CN111623949A - Device for eliminating boundary layer in wind tunnel and wind tunnel - Google Patents

Abstract

The invention discloses a device for eliminating a boundary layer in a wind tunnel, which comprises an experimental section and a contraction section which are directly connected, wherein the contraction section is positioned at the upstream of the experimental section, a main fan is arranged in the wind tunnel and positioned at the upstream of the contraction section, the device for eliminating the boundary layer in the wind tunnel comprises a bypass air channel, the inlet of the bypass air channel is communicated with the contraction section, the outlet of the bypass air channel is communicated with the experimental section and positioned on the inner surface of the bottom wall of the experimental section, so that bypass air flow coming out of the bypass air channel and main air flow coming out of the contraction section are in the same direction. The technical index of the main air flow is ensured, the quality of the main air flow is not influenced, and the air flow boundary layer at the bottom of the experimental section is eliminated. The boundary layer eliminating device in the wind tunnel can effectively eliminate the airflow boundary layer at the bottom of the experimental section, does not influence the quality of the main airflow, and has low cost. The invention also discloses a wind tunnel.

Description

Device for eliminating boundary layer in wind tunnel and wind tunnel

Technical Field

The invention relates to the technical field of wind tunnels, in particular to a device for eliminating a boundary layer in a wind tunnel and the wind tunnel.

Background

As shown in fig. 1 to fig. 3, the wind tunnel in the prior art includes an experimental section 300 and a contraction section 200 directly connected to each other, the contraction section 200 is located at an upstream of the experimental section 300, a main fan 100 is disposed in the wind tunnel, the main fan 100 is located at an upstream of the contraction section 200, and when the main fan 100 works, blown air flows enter the experimental section 300 through the contraction section 200. In order to eliminate the boundary layer on the bottom surface of the experimental section 300, the prior art in the industry generally arranges the exhaust fan 400 at the lower part of the experimental section 300 separately to suck the airflow at the bottom of the experimental section 400, thus additional equipment is needed, the direction of the sucked airflow 500 is opposite to the direction of the main airflow 600, the boundary layer eliminating effect is poor, and the airflow quality of the experimental section 300 is affected, thereby affecting the experimental precision.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, one objective of the present invention is to provide a boundary layer eliminating device in a wind tunnel, which can effectively eliminate the boundary layer of the airflow at the bottom of the experimental section, does not affect the quality of the main airflow, and is low in cost.

According to an embodiment of one aspect of the present invention, a boundary layer eliminating device in a wind tunnel includes an experimental section and a contraction section which are directly connected, the contraction section is located at an upstream of the experimental section, a main fan is disposed in the wind tunnel, the main fan is located at an upstream of the contraction section, and the boundary layer eliminating device in the wind tunnel includes:

and the inlet of the bypass air channel is communicated with the contraction section, and the outlet of the bypass air channel is communicated with the experiment section and is positioned on the inner surface of the bottom wall of the experiment section, so that bypass airflow coming out of the bypass air channel and main airflow coming out of the contraction section are in the same direction. The technical index of the main air flow is ensured, the quality of the main air flow is not influenced, and the air flow boundary layer at the bottom of the experimental section is eliminated.

According to the device for eliminating the boundary layer in the wind tunnel, which is disclosed by the embodiment of the invention, on one hand, the wind tunnel is an airflow closed loop, when the main fan works, airflow circularly flows in the wind tunnel, and the airflow blown out by the main fan enters the experimental section through the contraction section, so that the environmental condition is provided for the experimental section; by arranging the bypass air duct, the air flow passing through the contraction section is divided, one part of the divided air flow is the main air flow for experimental testing, the other part of the divided air flow is the bypass air flow blown out from the bottom surface of the experimental section through the bypass air duct, the bypass air flow coming out from the bypass air duct and the main air flow coming out from the contraction section are in the same direction, the boundary layer of the air flow at the bottom of the experimental section can be effectively eliminated by utilizing the bypass air flow, the quality of the main air flow is not influenced, the technical index of the main air flow can be ensured, and the experimental precision is ensured; meanwhile, extra equipment such as a boundary layer suction device in the prior art is not needed, and the construction cost and the later maintenance cost are reduced. In addition, on one hand, the device for eliminating the boundary layer in the wind tunnel is simple in structure and low in cost.

According to one embodiment of one aspect of the invention, the inlet of the bypass duct communicates with the bottom of the convergent section.

