Aerodynamic characteristic testing device and aerodynamic characteristic compensation and correction method under water surface aircraft pool test environment

Abstract

The invention discloses an aerodynamic characteristic test device and an aerodynamic characteristic compensation correction method in a water surface aircraft pool test environment, during an aerodynamic characteristic test in the water surface aircraft pool test environment, a towing device drives a side bridge, a heave rod, a navigation rod and an attitude control rod to move at the same time, and under the traction of a navigation piece, the attitude control rod is driven to move at the same time; the water surface aircraft model, the six-component balance, the single-component balance and the angle sensor cooperatively move along the course, and the six-component balance, the angle sensor and the single-component balance respectively record the gravity center position, the aerodynamic lift Lmf, the resistance Dmf, the attitude angle theta of the water surface aircraft model in the pitching direction and the tail aerodynamic lift Lma of the water surface aircraft model in the movement process; and a comprehensive aerodynamic characteristic data graph under the physical pool environment is formed. The operation method provided by the invention is simple and effective, and can directly support all water surface aircrafts to carry out lift compensation analysis.

Description

Technical Field

[0001] The invention belongs to the technical field of surface aircraft design and test research, and in particular relates to an aerodynamic characteristic test device and an aerodynamic characteristic compensation correction method for a surface aircraft in a water tank test environment. Background Art

[0002] In the process of designing and finalizing the surface aircraft, hydrodynamic tests of full-scale models are usually used to verify and evaluate the gliding motion, stability, water load and splash characteristics of the surface aircraft. However, in the water pool environment, the similarity between the full-scale model and the actual aircraft appearance and performance parameters mainly relies on the Froude similarity criterion. The aerodynamic similarity between the real aircraft and the scaled model is mainly based on the Reynolds number similarity criterion. The existence of the two similarity criteria will inevitably lead to large differences in aerodynamic characteristic parameters, such as lift coefficient, drag coefficient, and moment coefficient. When the full-scale model test is carried out in a physical water pool environment using the aerodynamic characteristic parameters obtained based on the hydrodynamic test method, the corresponding model gliding motion posture, motion frequency and overload impact parameters are greatly different from those of the real surface aircraft, which directly affects the optimization and design finalization of the surface aircraft. Summary of the invention

[0003] Purpose of the Invention

[0004] In order to improve the simulation accuracy of aerodynamic and hydrodynamic characteristics during a hydrodynamic test of a surface aircraft, the present invention provides an aerodynamic characteristic testing device and an aerodynamic characteristic compensation and correction method in a water tank test environment for a surface aircraft.

[0005] Inventing technical solutions

[0006] A device for testing aerodynamic characteristics of a water surface aircraft in a water pool test environment comprises a water surface aircraft model, a side bridge, a heave rod, a navigation rod, an attitude control rod, a navigation plate, a six-component force balance, a two-degree-of-freedom device, an angle sensor, a single-component force balance, an attitude control assembly, and an articulated device; a center of gravity plate is horizontally arranged in the water surface aircraft model, both ends of the center of gravity plate are connected to a vertically arranged longitudinal bulkhead, the longitudinal bulkhead is connected to the water surface aircraft model, the six-component force balance is connected to the upper end surface of the center of gravity plate, the six-component force balance is connected to the angle sensor through the two-degree-of-freedom device, the angle sensor is connected to the vertically arranged heave rod, the tail of the water surface aircraft model is connected to the attitude control assembly, the upper part of the attitude control assembly is connected to the horizontal plate through the articulated device, the single-component force balance is fixed on the horizontal plate, the single-component force balance is connected to the vertically arranged attitude control rod, and is fixed to the attitude control assembly, the lower part of the navigation rod passes through a hole on the navigation plate, and the upper parts of the navigation rod, the attitude control rod, and the heave rod are all fixed to the side bridge;

[0007] During the aerodynamic characteristics test of the surface aircraft in the water tank test environment, the towing device drives the side bridge, heave rod, navigation rod, and attitude control rod to move simultaneously. Under the traction of the navigation plate, the surface aircraft model and the six-component force balance, single-component force balance, and angle sensor move in coordination along the heading. The six-component force balance, angle sensor, and single-component force balance respectively record the center of gravity position and aerodynamic lift L of the surface aircraft model during the movement. mf , resistance D mf , the pitch angle θ of the surface aircraft model, the tail aerodynamic lift L ma , forming a comprehensive aerodynamic characteristics data map in a physical water pool environment.

