Testing device and method for dynamic derivative wind tunnel test

Abstract

The invention belongs to the technical field of aerodynamic wind tunnel tests, and discloses a test device and method for a dynamic derivative wind tunnel test, and the device comprises an aircraft model which is formed by assembling a nose, a middle fuselage, a rear fuselage, a balance, wings and an empennage; the oscillation mechanism is provided with an adapter, and the adapter is connected with the balance; and one end of the wind tunnel strut is connected with the wind tunnel attitude control system and the other end is connected with the oscillation mechanism. The problem that an existing dynamic derivative wind tunnel test model and a test device are low in efficiency is solved, heaving, sidesway, yawing, pitching and rolling oscillation of the model are achieved by replacing the adapters, and the test efficiency of a dynamic derivative wind tunnel test can be effectively improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of aerodynamic wind tunnel testing, and in particular relates to a testing device and method for dynamic derivative wind tunnel testing. Background Art

[0002] During the aircraft design process, aerodynamic performance analysis and comprehensive design are essential. First, it is necessary to understand the aerodynamic force and torque characteristics of the aircraft under steady and unsteady flight conditions. Simultaneously, flight stability must be predicted. This requires an aerodynamic representation that can not only provide the six-component aerodynamic forces but also provide flight stability criteria. In a linear aerodynamic system, the derivatives of aerodynamic forces and torques serve as such criteria. The derivatives of aerodynamic forces and torques with respect to angular displacement are called static derivatives, while the derivatives of aerodynamic forces and torques with respect to angular velocity are called dynamic derivatives. Dynamic derivatives are the derivatives of the six aerodynamic coefficients (i.e., the three force and three torque coefficients in a three-dimensional Cartesian coordinate system) with respect to the time rate of change of the aircraft's attitude parameters. There are 36 dynamic derivatives in total, of which the three direct damping derivatives, three time-lag derivatives, two cross derivatives, and four cross-coupling derivatives have the greatest impact on aircraft performance. Dynamic derivatives are used to describe the aerodynamic characteristics of an aircraft during maneuvers and when subjected to disturbances. These are essential aerodynamic parameters for aircraft aerodynamic performance design, control systems, and overall design. Throughout the various stages of aircraft design, as the aerodynamic shape is adjusted, designers must understand its dynamic aerodynamic characteristics and gradually improve them to enhance the flight performance and flight quality of the final shape. Currently, the primary methods for obtaining dynamic derivatives include engineering estimation, CFD calculations, wind tunnel testing, and flight testing.

[0003] Generally speaking, at low angles of attack and in attached flow conditions, the dynamic derivatives of an aircraft can be estimated using engineering estimates. Furthermore, within this small angle of attack range, even under varying flight conditions, the dynamic derivatives vary only slightly. Therefore, using a specific dynamic derivative value for flight dynamics analysis can meet the requirements. However, engineering estimates can only provide a very rough estimate, and during the aircraft design process, it is impossible to determine the difference between two similar configurations.

[0004] With the development of computational fluid dynamics (CFD), the use of theoretical methods to calculate aircraft dynamic derivatives has become a feasible and efficient approach in aircraft design. This method can be used to calculate dynamic derivatives for aircraft with complex shapes and under a variety of flight conditions, providing a low-cost estimate of dynamic derivative values ​​for each state. However, as the angle of attack increases and the aircraft's shape becomes more complex, dynamic derivatives become more dependent on factors such as the formation and breakup of flow separation vortices. CFD is difficult to simulate in dynamic conditions, thus limiting its application.

[0005] Wind tunnel testing can reproducibly provide a large amount of test data and realistically simulate flight environments, making it an effective method for measuring dynamic derivatives. It can conveniently provide dynamic derivatives under various flight conditions. Currently, single-degree-of-freedom forced vibration equipment is commonly used in low-speed wind tunnels to conduct dynamic derivative wind tunnel testing. These tests can generally detect three angular vibrations: pitch, yaw, and roll, and two translational vibrations: heave and lateral translation. These tests are typically conducted in specially designed open wind tunnels, or require a vibration control mechanism to be placed outside the wind tunnel, with a long strut extending into the wind tunnel and connected to the model to control the model's vibration. Dedicated equipment is required for each vibration mode. To minimize interference with the equipment's dynamic derivative measurements, the model struts are typically designed to be relatively long. Consequently, the model's amplitude is relatively large to ensure accurate measurement of various motion modes. To prevent the model from colliding with the wind tunnel walls, strict restrictions are placed on the model size, resulting in a relatively small scale and a low test Reynolds number, which reduces the accuracy of the dynamic derivative measurements. At the same time, since different vibration modes require the replacement of different test devices, the entire model needs to be disassembled and assembled during the test, resulting in low test efficiency. Summary of the Invention

[0006] The object of the present invention is to provide a test device and method for dynamic derivative wind tunnel tests, which are used to solve the technical problem of low efficiency of existing dynamic derivative wind tunnel test models and test devices. The test device can significantly increase the size of the model, improve the stiffness of the model, and reduce the weight of the model. In addition, the conversion of vibration modes such as pitch, yaw, and roll can be achieved by simply replacing the conversion joint, without disassembling the entire model, which can effectively improve the test efficiency of dynamic derivative wind tunnel tests.

