Attack angle sensor following characteristic wind tunnel test device

Abstract

The utility model discloses an attack angle sensor following characteristic wind tunnel test device, which can be installed in a wind tunnel through a side window support mode, and outputs sine wave excitation with specific frequency and amplitude through an external driving motor, an eccentric bearing and an L-shaped link rod to control the attack angle change of a side window transmission mechanism. One end of the side window transmission mechanism is directly connected with the weather cock type attack angle sensor, the other end of the side window transmission mechanism is directly connected with the angle sensor, data of the attack angle sensor and data of the angle sensor are compared and processed in real time through the dynamic acquisition instrument, and the dynamic following response characteristic of the attack angle sensor is obtained. The test device is convenient in state replacement and high in measurement precision, and can simply and effectively obtain the detection characteristics of the attack angle sensor under different flow field environments and different excitation frequencies and amplitudes.

Description

Technical Field

[0001] The utility model relates to a wind tunnel test device for an aircraft weathervane angle of attack sensor, which is used to measure the dynamic following characteristics of the weathervane angle of attack sensor in a sub-transmission and supersonic flight environment and belongs to the technical field of wind tunnel test devices. Background Art

[0002] The angle of attack is an important parameter of the real-time status of the aircraft. It is the core indicator for judging the flight performance and control stability of the aircraft. It is also the core data for aircraft loss of control and stall detection. On the one hand, the angle of attack system can present accurate flight angle of attack, stall angle of attack and other important information. On the other hand, it can also input angle of attack signals to provide important assistance for fire control calculations, making weapon projection more accurate.

[0003] The wind vane angle of attack sensor is mainly composed of a wind vane, a rotating shaft, and an angle sensor. If the angle of attack of the aircraft changes relative to the direction of the airflow, the flow around it will also change. At this time, the flow field where the wind vane is located will also change, and the aerodynamic forces acting on the upper and lower surfaces of the wind vane will no longer be equal, forming a torque that forces the wind vane to rotate around the axis until the symmetry line of the wedge-shaped section of the wind vane is consistent with the direction of the airflow, reaching a zero resultant torque and stopping the rotation. At this time, the angle the wind vane has rotated is the actual angle of attack of the aircraft.

[0004] The relationship between the detected angle of attack of the angle of attack sensor and the actual flight angle of attack is affected by factors such as the installation position and the flight flow field. In supersonic and hypersonic flight environments, the flow field around the aircraft changes dramatically, which will affect the detection characteristics of the angle of attack sensor to a certain extent. The detection characteristics of the angle of attack sensor require that it can quickly respond to changes in the angle of attack of the aircraft and immediately feed back the measured angle of attack to the flight control system, which requires the angle of attack sensor to have a high follow-up response characteristic. To this end, it is necessary to design a test device that can give different excitation frequencies and amplitudes to the angle of attack sensor in the wind tunnel, and obtain the detection characteristics of the angle of attack sensor by adjusting the flow field environment in the wind tunnel. Utility Model Content

[0005] The technical problem solved by the present application is to overcome the shortcomings of the prior art and provide a wind tunnel test device for angle of attack sensor tracking characteristics. The test device can be installed in a wind tunnel by means of side window support, and the angle of attack change of the test model in the wind tunnel can be controlled by external different excitation frequencies and amplitudes, so as to obtain the dynamic response tracking characteristics of the angle of attack sensor in sub-transonic airflow.

[0006] The technical solutions provided by this application are as follows:

[0007] An angle of attack sensor following characteristic wind tunnel test device comprises a wind tunnel, a side window platform, a connecting rod, an eccentric bearing, an angle of attack sensor and an angle sensor;

[0008] The side window platform is fixedly connected to the outer wall of the wind tunnel, and the side window platform covers the position of the window;

[0009] The angle of attack sensor includes a base, a wind vane, a wind vane transmission shaft and a measuring sensor. The base is fixed in the side window platform. The wind vane transmission shaft is rotatably connected to the base. The wind vane is connected to one end of the wind vane transmission shaft, and the wind vane extends into the wind tunnel through the window. The other end of the wind vane transmission shaft extends out of the side window platform and is connected to the output shaft of the driving motor through a connecting rod and an eccentric bearing. The driving motor is used to drive the wind vane transmission shaft to periodically rotate forward and reverse. The driving motor is fixedly connected to the outer wall of the wind tunnel. The measuring sensor is used to measure the rotation angle of the wind vane transmission shaft.