[0008] Preferably, before conducting an aerodynamic characteristics test in a water surface vehicle pool test environment, the longitudinal attitude of the water surface vehicle model is adjusted, and the angle sensor feeds back the current attitude parameter in real time. When the value is consistent with the target value, the attitude control component is locked. At this time, the attitude angle θ of the water surface vehicle model in the pitch direction is fixed; the relative position h of the side bridge and the water surface is adjusted. At this point, the installation of the water surface vehicle model and the preparation of the state before the test are completed.

[0009] Preferably, the vertical line of the center of gravity of the water surface aircraft model always passes through the center of the six-component force balance, the two-degree-of-freedom device and the angle sensor.

[0010] Preferably, the two-degree-of-freedom device consists of a mounting base, a transverse rotating shaft, a transverse rotating shaft sleeve, a vertical support rod and a horizontal top plate. The mounting base is connected to the top of the six-component force balance 9, and the two ends of the transverse rotating shaft are respectively rotatably set in the transverse rotating shaft sleeve. The transverse rotating shaft sleeve is fixed on the mounting base, one end of the vertical support rod is fixedly connected to the middle position of the transverse rotating shaft, and the other end is fixedly connected to the horizontal top plate. The angle sensor is connected to the horizontal top plate.

[0011] Preferably, the center of gravity plate is arranged at the center of gravity of the water surface aircraft model.

[0012] Preferably, the centerline of the navigation film passes through the symmetry plane of the surface aircraft model and is higher than the bow waterline position.

[0013] Preferably, the bottom end of the attitude control assembly is connected and fixed to a positioning piece reserved on the surface aircraft model via a screw rod, the upper part of the attitude control assembly is hinged to one end of the hinged device, and the other end of the hinged device is hinged to the bottom surface of the horizontal plate.

[0014] An aerodynamic characteristic compensation and correction method using an aerodynamic characteristic test device in a water surface aircraft pool test environment, the method comprising:

[0015] Step 1: Obtain the aerodynamic characteristics of the surface aircraft model 1 under a series of fixed elevator rudder deflections δ by wind tunnel test or aerodynamic characteristics numerical analysis method. aUnder the condition of the total lift coefficient C of the surface aircraft model 1 relative to the center of gravity L , drag coefficient C D and moment coefficient C M The curve spectrum with the change of posture θ;

[0016] Step 2: Conduct aerodynamic characteristics test in a physical water pool environment, by adjusting the horizontal towing speed v, the pitch attitude angle θ of the water surface aircraft model, and the elevator deflection angle δ apy , obtain the aerodynamic lift L of the center of gravity position under a series of corresponding states mf , resistance D mf And the tail aerodynamic lift L ma Test value;

[0017] The test values ​​are converted to the results of the relative center of gravity position. According to the relative position of the force and the flight principle, the conversion is performed using formulas (1) to (3):

[0018] Aerodynamic lift coefficient at the center of gravity in a pool environment:

[0019]

[0020] Aerodynamic drag coefficient at the center of gravity in a pool environment:

[0021]

[0022] Moment coefficient of relative center of gravity in pool environment:

[0023]

[0024] In the above formula, S is the wing area of ​​the scaled model; ρ is the air density; is the average aerodynamic chord length of the model wing; L mf and D mf are the aerodynamic lift and aerodynamic drag at the center of gravity measured by the six-component force balance (9); L ma is the tail aerodynamic lift measured by the single-component force balance (12); g is the gravitational acceleration; θ is the attitude angle of the model in the pitch direction; L c is the distance between the center of gravity and the measurement center of the single-component force balance (12), Wherein, △X is the longitudinal distance between the measurement center and the center of gravity of the single-component force balance (12), △Z f is the height difference between the measurement center and the center of gravity of the six-component balance (9), △Z a is the height difference between the measurement center of the single-component force balance (12) and the measurement center of the six-component force balance (9);

[0025] Step 3: Take the aerodynamic characteristic coefficients obtained in step 1 and step 2 as the ordinate, the attitude angle θ in the pitch direction of the surface aircraft model as the abscissa, and the elevator deflection angle δ as the horizontal coordinate. a and δ apy The lift coefficient and moment coefficient curves are plotted as the variation. The moment coefficient C of the surface aircraft in the wind tunnel and hydrodynamic test environment are compared. M、 C mhy The curve of the attitude angle θ in the pitch direction of the surface aircraft model is used to find the elevator rudder deflection δ corresponding to the two sets of curves when the moment coefficients coincide. a目标 , δ apy对标 , and the corresponding lift coefficient C for downward rudder deflection L目标 and C Lhy对标 The lift force △L at the center of gravity position that needs to be compensated at each speed point during the hydrodynamic test of the surface aircraft model is calculated using formula (4):

[0026]

[0027] Preferably, the calculated lift △L at the center of gravity position is actually the lift difference at the center of gravity position when the surface aircraft model and the actual aircraft respectively meet the Froude similarity and Reynolds number similarity conditions. After obtaining this value, it is necessary to perform additional lift compensation correction on the center of gravity position when conducting a hydrodynamic drag test in a water tank environment. At this time, the test results obtained can truly represent the gliding performance of the surface aircraft.