[0007] The technical solution of the present invention is achieved as follows: In a first aspect, the present invention provides a test apparatus for a dynamic derivative wind tunnel test, comprising: An aircraft model, which is assembled from a nose, mid-fuselage, rear fuselage, balance, wings, and tail; an oscillating mechanism having an adapter connected to a balance; The wind tunnel support rod has one end connected to the wind tunnel attitude control system and the other end connected to the oscillation mechanism.

[0008] As a further solution of the present invention: the oscillation mechanism includes a yaw oscillation mechanism, a pitch oscillation mechanism and a roll oscillation mechanism. By designing and replacing three adapters, the heave, side shift, yaw, pitch and roll oscillations of the aircraft model can be achieved.

[0009] As a further solution of the present invention: the adapter of the yaw oscillation mechanism is a yaw oscillation balance seat, and the yaw oscillation balance seat has a first mounting part and a second mounting part. The first mounting part is designed to be in a "dustpan" shape, and the balance is fixedly connected to the first mounting part. The second mounting part has a flat connecting surface and is fixedly connected to the upper end of the wind tunnel support rod.

[0010] As a further solution of the present invention: the pitch oscillation mechanism also includes a pitch oscillation base and a power pull rod, and its adapter is a pitch oscillation balance seat. The pitch oscillation balance seat has a third mounting part and a fourth mounting part. The third mounting part is designed to be in the shape of a "dustpan", and the balance is fixedly connected to the third mounting part. The pitch oscillation base has a flat connecting surface, which is fixedly connected to the upper end of the wind tunnel support rod, and connecting ears are provided on both sides. The fourth mounting part is hinged to the pitch oscillation base at one end close to the third mounting part, and the other end is hinged to one end of the power pull rod. The other end of the power pull rod is connected to the wind tunnel attitude control system.

[0011] As a further solution of the present invention: the roll oscillation mechanism also includes a roll oscillation base, an eccentric slider, a slider and a power pull rod, and its adapter is a roll oscillation balance seat, the roll oscillation balance seat has a fifth mounting part and a sixth mounting part, the fifth mounting part is designed to be in the shape of a "dustpan", the balance is fixedly connected to the fifth mounting part, the sixth mounting part is designed to be in the shape of an eccentric shaft, which includes a first shaft segment and a second shaft segment, the two are not coaxial, the roll oscillation base has a flat connecting surface, which is fixedly connected to the upper end of the wind tunnel support rod, the roll oscillation base is hinged to the first shaft segment, the eccentric slider is connected to the second shaft segment, the eccentric slider is provided with a sliding rod, which is adapted to the slide groove on the slider, the slider is connected to one end of the power pull rod, and the other end of the power pull rod is connected to the wind tunnel attitude control system.

[0012] As a further solution of the present invention: the nose is made of lightweight and high-strength composite materials, and a number of reinforcement frames are set in the nose. A connecting frame is designed on the rear end face of the nose and is connected to the front end of the middle fuselage through a circular straight opening.

[0013] As a further solution of the present invention: the front part of the mid-fuselage is connected to the nose, the rear part is connected to the rear fuselage and the tail, the upper part is connected to the wing, and the middle part is connected to the balance. The skin is made of lightweight high-strength composite materials, and the frame is made of lightweight high-strength composite materials or lightweight alloy materials. A connection reference plane is provided to connect with the balance. The frame includes an upper connecting plate of the mid-fuselage frame, a left connecting plate of the mid-fuselage frame, and a right connecting plate of the mid-fuselage frame. The upper surface of the middle fuselage frame upper connecting plate is designed with a wing mounting reference surface and is connected to the wing by screws. The front and rear end surfaces of the middle fuselage frame upper connecting plate are connected to the middle fuselage front connecting frame and the middle fuselage rear connecting frame by screws. The side surfaces of the middle fuselage frame left connecting plate and the middle fuselage frame right connecting plate are connected to the middle fuselage frame upper connecting plate by screws. The front and rear end surfaces are connected to the middle fuselage front connecting frame and the middle fuselage rear connecting frame by screws. The left and right end surfaces of the balance connection frame are connected to the left and right connection plates of the middle fuselage frame by screws, the upper surface is connected to the upper connection plate of the middle fuselage frame by screws, and the lower surface is connected to the balance by screws; A reasonable gap is maintained between the frame and the wind tunnel struts to prevent collision during movement.

