A high-speed aircraft skin panel flutter characteristic test device and test method

Abstract

The present application belongs to the technical field of wind tunnel test, and discloses a kind of high-speed aircraft skin panel flutter characteristic test device and test method.The test device includes back pressure cavity, electromagnetic valve, back pressure cavity pressure sensor, control system and air pressure servo system;Back pressure cavity and air pressure servo drive system control the pressure difference of skin panel model two sides, according to the real-time control back pressure cavity pressure according to wind tunnel flow Mach number, test section static pressure, ensure that the pressure difference of skin panel model two sides is given value, suitable for carrying out the flutter characteristic test of high-speed aircraft skin panel of side wall support.The test method according to the flight condition of high-speed aircraft gives the pressure difference of panel flutter model two sides, sends instruction to air pressure servo system through control system, adjusts back pressure cavity pressure by changing back pressure cavity volume, and adjusts back pressure cavity pressure in real time according to the change of wind tunnel test section flow field static pressure during test, ensure the accuracy of test data.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of wind tunnel test, and particularly relates to a high-speed aircraft skin panel flutter characteristic test device and a test method. BACKGROUND

[0002] Panel flutter is a kind of aeroelastic instability phenomenon of aircraft surface skin structure due to the mutual coupling of aerodynamic force, inertial force and elastic force, and is a kind of self-excited vibration of a dynamic system. Unlike the classic lift surface flutter, the aerodynamic load of the panel flutter only acts on one surface of the panel, and due to the geometric nonlinearity caused by the large deformation of the panel surface, the panel flutter usually presents as amplitude-limited vibration, and long-term panel flutter will cause fatigue damage of the panel structure.

[0003] A large amount of work has been done by technical personnel to study the panel flutter characteristics of high-speed aircraft skin to provide technical support for the structural optimization design of high-speed aircraft. However, due to the difficulty in developing the test device, the early research mainly relies on theoretical analysis and numerical simulation, and the panel flutter characteristic test research under the ground environment is relatively limited, especially the back side of the panel flutter characteristic test model is the wind tunnel standing room, the pressure of the wind tunnel standing room is higher than the static pressure of the wind tunnel test section flow field, and the pressure difference changes greatly with the Mach number of the incoming flow, while the pressure difference between the two sides of the panel flutter characteristic test model is a given value, and can be changed in real time according to the static pressure of the test section flow field. At present, there is no suitable device that can be applied to the panel flutter characteristic test of high-speed aircraft skin in the published materials.

[0004] At present, it is urgent to develop a high-speed aircraft skin panel flutter characteristic test device and a test method. SUMMARY

[0005] One of the technical problems to be solved by the present application is to provide a high-speed aircraft skin panel flutter characteristic test device, and another technical problem to be solved by the present application is to provide a high-speed aircraft skin panel flutter characteristic test method.

[0006] The high-speed aircraft skin panel flutter characteristic test device of the present application has the characteristics that the test device comprises a back pressure cavity, an electromagnetic valve, a back pressure cavity pressure sensor, a control system and a pneumatic servo system; the control system comprises a control computer and a control cabinet placed outside the high-speed wind tunnel, the control cabinet is provided with an alternating current stabilized power supply, an electric cylinder alternating current servo driver, a cylinder motion controller, electrical protection devices and a pressure sensor acquisition card, the electrical protection devices protect the electrical devices in the control cabinet; the pneumatic servo system comprises an electric cylinder and a cylinder placed outside the high-speed wind tunnel, and the electric cylinder and the cylinder are powered by the alternating current stabilized power supply of the control cabinet.

[0007] The skin panel flutter model vertically projects on the side wall panel, cuts the corresponding vertical projection area on the side wall panel according to the vertical projection shape, installs a back pressure cavity with the same vertical projection shape as the vertical section shape at the gap of the side wall panel, and the depth of the back pressure cavity is less than the width of the standing chamber; the skin panel flutter model and the back pressure cavity form a closed cavity;

[0008] A back pressure cavity pressure sensor is installed in the back pressure cavity, and the back pressure cavity pressure sensor is connected with the control computer through a pressure sensor acquisition card;

[0009] An electromagnetic valve is installed on the side wall surface of the back pressure cavity, and the electromagnetic valve is connected with the control computer; when the electromagnetic valve is opened, the back pressure cavity is communicated with the standing chamber, and when the electromagnetic valve is closed, the back pressure cavity is closed with the standing chamber;

[0010] The back pressure cavity is connected with an air pipe, the control computer controls the air cylinder through an air cylinder alternating current servo driver and controls the air cylinder through an air cylinder motion controller, the air cylinder drives the air cylinder piston to exhaust or compress, and the air cylinder exhausts or intakes air through the air pipe;

[0011] The wind tunnel test section pressure sensor is connected with the control computer.