[0028] Preferably, when searching for the test state under which the moment coefficients coincide under two environments, the moment coefficient C corresponding to the wind tunnel data is used. M The attitude angle θ curve of the surface aircraft model in the pitch direction is taken as the reference value, and the moment coefficient C under the hydrodynamic test environment is mhy The attitude angle θ curve of the surface aircraft model in the pitch direction is used for parameter comparison with the benchmark value. At this time, there are two possible situations:

[0029] a) There is a curve where the benchmark value and the reference value match: record the corresponding elevator rudder deflection δ a目标 , δ apy对标 , and the corresponding lift coefficient C for the downward rudder L目标 and C Lhy对标 , calculate the lift compensation size at the center of gravity position according to formula (4);

[0030] b) There is no curve where the benchmark value matches the reference value: Since the elevator deflection has an angle interval within a certain range, there may be a benchmark value that is not completely consistent with the reference value. In this case, it is necessary to compare the different elevator deflection angles δ near the reference value. apy C mhy Interpolate the curve that changes with the attitude θ to determine the δ corresponding to the reference valueapy对标 Then, the same method is used to apy对标 Two nearby groups C Lhy By interpolating the changing curve of the attitude angle θ in the pitch direction of the surface aircraft model, we can obtain the apy对标 The corresponding C Lhy对标 At this time, the lift compensation size at the center of gravity position is calculated according to formula (4).

[0031] Advantages of the present invention:

[0032] 1. The operation method proposed by the present invention is simple and effective, and can directly support all surface aircraft to carry out lift compensation analysis. During operation, the aerodynamic lift coefficient and moment coefficient corresponding to the Reynolds number similarity and Froude similarity conditions can be obtained based on the wind tunnel test / aerodynamic characteristics numerical analysis method and the aerodynamic characteristics test under the water tank test environment.

[0033] 2. The present invention can provide relatively accurate aerodynamic lift compensation parameters for hydrodynamic tests of scaled models of surface aircraft. The hydrodynamic characteristic tests conducted on the basis of aerodynamic lift compensation correction can more accurately reflect the actual motion state of the surface aircraft.

[0034] 3. The present invention does not require any structural hardware changes and has strong feasibility. On the basis of not changing the commonly used hydrodynamic test equipment and test methods for surface aircraft, the lift compensation value of the center of gravity position obtained by the present invention is used as the input, and the unloading size of the hydrodynamic test constant force unloading device is adjusted to carry out the hydrodynamic characteristics test of the surface aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The present invention is a schematic structural diagram of an aerodynamic characteristic testing device for a water surface aircraft in a hydrodynamic test environment.

[0036] Figure 2 Schematic diagram of test parameters and relative positions of aerodynamic characteristics test in a physical water pool environment.

[0037] Figure 3 a) is the curve of aerodynamic lift coefficient at the center of gravity position changing with attitude in a physical water pool environment, b) is the curve of moment coefficient at the center of gravity position changing with attitude in a physical water pool environment.

[0038] Figure 4 a) is the curve of aerodynamic lift coefficient changing with attitude based on wind tunnel test / numerical evaluation results, b) is the curve of moment coefficient changing with attitude based on wind tunnel test / numerical evaluation results.

[0039] Figure 5 It is a schematic diagram of the structure of a two-degree-of-freedom device.

[0040] In the figure: 1 surface aircraft model, 2 side bridge, 3 lifting rod, 4 navigation rod, 5 attitude control rod, 6 navigation plate, 7 longitudinal bulkhead, 8 center of gravity plate, 9 six-component force balance, 10 two-degree-of-freedom device, 11 angle sensor, 12 single-component force balance, 13 attitude control assembly, 14 articulated device. DETAILED DESCRIPTION

[0041] The present invention is achieved through the following technical solutions.

[0042] like Figure 1 As shown, an aerodynamic characteristics test device for a water surface aircraft in a water pool test environment includes a water surface aircraft model 1, a side bridge 2, a heave rod 3, a navigation rod 4, an attitude control rod 5, a navigation plate 6, a longitudinal bulkhead 7, a center of gravity plate 8, a six-component force balance 9, a two-degree-of-freedom device 10, an angle sensor 11, a single-component force balance 12, an attitude control assembly 13, and an articulated device 14. Among them, the six-component force balance 9, the angle sensor 11, and the single-component force balance 12 are test sensor devices.