[0014] As a further solution of the present invention: the rear fuselage is made of lightweight and high-strength composite materials, a front connecting frame is designed on the front end surface, which is connected to the middle fuselage through a circular straight opening, and a rear fuselage reinforcement rod is arranged inside. The front end of the rear fuselage reinforcement rod is connected to the front connecting frame of the rear fuselage, and the rear end is connected to the front beam of the vertical tail.

[0015] As a further embodiment of the present invention, the wing is made of lightweight, high-strength composite materials and adopts a beam, rib and skin structure. The beams are arranged at appropriate positions in the chord direction of the wing and arranged along the span direction of the aircraft. The material, size and number of the beams are selected according to the load of the aircraft and the planform of the wing. The ribs are arranged along the chord direction of the aircraft wing to provide a connection base for components that need to be connected to the wing main wing surface. The central wing is designed with a connection plane, which is connected to the mid-fuselage through a connector. The tail is made of lightweight and high-strength composite materials, and adopts a beam, rib and skin structure. Beams are set at appropriate positions in the chord direction of the vertical tail and the horizontal tail. The material, size and number of the beams are selected according to the load level and the plane shape of the tail. The tail is connected to the rear fuselage through connecting parts or is made into an integral whole with the rear fuselage.

[0016] In a second aspect, the present invention provides a test method for a dynamic derivative wind tunnel test, comprising the following steps: Assemble the nose, mid-fuselage, rear fuselage, balance, wings and tail into an aircraft model; Assemble the yaw oscillation mechanism and install the aircraft model on the yaw oscillation mechanism to conduct heave, side shift, and yaw oscillation tests; After completing all tests under this oscillation mode, dismantle the aircraft model and remove the yaw oscillation mechanism; Assemble the pitch oscillation mechanism and install the aircraft model on the pitch oscillation mechanism to conduct a pitch oscillation test; After completing all tests under the pitch oscillation mode, dismantle the aircraft model and remove the pitch oscillation mechanism; Assemble the roll oscillation mechanism and install the aircraft model on the roll oscillation mechanism to conduct a roll oscillation test; After completing all tests under the rolling oscillation mode, the dynamic derivatives of the aircraft in each vibration mode are obtained through processing and calculation, and the data are confirmed to be accurate; The aircraft model and rolling oscillation mechanism were dismantled and packed as required to complete the test.

[0017] The beneficial effects of this application are: 1. The rotation center of the model of the present application can be placed near the center of gravity of the model. When the model performs oscillatory motion during the test, the displacement of the model can be reduced, thereby increasing the size of the model and improving the Reynolds number of the test, thereby improving the measurement accuracy of the dynamic derivative.

[0018] 2. This application can realize model heave, side shift, yaw, pitch and roll oscillation by replacing adapters, and only requires three adapters. The test model installation and test state conversion are simple, which can effectively improve the test efficiency of dynamic derivative wind tunnel tests.

[0019] 3. The wings, tail and fuselage of the model of this application are designed with lightweight and high-strength composite materials, and reinforced connection devices are added at key parts, which can effectively reduce the weight of the model, improve the stiffness of the model, reduce the impact of weak model stiffness on the accuracy of dynamic derivative measurement, and obtain more accurate dynamic derivative data.

[0020] The present application is described in further detail below with reference to the accompanying drawings of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The figure is a schematic diagram of a test device for dynamic derivative wind tunnel test; Figure 2 It is a partial side view of the device of the mid-fuselage balance and wind tunnel support rod; Figure 3 It is an axonometric view of the installation part of the mid-fuselage balance and wind tunnel support rod; Figure 4 Schematic diagram of the test device capable of achieving heave, sideways and yaw oscillations; Figure 5 Schematic diagram of the test device that can achieve pitch oscillation; Figure 6 Schematic diagram of the test device that can achieve rolling oscillation; Figure 7 Schematic diagram of the rolling oscillating Libra.

[0022] Explanation of the numbers in the figure: 1. Nose; 2. Wing; 3. Tail; 4. Wind tunnel support rod; 5. Mid-fuselage; 6. Rear fuselage; 7. Balance; 8. Front connecting frame of mid-fuselage; 9. Balance connecting frame; 10. Pitch oscillation balance seat; 11. Pitch oscillation base; 12. Power pull rod; 13. Rear connecting frame of mid-fuselage; 14. Rear fuselage reinforcement rod; 15. Front beam of vertical tail; 16. Right connecting plate of mid-fuselage frame; 17. Left connecting plate of mid-fuselage frame; 18. Upper connecting plate of mid-fuselage frame; 19. Yaw oscillation balance seat; 20. Roll oscillation balance seat; 21. Slider; 22. Eccentric slider; 23. Roll oscillation base. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention will be described in more detail below with reference to the accompanying drawings in the embodiments of the present invention.