[0012] The high-speed aircraft skin panel flutter characteristic test method of the application comprises the following steps:

[0013] S10. A high-speed aircraft skin panel flutter characteristic test plan table is prepared, and a back pressure cavity and a high-speed wind tunnel test section static pressure difference adjustment ladder table is set;

[0014] S20. Before starting the high-speed wind tunnel, the electromagnetic valve is opened, and the back pressure cavity is communicated with the standing chamber;

[0015] S30. The high-speed wind tunnel is started, and the electromagnetic valve is closed after the high-speed wind tunnel flow field is stabilized;

[0016] S40. The control computer obtains the back pressure cavity static pressure through the back pressure cavity pressure sensor and obtains the high-speed wind tunnel test section static pressure through the wind tunnel test section pressure sensor, and calculates the static pressure difference between the back pressure cavity and the high-speed wind tunnel test section;

[0017] S50. According to the first static pressure difference value of the static pressure difference adjustment ladder table, the control computer sends a control instruction to the air pressure servo system, controls the air cylinder through the air cylinder motion controller, the air cylinder drives the air cylinder piston to exhaust or compress, and adjusts the back pressure cavity pressure through the air pipe, until the static pressure difference between the back pressure cavity and the high-speed wind tunnel test section reaches the first static pressure difference value, and the skin panel flutter model aerodynamic data is collected;

[0018] S60. Repeat step S50 until the skin panel flutter model aerodynamic data collection of the static pressure difference adjustment ladder table is completed;

[0019] S70. Open the electromagnetic valve, the back pressure chamber is communicated with the standing chamber;

[0020] S80. Close the high-speed wind tunnel, the high-speed aircraft skin panel flutter characteristic test is ended.

[0021] The high-speed aircraft skin panel flutter characteristic test device of the application adopts a back pressure chamber and a pneumatic servo driving system to control the pressure difference of the skin panel model on both sides, controls the pressure of the back pressure chamber according to the Mach number of the wind tunnel flow and the static pressure of the test section in real time, ensures that the pressure difference of the skin panel model on both sides is a given value, and is suitable for carrying out the high-speed aircraft skin panel flutter characteristic test of the side wall support.

[0022] The high-speed aircraft skin panel flutter characteristic test method of the application gives the pressure difference of the panel flutter model on both sides according to the flight working condition of the high-speed aircraft, sends instructions to the pneumatic servo system through the control system, adjusts the pressure of the back pressure chamber by changing the volume of the back pressure chamber, and adjusts the pressure of the back pressure chamber in real time according to the static pressure change of the wind tunnel test section flow field during the test, thereby ensuring the accuracy of the test data.

[0023] The high-speed aircraft skin panel flutter characteristic test device and test method of the application can realize real-time and accurate control of the static pressure pressure difference between the back pressure chamber of the high-speed wind tunnel aircraft skin panel flutter model and the wind tunnel test section flow, ensure that the initial deformation of the skin panel model reaches the set value during the test, meet the demand of the high-speed wind tunnel test of the aircraft skin panel flutter, and ensure the accuracy of the test results. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a structural schematic view of the high-speed aircraft skin panel flutter characteristic test device of the application.

[0025] In the figure, 1. standing chamber; 2. back pressure chamber; 3. skin panel flutter model; 4. electromagnetic valve; 5. back pressure chamber pressure sensor; 6. pneumatic servo system; 7. air pipe; 8. control cabinet; 9. control computer; 10. wind tunnel test section pressure sensor. DETAILED DESCRIPTION

[0026] The application will be described in detail below in combination with the drawings and examples.

[0027] Example 1

[0028] As Figure 1As shown, the high-speed aircraft skin panel flutter characteristic test device of the embodiment includes a back pressure cavity 2, a solenoid valve 4, a back pressure cavity pressure sensor 5, a control system, and a pneumatic servo system 6; the control system includes a control computer 9 and a control cabinet 8 arranged outside the high-speed wind tunnel, the control cabinet 8 is provided with an alternating current stabilized power supply, an electric cylinder alternating current servo driver, a cylinder motion controller, electrical protection devices, and a pressure sensor acquisition card, the electrical protection devices protect the electrical devices in the control cabinet 8; the pneumatic servo system 6 includes an electric cylinder and a cylinder arranged outside the high-speed wind tunnel, and the electric cylinder and the cylinder are powered by the alternating current stabilized power supply of the control cabinet 8;

[0029] The skin panel flutter model 3 is vertically projected on the side wall panel, the corresponding vertical projection area on the side wall panel is cut according to the vertical projection shape, a back pressure cavity 2 with the same vertical projection shape as the vertical section shape is installed at the gap of the side wall panel, and the depth of the back pressure cavity 2 is less than the width of the settling chamber 1; the skin panel flutter model 3 and the back pressure cavity 2 form a closed cavity;