[0043] The navigation plate 6 is made of aluminum plate material, and its center line passes through the symmetry plane of the surface aircraft model 1 and is higher than the waterline position of the bow. After confirming the position, it is bonded to the bow of the surface aircraft model 1 with carbon fiber cloth; the two vertical longitudinal bulkheads 7 and the horizontally placed center of gravity plate 8 are the internal structure of the surface aircraft model 1. They are designed and assembled according to the structural design and the center of gravity distribution position during the model processing process, and the two are fixed through preset threaded holes; the six-component force balance 9 is installed and fixed on the upper end surface of the center of gravity plate 8, and the two-degree-of-freedom device 10 and the angle sensor 11 are installed above the six-component force balance 9 in sequence. Among them, the centers of the six-component force balance 9, the two-degree-of-freedom device 10 and the angle sensor 11 always pass through the vertical line of the center of gravity of the surface aircraft model 1; the attitude control component 13 is an aluminum part with a horizontal bottom, and its bottom end is connected and fixed to the positioning plate reserved on the surface aircraft model 1 through a screw, and the top end is a horizontal aluminum plate with a hinge device 14, which is used for the installation of the single-component force balance 12. At this point, the surface aircraft model 1, the test sensors, the model and the attitude adjustment device form a fixed whole.

[0044] The two-degree-of-freedom device 10 is composed of a mounting base 101, a transverse rotation axis 102, a transverse rotation axis sleeve 103, a vertical support rod 104 and a horizontal top plate 105. The mounting base is connected to the top of a six-component force balance (9). The two ends of the transverse rotation axis are respectively rotatably arranged in the transverse rotation axis sleeve. The transverse rotation axis sleeve is fixed on the mounting base. One end of the vertical support rod is fixedly connected to the middle position of the transverse rotation axis, and the other end is fixedly connected to the horizontal top plate. The angle sensor (11) is connected to the horizontal top plate.

[0045] The side bridge 2 is arranged below the towing device of the test water pool, and is used to connect the test device and provide horizontal movement power; the lifting rod 3 is vertically placed directly above the surface aircraft model 1, and its upper end is fixed to the side bridge 2 by a screw, and the lower end is fixed to the upper end face of the angle sensor 11; the navigation rod 4 is vertically placed at the head end of the surface aircraft model 1, and passes through the center point of the hole groove of the navigation plate 6; the attitude control rod 5 is vertically installed at the tail of the surface aircraft model 1, and its upper end is fixed to the side bridge 2 by a screw, and the lower end is fixed to the upper end face of the single-component force balance 12.

[0046] Before conducting the aerodynamic characteristics test in the water tank test environment of the surface aircraft, the longitudinal attitude of the surface aircraft model 1 is adjusted by the two-degree-of-freedom device 10 above the center of gravity and the hinge device 14 at the tail of the surface aircraft model 1. The angle sensor 11 feeds back the current attitude parameter in real time. When the value is consistent with the target value, the attitude control component 13 is locked (the attitude control component 13 can be locked by tightening the screw at the hinge point between the hinge device 14 and the attitude control component 13. Similarly, the screw at the hinge point between the hinge device 14 and the horizontal plate can also be tightened). At this time, the longitudinal attitude θ of the surface aircraft model 1 is fixed. Adjust the relative position h of the side bridge 2 and the water surface to achieve position control of the test height of the surface aircraft model 1. At this point, the installation of the surface aircraft model 1 and the pre-test state preparation work are completed.

[0047] During the aerodynamic characteristic test of the surface aircraft in the water tank test environment, the towing device drives the side bridge 2, the heave rod 3, the navigation rod 4, and the attitude control rod 5 to move simultaneously. Under the traction of the navigation plate 6, the surface aircraft model 1 and all the test sensors move in coordination along the heading. The six-component force balance 9, the angle sensor 11, and the single-component force balance 12 respectively record the center of gravity position, aerodynamic lift L of the model during the movement. mf , resistance D mf , model fixed attitude θ, tail aerodynamic lift L ma In order to form a comprehensive aerodynamic characteristics data map in a physical water tank environment, the horizontal towing speed v, attitude θ and elevator deflection angle δ during the test apy All are experimental variables.

[0048] A method for compensating and correcting aerodynamic characteristics of a water surface aircraft in a water pool test environment using the above-mentioned test device comprises the following steps:

[0049] Step 1: Obtain the aerodynamic characteristics of the surface aircraft under a series of fixed elevator deflection δ by wind tunnel test or aerodynamic characteristics numerical analysis method. a The total lift coefficient C of the aircraft relative to the center of gravity is L , drag coefficient C D and moment coefficient C M The curve spectrum with the change of posture θ;

[0050] Step 2: In a physical water tank environment, based on the test steps in claim 1, conduct an aerodynamic characteristic test test, by adjusting the horizontal drag speed v, attitude θ and elevator deflection angle δ apy , obtain the aerodynamic lift L of the center of gravity position under a series of corresponding states mf , resistance D mf And the tail aerodynamic lift L ma Test value.

