Ground simulation method and device for aerodynamic characteristic test of real helicopter

Abstract

The invention discloses a real helicopter aerodynamic characteristic test ground simulation method and device, and relates to the helicopter wind tunnel test field, and the device comprises a pedestal arranged on the ground, the pedestal is provided with a rotating disc, the rotating disc is provided with a balance mechanism, and the balance mechanism is provided with a three-point supported web support type mechanism; the real helicopter can be mounted on the belly support type mechanism; the strain bridges are arranged on the main transmission shaft and the tail transmission shaft. A real helicopter is installed on a full-size wind tunnel test section, and the aerodynamic performance of the helicopter is measured by adopting a balance mechanism and a strain bridge; according to the method, the aerodynamic performance assessment test is carried out under the working conditions of the rotor, the tail rotor and the whole helicopter, and on the basis, the aerodynamic performance income data of the helicopter are obtained through the optimization of the whole-helicopter aerodynamic layout, so that a basis is provided for the comprehensive optimization design of the whole-helicopter aerodynamic layout in model development.

Description

Technical Field

[0001] The invention relates to the field of helicopter wind tunnel tests, in particular to a ground simulation method and device for a real helicopter aerodynamic characteristic test. Background Art

[0002] Helicopters have complex unsteady aerodynamic and structural coupling characteristics. Given the complexity of multidisciplinary coupling and the dangerousness of the flight test boundary, multidisciplinary problems dominated by aerodynamic / dynamic / structural coupling are often exposed.

[0003] At present, helicopter aerodynamic characteristics tests are often conducted using helicopter scaled model wind tunnel tests. For example, Chinese patent publication number "CN116558766A" discloses "A ground simulation method for testing tail rotor aerodynamic characteristics in an aerodynamic disturbance environment", and Chinese patent publication number "CN116735144A" discloses "A ground simulation method for testing helicopter side-flight aerodynamic characteristics". These technical solutions have a series of problems such as unclear understanding of aerodynamic mechanisms and incomplete verification during the helicopter development process or actual use due to local distortion of the model.

[0004] To this end, it is conceivable to conduct real helicopter tests in full-scale wind tunnels to solve key technical problems such as the comprehensive optimization design of the helicopter rotor / fuselage / wing / tail rotor aerodynamic layout; at present, the full-scale test of the helicopter can only be carried out on a certain component of the helicopter, such as the Chinese patent with publication number "CN118168760B" discloses "A full-size tail rotor aerodynamic performance test evaluation method", which is a test for the tail rotor; another example is the Chinese patent with publication number "CN114001919A" discloses "A full-size tilt-rotor axial flow forward flight performance test ground simulation method", which is mainly used for testing the rotor; the rest of the Chinese patents such as "CN117740307B", "CN116561488B", and "CN117740307A" are all for testing the rotor.

[0005] Therefore, in order to obtain the most realistic data, solve key technical problems such as the comprehensive optimization design of helicopter rotor / fuselage / wing / tail rotor aerodynamic layout, and avoid local distortion caused by model scaling, a new test simulation technology needs to be proposed in this field. Summary of the invention

[0006] The purpose of the present invention is to provide a ground simulation method and device for aerodynamic characteristics test of a real helicopter in response to the above-mentioned problems, install the real helicopter in a full-size wind tunnel test section, and use a balance mechanism and a strain bridge to measure the aerodynamic performance of the helicopter; establish a method for conducting aerodynamic performance assessment tests under rotor, tail rotor and full-machine working conditions, and on this basis, obtain helicopter aerodynamic performance benefit data through optimization of the full-machine aerodynamic layout, so as to provide a basis for the comprehensive optimization design of the full-machine aerodynamic layout in model development.