According to some embodiments of an aspect of the present invention, the means for eliminating boundary layers in the wind tunnel further comprises a damper disposed at the inlet of the bypass duct to close and open the inlet.

According to a further embodiment of the one aspect of the present invention, there are two of the damper doors, and the two damper doors are respectively disposed on opposite sides of the inlet of the bypass duct.

According to a further embodiment of an aspect of the invention, the damper is connected to a control system, which controls the opening of the damper.

According to a still further embodiment of an aspect of the present invention, the control system further controls the main fan speed to control the bypass airflow to seamlessly interface with the main airflow.

According to another aspect of the present invention, a boundary layer eliminating device in a wind tunnel comprises an experimental section and a contraction section which are directly connected, wherein the contraction section is located at an upstream of the experimental section, a main fan is arranged in the wind tunnel, and the main fan is located at an upstream of the contraction section, and the boundary layer eliminating device in the wind tunnel comprises:

the inlet of the bypass air channel is communicated with the bottom of the contraction section, and the outlet of the bypass air channel is communicated with the experiment section and is positioned on the inner surface of the bottom wall of the experiment section, so that bypass airflow coming out of the bypass air channel and main airflow coming out of the contraction section are in the same direction;

the two air adjusting doors are respectively arranged on two opposite sides of the inlet of the bypass air channel so as to close and open the inlet; the two air adjusting doors are connected with a control system, the control system controls the opening degree of the air adjusting doors, and the control system also controls the rotating speed of the main fan so as to control the seamless butt joint of the bypass airflow and the main airflow.

According to the device for eliminating the boundary layer in the wind tunnel, which is disclosed by the embodiment of the invention, the wind tunnel is an airflow closed loop, when the main fan works, airflow circularly flows in the wind tunnel, and the airflow blown out by the main fan enters the experimental section through the contraction section, so that the environmental condition is provided for the experimental section; by arranging the bypass air duct, the air flow passing through the contraction section is divided, one part of the divided air flow is the main air flow for experimental test, the other part of the divided air flow is the bypass air flow blown out from the bottom surface of the experimental section through the bypass air duct, the bypass air flow coming out from the bypass air duct and the main air flow coming out from the contraction section are in the same direction, two air dampers are arranged at the inlets of the bypass air duct, the opening of the air dampers are controlled through a specific control system, the rotating speed of a main fan in the air tunnel is adjusted, the seamless butt joint of the bypass air flow and the main air flow regulation is achieved, the boundary layer of the air flow at the bottom of the experimental section can be effectively eliminated by utilizing the bypass air flow, the quality of the main air flow is not influenced, the technical; meanwhile, extra equipment such as a boundary layer suction device in the prior art is not needed, and the construction cost and the later maintenance cost are reduced. In addition, the device for eliminating the boundary layer in the wind tunnel in the embodiment of the invention has simple structure and low cost.

The invention further provides a wind tunnel.

A wind tunnel according to an embodiment of the invention comprises a device for eliminating boundary layers in a wind tunnel according to any one of the embodiments of the invention in one aspect or a device for eliminating boundary layers in a wind tunnel according to another embodiment of the invention in another aspect.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic representation of a prior art wind tunnel.

Fig. 2 is a schematic cross-sectional view taken along line a-a in fig. 1.

Fig. 3 is an enlarged schematic view of B in fig. 2.

FIG. 4 is a schematic view of a wind tunnel according to an embodiment of the present invention.

Fig. 5 is a schematic cross-sectional view at C-C in fig. 4.

Fig. 6 is an enlarged schematic view of E in fig. 5.

FIG. 7 is a schematic cross-sectional view taken at D-D of FIG. C, showing the two dampers in a fully open position.

FIG. 8 is a schematic sectional view taken at D-D in FIG. C, showing the two dampers in a half-open state.

Reference numerals:

outlet 402 of inlet 401 of bypass air duct 4 of experimental section 3 of contraction section 2 of main fan 1

Bypass airflow 5 and main airflow 6 regulating damper 7

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

An apparatus for eliminating boundary layers in a wind tunnel according to an embodiment of an aspect of the present invention is described below with reference to fig. 4 to 8.