[0024] In the drawings, the same or similar reference numerals throughout the drawings represent the same or similar elements or elements having the same or similar functions. The described embodiments are only some of the embodiments of the present invention, but not all of the embodiments.

[0025] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0026] The following is combined with Figure 1-7 The embodiments of the present invention are described in detail.

[0027] Example 1 The present invention provides a test device for a dynamic derivative wind tunnel test, comprising: The aircraft model is assembled from a nose 1, a middle fuselage 5, a rear fuselage 6, a balance 7, wings 2 and a tail 3; an oscillating mechanism having an adapter connected to a balance 7; The wind tunnel support rod 4 has one end connected to the wind tunnel attitude control system and the other end connected to the oscillation mechanism.

[0028] Furthermore, the oscillation mechanism includes a yaw oscillation mechanism, a pitch oscillation mechanism and a roll oscillation mechanism. By designing and replacing three adapters, the heave, side shift, yaw, pitch and roll oscillations of the aircraft model can be achieved.

[0029] Furthermore, the adapter of the yaw oscillation mechanism is a yaw oscillation balance seat 19, and the yaw oscillation balance seat 19 has a first mounting part and a second mounting part. The first mounting part is designed to be in the shape of a "dustpan", and the balance 7 is fixedly connected to the first mounting part. The second mounting part has a flat connecting surface and is fixedly connected to the upper end of the wind tunnel support rod 4.

[0030] Furthermore, the pitch oscillation mechanism also includes a pitch oscillation base 11 and a power pull rod 12, and its adapter is a pitch oscillation balance seat 10. The pitch oscillation balance seat 10 has a third mounting part and a fourth mounting part. The third mounting part is designed to be in the shape of a "dustpan", and the balance 7 is fixedly connected to the third mounting part. The pitch oscillation base 11 has a flat connecting surface, which is fixedly connected to the upper end of the wind tunnel support rod 4, and connecting ears are provided on both sides. One end of the fourth mounting part close to the third mounting part is hinged to the pitch oscillation base 11, and the other end is hinged to one end of the power pull rod 12. The other end of the power pull rod 12 is connected to the wind tunnel attitude control system.

[0031] Furthermore, the roll oscillation mechanism also includes a roll oscillation base 23, an eccentric slider 22, a slider 21 and a power pull rod 12, and its adapter is a roll oscillation balance seat 20. The roll oscillation balance seat 20 has a fifth mounting part and a sixth mounting part. The fifth mounting part is designed to be in the shape of a "dustpan". The balance 7 is fixedly connected to the fifth mounting part. The sixth mounting part is designed to be in the shape of an eccentric shaft, which includes a first shaft segment and a second shaft segment, which are not coaxial. The roll oscillation base 23 has a flat connecting surface, which is fixedly connected to the upper end of the wind tunnel support rod 4. The roll oscillation base 23 is hinged to the first shaft segment, and the eccentric slider 22 is connected to the second shaft segment. A sliding rod is provided on the eccentric slider 22, which is adapted to the slide groove on the slider 21. The slider 21 is connected to one end of the power pull rod 12, and the other end of the power pull rod 12 is connected to the wind tunnel attitude control system.

[0032] Specifically, a slide rail is mounted on the wind tunnel support rod 4, and a slider 21 (using a claw-type design) cooperates with the rail. A power pull rod 12 is hingedly connected to the lower end of the slider 21. A plug with an inclined slot is located on the upper end of the slider 21. An eccentric slider 22 has a through-hole that interference fits with the second shaft segment. The eccentric slider 22 also has a slot, within which a slide rod (the slide rod and the through-hole are not vertically aligned) is located, which fits within the slot of the slider 21. When the power pull rod 12 drives the slider 21 up and down, it pushes the eccentric slider 22 to swing up and down and left and right, causing the roll oscillation balance 20 to generate a roll motion, thereby generating roll oscillations in the aircraft model.

[0033] Furthermore, the nose 1 is made of lightweight and high-strength composite materials, and a number of reinforcement frames are set inside the nose 1. A connecting frame is designed on the rear end face of the nose 1 and is connected to the front end of the middle fuselage 5 through a circular straight opening.