[0051] The test values ​​are converted to the results of the relative center of gravity position. According to the relative position of the force and the flight principle, the conversion is performed using formulas (1) to (3):

[0052] Aerodynamic lift coefficient at the center of gravity in a pool environment:

[0053]

[0054] Aerodynamic drag coefficient at the center of gravity in a pool environment:

[0055]

[0056] Moment coefficient of relative center of gravity in pool environment:

[0057]

[0058] In the above formula, S is the wing area of ​​the scaled model; ρ is the air density; is the average aerodynamic chord length of the model wing; L mf and D mf are respectively the aerodynamic lift and aerodynamic drag at the center of gravity measured by the six-component force balance 9; L ma is the tail aerodynamic lift measured by the single-component force balance 12; g is the gravity acceleration; θ is the attitude angle of the model in the pitch direction; L c is the distance between the center of gravity and the measurement center of the single-component force balance 12, Among them, △X is the longitudinal distance between the measurement center and the center of gravity of the single-component force balance 12, △Z f is the height difference between the measurement center and the center of gravity of the six-component balance 9, △Z a It is the height difference between the measurement center of the single-component force balance 12 and the measurement center of the six-component force balance 9.

[0059] Step 3: Take the aerodynamic characteristic coefficients obtained in step 1 and step 2 as the ordinate, attitude θ as the abscissa, and elevator deflection angle δ as the horizontal coordinate. a and δ apy The lift coefficient and moment coefficient curves are plotted as the variation. The moment coefficient C of the surface aircraft in the wind tunnel and hydrodynamic test environment are compared. M、 C mhyThe curves that change with the attitude angle θ, find the elevator rudder deflection δ corresponding to the two sets of curves when the moment coefficients coincide a目标 , δ apy对标 , and the corresponding lift coefficient C for downward rudder deflection L目标 and C Lhy对标 At this time, there is a certain difference between the lift coefficient under wind tunnel conditions and water pool conditions. Based on the wind tunnel test / numerical calculation results, the lift △L at the center of gravity position that needs to be compensated for at each speed point during the hydrodynamic test of the scaled model of the surface aircraft is calculated using formula (4):

[0060]

[0061] Before conducting aerodynamic characteristic compensation and correction analysis, it is necessary to use the above-mentioned test device to test the aerodynamic characteristics of the water surface aircraft in the gliding state in the physical water pool environment, and use wind tunnel tests or aerodynamic characteristic numerical analysis methods to obtain the aerodynamic characteristic data results of the water surface aircraft that meet the Reynolds number similarity criterion. That is, step 1 and step 3.

[0062] The calculated lift △L at the center of gravity position is actually the lift difference at the center of gravity position when the surface aircraft model and the actual aircraft respectively meet the Froude similarity and Reynolds number similarity conditions. After obtaining this value, it is necessary to perform additional lift compensation correction on the center of gravity position when conducting hydrodynamic towing tests in a water pool environment (usually this can be achieved with the help of a dynamic constant force unloading device). At this time, the test results obtained can truly represent the gliding performance of the surface aircraft.

[0063] When looking for the test state under which the moment coefficients coincide under two environments, the moment coefficient C corresponding to the wind tunnel data is used. M The curve of the change with attitude θ is the reference value, and the moment coefficient C under the hydrodynamic test environment mhy The curve of attitude θ changes with the reference value for parameter comparison. At this time, there are two possible situations:

[0064] a) There is a curve where the benchmark value and the reference value match: record the corresponding elevator rudder deflection δ a目标 , δ apy对标 , and the corresponding lift coefficient C for the downward rudder L目标 and C Lhy对标 , calculate the lift compensation size at the center of gravity according to formula (4);

[0065] b) There is no curve where the benchmark value and the reference value match: Since the elevator deflection has an angle interval within a certain range, there may be a benchmark value that is not completely consistent with the reference value. In this case, it is necessary to compare the different elevator deflection angles δ near the reference value. apy C mhy Interpolate the curve that changes with the attitude θ to determine the δ corresponding to the reference value apy对标Then, the same method is used to apy对标 Two nearby groups C Lhy By interpolating the curve of the change of posture θ, we can get apy对标 The corresponding C Lhy对标 At this time, the lift compensation size at the center of gravity position is calculated according to formula (4).