As shown in fig. 4 to 8, according to the device for eliminating the boundary layer in the wind tunnel in the embodiment of the aspect of the present invention, the wind tunnel includes an experimental section 3 and a contraction section 2 which are directly connected, the contraction section 2 is located at the upstream of the experimental section 3, a main fan 1 is arranged in the wind tunnel, the main fan 1 is located at the upstream of the contraction section 2, the device for eliminating the boundary layer in the wind tunnel includes a bypass air duct 4, an inlet 401 of the bypass air duct 4 is communicated with the contraction section 2, an outlet 402 of the bypass air 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 a bypass air flow 5 coming out from the bypass air duct is in the same direction as a.

According to the device for eliminating the boundary layer in the wind tunnel, which is disclosed by the embodiment of the invention, on the one hand, the wind tunnel is an airflow closed loop, when the main fan 1 works, airflow circularly flows in the wind tunnel, and the airflow blown out by the main fan 1 enters the experimental section 3 through the contraction section 2 to provide environmental conditions for the experimental section 3; by arranging the bypass air duct 4, the air flow flowing through the contraction section 2 is divided, one part of the divided air flow is the main air flow 6 for experimental test, the other part of the divided air flow is the bypass air flow 5 blown out from the bottom surface of the experiment section 3 through the bypass air duct 4, the bypass air flow 5 coming out of the bypass air duct is in the same direction as the main air flow 6 coming out of the contraction section 2, the boundary layer of the air flow at the bottom of the experiment section 3 can be effectively eliminated by utilizing the bypass air flow, the quality of the main air flow 6 is not influenced, the technical index of the main air flow 6 can be ensured, and the experimental precision is ensured; meanwhile, extra equipment such as a boundary layer suction device in the prior art is not needed, and the construction cost and the later maintenance cost are reduced. In addition, on one hand, the device for eliminating the boundary layer in the wind tunnel is simple in structure and low in cost.

According to one embodiment of an aspect of the present invention, the inlet 401 of the bypass air duct 4 communicates with the bottom of the convergent section 2. Therefore, the bypass air duct 4 is arranged reasonably.

According to some embodiments of an aspect of the present invention, the device for eliminating boundary layers in a wind tunnel further comprises a damper 7, the damper 7 being disposed at an inlet 401 of the bypass duct 4 to close and open the inlet 401. It can be understood that, by arranging the damper 7 at the inlet 401 of the bypass air duct, the opening degree of the damper 7 can be adjusted according to actual needs, so that the technical index of the main air flow 6 can be ensured without affecting the quality of the main air flow 6 while effectively eliminating the air flow boundary layer at the bottom of the experimental section 3.

According to a further embodiment of an aspect of the present invention, there are two dampers 7, and the two dampers 7 are respectively disposed at opposite sides of the inlet 401 of the side air duct 4. By providing two dampers 7, it is possible to open or close the inlet 401 of the bypass duct 4.

According to a further embodiment of an aspect of the invention, the damper 7 is connected to a control system, which controls the opening of the damper 7. In this way, automatic damper adjustment can be achieved.

According to a further embodiment of one aspect of the present invention, the control system further controls the rotation speed of the main blower 1 to control the bypass airflow 5 to be in seamless joint with the main airflow 6, so as to ensure the technical index of the main airflow 6 and eliminate the boundary layer of the airflow at the bottom of the experimental section 3.

An apparatus for eliminating boundary layers in a wind tunnel according to another aspect of the present invention will be described with reference to fig. 4 to 8.

As shown in fig. 4 to 8, according to another embodiment of the present invention, the device for eliminating the boundary layer in the wind tunnel includes an experimental section 3 and a contraction section 2 which are directly connected, the contraction section 2 is located at the upstream of the experimental section 3, a main fan 1 is disposed in the wind tunnel, the main fan 1 is located at the upstream of the contraction section 2, and the device for eliminating the boundary layer in the wind tunnel includes a bypass air duct 4 and a damper 7, wherein an inlet 401 of the bypass air duct 4 is communicated with the bottom of the contraction section 2, and an outlet 402 of the bypass air duct 4 is communicated with the experimental section 3 and located on the inner surface of the bottom wall of the experimental section 3, so that a bypass air flow 5 coming out from the bypass air duct and a main air flow 6 coming out from the contraction section 2; two damper doors 7 are provided, and the two damper doors 7 are respectively provided at opposite sides of the inlet 401 of the bypass duct 4 to close and open the inlet 401; the two air damper 7 are connected with a control system, the control system controls the opening degree of the air damper 7, and the control system also controls the rotating speed of the main fan 1 so as to control the seamless butt joint of the bypass airflow 5 and the main airflow 6.