[0007] The technical solution adopted by the present invention is as follows: A ground simulation method for a real helicopter aerodynamic characteristics test comprises the following steps: S1: In the full-scale wind tunnel test section, the real helicopter is directly or indirectly mounted on the balance mechanism; S2: Install strain bridges on the main drive shaft and tail drive shaft of the entire helicopter; S3: Start the wind tunnel to carry out aerodynamic characteristics test of the real helicopter; specifically comprising steps S31- S34; S31: Remove the tail rotor blades and conduct rotor aerodynamic performance assessment tests; S32: Remove the rotor blades and conduct aerodynamic performance test of the tail rotor; S33: Conduct aerodynamic performance assessment tests of helicopters under full aircraft operating conditions; S34: Conduct aerodynamic performance benefit verification tests under full helicopter operating conditions.

[0008] Furthermore, in step S31, the specific process of the rotor aerodynamic performance assessment test is as follows: The hovering test is carried out at the rotor operating speed and different total pitches; the forward flight test is carried out at the rotor operating speed and different incoming flow velocities by adjusting the rotor main shaft inclination angle so that the vertical force of the balance mechanism reaches a given value and the horizontal force is zero, thereby obtaining the aerodynamic force and torque data of the rotor in different states. In this state, the tail rotor hub rotates at its operating speed.

[0009] Further, in step S32, the specific process of the tail rotor aerodynamic performance assessment test is as follows: Both the hover test and the forward flight test are carried out at different collective pitches at the tail rotor operating speed to obtain the aerodynamic force and torque data of the tail rotor at different incoming flow velocities. In this state, the rotor hub rotates at its operating speed.

[0010] Further, in step S33, the specific process of the aerodynamic performance assessment test under the full helicopter working condition is as follows: Under the operating speed of the rotor and tail rotor, the real flight condition of the helicopter is simulated. The rotor and tail rotor are manipulated under different incoming flow velocities to make the vertical force of the balance reach a given value, and the horizontal force, lateral force, yaw moment, roll moment, and pitch moment tend to zero, so as to obtain the rotor and tail rotor torque data under different working conditions.

[0011] Further, in step S34, the specific process of the aerodynamic performance assessment test under the full helicopter working condition is as follows: By installing fuselage guide vanes, side strips and other layout optimization measures, step S33 is repeated to obtain helicopter aerodynamic performance benefit data.

[0012] Furthermore, in step S1, the real helicopter is installed on the balance mechanism using a three-point supported belly-supported mechanism, and the belly-supported mechanism has stiffness and damping adjustment functions.

[0013] Furthermore, the tail strut of the belly-supporting mechanism has a vertical stroke to achieve a change in the inclination angle of the rotor main shaft.

[0014] Furthermore, the balance mechanism is mounted on a turntable, and the turntable is mounted on a base on the floor of the wind tunnel.

[0015] Furthermore, in step S3, the helicopter cockpit control system is modified and operated and controlled in the ground control room during the test.

[0016] A ground simulation device for aerodynamic characteristic test of a real helicopter comprises a base installed on the ground, a turntable is installed on the base, a balance mechanism is arranged on the turntable, a belly-braced mechanism with three-point support is arranged on the balance mechanism, and the real helicopter can be installed on the belly-braced mechanism; and the device also comprises a strain bridge arranged on the main transmission shaft and the tail transmission shaft.

[0017] Furthermore, the tail support rod of the belly-supporting mechanism is supported on the tail of the actual helicopter, and the tail support rod is a telescopic rod having a vertical stroke.

[0018] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: The present invention conducts actual helicopter tests in a full-scale wind tunnel, installs a real helicopter in a test section of the full-scale wind tunnel, and uses a balance mechanism and a strain bridge to measure the aerodynamic performance of the helicopter; establishes a method for conducting aerodynamic performance assessment tests under rotor, tail rotor and full-machine working conditions, and realizes the ability to assess the aerodynamic performance of the helicopter and verify the aerodynamic performance benefits after the aerodynamic layout is optimized; on this basis, the aerodynamic performance benefit data of the helicopter is obtained through the optimization of the aerodynamic layout of the whole aircraft, and the comprehensive optimization design problem of the aerodynamic layout of the whole aircraft in the development of the helicopter is solved, and local distortion caused by model reduction is avoided, which will greatly improve the development process of my country's helicopters, reduce the development risk, shorten the development cycle, and provide more powerful technical support for the development of helicopter models. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a schematic diagram of the present invention when the inclination angle of the rotor main shaft is 0°; Figure 3 It is a schematic diagram when the inclination angle of the rotor main shaft in the present invention is not 0°; Markings in the figure: 1-belly support mechanism; 2-balance mechanism; 3-turntable; 4-tail support rod; 5-base; 6-real helicopter. DETAILED DESCRIPTION

[0020] In the description of this specification, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or is the orientation or position relationship in which the product of this specification is usually placed when used. It is only for the convenience of describing this specification and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this specification.