[0010] The angle sensor is fixedly connected to the side window platform, and the angle sensor is used to accurately measure the angle change of the wind vane transmission shaft.

[0011] The connecting rod includes a first rod and a second rod, one end of the first rod is fixedly connected to the weather vane transmission shaft, the other end of the first rod is rotatably connected to the second rod, the other end of the second rod is connected to an eccentric bearing, the outer ring of the eccentric bearing is fixed to the second rod, the output shaft of the driving motor is inserted into the inner ring of the eccentric bearing and fixedly connected to the inner ring, and the inner ring axis of the eccentric bearing does not coincide with the outer ring axis.

[0012] The connecting rod also includes a cylinder, which is sleeved on the outside of the weather vane transmission shaft. The outer wall of the weather vane transmission shaft is fixedly connected with a first angle key, and the outer wall of the cylinder is fixedly connected with a second angle key; the outer sleeve of the weather vane transmission shaft is provided with an angle lock, and the angle lock has a first key slot and a second key slot, the first key slot cooperates with the first angle key, and the second key slot cooperates with the second angle key.

[0013] The first angle key and the second angle key both extend along the axial direction of the cylinder, and the first keyway and the second keyway penetrate the angle lock along the axial direction of the angle lock.

[0014] The first angle key is located on a side of the cylinder away from the side window platform.

[0015] A nut is threadedly connected on the weather vane transmission shaft, and the nut is located on a side of the angle lock away from the side window platform.

[0016] The outer wall surface of the cylinder is provided with a stepped surface perpendicular to the axis of the cylinder. When the nut is locked on the side of the angle lock away from the side window platform, the end surface of the angle lock contacts the stepped surface.

[0017] The angle sensor is a potentiometer.

[0018] In summary, this application at least includes the following beneficial technical effects:

[0019] (1) By supporting the side windows, the angle sensor, motor, support connectors and other test components are installed outside the wind tunnel, leaving only the wind vane of the angle of attack sensor in the flow field. This reduces the interference of the test device on the flow field in the wind tunnel, and also reduces the impact of airflow on the measurement and control accuracy of the angle sensor, motor, etc.

[0020] (2) Through design analysis, a dynamic signal acquisition instrument is used to synchronously and real-time collect the output signal of the wind vane angle of attack sensor and the output signal of the angle sensor, so that the dynamic response characteristics of the wind vane angle of attack sensor under different flow field environments in the wind tunnel can be obtained simply and efficiently.

[0021] (3) Through the eccentricity between the motor shaft and the bearing shaft, the output signal of the motor is converted into a sinusoidal wave excitation, thereby driving the connecting rod to swing periodically, and by replacing different eccentric bearing connectors, different swing frequency and amplitude requirements can be achieved.

[0022] (4) Modeling and analysis of errors caused by mechanical reasons were carried out to strictly control the main error sources (such as fit clearance and bending rod deformation), thereby improving the control and acquisition accuracy of the test attack angle.

[0023] (5) Through the design of the angle lock, the dynamic response characteristic test of the angle of attack sensor at different angles can be quickly realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of a wind tunnel test device for the following characteristics of an angle of attack sensor;

[0025] Figure 2 It is a three-dimensional view of a wind tunnel test device for the angle of attack sensor’s following characteristics;

[0026] Figure 3 yes Figure 2 Cross-sectional view at AA in the middle.

[0027] Description of the accompanying figures: 1. Wind tunnel; 11. Fixing plate on the outer wall of the tunnel; 14. Driving motor;

[0028] 2. Side window platform; 21. Support; 22. Angle sensor;

[0029] 31. base; 32. weather vane; 33. weather vane transmission shaft; 16. first angle key;

[0030] 4. connecting rod; 41. first rod; 42. second rod; 43. cylinder; 17. second angle key;

[0031] 5. Eccentric bearing; 6. Angle lock. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the present utility model clearer, the implementation methods disclosed in the present utility model will be further described in detail below in conjunction with the accompanying drawings.

