does not affect the quality of the main air flow, and has low cost.

[0004] According to an embodiment of one aspect of the present invention, a device for eliminating boundary layers in a wind tunnel, the wind tunnel includes an experimental section and a contraction section that are directly connected, the contraction section is located upstream of the experimental section, a main fan is provided in the wind tunnel, and the main fan is located upstream of the contraction section. The device for eliminating boundary layers in the wind tunnel includes:

[0005] A bypass duct, an inlet of the bypass duct is communicated with the contraction section, an outlet of the bypass duct is communicated with the experimental section and is located on the inner surface of the bottom wall of the experimental section, so that the bypass air flow coming out of the bypass duct is in the same direction as the main air flow coming out of the contraction section. Ensure the technical indicators of the main air flow, do not affect the quality of the main air flow, and eliminate the boundary layer of the air flow at the bottom of the experimental section.

[0006] An apparatus for eliminating the boundary layer in a wind tunnel according to an embodiment of one aspect of the present invention. The wind tunnel is a closed-loop air flow circuit. When the main fan operates, it causes the air flow to circulate in the wind tunnel. The air flow blown by the main fan enters the test section through the contraction section, providing environmental conditions for the test section. By providing a bypass duct, the air flow passing through the contraction section is diverted. After diversion, a part is the main air flow for experimental testing, and the other part is the bypass air flow that is blown out from the bottom surface of the test section through the bypass duct. Moreover, the bypass air flow coming out of the bypass duct is in the same direction as the main air flow coming out of the contraction section. The bypass air flow can more effectively eliminate the boundary layer of the air flow at the bottom of the test section without affecting the quality of the main air flow, ensuring the technical indicators of the main air flow and the experimental accuracy. At the same time, there is no need to add additional equipment such as the boundary layer suction device in the prior art, reducing the construction and subsequent maintenance costs. In addition, the apparatus for eliminating the boundary layer in the wind tunnel according to an embodiment of one aspect of the present invention has a simple structure and low cost.

[0007] According to an embodiment of one aspect of the present invention, the inlet of the bypass duct is connected to the bottom of the contraction section.

[0008] According to some embodiments of one aspect of the present invention, the apparatus for eliminating the boundary layer in the wind tunnel further includes an adjusting damper, and the adjusting damper is arranged at the inlet of the bypass duct to close and open the inlet.

[0009] According to a further embodiment of one aspect of the present invention, there are two adjusting dampers, and the two adjusting dampers are respectively arranged on opposite sides of the inlet of the bypass duct.

[0010] According to a further embodiment of one aspect of the present invention, the adjusting damper is connected to a control system, and the control system controls the opening degree of the adjusting damper.

[0011] According to a still further embodiment of one aspect of the present invention, the control system also controls the rotational speed of the main fan to control the seamless docking of the bypass air flow and the main air flow.

[0012] An apparatus for eliminating the boundary layer in a wind tunnel according to an embodiment of another aspect of the present invention. The wind tunnel includes a directly connected test section and a contraction section. The contraction section is located upstream of the test section. A main fan is arranged in the wind tunnel, and the main fan is located upstream of the contraction section. It is characterized in that the apparatus for eliminating the boundary layer in the wind tunnel includes:

[0013] A bypass duct, the inlet of the bypass duct is connected to the bottom of the contraction section, and the outlet of the bypass duct is connected to the test section and is located on the inner surface of the bottom wall of the test section, so that the bypass air flow coming out of the bypass duct is in the same direction as the main air flow coming out of the contraction section.

[0014] Adjusting air dampers, there are two of the adjusting air dampers, and the two adjusting air dampers are respectively arranged on opposite sides of the entrance of the bypass air duct to close and open the entrance; the two adjusting air dampers are connected to a control system, the control system controls the opening degree of the adjusting air dampers, and the control system also controls the rotation speed of the main fan to control the seamless docking of the bypass air flow and the main air flow.

