A wind tunnel turbojet engine model balance and elastic angle calibration method

Abstract

A wind tunnel turbojet engine model balance and elastic angle calibration method belong to the technical field of wind tunnel balance design and calibration. The present invention solves the problem that the large-scale balance required for the large-scale surface model in the wind tunnel test section does not have a suitable conventional support rod and loading head for elastic angle calibration. The wind tunnel balance of the present invention is connected to the upper wall plate of the wind tunnel through the balance rear bracket and the balance front bracket, the balance rear bracket and the balance front bracket are connected through a reinforcement rod, the pulley adapter is installed on the wind tunnel upper wall plate, the pulley is connected to the wind tunnel upper wall plate through the pulley adapter, the front end of the wind tunnel balance is connected to the projectile body, the steel belt bypasses the projectile body and is clamped and closed into a loop through a clamping block, the other end of the steel belt bypasses the pulley and is connected to the hanging rod, the hanging rod is connected to the weight plate, and a weight string is arranged on the weight plate. A wind tunnel turbojet engine model balance and elastic angle calibration method of the present invention solves the problems of balance design, measurement and calibration of large-scale models.

Description

Technical Field

[0001] The invention belongs to the technical field of wind tunnel balance design and calibration, and in particular relates to a wind tunnel turbojet engine model balance and an elastic angle calibration method. Background Art

[0002] As the size of wind tunnel test sections continues to increase, there is an increasing demand for large-scale models with a ratio of 1:1. The demand is greater for airborne equipment, such as engines, to be tested in wind tunnels. Large-scale models mean greater aerodynamic loads and higher balance stiffness requirements. At the same time, due to the existence of the engine's thrust vector, the ratio of the balance torque and force is much greater than the load ratio of a conventional balance. For example, the patent announcement number is CN118032260B, and the patent name is "A forward-matching wind tunnel test support and attitude adjustment device". In this patent, large-scale models require longer and thicker large-scale balances to ensure the matching of each element output and the stiffness of the balance. The large balance also means that there are no suitable conventional support rods and loading heads for elastic angle calibration.

[0003] Therefore, the present application proposes a wind tunnel turbojet engine model balance and elastic angle calibration method to solve the above problems. Summary of the invention

[0004] The purpose of the present invention is to solve the problem that the large-scale balance required for the large-scale surface model in the wind tunnel test section does not have a conventional support rod and loading head that can be adapted for elastic angle calibration. A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to identify the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0005] The technical solution of the present invention:

[0006] Solution 1: A wind tunnel turbojet engine model balance, including a wind tunnel balance, a balance rear bracket, a balance front bracket, a pulley adapter, a pulley, a weight plate, a weight string and a projectile body. The wind tunnel balance is connected to the upper wall plate of the wind tunnel through the balance rear bracket and the balance front bracket, the balance rear bracket and the balance front bracket are connected through a reinforcement rod, the pulley adapter is installed on the wind tunnel upper wall plate, the pulley is connected to the wind tunnel upper wall plate through the pulley adapter, the rear end of the wind tunnel balance is connected to the balance rear bracket, the front end of the wind tunnel balance is connected to the projectile body, the projectile body is arranged outside the reinforcement rod, one end of the steel belt passes around the projectile body and is clamped and closed into a loop through a clamping block, the other end of the steel belt passes around the pulley and is connected to the hanging rod, the hanging rod is connected to the weight plate, and the weight plate is provided with a weight string.

[0007] Furthermore, an extended fixing block and a fixing plate are provided above the upper wall plate of the wind tunnel, the extended fixing block is connected to the fixing plate, a connecting rod is installed at the bottom of the extended fixing block, the connecting rod passes through the upper wall plate of the wind tunnel and is arranged in the wind tunnel, the rear bracket of the balance and the front bracket of the balance are installed on the connecting rod, screws pass through the upper wall plate of the wind tunnel to connect the pulley adapter and the fixing plate, the bottom of the pulley adapter is connected to a universal support, and the pulley is rotatably installed on the universal support.