[0033] The present application embodiment discloses a wind tunnel test device for the following characteristics of an angle of attack sensor, such as Figure 1 As shown, it includes a wind tunnel 1, an angle of attack sensor, a side window platform 2, a tunnel outer wall fixing plate 11, a connecting rod 4, an eccentric bearing 5, an angle lock 6, a driving motor 14 and an angle sensor (potentiometer) 22.

[0034] The wind tunnel 1 is provided with a window, a side window platform 2 is fixedly connected to the outer wall of the wind tunnel, and the side window platform 2 covers the position of the window, an angle of attack sensor is connected to the side window platform 2, and the angle of attack sensor extends into the wind tunnel through the window.

[0035] The angle of attack sensor includes a base 31, a weather vane 32, a weather vane transmission shaft 33 and a measuring sensor. The base 31 is fixed in the side window platform 2 through the support 21. The weather vane transmission shaft 33 is rotatably connected to the base 31. The weather vane 32 is connected to one end of the weather vane transmission shaft 33, and the weather vane 32 extends into the wind tunnel 1. The other end of the weather vane transmission shaft 33 extends out of the side window platform 2, and the end of the weather vane transmission shaft extending out of the side window platform 2 is connected to the output shaft of the drive motor 14 through the connecting rod 4 and the eccentric bearing 5. The outer wall fixing plate 11 of the tunnel is fixedly connected to the outer wall surface of the wind tunnel 1, and the drive motor 14 is fixedly connected to the outer wall fixing plate 11 of the tunnel through the motor support. The measuring sensor is used to measure the rotation angle of the weather vane transmission shaft 33.

[0036] like Figure 2 and Figure 3 As shown, the connecting rod includes a first rod 41, a second rod 42 and a cylinder 43, one end of the first rod 41 is fixedly connected to the cylinder 43, the other end of the first rod 41 is rotatably connected to the second rod 42, and the other end of the second rod 42 is connected to the output shaft of the driving motor 14 through the eccentric bearing 5. The cylinder 43 is sleeved on the outside of the weather vane transmission shaft 33, and the cylinder 43 and the weather vane transmission shaft 33 are fixed at an angle by an angle lock 6. At this time, the cylinder 43 is coaxial with the weather vane transmission shaft 33, and the rotation axis of the first rod 41 and the second rod 42 is parallel to the axis of the cylinder 43. The outer ring of the eccentric bearing 5 is fixed to the second rod 42, and the axis of the outer ring of the eccentric bearing 5 is parallel to the axis of the cylinder 43. The output shaft of the driving motor 14 is inserted into the inner ring of the eccentric bearing 5 and fixedly connected to the inner ring, and the axis of the inner ring of the eccentric bearing 5 does not coincide with the axis of the outer ring.

[0037] The driving motor 14 is connected to the connecting rod 4 through the eccentric bearing 5. When the driving motor 14 rotates, it produces an effect similar to the rotation of a cam and outputs excitation in the form of a sine wave, thereby driving the connecting rod 4 to swing periodically. By replacing the eccentric bearing 5, the requirements of different swing frequencies and amplitudes can be achieved.

[0038] The angle lock 6 is sleeved on the outside of the cylinder 43 and the weathervane transmission shaft 33. The outer wall surface of the weathervane transmission shaft 33 is fixedly connected with the first angle key 16. The outer wall surface of the cylinder 43 is fixedly connected with the second angle key 17. The first angle key 16 is located on the side of the cylinder 43 away from the side window platform 2. The angle lock 6 is provided with a first keyway and a second keyway. The first keyway cooperates with the first angle key 16, and the second keyway cooperates with the second angle key 17. When the angle lock 6 is sleeved on the outside of the cylinder 43 and the weathervane transmission shaft 33, and the first keyway cooperates with the first angle key 16, and the second keyway cooperates with the second angle key 17, the cylinder 43 and the weathervane transmission shaft 33 cannot rotate relative to each other. The first angle key 16 and the second angle key 17 both extend along the axial direction of the cylinder 43. The first keyway and the second keyway penetrate the angle lock 6 along the axial direction of the angle lock 6, so that the angle lock 6 can move along the axial direction of the cylinder 43 and can be detached from the cylinder 43 and the weathervane transmission shaft 33. There are multiple angle locks 6, and the angles between the lines connecting the first key slots and the axis of the angle locks 6 and the lines connecting the second key slots and the axis of the angle locks 6 are different. The angle of attack of the angle of attack sensor can be adjusted by replacing different angle locks 6. A nut for fixing the angle lock 6 is threadedly connected on the wind vane transmission shaft 33. Through the design of the angle lock 6, the dynamic response characteristic test of the angle of attack sensor at different angles can be realized.