[0034] Furthermore, the front of the middle fuselage 5 is connected to the nose 1, the rear is connected to the rear fuselage 6 and the tail 3, the upper part is connected to the wing 2, and the middle part is connected to the balance 7. Its skin is made of lightweight high-strength composite materials, and the frame is made of lightweight high-strength composite materials or lightweight alloy materials. A connection reference plane is set at an appropriate position to connect with the balance 7. The frame includes an upper connecting plate 18 of the middle fuselage frame, a left connecting plate 17 of the middle fuselage frame, and a right connecting plate 16 of the middle fuselage frame. The design of the frame must ensure that there is no reasonable gap between the frame and the wind tunnel support rod 4 at any position, and no collision will occur during movement; The upper surface of the middle fuselage frame upper connecting plate 18 is designed as the wing 2 mounting reference surface and is connected to the wing 2 by screws. The front and rear end surfaces of the middle fuselage frame upper connecting plate 18 are connected to the middle fuselage front connecting frame 8 and the middle fuselage rear connecting frame 13 by screws. The side surfaces of the middle fuselage frame left connecting plate 17 and the middle fuselage frame right connecting plate 16 are connected to the middle fuselage frame upper connecting plate 18 by screws. The front and rear end surfaces are connected to the middle fuselage front connecting frame 8 and the middle fuselage rear connecting frame 13 by screws. The left and right end surfaces of the balance connecting frame 9 are connected to the left and right connecting plates of the middle fuselage frame by screws, the upper surface is connected to the upper connecting plate 18 of the middle fuselage frame by screws, and the lower surface is connected to the balance 7 by screws; A reasonable gap is maintained between the frame and the wind tunnel support rod 4 so that no collision occurs during movement.

[0035] Furthermore, the rear fuselage 6 is made of lightweight and high-strength composite materials, and a front connecting frame is designed on the front end surface, which is connected to the middle fuselage 5 through a circular straight opening. A rear fuselage reinforcement rod 14 is arranged inside, and the front end of the rear fuselage reinforcement rod 14 is connected to the front connecting frame of the rear fuselage 6, and the rear end is connected to the vertical tail front beam 15.

[0036] Furthermore, the wing 2 is made of lightweight, high-strength composite materials and adopts a beam, rib and skin structure. Beams are set at appropriate positions in the chord direction of the wing 2 and arranged along the span direction of the aircraft. The material, size and number of the beams are selected according to the load of the aircraft and the planar shape of the wing 2. Ribs are arranged along the chord direction of the aircraft wing 2 to provide a connection base for components that need to be connected to the main wing surface of the wing 2. The central wing is designed with a connection plane, which is connected to the mid-fuselage 5 through a connector. The tail 3 is made of lightweight and high-strength composite materials, and adopts a beam, rib and skin structure. Beams are set at appropriate positions in the chord direction of the vertical tail and the horizontal tail. The material, size and number of the beams are selected according to the load level and the plane shape of the tail 3. The tail 3 is connected to the rear fuselage 6 through a connecting piece or is made into a whole with the rear fuselage 6.

[0037] Furthermore, the wind tunnel support rod 4 connects the model balance 7 and the wind tunnel attitude control system. It is made of metal material and one end is connected to the balance 7 through an adapter. By replacing different adapters, the rotation center of the adapter can be placed in a suitable position as needed to achieve model heave, side shift, yaw, pitch and roll oscillations.

[0038] Example 2 See also Figure 1 、 Figure 2 , body 3, Figure 4 、 Figure 5 and Figure 6 As shown, the present invention provides a test device for dynamic derivative wind tunnel test, which includes: a nose 1, a middle fuselage 5, a rear fuselage 6, a tail 3, a balance 7, a balance seat, a wind tunnel support rod 4, etc.

[0039] As a preferred solution, the skin of the nose 1 is made of carbon fiber, and the thickness of the skin is maintained between 1 mm and 2 mm. The reinforcement frame inside the nose 1 is made of carbon fiber plate. A connecting frame is designed on the rear end face of the nose 1, which is made of aluminum alloy and connected to the front end of the middle fuselage 5 through a circular straight mouth, positioned by pins and connected by screws.

[0040] As a preferred solution, the middle fuselage 5 is covered with carbon fiber, with a thickness of 1 to 2 mm. In the front-end design, the front fuselage connecting frame 8 is connected to the nose 1 through a round straight opening, positioned by pins and fixed with screws. In the rear-end design, the rear fuselage connecting frame 13 is connected to the rear fuselage 6 through a round straight opening, positioned by pins and fixed with screws.