[0015] According to the device for eliminating the boundary layer in a wind tunnel according to another embodiment of the present invention, the wind tunnel is a closed-loop air flow circuit. When the main fan operates, it makes the air flow circulate in the wind tunnel. The air flow blown out by the main fan enters the experimental section through the contraction section, providing environmental conditions for the experimental section; by setting a bypass air duct, the air flow flowing through the contraction section is shunted. After shunting, a part is the main air flow for experimental testing, and the other part is the bypass air flow that is blown out from the bottom surface of the experimental section through the bypass air duct, and the bypass air flow coming out of the bypass air duct is in the same direction as the main air flow coming out of the contraction section. By setting two adjusting air dampers at the entrance of the bypass air duct, controlling the opening and closing of the adjusting air dampers through a specific control system, and adjusting the rotation speed of the main fan in the wind tunnel, seamless docking of the regulation of the bypass air flow and the main air flow is achieved. Utilizing the bypass air flow can more effectively eliminate the boundary layer of the air flow at the bottom of the experimental section without affecting the quality of the main air flow, ensuring the technical indicators of the main air flow and the experimental accuracy; at the same time, there is no need to add additional equipment such as the boundary layer suction device in the prior art, reducing the construction and later maintenance costs. In addition, the device for eliminating the boundary layer in the wind tunnel according to another embodiment of the present invention has a simple structure and low cost.

[0016] The present invention also proposes a wind tunnel.

[0017] The wind tunnel according to an embodiment of the present invention includes the device for eliminating the boundary layer in the wind tunnel according to any one of the embodiments of one aspect of the present invention, or includes the device for eliminating the boundary layer in the wind tunnel according to the embodiment of another aspect of the present invention.

[0018] The additional aspects and advantages of the present invention will be partially given in the following description, partially will become obvious from the following description, or will be understood through the practice of the present invention. Description of the Drawings

[0019] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

[0020] Figure 1 It is a schematic diagram of a wind tunnel of the prior art.

[0021] Figure 2 It is Figure 1 The sectional view at A - A in

[0022] Figure 3 It isFigure 2 Schematic enlarged view at position B in [the figure].

[0023] Figure 4 Schematic view of the wind tunnel according to an embodiment of the present invention.

[0024] Figure 5 is Figure 4 Schematic cross-sectional view at C-C in [the figure].

[0025] Figure 6 is Figure 5 Schematic enlarged view at position E in [the figure].

[0026] Figure 7 is Figure 4 Schematic cross-sectional view at D-D in [the figure], wherein two regulating dampers are shown in the fully open state.

[0027] Figure 8 is Figure 4 Schematic cross-sectional view at D-D in [the figure], wherein two regulating dampers are shown in the half-open state.

[0028] Reference numerals:

[0029] Main fan 1, contraction section 2, test section 3, bypass duct 4, inlet 401, outlet 402

[0030] Bypass air flow 5, main air flow 6, regulating damper 7 Detailed implementation manners

[0031] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention.

[0032] Next, in conjunction with Figures 4 to 8 to describe an apparatus for eliminating boundary layer in a wind tunnel according to an embodiment of one aspect of the present invention.

[0033] As Figures 4 to 8 shown, an apparatus for eliminating boundary layer in a wind tunnel according to an embodiment of one aspect of the present invention, the wind tunnel includes a directly connected test section 3 and a contraction section 2, the contraction section 2 is located upstream of the test section 3, a main fan 1 is provided in the wind tunnel, the main fan 1 is located upstream of the contraction section 2, the apparatus for eliminating boundary layer in the wind tunnel includes a bypass duct 4, an inlet 401 of the bypass duct 4 is communicated with the contraction section 2, an outlet 402 of the bypass duct 4 is communicated with the test section 3 and is located on the inner surface of the bottom wall of the test section 3, so that the bypass air flow 5 coming out of the bypass duct is in the same direction as the main air flow 6 coming out of the contraction section 2.

[0034] An apparatus for eliminating the boundary layer in a wind tunnel according to an embodiment of one aspect of the present invention. The wind tunnel is a closed-loop air flow circuit. When the main fan 1 operates, it causes the air flow to circulate in the wind tunnel. The air flow blown by the main fan 1 passes through the contraction section 2 and enters the test section 3, providing environmental conditions for the test section 3. By providing a bypass duct 4, the air flow passing through the contraction section 2 is diverted. After diversion, a part is the main air flow 6 for experimental testing, and the other part is the bypass air flow 5 that is blown out from the bottom surface of the test section 3 through the bypass duct 4. And the bypass air flow 5 coming out of the bypass duct is in the same direction as the main air flow 6 coming out of the contraction section 2. The bypass air flow can more effectively eliminate the boundary layer of the air flow at the bottom of the test section 3 and does not affect the quality of the main air flow 6, ensuring the technical indicators of the main air flow 6 and the experimental accuracy. At the same time, there is no need to add additional equipment such as the boundary layer suction device in the prior art, reducing the construction and subsequent maintenance costs. In addition, the apparatus for eliminating the boundary layer in the wind tunnel according to an embodiment of one aspect of the present invention has a simple structure and low cost.