[0021] In addition, if the terms "horizontal" or "vertical" appear in the description of this specification, it does not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0022] In the description of this specification, it should also be noted that, unless otherwise clearly stipulated and limited, the terms "set", "installed", "connected" and "connected" should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be a connection between the internal parts of two elements.

[0023] Example 1 like Figure 1-Figure 3 As shown, a ground simulation method for a real helicopter aerodynamic characteristics test comprises the following steps: S1: In the full-scale wind tunnel test section, the real helicopter 6 is directly or indirectly mounted on the balance mechanism 2, and the vertical aerodynamic force of the helicopter is obtained through the balance mechanism 2.

[0024] S2: Install strain bridges on the main drive shaft and tail drive shaft of the entire helicopter. The torque of the rotor is obtained through the strain bridge on the main drive shaft, and the torque of the tail rotor is obtained through the strain bridge on the tail drive shaft.

[0025] S3: starting the wind tunnel to conduct aerodynamic characteristic test of the real helicopter 6; specifically including steps S31 to S34.

[0026] S31: Remove the tail rotor blades and conduct aerodynamic performance assessment tests on the rotor; specifically, the hover test is conducted at the rotor operating speed and with different total pitches given; the forward flight test is conducted at the rotor operating speed and with different incoming flow velocities by adjusting the rotor main shaft inclination angle so that the vertical force of the balance mechanism 2 reaches a given value and the horizontal force is zero, thereby obtaining the aerodynamic force and torque data of the rotor in different states. In this state, the tail rotor hub rotates at its operating speed.

[0027] S32: Remove the rotor blades and conduct aerodynamic performance assessment test of the tail rotor; the hover test and forward flight test are both carried out at different total pitches at the tail rotor operating speed to obtain the aerodynamic force and torque data of the tail rotor at different incoming flow velocities. In this state, the rotor hub rotates at its operating speed.

[0028] S33: Conduct aerodynamic performance assessment tests under full helicopter operating conditions; simulate the actual flight conditions of the helicopter at the operating speeds of the rotor and tail rotor, and use different incoming flow velocities to manipulate the rotor and tail rotor so that the vertical force of the balance reaches a given value, and the horizontal force, lateral force, yaw moment, roll moment, and pitch moment tend to zero, to obtain the rotor and tail rotor torque data under different operating conditions.

[0029] S34: Conduct aerodynamic performance benefit verification test under full helicopter operating conditions; repeat step S33 by installing fuselage guide vanes, side strips and other layout optimization measures to obtain helicopter aerodynamic performance benefit data.

[0030] In summary, the method provided in this embodiment carries out a real helicopter test in a full-size wind tunnel, installs a real helicopter 6 in the full-size wind tunnel test section, and uses a balance mechanism 2 and a strain bridge to measure the aerodynamic performance of the helicopter; establishes a method for conducting aerodynamic performance assessment tests under rotor, tail rotor and full-machine working conditions, and realizes the ability to assess the aerodynamic performance of the helicopter and verify the aerodynamic performance benefits after the aerodynamic layout is optimized; on this basis, the aerodynamic layout of the whole aircraft is optimized to obtain the aerodynamic performance benefit data of the helicopter, solve the problem of comprehensive optimization design of the aerodynamic layout of the whole aircraft in the development of the helicopter, and avoid local distortion caused by model reduction, which will greatly improve the development process of my country's helicopters, reduce development risks, shorten the development cycle, and provide more powerful technical support for the development of helicopter models.