[0066] In this embodiment, after the test device is installed, the longitudinal attitude θ of the water surface aircraft model 1 is adjusted according to the test state requirements, and the vertical distance between the lowest point of the water surface aircraft model 1 and the water surface is controlled to be 20 mm by adjusting the relative position of the side bridge 2 and the water surface. In this example, the longitudinal attitude angle θ of the water surface aircraft model 1 is taken as 0°, 2°, 4°, 6°, and 8° respectively. The elevator deflection angle is -8°, -4°, 0°, and 4°. The horizontal speed of the towing device is set to 7m / s.

[0067] Then, the aerodynamic characteristics test in the water tank test environment is carried out: the elevator bias is fixed at a certain angle according to the test state, and the longitudinal posture of the water surface aircraft model 1 is adjusted in sequence. The towing device always drives the water surface aircraft model (1) to move horizontally at a speed of 7m / s. The six-component force balance (9), the angle sensor 11, and the single-component force balance 12 respectively record the center of gravity position of the model during the movement and the aerodynamic lift L mf / Resistance D mf , model fixed attitude θ, tail aerodynamic lift L ma The aerodynamic characteristic parameters and relative positions are as follows: Figure 2 shown.

[0068] Then the aerodynamic characteristic parameters at the center of gravity are converted:

[0069] According to the relative position of the force and the flight principle, the test values ​​are converted to the relative center of gravity using formulas (1) to (3). The aerodynamic coefficient is used as the ordinate, the attitude angle θ is used as the abscissa, and the elevator deflection angle δ is used as the horizontal coordinate. apy As the variation, plot the lift coefficient C Lhy , torque coefficient C mhy curve. Figure 3 This is the aerodynamic characteristic curve spectrum under the hydrodynamic test environment corresponding to this example.

[0070] For this example, different elevator deflection angles δ apy The lift coefficient C Lhy , torque coefficient C mhy The curves of the change with the attitude angle θ are basically parallel, but the values ​​have certain differences.

[0071] Then the aerodynamic characteristics compensation analysis under the water tank test environment is carried out:

[0072] The moment coefficient C corresponding to the wind tunnel dataM The curve of the change with attitude θ is the reference value, and the moment coefficient C under the hydrodynamic test environment mhy The curve of the change of attitude angle θ is used to compare the parameters with the benchmark value, and find the test state under the coincidence of torque coefficients in the two environments (such as Figure 4 For this example, the elevator deflection angle δ in the wind tunnel data a目标 =-2°, and there is a corresponding set of lift coefficients C L目标 , torque coefficient C M目标 By comparison, the torque coefficient C M目标 Curve and δ in hydrodynamic test environment apy对标 = Moment coefficient C at -4° mhy对标 Basically coincident, therefore, the lift coefficient curve corresponding to the elevator deflection angle is C Lhy对标 Value. Then the lift coefficient of the target rudder downward, the lift coefficient of the reference rudder downward and the difference between the two are shown in Table 1. From the data in the table, it can be seen that the difference in lift coefficient at the center of gravity position under Froude similarity and Reynolds number similarity conditions is between 1.2 and 1.45, and the average value is 1.31 in this embodiment. According to formula (4), the lift compensation size at different speeds during the hydrodynamic drag test in the pool environment can be calculated. The specific values ​​are shown in Table 2.

[0073] Table 1 Summary of aerodynamic lift coefficients under wind tunnel and water tank test environments

[0074]

[0075]

[0076] Table 1 Aerodynamic lift compensation table under water tank test environment

[0077] Serial number v(m / s) △L(kg) 1 3 0.86 2 4 1.52 3 5 2.38 4 6 3.42 5 7 4.66

[0078] Hydrodynamic drag test considering aerodynamic lift compensation:

[0079] When conducting hydrodynamic dragging tests in a water tank environment (including but not limited to surface aircraft wave resistance tests and wave resistance tests), additional lift compensation is applied vertically upward to the center of gravity position (usually achieved with the help of a dynamic constant force unloading device). The test results obtained at this time can truly represent the gliding performance of the surface aircraft.

[0080] By using the test device and correction method of the present invention, the aerodynamic lift and moment parameters at the relative center of gravity position under the water tank test environment can be obtained. On this basis, a comparison of wind tunnel test / numerical evaluation results based on the aerodynamic characteristics of surface aircraft is carried out, and the aerodynamic lift compensation value set based on different horizontal speeds under the physical water tank test environment is mastered to complete the aerodynamic lift correction of the surface aircraft's wave resistance and wave resistance tests, and provide input for the hydrodynamic performance verification and evaluation of the surface aircraft.

[0081] The protection scope of the present invention is not limited to the above-mentioned embodiments. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the scope of the present invention. If these changes and modifications fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include these changes and modifications.