[0030] The back pressure cavity 2 is provided with a back pressure cavity pressure sensor 5, and the back pressure cavity pressure sensor 5 is connected to the control computer 9 through the pressure sensor acquisition card;

[0031] The side wall surface of the back pressure cavity 2 is provided with a solenoid valve 4, and the solenoid valve 4 is connected to the control computer 9; when the solenoid valve 4 is opened, the back pressure cavity 2 is communicated with the settling chamber 1, and when the solenoid valve 4 is closed, the back pressure cavity 2 is closed with the settling chamber 1;

[0032] The back pressure cavity 2 is connected to an air pipe 7, the electric cylinder is controlled by the electric cylinder alternating current servo driver, and the cylinder is controlled by the cylinder motion controller; the electric cylinder drives the cylinder piston to suck or compress air, and the air is sucked or introduced from the back pressure cavity 2 through the air pipe 7;

[0033] The wind tunnel test section pressure sensor 10 is connected to the control computer 9.

[0034] The high-speed aircraft skin panel flutter characteristic test method of the embodiment includes the following steps:

[0035] S10. A high-speed aircraft skin panel flutter characteristic test plan table is prepared, and a static pressure difference adjustment step sequence table of the back pressure cavity 2 and the high-speed wind tunnel test section is set;

[0036] S20. Before starting the high-speed wind tunnel, open the solenoid valve 4, and the back pressure cavity 2 is communicated with the settling chamber 1;

[0037] S30. Start the high-speed wind tunnel, and close the solenoid valve 4 after the flow field of the high-speed wind tunnel is stabilized;

[0038] S40. The control computer 9 acquires the static pressure of the back pressure chamber 2 through the back pressure chamber pressure sensor 5 and acquires the static pressure of the high-speed wind tunnel test section through the wind tunnel test section pressure sensor 10, and calculates the static pressure difference between the back pressure chamber 2 and the high-speed wind tunnel test section;

[0039] S50. According to the static pressure difference adjustment step sequence table, the first static pressure difference value is adjusted, the control computer 9 sends a control instruction to the air pressure servo system 6, the air cylinder is controlled through the air cylinder motion controller, the air cylinder piston is driven to exhaust or compress, and the air is exhausted or introduced from the back pressure chamber 2 through the air pipe 7, the back pressure chamber pressure is adjusted, and the static pressure difference between the back pressure chamber 2 and the high-speed wind tunnel test section reaches the first static pressure difference value, and the skin panel flutter model 3 aerodynamic data is collected;

[0040] S60. Repeat step S50 until the skin panel flutter model 3 aerodynamic data collection of the static pressure difference adjustment step sequence table is completed;

[0041] S70. Open the electromagnetic valve 4, and the back pressure chamber 2 is communicated with the standing chamber 1;

[0042] S80. Close the high-speed wind tunnel, and the high-speed aircraft skin panel flutter characteristic test is completed.

[0043] The high-speed aircraft skin panel flutter characteristic test device of the embodiment is applied to a 0.6-meter three-speed wind tunnel, wherein the size of the back pressure chamber 2 is: 500mm (length) * 400mm (width) * 150mm (height) = 30000000mm 3 ; The driving air cylinder of the air pressure servo system 6 is a customized electric push cylinder with a cylinder diameter of 200mm, a stroke of 1000mm, a limit speed of 800mm / s, and a rated thrust of 2000N.

[0044] The cylinder volume of the customized electric push cylinder: π(200 / 2)2*1000 = 31415927mm 3 ;

[0045] The cylinder volume change per second of the customized electric push cylinder: π(200 / 2)2*800 = 25132741mm 3 ;

[0046] It is assumed that the initial pressure is the conventional test pressure of Mach 3, and the pressure value is 9800Pa;

[0047] According to the Clapeyron equation P*V = const, at the initial moment, the air pressure servo system 6 is located at the maximum volume position, which is the volume of the cylinder plus the volume of the back pressure chamber 2, and the specific value is 61415927mm 3 ; At the completion moment, the air pressure servo system 6 is located at the minimum volume position, which is the volume of the back pressure chamber 2, and the specific value is 30000000mm 3The pressure value of the back pressure cavity 2 at the completion time is 61415927 / 30000000*9800=20062Pa, which is about 2.05 times of the pressure value of the back pressure cavity 2 at the initial time.

[0048] Under the condition of standard atmospheric pressure, the air pressure variation of the customized electric push cylinder is: 101325*(25132741 / (25132741+30000000))=46190Pa.