[0008] Furthermore, the rear end of the wind tunnel balance is connected to the rear bracket of the balance via an end face key, and the front end of the wind tunnel balance is connected to the body via an end face key.

[0009] Furthermore, a first protective cover and a second protective cover are provided at the front end of the wind tunnel balance, and the first protective cover and the second protective cover are connected to form a sleeve mounted on the wind tunnel balance.

[0010] Furthermore, the first protective cover and the second protective cover are made of aluminum material, and the diameter of the wind tunnel balance is 100 mm.

[0011] Furthermore, the interface between the universal support and the pulley adapter has a gap in the lift direction, the gap height is 1 mm, and multiple extended pads are arranged between the pulley adapter and the extended fixing block. Screws pass through the upper wall panel of the wind tunnel and the extended pads to connect the pulley adapter to the extended fixing block.

[0012] Solution 2: A method for calibrating the elastic angle of a wind tunnel turbojet engine model balance, which is based on the wind tunnel turbojet engine model balance described in Solution 1 and includes the following steps:

[0013] Step 1: After leveling the reference plane of the connecting rod, install it on the extended fixing block at the bottom of the upper wall plate of the wind tunnel. The rear bracket of the balance is mounted on the connecting rod and fixed by screws and pins. The rear bracket of the balance and the rear end of the wind tunnel balance are connected by end face keys. The wind tunnel balance does not adjust the γ angle.

[0014] Step 2: Connect the balance rear bracket and four reinforcement rods by screws, connect the spring body to the front end of the wind tunnel balance by end face keys after passing through the four reinforcement rods, and put the balance front bracket on the connecting rod and fix it by screws and pins. The balance front bracket, balance rear bracket and four reinforcement rods form a fixed end to ensure the rigidity of the wind tunnel balance fixed end;

[0015] Step 3: Connect the pulley adapter through the wind tunnel upper wall plate and the fixed plate by screws, and connect the pulley adapter through the wind tunnel upper wall plate and the extended pad plate and the extended fixed block by screws;

[0016] Step 4: The universal support is two symmetrical plates, which are respectively embedded in the interfaces on both sides of the pulley adapter. Under the action of gravity, the universal support and the lower boundary limit contact of the universal support interface, tighten the screws to fix the universal support and the pulley adapter. When the universal support and the pulley adapter are connected, the two symmetrical plates of the universal support are connected by screws to rotate the pulley;

[0017] Step 5: Clamp one end of the steel belt into a loop through a clamping block and put it on the elastic body. The other end of the steel belt passes through the pulley and is connected to the hanging rod, and the hanging rod is connected to the weight plate;

[0018] Step 6: Measure the distance between the center of the steel belt and the front end of the balance rear bracket. , place a weight of The weight string is used to measure the deformation difference of the projectile body position corresponding to the center of the steel belt relative to the side wall of the wind tunnel under the influence of the weight string. ;

[0019] Step 7: Set the yaw spring coefficient related to the wind tunnel balance side force to , the yaw elastic angular coefficient related to the yaw moment is , is the yaw angle caused by the load condition, and the corresponding formula is as follows:

[0020] (1);

[0021] in and is the coefficient to be determined, g is the local gravitational acceleration, and is the lateral force and yaw moment generated by the weight;

[0022] Step 8: Move the pulley adapter along the axial direction of the model, and the steel belt moves accordingly. The distance between the center of the steel belt and the front end of the rear bracket of the balance is measured to be , place a weight of The weight string is used to measure the deformation difference of the projectile body position corresponding to the center of the steel belt relative to the side wall of the wind tunnel under the influence of the weight string. ;

[0023] Step 9: Settings The yaw angle caused by this load condition has the following corresponding formula:

[0024] (2);

[0025] in and is the coefficient to be determined, and is the lateral force and yaw moment generated by the weight;

[0026] Step 10: Combine formula (1) and formula (2) to obtain the elastic angle coefficient corresponding to the measured force and yaw moment and ;