Claims

1. An aerodynamic characteristics test device for a water surface aircraft in a water pool test environment, characterized in that: The invention comprises a water surface aircraft model (1), a side bridge (2), a heave rod (3), a navigation rod (4), an attitude control rod (5), a navigation plate (6), a six-component force balance (9), a two-degree-of-freedom device (10), an angle sensor (11), a single-component force balance (12), an attitude control assembly (13), and an articulated device (14); a center of gravity plate (8) is horizontally arranged in the water surface aircraft model (1), two ends of the center of gravity plate (8) are connected to a vertically arranged longitudinal bulkhead (7), the longitudinal bulkhead (7) is connected to the water surface aircraft model (1), the six-component force balance (9) is connected to the upper end surface of the center of gravity plate (8), and the six-component force balance (9) is connected to the upper end surface of the center of gravity plate (8) through two The degree of freedom device (10) is connected to an angle sensor (11), which is connected to a vertically arranged heave rod (3). The tail of the surface aircraft model (1) is connected to an attitude control assembly (13), the upper part of the attitude control assembly (13) is connected to a horizontal plate through a hinge device (14), a single-component force balance (12) is fixed on the horizontal plate, the single-component force balance (12) is connected to a vertically arranged attitude control rod (5), and is fixed to the attitude control assembly (13), the lower part of the navigation rod (4) passes through a hole on the navigation plate (6), and the upper parts of the navigation rod (4), the attitude control rod (5), and the heave rod (3) are all fixed to the side bridge (2); During the aerodynamic characteristic test of a water surface aircraft in a water tank test environment, the towing device drives the side bridge (2), the heave rod (3), the navigation rod (4), and the attitude control rod (5) to move simultaneously. Under the traction of the navigation plate (6), the water surface aircraft model (1) and the six-component force balance (9), the single-component force balance (12), and the angle sensor (11) move in coordination along the heading. The six-component force balance (9), the angle sensor (11), and the single-component force balance (12) respectively record the center of gravity position, aerodynamic lift L of the water surface aircraft model (1) during the movement. mf , resistance D mf , the pitch angle θ of the surface aircraft model, the tail aerodynamic lift L ma , forming a comprehensive aerodynamic characteristics data map in a physical water pool environment.

2. The aerodynamic characteristics testing device for a water surface aircraft in a water tank test environment according to claim 1, characterized in that: Before conducting an aerodynamic characteristic test in a water tank test environment of a water vehicle, the longitudinal attitude of the water vehicle model (1) is adjusted, and the angle sensor (11) feeds back the current attitude parameter in real time. When the value is consistent with the target value, the attitude control component (13) is locked, and the attitude angle θ of the water vehicle model (1) in the pitch direction of the water vehicle model is fixed; the relative position h of the side bridge (2) and the water surface is adjusted. At this point, the installation of the water vehicle model (1) and the pre-test state preparation work are completed.

3. The aerodynamic characteristics testing device for a water surface aircraft in a water tank test environment as claimed in claim 1, characterized in that: The vertical line of the center of gravity of the water surface aircraft model (1) always passes through the center of the six-component force balance (9), the two-degree-of-freedom device (10) and the angle sensor (11).

4. The aerodynamic characteristics testing device for a water surface aircraft in a water tank test environment as claimed in claim 1, characterized in that: The two-degree-of-freedom device (10) is composed of a mounting base, a transverse rotating shaft, a transverse rotating shaft sleeve, a vertical support rod and a horizontal top plate. The mounting base is connected to the top of a six-component force balance (9). The two ends of the transverse rotating shaft are rotatably arranged in the transverse rotating shaft sleeve respectively. The transverse rotating shaft sleeve is fixed on the mounting base. One end of the vertical support rod is fixedly connected to the middle position of the transverse rotating shaft, and the other end is fixedly connected to the horizontal top plate. The angle sensor (11) is connected to the horizontal top plate.

5. The aerodynamic characteristics testing device for a water surface aircraft in a water tank test environment as claimed in claim 1, characterized in that: The center of gravity plate (8) is arranged at the center of gravity position of the water surface aircraft model (1).

6. The aerodynamic characteristics testing device for a water surface aircraft in a water tank test environment as claimed in claim 1, characterized in that: The center line of the navigation piece (6) passes through the symmetry plane of the surface aircraft model (1) and is higher than the bow waterline position.

7. The aerodynamic characteristics testing device for a water surface aircraft in a water tank test environment as claimed in claim 1, characterized in that: The bottom end of the attitude control component (13) is connected and fixed to a positioning piece reserved on the water surface aircraft model (1) through a screw rod, and the upper part of the attitude control component (13) is hinged to one end of the hinge device (14), and the other end of the hinge device (14) is hinged to the bottom surface of the horizontal plate.