[0031] In a feasible implementation mode, the helicopter cockpit control system is modified and operated and controlled in a ground control room during the test.

[0032] A feasible implementation method is that in step S1, the helicopter real machine 6 is installed on the balance mechanism 2 using a three-point supported belly-supported mechanism 1, and the belly-supported mechanism 1 has stiffness and damping adjustment functions to avoid resonance on the ground or in the air.

[0033] Furthermore, the tail strut 4 of the belly-supported mechanism 1 has a vertical stroke to realize the change of the rotor main shaft inclination angle, thereby realizing the simulation of the aerodynamic characteristics of the real helicopter 6 under different rotor main shaft inclination angles; in order to ensure that the real helicopter 6 can realize the effective change of the rotor main shaft inclination angle, the support point of the belly-supported mechanism 1 can be connected to the fuselage reinforcement frame through a hinge; based on this, the belly-supported mechanism 1 with three-point support effectively realizes the stability of the support of the real helicopter 6, that is, there are two support points supporting the front of the real helicopter 6, and the other support point supporting the tail of the real helicopter 6.

[0034] In a feasible implementation manner, the balance mechanism 2 is mounted on a turntable 3, and the turntable 3 is mounted on a base 5 on the wind tunnel floor. The existence of the turntable 3 enables the change of the helicopter's sideslip angle, thereby achieving a simulation of the aerodynamic characteristics of the helicopter at different sideslip angles.

[0035] Example 2 like Figure 1-Figure 3As shown, a ground simulation device for aerodynamic characteristics test of a real helicopter includes a base 5 installed on the ground of a wind tunnel, a turntable 3 is installed on the base 5, a balance mechanism 2 is arranged on the turntable 3, a belly-supported mechanism 1 with three points of support is arranged on the balance mechanism 2, and a real helicopter 6 can be installed on the belly-supported mechanism 1; specifically, the turntable 3 rotates with the balance mechanism 2 and the belly-supported mechanism 1, thereby rotating the real helicopter 6, thereby realizing the change of the sideslip angle of the helicopter, thereby realizing the aerodynamic characteristics simulation of the helicopter at different sideslip angles; during the aerodynamic characteristics simulation process, the balance mechanism 2 bears the vertical force provided by the real helicopter 6, thereby realizing the acquisition of the vertical aerodynamic force of the helicopter through the balance mechanism 2; it also includes a strain bridge arranged on the main transmission shaft and the tail transmission shaft, the torque of the rotor is obtained through the strain bridge on the main transmission shaft, and the torque of the tail rotor is obtained through the strain bridge on the tail transmission shaft.

[0036] Furthermore, the device can use the ground simulation method for testing the aerodynamic characteristics of a real helicopter 6 as described in any one of the first embodiments.

[0037] A feasible implementation manner, the tail support rod 4 of the belly-supporting mechanism 1 is supported on the tail of the real helicopter 6, and the tail support rod 4 is a telescopic rod with a vertical stroke. The change in the height supported by the tail support rod 4 causes the height of the tail of the real helicopter 6 to change. In conjunction with the unchanged height of the front end of the real helicopter 6, the change in the inclination angle of the rotor main shaft of the real helicopter 6 can be achieved, thereby realizing the simulation of the aerodynamic characteristics of the real helicopter 6 under different inclination angles of the rotor main shaft; in order to ensure that the real helicopter 6 can achieve effective changes in the inclination angle of the rotor main shaft, the support point of the belly-supporting mechanism 1 can be connected to the fuselage reinforcement frame through a hinge; based on this, the belly-supporting mechanism 1 with three-point support effectively realizes the stability of the support of the real helicopter 6, that is, there are two support points supported on the front of the real helicopter 6, and the other support point supported on the tail of the real helicopter 6.