[0027] Step 11: Remove the steel belt from the pulley, connect the steel belt directly to the weight plate and the weight string through the hanging rod, and apply lift and pitch moment to the model under the action of gravity to obtain the elastic angular coefficient corresponding to the lift and pitch moment. and , the corresponding formula is as follows:

[0028] (3);

[0029] (4);

[0030] in , is the lift force generated by the weight, , is the yaw moment generated by the weight, is the angle of attack produced by the weight;

[0031] Each time loading is performed, the weights of different masses are applied and the average value is taken, that is, , is the average value of multiple application of weights, , The average of the yaw and pitch angles produced by applying weights multiple times improves the accuracy of elastic angle measurement.

[0032] The present invention has the following beneficial effects:

[0033] A wind tunnel turbojet engine model balance of the present invention adopts a large-diameter balance to ensure the coordination of force and torque output. Test results show that the accuracy of the balance can reach the advanced indicators of the wind tunnel strain balance specification GJB2244A-2011.

[0034] A wind tunnel turbojet engine model balance of the present invention effectively improves the rigidity of the fixed end and reduces the deformation of the model through the front and rear brackets of the balance and four reinforcement rods.

[0035] The invention discloses an elastic angle calibration method for a wind tunnel turbojet engine model balance, which realizes an elastic angle calibration method for a large-size model in a limited wind tunnel space. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the overall structure of a wind tunnel turbojet engine model balance;

[0037] Figure 2 This is a schematic diagram of the force measurement part of the wind tunnel balance;

[0038] Figure 3 yes Figure 2 Middle AA section view;

[0039] Figure 4 is a schematic diagram of the elastic angle calibration part;

[0040] Figure 5 It is a top view of a wind tunnel turbojet engine model balance;

[0041] Figure 6 It is a schematic diagram of the matching relationship between the extended fixing block and the fixing plate.

[0042] In the figure: 1-wind tunnel balance, 2-balance rear bracket, 3-balance front bracket, 4-left protective cover, 5-right protective cover, 6-end key, 7-reinforcement rod, 8-connecting rod, 9-pulley adapter, 10-extension pad, 11-extension fixing block, 12-fixing plate, 13-universal support, 14-pulley, 15-steel belt, 16-clamping block, 17-hanging rod, 18-weight plate, 19-weight string, 20-elastic body, 21-wind tunnel upper wall plate. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0044] The connection mentioned in the present invention is divided into fixed connection and detachable connection. The fixed connection (i.e., non-detachable connection) includes but is not limited to conventional fixed connection methods such as folding connection, rivet connection, bonding connection and welding connection. The detachable connection includes but is not limited to conventional detachable methods such as threaded connection, snap connection, pin connection and hinge connection. When the specific connection method is not clearly defined, it is assumed that at least one connection method can always be found in the existing connection methods to achieve the function. Those skilled in the art can choose according to their needs. For example: welding connection is selected for fixed connection, and hinge connection is selected for detachable connection.

[0045] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] Embodiment 1, combination Figure 1-Figure 6 The present embodiment is described. A wind tunnel turbojet engine model balance of the present embodiment comprises a wind tunnel balance 1, a balance rear bracket 2, a balance front bracket 3, a pulley adapter 9, a pulley 14, a weight plate 18, a weight string 19 and a projectile 20. The wind tunnel balance 1 is connected to the wind tunnel upper wall plate 21 through the balance rear bracket 2 and the balance front bracket 3. The balance rear bracket 2 and the balance front bracket 3 are connected through a reinforcing rod 7. The pulley adapter 9 is installed on the wind tunnel upper wall plate 21. The pulley 14 is connected to the wind tunnel upper wall plate 21 through the pulley adapter 9. The projectile 20 is connected between the balance rear bracket 2 and the balance front bracket 3. The steel belt 15 passes around the projectile 20 and is clamped and closed into a loop through a clamping block 16. The other end of the steel belt 15 passes around the pulley 14 and is connected to a hanging rod 17. The hanging rod 17 is connected to the weight plate 18. A weight string 19 is provided on the weight plate 18.

