A protective device for supersonic wind tunnel flow calibration pressure measuring hose

Abstract

The present invention discloses a protective device for a supersonic wind tunnel flow calibration pressure measuring hose. Along the wind tunnel airflow direction, the protective device is located behind the scimitar bracket of the wind tunnel test section, and includes an inner layer protective mechanism and an outer layer protective mechanism, wherein the inner layer protective mechanism is placed as a whole in the outer layer protective mechanism; the outer layer protective mechanism is composed of a rear protective cover, a mounting base, a front protective cover and a cover plate, and has a connected chamber inside to accommodate the inner layer protective mechanism. After the pressure measuring hoses led out from the cross pressure measuring rack are bundled, they pass through the protective device, enter the wind tunnel resident chamber and are connected to the wind tunnel pressure measuring system. The protective device uses a metal bellows to protect the pressure measuring hose, which moves back and forth with the lead screw and works together with the outer layer protective mechanism to avoid the influence and damage of the supersonic airflow on the pressure measuring hose, effectively protect the pressure measuring hose of the flow calibration mechanism, solve the wiring problem of multiple pressure measuring tubes in the flow channel of the supersonic wind tunnel, and ensure the reliable acquisition of the pressure measurement data of the supersonic wind tunnel test.

Description

Technical Field

[0001] The invention belongs to the technical field of wind tunnel tests, and in particular relates to a protective device for a supersonic wind tunnel flow calibration and pressure measuring hose. Background Art

[0002] During the supersonic wind tunnel flow field calibration, a transfer and measurement mechanism is used to measure the pressure distribution of the test section. The transfer and measurement mechanism consists of a servo motor, a transverse transmission shaft, a bevel gear pair, and a lead screw nut pair, which converts the rotational motion of the motor into the forward and backward motion of the lead screw. During the test, the transfer and measurement mechanism adopts the zero-position start and shutdown operation mode. When the supersonic wind tunnel successfully establishes the supersonic flow field, the transfer and measurement mechanism runs to the front position and then retreats in steps to measure the pressure distribution at each given position. The lead screw of the transfer and measurement mechanism is a hollow structure. The pressure measuring tube passes through the lead screw and is connected to the scanning valve installed in the resident chamber to measure the probe pressure. The pressure measuring tube cannot withstand the aerodynamic load during the supersonic wind tunnel blowing. During the supersonic wind tunnel blowing, the pressure measuring tube swings with the wind, which will cause damage to the pressure measuring tube.

[0003] In order to solve the problem that the pressure measuring tube of the moving measuring mechanism is directly exposed to the flow channel in the wind tunnel after passing through the screw during the supersonic wind tunnel blowing process, it is necessary to develop a special supersonic wind tunnel flow calibration pressure measuring hose protection device. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a supersonic wind tunnel flow calibration pressure measuring hose protection device.

[0005] The supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention is characterized in that, along the wind tunnel airflow direction, the pressure measuring hose protection device is located behind the scimitar bracket of the wind tunnel test section, and includes an inner layer protection mechanism and an outer layer protection mechanism, and the inner layer protection mechanism is placed in the outer layer protection mechanism as a whole; the inner layer protection mechanism is composed of a hollow adapter and a metal bellows, the front end of the hollow adapter is connected to the hollow screw of the transfer and measurement mechanism, and the rear end of the hollow adapter is connected to the metal bellows; the outer layer protection mechanism is composed of a rear protective cover, a mounting base, a front protective cover and a cover plate, the lower part of the mounting base is fixed to the inner shell of the wind tunnel resident room by connecting screws, and the upper part of the mounting base is fixed with a cover plate, a front protective cover and a rear protective cover in sequence from front to back; the cover plate has two pieces, It is symmetrically installed on the left and right sides of the mounting base by connecting countersunk screws; the front protective cover is U-shaped; the rear protective cover is also U-shaped, and the rear protective cover covers the hollow screw, hollow adapter and metal bellows, and the length of the rear protective cover is greater than the front and rear moving distance of the hollow screw, hollow adapter and metal bellows; the front protective cover and the rear protective cover are fixed to the mounting base by their respective connecting bolt groups; after the rear protective cover, the front protective cover, the cover plate and the mounting base are fixedly installed, there is a connected chamber inside to accommodate the hollow screw, the hollow adapter, the metal bellows and the pressure measuring hose, and the pressure measuring hose led out from the cross pressure measuring rack is bundled, passed through the hollow screw, the hollow adapter and the metal bellows, enters the wind tunnel resident room and is connected to the wind tunnel pressure measuring system.