[0038] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A ground simulation method for a real helicopter aerodynamic characteristics test, characterized by: The following steps are involved: S1: In the full-scale wind tunnel test section, the real helicopter (6) is directly or indirectly mounted on the balance mechanism (2); S2: Install strain bridges on the main drive shaft and tail drive shaft of the entire helicopter; S3: Start the wind tunnel, carry out aerodynamic characteristics test of the real helicopter (6); specifically comprising steps S31- S34; S31: Remove the tail rotor blades and conduct rotor aerodynamic performance assessment tests; S32: Remove the rotor blades and conduct aerodynamic performance test of the tail rotor; S33: Conduct aerodynamic performance assessment tests of helicopters under full aircraft operating conditions; S34: Conduct aerodynamic performance benefit verification tests under full helicopter operating conditions.

2. The ground simulation method for aerodynamic characteristics test of a real helicopter according to claim 1, characterized in that: In step S31, the specific process of the rotor aerodynamic performance assessment test is as follows: The hover test is conducted at different total pitches at the rotor operating speed; the forward flight test is conducted at different incoming flow speeds by adjusting the rotor main shaft inclination angle so that the vertical force of the balance mechanism (2) reaches a given value and the horizontal force is zero, thereby obtaining the aerodynamic force and torque data of the rotor in different states. In this state, the tail rotor hub rotates at its operating speed.

3. The ground simulation method for aerodynamic characteristics test of a real helicopter according to claim 1, characterized in that: In step S32, the specific process of the tail rotor aerodynamic performance assessment test is as follows: Both the hover test and the forward flight test are carried out at different collective pitches at the tail rotor operating speed to obtain the aerodynamic force and torque data of the tail rotor at different incoming flow velocities. In this state, the rotor hub rotates at its operating speed.

4. The ground simulation method for aerodynamic characteristics test of a real helicopter according to claim 1, characterized in that: In step S33, the specific process of the aerodynamic performance assessment test under the full helicopter working condition is as follows: Under the working speed of the rotor and tail rotor, the real flight condition of the helicopter is simulated. Under different incoming flow speeds, the rotor and tail rotor are manipulated to make the vertical force of the balance reach a given value, and the horizontal force, lateral force, yaw moment, roll moment, and pitch moment tend to zero, so as to obtain the rotor and tail rotor torque data under different working conditions; Or / and In step S34, the specific process of the aerodynamic performance assessment test under the full helicopter working condition is as follows: By adding fuselage guide vanes and side strip layout optimization measures, step S33 is repeated to obtain helicopter aerodynamic performance benefit data.

5. The ground simulation method for aerodynamic characteristics test of a real helicopter according to claim 1, characterized in that: In step S1, a real helicopter (6) is installed on a balance mechanism (2) using a three-point supported belly-supported mechanism (1), wherein the belly-supported mechanism (1) has a stiffness and damping adjustment function.

6. The ground simulation method for aerodynamic characteristics test of a real helicopter according to claim 5, characterized in that: The tail support rod (4) of the belly-supporting mechanism (1) has a vertical stroke to achieve a change in the inclination angle of the rotor main shaft.

7. The ground simulation method for aerodynamic characteristics test of a real helicopter according to claim 5, characterized in that: The balance mechanism (2) is mounted on a turntable (3), and the turntable (3) is mounted on a base (5) on the floor of the wind tunnel.

8. The ground simulation method for aerodynamic characteristics test of a real helicopter according to claim 1, characterized in that: In step S3, the helicopter cockpit control system is modified and operated and controlled in the ground control room during the test.

9. A ground simulation device for testing the aerodynamic characteristics of a real helicopter, characterized by: The invention comprises a base (5) installed on the floor of a wind tunnel, a turntable (3) being installed on the base (5), a balance mechanism (2) being arranged on the turntable (3), a belly-supported mechanism (1) supported at three points being arranged on the balance mechanism (2), and a real helicopter (6) being able to be installed on the belly-supported mechanism (1); and also comprises a strain bridge arranged on the main transmission shaft and the tail transmission shaft.

10. The ground simulation device for aerodynamic characteristics test of a real helicopter according to claim 9, characterized in that: The tail support rod (4) of the belly-supporting mechanism (1) is supported on the tail of the helicopter body (6), and the tail support rod (4) is a telescopic rod having a vertical stroke.

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