[0047] In this embodiment, the space of the loading device is approximately 2400mm (x direction) × 880mm (z direction) × 1600mm (y direction), which is mainly related to the size of the wind tunnel and the model. The lift and side force can be loaded with 1000N. To meet the large torque of the 1:1 scale turbojet engine model, the wind tunnel balance 1 is designed to have a diameter of 100mm to ensure the coordination of the normal and lateral torque components and force component outputs. At the same time, the balance is designed in a four-column beam form to improve the output of the rolling moment;

[0048] The wind tunnel balance 1, the body 20 and the rear bracket 2 of the balance are connected by a flange, and the flange is fixed by 10 M12 screws and two end keys 6 to prevent relative rotation between the wind tunnel balance 1 and the model due to rolling torque. In order to improve the rigidity of the force measuring structure, after the rear end of the wind tunnel balance 1 is connected to the rear bracket 2 of the balance, the rear bracket 2 of the balance is connected to the front bracket 3 of the balance by four reinforcing rods 7, which can effectively improve the rigidity of the fixed end and reduce the displacement of the structure after being subjected to force. One end of the steel belt 15 is sleeved on the body 20 and clamped into a ring by the clamping block 16. The other end of the steel belt 15 passes around the pulley 14 and is threadedly connected to the hanging rod 17. The hanging rod 17 is connected with a weight disk 18, and a weight string 19 is placed on the weight disk 18.

[0049] The pulley adapter 9 passes through the wind tunnel upper wall plate 21 through screws to establish connections with the extended fixing block 11 and the fixing plate 12. The bottom of the pulley adapter 9 is connected to the universal support 13 through an interface and screws. The pulley 14 is rotatably mounted on the universal support 13 through a bearing. Rolling bearings (GB / T276-94 new code 16002 / old code 7000102) are selected for pulley bearings to minimize friction while meeting strength requirements.

[0050] The left protective cover 4 and the right protective cover 5 are connected to the model end of the front end of the wind tunnel balance 1. The left protective cover 4 and the right protective cover 5 are connected to form a cylindrical protective cover which is sleeved on the front end of the wind tunnel balance 1 to protect against wind. The left protective cover 4 and the right protective cover 5 are made of aluminum material. The gravity of the protective cover is much smaller than the balance range and does not affect the balance force measurement.

[0051] In order to realize the lateral elastic angle calibration of different positions of the projectile body in the limited space of the wind tunnel, the pulley 14 structure is designed. Limited by the specific wind tunnel structure, the pulley adapter 9 is provided with two rows of interfaces, one row is screw holes, which are fixed to the wind tunnel upper wall plate 21 with the fixing plate 12 by screws, and the other row is through holes, which are fixed to the wind tunnel upper wall plate 21 by screws through the pulley adapter 9 and the extended fixing block 11. The pulley adapter 9 is provided with a row of threads inserted into the grid of the wind tunnel upper wall plate 21, which has the function of lateral limiting and bearing part of the torque;

[0052] The pulley adapter 9 is provided with a row of interfaces with through holes, and the screw holes connected with the wind tunnel upper wall plate 21 have a screw arrangement sequence limited by the specific structure of the wind tunnel, that is, the distance of its axial movement is a discrete fixed interval rather than a continuous value. When the pulley adapter 9 has a gap with the wind tunnel upper wall plate 21 due to axial movement, the extended pad 10 can play the role of a pad to ensure that the displacement of the pulley adapter 9 in the lift direction remains unchanged;

[0053] The interface between the universal support 13 and the pulley adapter 9 has a 1mm gap in the lift direction and no gap in the lateral force direction, which facilitates installation. Due to the effect of gravity, the upper boundary contact between the universal support 13 and the pulley adapter 9 interface can still be ensured, and the limit in the lift direction can still be ensured. At the same time, the interface can play a supporting role, reduce the force on the interface screws, and improve the structural safety.