[0039] The outer wall surface of the cylinder 43 is stepped to form a stepped surface. When the nut is locked on the side of the angle lock 6 facing away from the side window platform 2, the end surface of the angle lock 6 contacts the stepped surface.

[0040] The angle sensor 22 is a potentiometer, which is fixedly connected to the side window platform 2. The angle sensor 22 is used to accurately measure the angle change of the wind vane transmission shaft 33. The attack angle sensor also measures the attack angle change of the wind vane transmission shaft 33, and compares the output signal measured by the angle sensor 3 with that measured by the dynamic acquisition device in real time to achieve the follow-up characteristic test of the attack angle sensor.

[0041] The connecting rod 4 must ensure a certain rigidity, and the connecting rod 4 is closely matched with the weather vane transmission shaft 33. By eliminating the deformation and assembly clearance error of the connecting rod 4, the accuracy required for the test can be met.

[0042] One end of the wind vane transmission shaft 33 is directly connected to the angle sensor 22, and the other end is connected to the wind vane of the wind vane angle of attack sensor, which ensures the measurement consistency between the angle of attack sensor and the angle sensor 22 and can well test the dynamic following characteristics of the angle of attack sensor.

[0043] The wind vane drive shaft must have a certain rigidity in the torsion direction around its axis; on the other hand, a certain deflection must be ensured in the up and down, left and right bending directions to ensure the measurement precision and accuracy of the angle sensor 22 and the wind vane angle of attack sensor.

[0044] The test system can measure the dynamic response characteristics of the wind vane angle of attack sensor under different frequencies and amplitudes in different flow field environments according to the needs. The first step is to start the valve of the wind tunnel 1 to establish a flow field under a specific Mach number, so that the wedge-shaped cross-section symmetry line of the wind vane 32 of the angle of attack sensor is consistent with the airflow direction. Next, the dynamic signal acquisition instrument is turned on to monitor the signal changes of the measuring sensor and the angle sensor 12 of the angle of attack sensor. The real-time angle of attack is calculated by the pre-calibrated function formula, and the external drive motor 14 is driven to make the wind vane transmission shaft 33 vibrate sinusoidally around the wind vane axis. The dynamic characteristics of the wind vane angle of attack sensor can be obtained by comparing the dynamic signal acquisition instrument with the computer to synchronously collect the output signals of the wind vane angle of attack sensor and the angle sensor in real time.

[0045] The external drive motor 14 is used to realize dynamic control of different frequencies and amplitudes of the angle of attack sensor, and the dynamic following characteristics of the wind vane angle of attack sensor under different Mach numbers and different angles of attack are obtained according to the test requirements. The specific measurement method is as follows:

[0046] (1) Start the wind tunnel valve 1 to establish the flow field at a specific Mach number;

[0047] (2) driving an external drive motor 14, and converting the rotation of the drive motor 14 into a change in the angle of attack of the wind vane transmission shaft 33 by means of the eccentric bearing 5, the connecting rod 4 and other systems, while the output signals of the angle of attack sensor and the angle sensor 33 are collected in real time by a dynamic signal collector;

[0048] (3) By comparing the output signals of the angle of attack sensor's measuring sensor and the angle sensor 22 through a computer, the dynamic following characteristics of the angle of attack sensor under different flow field environments are obtained.

[0049] The contents not described in detail in this application specification belong to the common knowledge of those skilled in the art.