[0041] The middle fuselage 5 frame includes an upper connecting plate 18, a left connecting plate 17, and a right connecting plate 16. As a preferred solution, aluminum alloy is used to ensure good processability of the parts and minimize their weight. The upper surface of the upper connecting plate 18 is designed as a wing 2 mounting reference surface and is connected to the wing 2 by screws. The front and rear end surfaces of the upper connecting plate 18 are connected to the front connecting frame 8 and the rear connecting frame 13 of the middle fuselage by screws. The sides of the left connecting plate 17 and the right connecting plate 16 of the middle fuselage are connected to the upper connecting plate 18 of the middle fuselage frame by screws, and the front and rear end surfaces are connected to the front connecting frame 8 and the rear connecting frame 13 of the middle fuselage by screws. The balance connecting frame 9 is made of aluminum alloy, and its left and right end surfaces are connected to the left and right connecting plates of the middle fuselage frame by screws. The upper surface is connected to the upper connecting plate 18 of the middle fuselage frame by screws, and the lower surface is connected to the balance 7 by screws.

[0042] Wing 2's skin is made of carbon fiber, with forward and aft spars made of carbon fiber plates. Ribs are located where they connect to the flaps and engine nacelles, also made of carbon fiber plates. The flaps and engine nacelles are screwed to the ribs of Wing 2. The center wing is made of aluminum alloy, with its left and right sides connected to the left and right outer wings using carbon fiber plates and screws. The underside of the center wing is screwed to the connecting plate 18 on the center fuselage frame.

[0043] The skin of the rear fuselage 6 and the tail 3 is formed of carbon fiber, and a front connecting frame is designed on the front end surface. It is connected to the middle fuselage 5 through a round straight mouth and fixed with pin positioning screws. In order to improve the rigidity of the tail 3 during the oscillating movement, a rear fuselage reinforcement rod 14 is provided. The front end of the rear fuselage reinforcement rod 14 is connected to the front connecting frame of the rear fuselage, and the rear end is connected to the vertical tail front beam 15. The rear fuselage reinforcement rod 14 is made of carbon rod. The vertical tail skin is made of carbon fiber, and a front beam and a rear beam are provided. Two ribs are provided from bottom to top. The horizontal tail skin is made of carbon fiber. The horizontal tail has a smaller load, and a wing beam is provided, which is connected to the vertical tail front beam 15. The horizontal tail, vertical tail and rear fuselage 6 are formed into one piece to form a whole, thereby improving the rigidity of the tail 3 and the rear fuselage 6, thereby improving the measurement accuracy of each dynamic derivative.

[0044] The wind tunnel struts 4 and the balance are key components connecting the model to the wind tunnel model attitude control mechanism. They require very high strength and rigidity and are therefore made of high-strength steel. One end of the wind tunnel struts 4 is connected to the wind tunnel model attitude control system, while the other end is connected to the balance or base via screws. To achieve five oscillation modes, including heave, lateral shift, pitch, yaw, and roll, three types of balances are designed. The yaw oscillation balance 19 is capable of achieving the model's yaw, heave, and lateral shift oscillations; the pitch oscillation balance 10 is capable of achieving the model's pitch oscillations; and the roll oscillation balance 20 is capable of achieving the model's roll oscillations.

[0045] The front part of the yaw oscillation balance seat 19 is designed to connect to the plane of the balance 7, and is connected to the lower surface of the balance 7 by screws. The rear part is connected to the wind tunnel support rod 4 by screws. Through the wind tunnel model attitude control mechanism, the wind tunnel support rod 4 produces up and down, left and right and rotational movements, thereby realizing the heave, side shift and yaw oscillation of the model.

[0046] The pitch oscillation balance seat 10, the pitch oscillation base 11 and the power pull rod 12 together constitute the pitch oscillation mechanism. The three parts are all made of high-strength steel. A plane connecting the balance 7 is designed at the front of the pitch oscillation balance seat 10, which is connected to the lower surface of the balance 7 by screws. The middle part is connected to the pitch oscillation base 11 by a pin and a bearing, and the rear part is connected to the power pull rod 12 by a pin and a bearing. The upper part of the pitch oscillation base 11 is connected to the pitch oscillation balance seat 10 by a pin and a bearing, and the lower part is connected to the wind tunnel support rod 4 by screws. The upper part of the power pull rod 12 is connected to the rear part of the pitch oscillation balance seat 10 by a pin and a bearing, and the lower part is connected to the wind tunnel attitude control system. Under the drive of the wind tunnel attitude control system, the power pull rod 12 can generate up and down movement, thereby causing the pitch balance support to generate rotational motion around the pin of the pitch oscillation base 11, causing the aircraft model to generate pitch oscillation, and then the dynamic derivative of the aircraft in this oscillation mode can be measured.