[0054] Embodiment 2, combined Figure 1-Figure 6 This embodiment is described. A method for calibrating the elastic angle of a wind tunnel turbojet engine model balance in this embodiment comprises the following steps:

[0055] Step 1: After the reference plane of the connecting rod 8 is leveled, it is installed on the extended fixing block 11 at the bottom of the wind tunnel upper wall plate 21. The balance rear bracket 2 is sleeved on the connecting rod 8 and fixed by screws and pins. The balance rear bracket 2 and the rear end of the wind tunnel balance 1 are connected by the end face key 6. The wind tunnel balance 1 does not adjust the γ angle;

[0056] Step 2: Connect the balance rear bracket 2 and the four reinforcement rods 7 by screws, and the elastic body 20 passes through the four reinforcement rods 7 and is connected to the front end of the wind tunnel balance 1 by the end face key 6, and the balance front bracket 3 is sleeved on the connecting rod 8 and fixed by screws and pins. The balance front bracket 3, the balance rear bracket 2 and the four reinforcement rods 7 form a fixed end to ensure the rigidity of the fixed end of the wind tunnel balance 1;

[0057] Step 3: Connect the pulley adapter 9 through the wind tunnel upper wall plate 21 and the fixing plate 12 by screws, and connect the pulley adapter 9 through the wind tunnel upper wall plate 21 and the extension pad 10 to the extension fixing block 11 by screws;

[0058] Step 4: The universal support 13 is two symmetrical flat plates, which are respectively embedded in the interfaces on both sides of the pulley adapter 9. Under the action of gravity, the universal support 13 and the lower boundary limit contact of the interface of the universal support 13 are tightened to fix the universal support 13 and the pulley adapter 9. When the universal support 13 and the pulley adapter 9 are connected, the two symmetrical flat plates of the universal support 13 are connected by screws to rotate the pulley 14;

[0059] Step 5: One end of the steel belt 15 is clamped into a loop through the clamping block 16 and is put on the elastic body 20, and the other end of the steel belt 15 is passed through the pulley 14 and connected to the hanging rod 17, and the hanging rod 17 is connected to the weight plate 18;

[0060] Step 6: Measure the distance between the center of the steel belt 15 and the front end of the balance rear bracket 2. , place a mass of The weight string 19 is used to measure the deformation difference of the body 20 corresponding to the center of the steel belt 15 relative to the side wall of the wind tunnel under the influence of the weight string 19. ;

[0061] Step 7: Set the yaw elastic angular coefficient related to the side force of wind tunnel balance 1 to , the yaw elastic angular coefficient related to the yaw moment is , is the yaw angle caused by the load condition, and the corresponding formula is as follows:

[0062] (1);

[0063] in and is the coefficient to be determined, g is the local gravitational acceleration, and is the lateral force and yaw moment generated by the weight;

[0064] Step 8: Move the pulley adapter 9 along the axial direction of the model, and the steel belt 15 moves accordingly. The distance between the center of the steel belt 15 and the front end surface of the balance rear bracket 2 is measured to be , place a mass of The weight string 19 is used to measure the deformation difference of the body 20 corresponding to the center of the steel belt 15 relative to the side wall of the wind tunnel under the influence of the weight string 19. ;

[0065] Step 9: Settings The yaw angle caused by this load condition has the following corresponding formula:

[0066] (2);

[0067] in and is the coefficient to be determined, and is the lateral force and yaw moment produced by the weight;

[0068] Step 10: Combine formula (1) and formula (2) to obtain the elastic angle coefficient corresponding to the measured force and yaw moment and ;

[0069] Step 11: Remove the steel belt 15 from the pulley 14, and connect the steel belt 15 directly to the weight plate 18 and the weight string 19 through the hanging rod 17. Under the action of gravity, lift and pitch moment are applied to the model to obtain the elastic angular coefficient corresponding to the lift and pitch moment. and , the corresponding formula is as follows:

[0070] (3);

[0071] (4);

[0072] in , is the lift force generated by the weight, , is the yaw moment generated by the weight, is the angle of attack produced by the weight;

[0073] Each time loading is performed, the weights of different masses are applied and the average value is taken, that is, , is the average value of multiple application of weights, , The average of the yaw and pitch angles produced by applying weights multiple times improves the accuracy of elastic angle measurement.