[0006] The tube body of the metal bellows is a metal braided bellows, and both ends of the metal bellows are provided with movable connecting nuts.

[0007] The rear protective cover is fixed with a guide bolt group, which is divided into a front guide bolt group and a rear guide bolt group. The front guide bolt group is composed of a series of bolts arranged upward from the front to the rear arc near the wind tunnel scimitar, and the rear guide bolt group is composed of a series of bolts arranged upward from the front to the rear arc near the rear end of the rear protective cover; the height of the tail bolt of the front guide bolt group is higher than the head bolt of the rear guide bolt group, and lower than the tail bolt of the rear guide bolt group.

[0008] The rear protective cover is provided with air pressure balance holes symmetrically arranged on the left and right sides.

[0009] The projection of the outer layer protection mechanism in the direction of airflow is located in the projection of the scimitar bracket of the wind tunnel test section in the direction of airflow, and the projection area is smaller than the projection area of ​​the scimitar bracket of the wind tunnel test section in the direction of airflow.

[0010] The metal bellows in the supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention has both flexibility and certain strength. The flexibility can meet the need to move together with the hollow screw, and the strength can resist the impact of supersonic airflow on the pressure measuring hose inside the metal bellows.

[0011] The pressure measuring hose in the supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention is routed through the hollow screw, the metal bellows and the chamber, and does not directly contact the supersonic airflow in the flow channel of the wind tunnel.

[0012] The guide bolt group in the supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention ensures that the movement trajectory of the metal bellows wrapping the pressure measuring hose in the chamber is controlled.

[0013] The symmetrical air pressure balance holes on the left and right sides of the rear protective cover in the supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention ensure that the air pressure in the chamber is the same as the flow channel pressure in the wind tunnel.

[0014] The projection of the outer layer protection mechanism in the supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention in the direction of airflow is located in the projection of the scimitar bracket of the wind tunnel test section, and the projection area is smaller than the projection area of ​​the scimitar bracket of the wind tunnel test section, that is, the supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention does not increase the blockage of the flow calibration device. At the same time, the adjustable wall panel of the supersonic wind tunnel super expansion section can still be rotated and adjusted by rotating the hinge according to the requirements of the wind tunnel working conditions, that is, the supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention will not produce structural interference with the movement of the adjustable wall panel of the super expansion section of the wind tunnel, and can meet the pressure measurement requirements of all Mach numbers of supersonic wind tunnel flow calibration.

[0015] The supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention adopts a metal bellows to protect the pressure measuring hose. The metal bellows moves back and forth with the screw and works together with the outer protection mechanism to avoid the influence and damage of the supersonic airflow on the pressure measuring hose, effectively protect the pressure measuring hose of the flow calibration mechanism, solve the problem of routing multiple pressure measuring tubes in the flow channel of the supersonic wind tunnel, and ensure the reliable acquisition of supersonic wind tunnel test pressure measurement data.

[0016] The supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention has a simple structure, reliable function, and convenient installation, and can meet the pressure measurement requirements of all Mach numbers of supersonic wind tunnel flow calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention;

[0018] Figure 2 yes Figure 1 AA section view;

[0019] Figure 3 yes Figure 2 A partial enlarged view of I;

[0020] Figure 4 yes Figure 1 BB cross-sectional view (removing the front and rear protective covers);

[0021] Figure 5 yes Figure 1 CC cross-sectional view (excluding the transfer and measurement mechanism and pressure measuring hose);

[0022] Figure 6 yes Figure 4 DD cross-sectional view;

[0023] Figure 7 yes Figure 4 Enlarged view of the EE cross section.