[0047] The roll oscillation balance seat 20, roll oscillation base 23, eccentric slider 22, slider 21, and power pull rod 12 together constitute a roll oscillation mechanism, which is made of high-strength steel. The front part of the roll oscillation balance seat 20 is designed with a plane connected to the balance 7, which is connected to the lower surface of the balance 7 by screws. The middle part is designed to be cylindrical and can rotate around the center of the roll oscillation base 23. A cylinder is designed at the rear, which is not coaxial with the cylinder in the middle. By changing the eccentricity, the amplitude of the roll oscillation can be adjusted. It is connected to the eccentric slider 22, and the lower part of the eccentric slider 22 is connected to the slider 21. The lower part of the slider 21 is connected to the power pull rod 12. The power pull rod 12 can move up and down under the drive of the wind tunnel attitude control system, causing the slider 21 to slide up and down, driving the eccentric slider 22 to slide up and down and left and right, causing the roll oscillation balance seat 20 to generate a roll motion, thereby causing the aircraft model to generate a roll oscillation, and then the dynamic derivative of the aircraft in this oscillation mode can be measured.

[0048] During the dynamic derivative wind tunnel test, the model is generally assembled and debugged first, the yaw oscillation mechanism is installed, and heave, sideways, and yaw oscillation tests are carried out. After completing all tests under the oscillation mode, the yaw oscillation mechanism is removed, the pitch oscillation mechanism is installed, and the pitch oscillation test is carried out. After completing all tests under the pitch oscillation mode, the pitch oscillation mechanism is removed, the roll oscillation mechanism is installed, and the roll oscillation test is carried out. After completing all tests under the roll oscillation mode, the dynamic derivatives of the aircraft in each vibration mode are obtained through processing and calculation, and the data is confirmed to be accurate. The wind tunnel test model is removed, packed as required, and the test is ended.

[0049] Example 3 The present invention provides a test method for a dynamic derivative wind tunnel test, which comprises the following steps: Assemble the nose, mid-fuselage, rear fuselage, balance, wings and tail into an aircraft model; Assemble the yaw oscillation mechanism and install the aircraft model on the yaw oscillation mechanism to conduct heave, side shift, and yaw oscillation tests; After completing all tests under this oscillation mode, dismantle the aircraft model and remove the yaw oscillation mechanism; Assemble the pitch oscillation mechanism and install the aircraft model on the pitch oscillation mechanism to conduct a pitch oscillation test; After completing all tests under the pitch oscillation mode, dismantle the aircraft model and remove the pitch oscillation mechanism; Assemble the roll oscillation mechanism and install the aircraft model on the roll oscillation mechanism to conduct a roll oscillation test; After completing all tests under the rolling oscillation mode, the dynamic derivatives of the aircraft in each vibration mode are obtained through processing and calculation, and the data are confirmed to be accurate; The aircraft model and rolling oscillation mechanism were dismantled and packed as required to complete the test.

[0050] So far, the purpose of the present invention has been accomplished.

[0051] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A test device for dynamic derivative wind tunnel testing, characterized in that: include: An aircraft model, which is assembled from a nose, mid-fuselage, rear fuselage, balance, wings, and tail; an oscillating mechanism having an adapter connected to a balance; The wind tunnel support rod has one end connected to the wind tunnel attitude control system and the other end connected to the oscillation mechanism.

2. The test device for dynamic derivative wind tunnel test according to claim 1, characterized in that: The oscillation mechanism includes a yaw oscillation mechanism, a pitch oscillation mechanism and a roll oscillation mechanism. By designing and replacing three adapters, the heave, side shift, yaw, pitch and roll oscillations of the aircraft model can be achieved.

3. The test device for dynamic derivative wind tunnel test according to claim 2, characterized in that: The adapter of the yaw oscillation mechanism is a yaw oscillation balance seat, which has a first mounting part and a second mounting part. The first mounting part is designed to be in the shape of a "dustpan", and the balance is fixedly connected to the first mounting part. The second mounting part has a flat connecting surface and is fixedly connected to the upper end of the wind tunnel support rod.

4. The test device for dynamic derivative wind tunnel test according to claim 2, characterized in that: The pitch oscillation mechanism also includes a pitch oscillation base and a power pull rod, and its adapter is a pitch oscillation balance seat. The pitch oscillation balance seat has a third mounting part and a fourth mounting part. The third mounting part is designed to be in the shape of a "dustpan". The balance is fixedly connected to the third mounting part. The pitch oscillation base has a flat connecting surface, which is fixedly connected to the upper end of the wind tunnel support rod, and connecting ears are provided on both sides. One end of the fourth mounting part close to the third mounting part is hinged to the pitch oscillation base, and the other end is hinged to one end of the power pull rod. The other end of the power pull rod is connected to the wind tunnel attitude control system.