[0049] If the pressure of the test section is increased by no more than 1000Pa / s during the process of the high-speed aircraft skin panel flutter characteristic test device, the pressure increasing speed of the back pressure cavity 2 is no more than 1000Pa / s, and the pressure response time is: 1000 / 46190*1000ms=21.65ms, which is lower than 30ms.

[0050] Although the embodiments of the present application have been disclosed as above, it is not limited to the application listed in the specification and the embodiments, and can be applied to various fields suitable for the present application. For those skilled in the art, other improvements and refinements can be easily realized without departing from the principles of the present application, and the present application is not limited to specific details and the figures shown and described herein.

Claims

1. A high-speed aircraft skin panel flutter characteristics test apparatus, characterized by, The test device comprises a back pressure cavity (2), an electromagnetic valve (4), a back pressure cavity pressure sensor (5), a control system and a pneumatic servo system (6); the control system comprises a control computer (9) and a control cabinet (8) arranged outside the high-speed wind tunnel, the control cabinet (8) is internally provided with an alternating current stabilized power supply, an electric cylinder alternating current servo driver, a cylinder motion controller, electrical protection devices and a pressure sensor acquisition card, the electrical protection devices protect the electrical devices in the control cabinet (8); the pneumatic servo system (6) comprises an electric cylinder and a cylinder arranged outside the high-speed wind tunnel, and the electric cylinder and the cylinder are powered by the alternating current stabilized power supply of the control cabinet (8); The skin wall plate flutter model (3) is vertically projected on the side wall panel, the corresponding vertical projection area on the side wall panel is cut according to the vertical projection shape, a back pressure cavity (2) with the same vertical projection shape as the vertical section shape is installed at the gap of the side wall panel, and the depth of the back pressure cavity (2) is less than the width of the standing chamber (1); the skin wall plate flutter model (3) and the back pressure cavity (2) form a closed cavity; The back pressure cavity (2) is internally provided with a back pressure cavity pressure sensor (5), and the back pressure cavity pressure sensor (5) is connected with the control computer (9) through the pressure sensor acquisition card; An electromagnetic valve (4) is arranged on the side wall of the back pressure cavity (2), and the electromagnetic valve (4) is connected with the control computer (9); when the electromagnetic valve (4) is opened, the back pressure cavity (2) is communicated with the standing chamber (1), and when the electromagnetic valve (4) is closed, the back pressure cavity (2) is closed with the standing chamber (1); The back pressure cavity (2) is connected with an air passage (7), the electric cylinder is controlled by the electric cylinder alternating current servo driver, the cylinder is controlled by the cylinder motion controller, the cylinder piston is driven by the electric cylinder to suck or compress air, and the air is sucked or introduced from the back pressure cavity (2) through the air passage (7); The wind tunnel test section pressure sensor (10) is connected with the control computer (9).

2. A method of testing the flutter characteristics of a high-speed aircraft skin panel according to the apparatus for testing the flutter characteristics of a high-speed aircraft skin panel according to claim 1, characterized by, The method comprises the following steps: S10. A high-speed aircraft skin wall plate flutter characteristic test plan table is prepared, and a back pressure cavity (2) and a high-speed wind tunnel test section static pressure difference adjustment ladder table are set; S20. Before starting the high-speed wind tunnel, the electromagnetic valve (4) is opened, and the back pressure cavity (2) is communicated with the standing chamber (1); S30. The high-speed wind tunnel is started, and the electromagnetic valve (4) is closed after the flow field of the high-speed wind tunnel is stabilized; S40. The control computer (9) obtains the static pressure of the back pressure cavity (2) through the back pressure cavity pressure sensor (5), obtains the static pressure of the high-speed wind tunnel test section through the wind tunnel test section pressure sensor (10), and calculates the static pressure difference between the back pressure cavity (2) and the high-speed wind tunnel test section; S50. According to the first static pressure difference value of the static pressure difference adjustment ladder table, the control computer (9) sends a control instruction to the pneumatic servo system (6), controls the cylinder through the cylinder motion controller, drives the cylinder piston by the electric cylinder to suck or compress air, adjusts the pressure of the back pressure cavity (2) by sucking or introducing air from the back pressure cavity (2) through the air passage (7), until the static pressure difference between the back pressure cavity (2) and the high-speed wind tunnel test section reaches the first static pressure difference value, and the skin wall plate flutter model (3) aerodynamic data is collected; S60. Repeat step S50 until the skin panel flutter model (3) aerodynamic data acquisition of the static pressure difference adjustment ladder sequence table is completed; S70. Open the electromagnetic valve (4), and the back pressure cavity (2) is communicated with the standing chamber (1); S80. Close the high-speed wind tunnel, and the high-speed aircraft skin panel flutter characteristic test is ended.

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