[0024] In the figure, 1. Cross pressure test rack 2. Wind tunnel test section machete bracket 3. Moving test mechanism 4. Rear protective cover 5. Guide bolt group 6. Hollow rotating joint 7. Metal bellows 8. Connecting bolt group 9. Mounting base 10. Connecting screw 11. Front protective cover 12. Connecting countersunk screw 13. Cover plate 14. Pressure test hose 15. Rotating hinge 16. Adjustable wall plate 17. Wind tunnel indoor shell 18. Air pressure balance hole;

[0025] 301. Servo motor 302. Transverse transmission shaft 303. Driving bevel gear 304. Driven bevel gear 305. Hollow screw 306. Guide key 307. Middle bracket. DETAILED DESCRIPTION

[0026] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0027] Example 1

[0028] like Figure 1 , 4 As shown, in this embodiment, the supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention is applied to a supersonic wind tunnel flow calibration device. The flow calibration device is composed of a cross pressure measuring rack 1 and a moving and measuring mechanism 3. The cross pressure measuring rack 1 is fixed on the scimitar bracket 2 of the wind tunnel test section through the middle bracket 307 on the moving and measuring mechanism 3; the moving and measuring mechanism 3 drives the transverse transmission shaft 302 to rotate through the servo motor 301, and the transverse transmission shaft 302 is connected to the active bevel gear 303, and the active bevel gear 303 drives the driven bevel gear 304 to rotate. The driven bevel gear 304 is an outer bevel gear with an internal hollow thread structure. The internal hollow thread of the driven bevel gear 304 and the hollow lead screw 305 form a lead screw nut pair, and the hollow lead screw 305 is driven to make forward and backward linear motion through the guide key 306 fixed on the middle bracket 307.

[0029] like Figure 1 , 2As shown in Figures 3, 5, 6 and 7, along the airflow direction of the wind tunnel, the supersonic wind tunnel flow calibration and pressure measuring hose protection device of the present invention is located behind the scimitar bracket 2 of the wind tunnel test section, and includes an inner protection mechanism and an outer protection mechanism, and the inner protection mechanism is placed as a whole in the outer protection mechanism; the inner protection mechanism is composed of a hollow adapter 6 and a metal bellows 7, the front end of the hollow adapter 6 is connected to the hollow screw 305 of the transfer and measurement mechanism 3, and the rear end of the hollow adapter 6 is connected to the metal bellows 7; the outer protection mechanism is composed of a rear protective cover 4, a mounting base 9, a front protective cover 11 and a cover plate 13, the lower part of the mounting base 9 is fixed to the wind tunnel indoor shell 17 by connecting screws 10, and the upper part of the mounting base 9 is fixed with a cover plate 13, a front protective cover 11 and a rear protective cover 4 in sequence from front to back; the cover plate 13 has two pieces, which are connected by countersunk screws 12 It is installed on the left and right sides of the mounting base 9; the front protective cover 11 is U-shaped; the rear protective cover 4 is also U-shaped, and the rear protective cover 4 covers the hollow screw 305, the hollow adapter 6 and the metal bellows 7, and the length of the rear protective cover 4 is greater than the front and rear moving distance of the hollow screw 305, the hollow adapter 6 and the metal bellows 7; the front protective cover 11 and the rear protective cover 4 are fixed to the mounting base 9 by their respective connecting bolt groups 8; after the rear protective cover 4, the front protective cover 11, the cover plate 13 and the mounting base 9 are fixedly installed, there is a connected chamber inside to accommodate the hollow screw 305, the hollow adapter 6, the metal bellows 7 and the pressure measuring hose 14, and the pressure measuring hose 14 led out from the cross pressure measuring rack 1 is bundled, passes through the hollow screw 305, the hollow adapter 6 and the metal bellows 7, enters the wind tunnel resident room and is connected to the wind tunnel pressure measuring system.

[0030] The tube body of the metal bellows 7 is a metal braided bellows, and both ends of the metal bellows 7 are provided with movable connecting nuts.

[0031] The rear protective cover 4 is fixed with a guide bolt group 5, which is divided into a front guide bolt group and a rear guide bolt group. The front guide bolt group is composed of a series of bolts arranged upward in an arc from front to rear near the wind tunnel scimitar, and the rear guide bolt group is composed of a series of bolts arranged upward in an arc from front to rear near the rear end of the rear protective cover 4; the height of the tail bolt of the front guide bolt group is higher than the head bolt of the rear guide bolt group, and lower than the tail bolt of the rear guide bolt group.

[0032] The rear protective cover 4 is provided with air pressure balance holes 18 symmetrically disposed on the left and right sides.