5. The test device for dynamic derivative wind tunnel test according to claim 2, characterized in that: The roll oscillation mechanism also includes a roll oscillation base, an eccentric slider, a slider and a power pull rod, and its adapter is a roll oscillation balance seat. The roll oscillation balance seat has a fifth mounting part and a sixth mounting part. The fifth mounting part is designed to be in the shape of a "dustpan". The balance is fixedly connected to the fifth mounting part. The sixth mounting part is designed to be in the shape of an eccentric shaft, which includes a first shaft segment and a second shaft segment, which are not coaxial. The roll oscillation base has a flat connecting surface, which is fixedly connected to the upper end of the wind tunnel support rod. The roll oscillation base is hinged to the first shaft segment, and the eccentric slider is connected to the second shaft segment. A sliding rod is provided on the eccentric slider, which is adapted to the slide groove on the slider. The slider is connected to one end of the power pull rod, and the other end of the power pull rod is connected to the wind tunnel attitude control system.

6. The test device for dynamic derivative wind tunnel test according to any one of claims 3 to 5, characterized in that: The nose is made of lightweight and high-strength composite materials, and a number of reinforcement frames are arranged inside the nose. A connecting frame is designed on the rear end face of the nose and is connected to the front end of the middle fuselage through a circular straight opening.

7. The test device for dynamic derivative wind tunnel test according to claim 6, characterized in that: The front part of the mid-fuselage is connected to the nose, the rear part is connected to the rear fuselage and the tail, the upper part is connected to the wing, and the middle part is connected to the balance. The skin is made of lightweight high-strength composite materials, and the frame is made of lightweight high-strength composite materials or lightweight alloy materials. A connection reference plane is set to connect with the balance. The frame includes an upper connecting plate of the mid-fuselage frame, a left connecting plate of the mid-fuselage frame, and a right connecting plate of the mid-fuselage frame; The upper surface of the middle fuselage frame upper connecting plate is designed with a wing mounting reference surface and is connected to the wing by screws. The front and rear end surfaces of the middle fuselage frame upper connecting plate are connected to the middle fuselage front connecting frame and the middle fuselage rear connecting frame by screws. The side surfaces of the middle fuselage frame left connecting plate and the middle fuselage frame right connecting plate are connected to the middle fuselage frame upper connecting plate by screws. The front and rear end surfaces are connected to the middle fuselage front connecting frame and the middle fuselage rear connecting frame by screws. The left and right end surfaces of the balance connection frame are connected to the left and right connection plates of the middle fuselage frame by screws, the upper surface is connected to the upper connection plate of the middle fuselage frame by screws, and the lower surface is connected to the balance by screws; A reasonable gap is maintained between the frame and the wind tunnel struts to prevent collision during movement.

8. The test device for dynamic derivative wind tunnel test according to claim 7, characterized in that: The rear fuselage is made of lightweight and high-strength composite materials. A front connecting frame is designed on the front end surface and is connected to the middle fuselage through a circular straight opening. A rear fuselage reinforcement rod is arranged inside. The front end of the rear fuselage reinforcement rod is connected to the front connecting frame of the rear fuselage, and the rear end is connected to the front beam of the vertical tail.

9. The test device for dynamic derivative wind tunnel test according to claim 8, characterized in that: The wing is made of lightweight, high-strength composite materials and adopts a beam, rib and skin structure. The beams are set at appropriate positions in the chord direction of the wing and arranged along the span direction of the aircraft. The material, size and number of the beams are selected according to the load of the aircraft and the plane shape of the wing; The ribs are arranged along the chord direction of the aircraft wing to provide a connection base for the components that need to be connected to the main wing surface; the central wing is designed with a connecting plane, which is connected to the mid-fuselage through a connector; The tail is made of lightweight and high-strength composite materials, and adopts a beam, rib and skin structure. Beams are set at appropriate positions in the chord direction of the vertical tail and the horizontal tail. The material, size and number of the beams are selected according to the load level and the plane shape of the tail. The tail is connected to the rear fuselage through connecting parts or is made into an integral whole with the rear fuselage.

10. A test method for dynamic derivative wind tunnel testing, characterized in that: The following steps are involved: Assemble the nose, mid-fuselage, rear fuselage, balance, wings and tail into an aircraft model; Assemble the yaw oscillation mechanism and install the aircraft model on the yaw oscillation mechanism to conduct heave, side shift, and yaw oscillation tests; After completing all tests under this oscillation mode, dismantle the aircraft model and remove the yaw oscillation mechanism; Assemble the pitch oscillation mechanism and install the aircraft model on the pitch oscillation mechanism to conduct a pitch oscillation test; After completing all tests under the pitch oscillation mode, dismantle the aircraft model and remove the pitch oscillation mechanism; Assemble the roll oscillation mechanism and install the aircraft model on the roll oscillation mechanism to conduct a roll oscillation test; After completing all tests under the rolling oscillation mode, the dynamic derivatives of the aircraft in each vibration mode are obtained through processing and calculation, and the data are confirmed to be accurate; The aircraft model and rolling oscillation mechanism were dismantled and packed as required to complete the test.

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