[0035] According to an embodiment of one aspect of the present invention, the inlet 401 of the bypass duct 4 is connected to the bottom of the contraction section 2. In this way, the position of the bypass duct 4 is set more reasonably.

[0036] According to some embodiments of one aspect of the present invention, the apparatus for eliminating the boundary layer in the wind tunnel further includes an adjusting damper 7. The adjusting damper 7 is arranged at the inlet 401 of the bypass duct 4 to close and open the inlet 401. It can be understood that by arranging the adjusting damper 7 at the inlet 401 of the bypass duct, the opening degree of the damper 7 can be adjusted according to actual needs to effectively eliminate the boundary layer of the air flow at the bottom of the test section 3 while not affecting the quality of the main air flow 6 and ensuring the technical indicators of the main air flow 6.

[0037] According to a further embodiment of one aspect of the present invention, there are two adjusting dampers 7, and the two adjusting dampers 7 are respectively arranged on opposite sides of the inlet 401 of the bypass duct 4. By arranging two adjusting dampers 7, the inlet 401 of the bypass duct 4 can be opened or closed.

[0038] According to a further embodiment of one aspect of the present invention, the adjusting damper 7 is connected to a control system, and the control system controls the opening degree of the adjusting damper 7. In this way, automatic adjustment of the damper can be achieved.

[0039] According to a still further embodiment of one aspect of the present invention, the control system also controls the rotation speed of the main fan 1 to control the seamless docking of the bypass air flow 5 and the main air flow 6, ensuring the technical indicators of the main air flow 6 and eliminating the boundary layer of the air flow at the bottom of the test section 3.

[0040] The following will be described in conjunction with Figures 4 to 8 an apparatus for eliminating the boundary layer in a wind tunnel according to an embodiment of another aspect of the present invention.

[0041] As Figures 4 to 8As shown in the figure, a device for eliminating the boundary layer in a wind tunnel according to another embodiment of the present invention. The wind tunnel includes an experimental section 3 and a contraction section 2 that are directly connected. The contraction section 2 is located upstream of the experimental section 3. A main fan 1 is provided in the wind tunnel, and the main fan 1 is located upstream of the contraction section 2. The device for eliminating the boundary layer in the wind tunnel includes a bypass duct 4 and a regulating damper 7. Among them, the inlet 401 of the bypass duct 4 is communicated with the bottom of the contraction section 2, and the outlet 402 of the bypass duct 4 is communicated with the experimental section 3 and is located on the inner surface of the bottom wall of the experimental section 3, so that the bypass air flow 5 coming out of the bypass duct is in the same direction as the main air flow 6 coming out of the contraction section 2. There are two regulating dampers 7, and the two regulating dampers 7 are respectively arranged on the opposite sides of the inlet 401 of the bypass duct 4 to close and open the inlet 401. The two regulating dampers 7 are connected to a control system. The control system controls the opening degree of the regulating damper 7, and the control system also controls the rotation speed of the main fan 1 to control the seamless docking of the bypass air flow 5 and the main air flow 6.