[0074] This embodiment is only an exemplary description of the present invention and does not limit its protection scope. Those skilled in the art may also make partial changes thereto. As long as they do not exceed the spirit of the present invention, they are within the protection scope of the present invention.

Claims

1. A wind tunnel turbojet engine model balance, characterized in that: The wind tunnel balance (1) comprises a wind tunnel balance (1), a balance rear bracket (2), a balance front bracket (3), a pulley adapter (9), a pulley (14), a weight plate (18), a weight string (19) and a spring body (20). The wind tunnel balance (1) is connected to an upper wall plate (21) of the wind tunnel through the balance rear bracket (2) and the balance front bracket (3). The balance rear bracket (2) and the balance front bracket (3) are connected through a reinforcement rod (7). The pulley adapter (9) is installed on the upper wall plate (21) of the wind tunnel. The pulley (14) is connected to the upper wall plate (21) of the wind tunnel through the pulley adapter (9). The wind tunnel upper wall plate (21) is connected, the rear end of the wind tunnel balance (1) is connected to the balance rear bracket (2), the front end of the wind tunnel balance (1) is connected to the spring body (20), the spring body (20) is arranged outside the reinforcement rod (7), one end of the steel belt (15) passes around the spring body (20) and is clamped by a clamping block (16) to form a loop, the other end of the steel belt (15) passes around a pulley (14) and is connected to a hanging rod (17), the hanging rod (17) is connected to a weight plate (18), and a weight string (19) is arranged on the weight plate (18).

2. A wind tunnel turbojet engine model balance according to claim 1, characterized in that: An extended fixing block (11) and a fixing plate (12) are arranged above the wind tunnel upper wall plate (21), the extended fixing block (11) is connected to the fixing plate (12), a connecting rod (8) is installed at the bottom of the extended fixing block (11), the connecting rod (8) passes through the wind tunnel upper wall plate (21) and is arranged in the wind tunnel, a balance rear bracket (2) and a balance front bracket (3) are installed on the connecting rod (8), screws pass through the wind tunnel upper wall plate (21) to connect the pulley adapter (9) and the fixing plate (12), a universal support (13) is connected to the bottom of the pulley adapter (9), and a pulley (14) is rotatably installed on the universal support (13).

3. A wind tunnel turbojet engine model balance according to claim 2, characterized in that: The rear end of the wind tunnel balance (1) is connected to the balance rear bracket (2) via an end face key (6), and the front end of the wind tunnel balance (1) is connected to the spring body (20) via the end face key (6).

4. A wind tunnel turbojet engine model balance according to claim 3, characterized in that: A left protective cover (4) and a right protective cover (5) are provided at the front end of the wind tunnel balance (1); the left protective cover (4) and the right protective cover (5) are connected to form a sleeve which is sleeved on the wind tunnel balance (1).

5. A wind tunnel turbojet engine model balance according to claim 4, characterized in that: The left protective cover (4) and the right protective cover (5) are made of aluminum material, and the diameter of the wind tunnel balance (1) is 100 mm.

6. A wind tunnel turbojet engine model balance according to claim 5, characterized in that: The interface between the universal support member (13) and the pulley adapter member (9) has a gap in the lift direction, and the gap height is 1 mm. A plurality of extended pads (10) are provided between the pulley adapter member (9) and the extended fixing block (11). Screws pass through the wind tunnel upper wall plate (21) and the extended pads (10) to connect the pulley adapter member (9) to the extended fixing block (11).