According to the device for eliminating the boundary layer in the wind tunnel in the embodiment of the invention on the other hand, the wind tunnel is an airflow closed loop, when the main fan 1 works, airflow circularly flows in the wind tunnel, and the airflow blown out by the main fan 1 enters the experimental section 3 through the contraction section 2 to provide environmental conditions for the experimental section 3; by arranging the bypass air duct 4, the air flow passing through the contraction section 2 is divided, one part of the divided air flow is the main air flow 6 for experimental test, the other part of the divided air flow is that the bypass air flow 5 is blown out from the bottom surface of the experiment section 3 through the bypass air duct 4, the bypass air flow 5 coming out from the bypass air duct and the main air flow 6 coming out from the contraction section 2 are in the same direction, two damper doors 7 are arranged at an inlet 401 of the bypass air duct, the opening of the damper doors 7 is controlled through a specific control system, the rotating speed of a main fan 1 in the air duct is adjusted, the seamless butt joint of regulation and control of the bypass air flow 5 and the main air flow 6 is achieved, the boundary layer of the air flow at the bottom of the experiment section 3 can be effectively eliminated by utilizing the bypass air flow, the quality of the main air flow 6 is not influenced; meanwhile, extra equipment such as a boundary layer suction device in the prior art is not needed, and the construction cost and the later maintenance cost are reduced. In addition, the device for eliminating the boundary layer in the wind tunnel in the embodiment of the invention has simple structure and low cost.

The invention further provides a wind tunnel.

A wind tunnel according to an embodiment of the invention comprises a device for eliminating boundary layers in a wind tunnel according to any one of the embodiments of the invention in one aspect or in another aspect.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims (8)

1. The utility model provides a device on boundary layer is eliminated in wind-tunnel, the wind-tunnel includes direct consecutive experiment section and shrink section, the shrink section is located experiment section upper reaches, be provided with main fan in the wind-tunnel, main fan is located shrink section upper reaches, its characterized in that, the device on boundary layer includes in the wind-tunnel:

and the inlet of the bypass air channel is communicated with the contraction section, and the outlet of the bypass air channel is communicated with the experiment section and is positioned on the inner surface of the bottom wall of the experiment section, so that bypass airflow coming out of the bypass air channel and main airflow coming out of the contraction section are in the same direction. The technical index of the main air flow is ensured, the quality of the main air flow is not influenced, and the air flow boundary layer at the bottom of the experimental section is eliminated.

2. The boundary layer elimination apparatus of claim 1 wherein the inlet of said bypass duct communicates with the bottom of said convergent section.

3. The boundary layer elimination apparatus in a wind tunnel according to claim 1 or 2, wherein said boundary layer elimination apparatus in a wind tunnel further comprises a damper disposed at said inlet of said bypass duct to close and open said inlet.

4. The boundary layer elimination apparatus of claim 3 wherein said two dampers are disposed on opposite sides of said inlet of said bypass duct.

5. The boundary layer elimination apparatus of claim 3 wherein said damper is connected to a control system, said control system controlling the opening of said damper.

6. The boundary layer elimination apparatus of claim 5, wherein said control system further controls said main fan speed to control said bypass air flow to seamlessly interface with said main air flow.

7. The utility model provides a device on boundary layer is eliminated in wind-tunnel, the wind-tunnel includes direct consecutive experiment section and shrink section, the shrink section is located experiment section upper reaches, be provided with main fan in the wind-tunnel, main fan is located shrink section upper reaches, its characterized in that, the device on boundary layer includes in the wind-tunnel:

the inlet of the bypass air channel is communicated with the bottom of the contraction section, and the outlet of the bypass air channel is communicated with the experiment section and is positioned on the inner surface of the bottom wall of the experiment section, so that bypass airflow coming out of the bypass air channel and main airflow coming out of the contraction section are in the same direction;

the two air adjusting doors are respectively arranged on two opposite sides of the inlet of the bypass air channel so as to close and open the inlet; the two air adjusting doors are connected with a control system, the control system controls the opening degree of the air adjusting doors, and the control system also controls the rotating speed of the main fan so as to control the seamless butt joint of the bypass airflow and the main airflow.

8. A wind tunnel comprising an apparatus for boundary layer elimination in a wind tunnel according to any one of claims 1 to 6 or an apparatus for boundary layer elimination in a wind tunnel according to claim 7.

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