[0033] The projection of the outer layer protection mechanism in the airflow direction is located in the projection of the scimitar bracket 2 of the wind tunnel test section in the airflow direction of the wind tunnel, and the projection area is smaller than the projection area of ​​the scimitar bracket 2 of the wind tunnel test section in the airflow direction.

[0034] like Figure 1As shown, during the supersonic wind tunnel flow calibration process, since the supersonic wind tunnel flow calibration pressure measuring hose protection device of the present invention is located in the groove of the adjustable wall panel 16 of the super-expansion section of the supersonic wind tunnel, there is a gap between the adjustable wall panel 16, so that the adjustable wall panel 16 can still be rotated and adjusted by rotating the hinge 15 according to the requirements of the wind tunnel working conditions, and no structural interference will be generated to the movement of the adjustable wall panel 16.

Claims

1. A supersonic wind tunnel flow calibration pressure measuring hose protection device, characterized in that: Along the wind tunnel airflow direction, the pressure measuring hose protection device is located behind the curved knife bracket (2) of the wind tunnel test section, and includes an inner layer protection mechanism and an outer layer protection mechanism, wherein the inner layer protection mechanism is placed as a whole in the outer layer protection mechanism; the inner layer protection mechanism is composed of a hollow adapter (6) and a metal bellows (7), the front end of the hollow adapter (6) is connected to the hollow screw (305) of the moving and measuring mechanism (3), and the rear end of the hollow adapter (6) is connected to the metal bellows (7); the outer layer protection mechanism is composed of a rear protection cover (4), a mounting base (9), a front protection cover (11) and a cover plate (13), the lower part of the mounting base (9) is fixed to the wind tunnel indoor shell (17) by connecting screws (10), and the upper part of the mounting base (9) is fixed with a cover plate (13), a front protection cover (11) and a rear protection cover (4) in sequence from front to back; the cover plate (13) has two pieces, which are symmetrically installed on the left and right sides of the mounting base (9) by connecting countersunk screws (12). The front protective cover (11) is U-shaped; the rear protective cover (4) is also U-shaped, and the rear protective cover (4) covers the hollow screw (305), the hollow transfer joint (6) and the metal bellows (7), and the length of the rear protective cover (4) is greater than the front-to-back movement distance of the hollow screw (305), the hollow transfer joint (6) and the metal bellows (7); the front protective cover (11) and the rear protective cover (4) are both fixed to the mounting base (9) by their respective connecting bolt groups (8); the rear protective cover After the cover (4), the front protective cover (11), the cover plate (13) and the mounting base (9) are fixedly installed, a connected chamber is provided inside to accommodate the hollow screw (305), the hollow adapter (6), the metal bellows (7) and the pressure measuring hose (14). The pressure measuring hose (14) led out from the cross pressure measuring rack (1) is bundled, passes through the hollow screw (305), the hollow adapter (6) and the metal bellows (7), enters the wind tunnel station room and is connected to the wind tunnel pressure measuring system.

2. The supersonic wind tunnel flow calibration pressure measuring hose protection device according to claim 1 is characterized in that: The tube body of the metal bellows (7) is a metal braided bellows, and both ends of the metal bellows (7) are provided with movable connection nuts.

3. The supersonic wind tunnel flow calibration pressure measuring hose protection device according to claim 1 is characterized in that: The rear protective cover (4) is fixed with a guide bolt group (5), which is divided into a front guide bolt group and a rear guide bolt group. The front guide bolt group is composed of a series of bolts arranged upward from the front to the rear arc near the wind tunnel scimitar, and the rear guide bolt group is composed of a series of bolts arranged upward from the front to the rear arc near the rear end of the rear protective cover (4); the height of the tail bolt of the front guide bolt group is higher than the head bolt of the rear guide bolt group, and lower than the tail bolt of the rear guide bolt group.

4. The supersonic wind tunnel flow calibration pressure measuring hose protection device according to claim 1 is characterized in that: The rear protective cover (4) is provided with air pressure balance holes (18) symmetrically arranged on the left and right sides.

5. The supersonic wind tunnel flow calibration pressure measuring hose protection device according to claim 1, characterized in that: The projection of the outer layer protection mechanism in the airflow direction is located in the projection of the wind tunnel test section scimitar bracket (2) in the airflow direction of the wind tunnel, and the projection area is smaller than the projection area of ​​the wind tunnel test section scimitar bracket (2) in the airflow direction.

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