7. A method for calibrating the elastic angle of a wind tunnel turbojet engine model balance, the method being implemented by the wind tunnel turbojet engine model balance according to claim 6, characterized in that: The following steps are involved: Step 1: After the reference plane of the connecting rod (8) is leveled, it is installed on the extended fixing block (11) at the bottom of the wind tunnel upper wall plate (21), the balance rear bracket (2) is sleeved on the connecting rod (8) and fixed by screws and pins, and the rear ends of the balance rear bracket (2) and the wind tunnel balance (1) are connected by an end face key (6), and the wind tunnel balance (1) is not adjusted for γ angle; Step 2: Connect the balance rear bracket (2) and the four reinforcement rods (7) by means of screws, and connect the spring body (20) to the front end of the wind tunnel balance (1) by means of the end face key (6) after passing through the four reinforcement rods (7). The balance front bracket (3) is mounted on the connecting rod (8) and fixed by means of screws and pins. The balance front bracket (3), the balance rear bracket (2) and the four reinforcement rods (7) form a fixed end, thereby ensuring the rigidity of the fixed end of the wind tunnel balance (1); Step 3: Connect the pulley adapter (9) through the wind tunnel upper wall plate (21) and the fixing plate (12) by screws, and connect the pulley adapter (9) through the wind tunnel upper wall plate (21) and the extension pad (10) and the extension fixing block (11) by screws; Step 4: The universal support member (13) is two symmetrical flat plates, which are respectively embedded in the interfaces on both sides of the pulley adapter (9). Under the action of gravity, the universal support member (13) and the lower boundary limit contact of the interface of the universal support member (13) are tightened to fix the universal support member (13) and the pulley adapter (9). When the universal support member (13) and the pulley adapter (9) are connected, the pulley (14) is rotated by connecting the two symmetrical flat plates of the universal support member (13) through screws; Step 5: One end of the steel belt (15) is clamped by a clamping block (16) to form a loop and is put on the elastic body (20); the other end of the steel belt (15) is passed through the pulley (14) and connected to the hanging rod (17); the hanging rod (17) is connected to a weight plate (18); Step 6: Measure the distance between the center of the steel belt (15) and the front end of the balance rear bracket (2): , place a mass of The weight string (19) is used to measure the deformation difference of the bullet body (20) corresponding to the center of the steel belt (15) relative to the wind tunnel side wall plate under the influence of the weight string (19). ; Step 7: Set the yaw spring coefficient associated with the side force of the wind tunnel balance (1) to , the yaw elastic angular coefficient related to the yaw moment is , is the yaw angle caused by the load condition, and the corresponding formula is as follows: （1）； in and is the coefficient to be determined, g is the local gravitational acceleration, and is the lateral force and yaw moment generated by the weight; Step 8: Move the pulley adapter (9) along the axial direction of the model, and the steel belt (15) moves accordingly. The distance between the center of the steel belt (15) and the front end surface of the balance rear bracket (2) is measured to be , place a mass of The weight string (19) is used to measure the deformation difference of the bullet body (20) corresponding to the center of the steel belt (15) relative to the wind tunnel side wall plate under the influence of the weight string (19). ; Step 9: Settings The yaw angle caused by this load condition has the following corresponding formula: （2）； in and is the coefficient to be determined, and is the lateral force and yaw moment generated by the weight; Step 10: Combine formula (1) and formula (2) to obtain the elastic angle coefficient corresponding to the measured force and yaw moment and ; Step 11: Remove the steel belt (15) from the pulley (14), connect the steel belt (15) directly to the weight plate (18) and the weight string (19) through the hanging rod (17), and apply lift and pitch moment to the model under the action of gravity to obtain the elastic angular coefficient corresponding to the lift and pitch moment. and , the corresponding formula is as follows: （3）； （4）； in , is the lift force generated by the weight, , is the yaw moment generated by the weight, is the angle of attack produced by the weight; Each time loading is performed, the weights of different masses are applied and the average value is taken, that is, , is the average value of multiple application of weights, , The average of the yaw and pitch angles produced by applying weights multiple times improves the accuracy of elastic angle measurement.

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