[0050] The present application is described in detail above in conjunction with specific implementation methods and exemplary examples, but these descriptions cannot be understood as limiting the present application. Those skilled in the art understand that, without departing from the spirit and scope of the present application, a variety of equivalent replacements, modifications or improvements can be made to the technical solution of the present application and its implementation methods, all of which fall within the scope of the present application. The scope of protection of the present application shall be subject to the attached claims.

Claims

1. A wind tunnel test device for angle of attack sensor following characteristics, characterized in that: It comprises a wind tunnel (1), a side window platform (2), a connecting rod (4), an eccentric bearing (5), an angle of attack sensor and an angle sensor (22); The side window platform (2) is fixedly connected to the outer wall of the wind tunnel, and the side window platform (2) covers the position of the window; The angle of attack sensor comprises a base (31), a weather vane (32), a weather vane transmission shaft (33) and a measuring sensor. The base (31) is fixed in the side window platform (2). The weather vane transmission shaft (33) is rotatably connected to the base (31). The weather vane (32) is connected to one end of the weather vane transmission shaft (33), and the weather vane (32) extends into the wind tunnel (1) through the window. The other end of the weather vane transmission shaft (33) extends out of the side window platform (2) and is connected to the output shaft of a driving motor (14) through a connecting rod (4) and an eccentric bearing (5). The driving motor (14) is used to drive the weather vane transmission shaft (33) to periodically rotate forward and reverse. The driving motor (14) is fixedly connected to the outer wall of the wind tunnel (1). The measuring sensor is used to measure the rotation angle of the weather vane transmission shaft (33). The angle sensor (22) is fixedly connected to the side window platform (2). The angle sensor (22) is used to accurately measure the angle change of the weather vane transmission shaft (33).

2. The wind tunnel test device for the following characteristics of an angle of attack sensor according to claim 1, characterized in that: The connecting rod comprises a first rod (41) and a second rod (42), one end of the first rod (41) is fixedly connected to the weather vane transmission shaft (33), the other end of the first rod (41) is rotatably connected to the second rod (42), the other end of the second rod (42) is connected to the eccentric bearing (5), the outer ring of the eccentric bearing (5) is fixed to the second rod (42), the output shaft of the driving motor (14) is inserted into the inner ring of the eccentric bearing (5) and fixedly connected to the inner ring, and the inner ring axis of the eccentric bearing (5) does not coincide with the outer ring axis.

3. The wind tunnel test device for the following characteristics of an angle of attack sensor according to claim 2, characterized in that: The connecting rod also includes a cylinder (43), which is sleeved on the outside of the weather vane transmission shaft (33), and the outer wall surface of the weather vane transmission shaft (33) is fixedly connected with a first angle key (16), and the outer wall surface of the cylinder (43) is fixedly connected with a second angle key (17); the outer wall of the weather vane transmission shaft (33) is provided with an angle lock (6), and the angle lock (6) is provided with a first key slot and a second key slot, the first key slot cooperates with the first angle key (16), and the second key slot cooperates with the second angle key (17).

4. The wind tunnel test device for the following characteristics of an angle of attack sensor according to claim 3, characterized in that: The first angle key (16) and the second angle key (17) both extend along the axial direction of the cylinder (43), and the first keyway and the second keyway penetrate the angle lock (6) along the axial direction of the angle lock (6).

5. The wind tunnel test device for the following characteristics of an angle of attack sensor according to claim 3, characterized in that: The first angle key (16) is located on a side of the cylinder (43) facing away from the side window platform (2).

6. The wind tunnel test device for the following characteristics of an angle of attack sensor according to claim 3, characterized in that: The weather vane transmission shaft (33) is threadedly connected with a nut, which is located on a side of the angle lock (6) away from the side window platform (2).

7. The wind tunnel test device for the following characteristics of an angle of attack sensor according to claim 6, characterized in that: The outer wall surface of the cylinder (43) is provided with a stepped surface perpendicular to the axis of the cylinder (43), and when the nut is locked on the side of the angle lock (6) facing away from the side window platform (2), the end surface of the angle lock (6) contacts the stepped surface.

8. The wind tunnel test device for the following characteristics of an angle of attack sensor according to claim 1, characterized in that: The angle sensor (22) is a potentiometer.

Images