8. The method for compensating and correcting aerodynamic characteristics using the aerodynamic characteristics test device in a water tank test environment for a water surface aircraft as claimed in any one of claims 1 to 7, characterized in that: The method comprises: Step 1: Through wind tunnel tests or numerical analysis of aerodynamic characteristics, obtain the surface aircraft model (1) under a series of fixed elevator deflection δ a The total lift coefficient C of the surface aircraft model (1) relative to the center of gravity is L , drag coefficient C D and moment coefficient C M The curve spectrum with the change of posture θ; Step 2: Conduct aerodynamic characteristics test in a physical water pool environment, by adjusting the horizontal towing speed v, the pitch attitude angle θ of the water surface aircraft model, and the elevator deflection angle δ apy , obtain the aerodynamic lift L of the center of gravity position under a series of corresponding states mf , resistance D mf And the tail aerodynamic lift L ma Test value; The test values ​​are converted to the results of the relative center of gravity position. According to the relative position of the force and the flight principle, the conversion is performed using formulas (1) to (3): Aerodynamic lift coefficient at the center of gravity in a pool environment: Aerodynamic drag coefficient at the center of gravity in a pool environment: Moment coefficient of relative center of gravity in pool environment: In the above formula, S is the wing area of ​​the scaled model; ρ is the air density; is the average aerodynamic chord length of the model wing; L mf and D mf are the aerodynamic lift and aerodynamic drag at the center of gravity measured by the six-component force balance (9); L ma is the tail aerodynamic lift measured by the single-component force balance (12); g is the gravitational acceleration; θ is the attitude angle of the model in the pitch direction; L c is the distance between the center of gravity and the measurement center of the single-component force balance (12), Wherein, △X is the longitudinal distance between the measurement center and the center of gravity of the single-component force balance (12), △Z f is the height difference between the measurement center and the center of gravity of the six-component balance (9), △Z a is the height difference between the measurement center of the single-component force balance (12) and the measurement center of the six-component force balance (9); Step 3: Take the aerodynamic characteristic coefficients obtained in step 1 and step 2 as the ordinate, the attitude angle θ in the pitch direction of the surface aircraft model as the abscissa, and the elevator deflection angle δ as the horizontal coordinate. a and δ apy As the variation, the lift coefficient and moment coefficient curves are drawn; the moment coefficient C of the surface aircraft in the wind tunnel and hydrodynamic test environment are compared. M、 C mhy The curve of the attitude angle θ in the pitch direction of the surface aircraft model is used to find the elevator rudder deflection δ corresponding to the two sets of curves when the moment coefficients coincide. a目标 , δ apy对标 , and the corresponding lift coefficient C for downward rudder deflection L目标 and C Lhy对标 The lift force △L at the center of gravity position that needs to be compensated at each speed point during the hydrodynamic test of the surface aircraft model is calculated using formula (4):

9. The method according to claim 8, characterized in that The calculated lift △L at the center of gravity position is actually the lift difference at the center of gravity position when the surface aircraft model and the actual aircraft meet the Froude similarity and Reynolds number similarity conditions respectively. After obtaining this value, it is necessary to perform additional lift compensation correction on the center of gravity position when conducting the hydrodynamic dragging test in the pool environment. At this time, the test results obtained can truly represent the gliding performance of the surface aircraft.

10. The method for compensating and correcting aerodynamic characteristics of a water surface aircraft in a water tank test environment according to claim 8, characterized in that: When looking for the test state under which the moment coefficients coincide under two environments, the moment coefficient C corresponding to the wind tunnel data is used. M The attitude angle θ curve of the surface aircraft model in the pitch direction is taken as the reference value, and the moment coefficient C under the hydrodynamic test environment is mhy The attitude angle θ curve of the surface aircraft model in the pitch direction is used for parameter comparison with the benchmark value. At this time, there are two possible situations: a) There is a curve where the benchmark value and the reference value match: record the corresponding elevator rudder deflection δ a目标 , δ apy对标 , and the corresponding lift coefficient C for the downward rudder L目标 and C Lhy对标 , calculate the lift compensation size at the center of gravity position according to formula (4); b) There is no curve where the benchmark value matches the reference value: Since the elevator deflection has an angle interval within a certain range, there may be a benchmark value that is not completely consistent with the reference value. In this case, it is necessary to compare the different elevator deflection angles δ near the reference value. apy C mhy Interpolate the curve that changes with the attitude θ to determine the δ corresponding to the reference value apy对标 Then, the same method is used to apy对标 Two nearby groups C Lhy By interpolating the changing curve of the attitude angle θ in the pitch direction of the surface aircraft model, we can obtain the apy对标 The corresponding C Lhy对标 At this time, the lift compensation size at the center of gravity position is calculated according to formula (4).

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