[0042] The device for eliminating the boundary layer in the wind tunnel according to another embodiment of the present invention. The wind tunnel is an air flow closed-loop circuit. When the main fan 1 operates, it makes the air flow circulate in the wind tunnel. The air flow blown out by the main fan 1 passes through the contraction section 2 and enters the experimental section 3 to provide environmental conditions for the experimental section 3. By setting the bypass duct 4, the air flow flowing through the contraction section 2 is shunted. After shunting, a part is the main air flow 6 for experimental testing, and the other part is the bypass air flow 5 that is blown out from the bottom surface of the experimental section 3 through the bypass duct 4, and the bypass air flow 5 coming out of the bypass duct is in the same direction as the main air flow 6 coming out of the contraction section 2. By setting two regulating dampers 7 at the inlet 401 of the bypass duct, controlling the opening and closing of the regulating damper 7 through a specific control system, and adjusting the rotation speed of the main fan 1 in the wind tunnel, seamless docking of the regulation of the bypass air flow 5 and the main air flow 6 is achieved. Using the bypass air flow can more effectively eliminate the air flow boundary layer at the bottom of the experimental section 3 without affecting the quality of the main air flow 6, ensuring the technical indicators of the main air flow 6 and ensuring the experimental accuracy. At the same time, there is no need to add additional equipment such as the boundary layer suction device in the prior art, reducing the construction and later maintenance costs. In addition, the device for eliminating the boundary layer in the wind tunnel according to another embodiment of the present invention has a simple structure and low cost.

[0043] The present invention also proposes a wind tunnel.

[0044] The wind tunnel according to the embodiment of the present invention includes the device for eliminating the boundary layer in the wind tunnel according to any one of the embodiments of one aspect of the present invention, or includes the device for eliminating the boundary layer in the wind tunnel according to another aspect of the present invention.

[0045] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0046] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A device for eliminating the boundary layer in a wind tunnel, the wind tunnel comprising an experimental section and a contraction section directly connected, the contraction section being located upstream of the experimental section, a main fan being provided in the wind tunnel, the main fan being located upstream of the contraction section, characterized in that, The wind tunnel is an air flow closed-loop circuit. The device for eliminating the boundary layer in the wind tunnel includes: A bypass air duct. The inlet of the bypass air duct is connected to the contraction section. The outlet of the bypass air duct is connected to the test section and is located on the inner surface of the bottom wall of the test section, so that the bypass air flow coming out of the bypass air duct is in the same direction as the main air flow coming out of the contraction section, ensuring the technical indicators of the main air flow, not affecting the quality of the main air flow, and eliminating the air flow boundary layer at the bottom of the test section.

2. The device for eliminating the boundary layer in the wind tunnel according to claim 1, wherein The inlet of the bypass air duct is connected to the bottom of the contraction section.

3. The device for eliminating the boundary layer in the wind tunnel according to claim 1 or 2, characterized in that, The device for eliminating the boundary layer in the wind tunnel further includes an adjusting damper. The adjusting damper is arranged at the inlet of the bypass air duct to close and open the inlet.

4. The device for eliminating the boundary layer in a wind tunnel according to claim 3, characterized in that, There are two adjusting dampers, and the two adjusting dampers are respectively arranged on the opposite sides of the inlet of the bypass air duct.

5. The device for eliminating the boundary layer in a wind tunnel according to claim 3, characterized in that, The adjusting damper is connected to a control system, and the control system controls the opening degree of the adjusting damper.

6. The device for eliminating the boundary layer in a wind tunnel according to claim 5, characterized in that, The control system also controls the rotational speed of the main fan to control the seamless docking of the bypass air flow and the main air flow.

7. A device for eliminating the boundary layer in a wind tunnel, the wind tunnel comprising an experimental section and a contraction section directly connected, the contraction section being located upstream of the experimental section, a main fan being provided in the wind tunnel, the main fan being located upstream of the contraction section, characterized in that, The wind tunnel is an air flow closed-loop circuit. The device for eliminating the boundary layer in the wind tunnel includes: A bypass air duct. The inlet of the bypass air duct is connected to the bottom of the contraction section. The outlet of the bypass air duct is connected to the test section and is located on the inner surface of the bottom wall of the test section, so that the bypass air flow coming out of the bypass air duct is in the same direction as the main air flow coming out of the contraction section; An adjusting damper. There are two adjusting dampers, and the two adjusting dampers are respectively arranged on the opposite sides of the inlet of the bypass air duct to close and open the inlet; the two adjusting dampers are connected to a control system, and the control system controls the opening degree of the adjusting damper. The control system also controls the rotational speed of the main fan to control the seamless docking of the bypass air flow and the main air flow.

8. A wind tunnel, characterized in that, It includes the device for eliminating the boundary layer in the wind tunnel as described in any one of claims 1-6, or includes the device for eliminating the boundary layer in the wind tunnel as described in claim 7.

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