Hot deformation insulation force transmission device for high temperature wind tunnel and aerodynamic force measurement method

Abstract

This invention belongs to the field of high-temperature wind tunnel testing technology, and discloses a thermal deformation isolation force transmission device and an aerodynamic force measurement method for high-temperature wind tunnels. The thermal deformation isolation force transmission device includes a high-temperature end adapter plate and a low-temperature end adapter plate that are parallel to each other vertically. A force transmission unit is set between the high-temperature end adapter plate and the low-temperature end adapter plate. The end force transmission unit fixes several longitudinal force transmission plates located on the outer side and several transverse force transmission plates located on the inner side through an end force transmission base. The internal force transmission unit fixes several transverse force transmission plates symmetrically arranged front and rear through an internal force transmission base. The aerodynamic force measurement method includes designing the thermal deformation isolation force transmission device; establishing a six-component aerodynamic force measurement test system for high-temperature wind tunnels; and conducting a six-component aerodynamic force measurement test in a high-temperature wind tunnel. The thermal deformation isolation force transmission device and the aerodynamic force measurement method effectively suppress the interference of thermal deformation of the ramjet engine test model on the wind tunnel balance, improving the accuracy of aerodynamic force measurement.

Description

Technical Field

[0001] This invention belongs to the field of high-temperature wind tunnel testing technology, specifically relating to a thermal deformation isolation force transmission device and aerodynamic force measurement method for high-temperature wind tunnels. Background Technology

[0002] Conducting ramjet engine propulsion tests in high-temperature wind tunnels is a crucial method for verifying the design parameters of ramjet engines, among which thrust-drag performance is one of the key indicators. Ramjet engine propulsion tests require simulating incoming flow parameters such as Mach number, total enthalpy, and dynamic pressure. The total temperature of the incoming flow can reach over 2000K, causing a drastic temperature rise and a large temperature gradient on the ramjet engine test model, leading to overall thermal deformation. To better measure the drag and thrust generated by the ramjet engine test model, it is necessary to mount the model on a force measuring device for aerodynamic measurements. This force measuring device is typically a wind tunnel balance.

[0003] The wind tunnel balance consists of a fixed frame, a floating frame, and a force measuring element. The floating frame is connected to the model frame on the test model and transmits the aerodynamic force on the test model to the force measuring element. The force measuring element obtains an electrical signal through its measuring circuit and uses a pre-calibrated balance formula to calculate the aerodynamic force in reverse.

[0004] A wind tunnel balance installed close to the model frame or inside the model skin is called an internal balance. This improves the accuracy of the wind tunnel balance measurement and reduces interference from the model support. However, ramjet engine test models are prone to significant temperature gradients in the high-temperature airflow of a high-temperature wind tunnel, causing thermal deformation, mainly manifested as bending deformation along the length of the ramjet engine test model. This, in turn, causes strain in the floating frame and force-measuring elements of the wind tunnel balance, resulting in additional output from the wind tunnel balance's measurement circuit and interfering with the force measurement results.

[0005] Furthermore, the thermal deformation of the ramjet engine test model is affected by multiple factors such as aerodynamic shape, internal structural stiffness, and total incoming flow temperature, making it difficult to predict accurately and quantitatively assess the impact of the thermal deformation of the ramjet engine test model on the force measurement results.

[0006] Currently, there is an urgent need to develop a thermal deformation isolation force transmission device and aerodynamic force measurement method for high-temperature wind tunnels. Summary of the Invention

[0007] One technical problem to be solved by the present invention is to provide a thermal deformation isolation force transmission device for high-temperature wind tunnels. Another technical problem to be solved by the present invention is to provide an aerodynamic force measurement method for high-temperature wind tunnels, so as to overcome the influence of model deformation on the balance measurement results when measuring aerodynamic forces with an internal balance.

[0008] The thermal deformation isolation force transmission device for high-temperature wind tunnels of the present invention includes a high-temperature end adapter plate and a low-temperature end adapter plate that are parallel to each other vertically; a force transmission unit is arranged between the high-temperature end adapter plate and the low-temperature end adapter plate, wherein symmetrical end force transmission units are arranged at the front and rear ends, and an internal force transmission unit is arranged in the center; the end force transmission unit fixes several longitudinal force transmission plates located on the outer side and several transverse force transmission plates located on the inner side through an end force transmission base, and the longitudinal force transmission plates and the transverse force transmission plates are perpendicular to each other; the internal force transmission unit fixes several transverse force transmission plates that are symmetrically arranged horizontally through an internal force transmission base.

[0009] Furthermore, the longitudinal and transverse force transmission plates of the end force transmission unit and the transverse force transmission plate of the internal force transmission unit are integrally formed by wire cutting, electrical discharge machining or 3D printing.

[0010] Furthermore, the end force transmission unit consists of one set at the front and one set at the rear, and the internal force transmission unit consists of one set or two sets arranged in sequence.

[0011] Furthermore, the longitudinal force transmission plates consist of 4 to 8 pieces, and the transverse force transmission plates consist of 4 to 8 pieces.

[0012] The aerodynamic measurement method for high-temperature wind tunnels of the present invention includes the following steps: S10. Design a thermal deformation isolation force transmission device; In the high-temperature inflow of the high-temperature wind tunnel, the test model will generate a temperature gradient, causing the test model to bend and deform along its length. To prevent the test model from bending and deforming along its length, a model frame is installed inside the test model to increase its strength. In order to transfer the aerodynamic force of the test model to the wind tunnel balance, a thermal deformation isolation force transmission device is set between the test model and the wind tunnel balance. The thermal deformation isolation force transmission device connects the model frame and the wind tunnel balance through parallel high-temperature end transition plates and low-temperature end transition plates, respectively. The aerodynamic force is transferred by setting a force transmission unit between the high-temperature end transition plates and the low-temperature end transition plates. Relatively strong stiffness is set in the Fx, Fy, Fz, Mx, and My directions of the end force transmission unit, and relatively strong stiffness is set in the Fx, Fz, and My directions of the internal force transmission unit. The combination of the end force transmission unit and the internal force transmission unit ensures that the thermal deformation isolation force transmission device has sufficient stiffness in all six components of Fx, Fy, Fz, Mx, My, and Mz, thereby realizing the effective transmission of the six components of aerodynamic force and aerodynamic torque of the test model. At the same time, by taking advantage of the fact that the stiffness of the end force transmission unit in the Mz direction or the internal force transmission unit in the Fy direction is relatively weak compared with the other directions, the bending deformation of the test model in the length direction is effectively isolated, suppressing the interference of the bending deformation of the test model in the length direction on the force measurement results of the wind tunnel balance. S20. Establish a six-component aerodynamic measurement and testing system for a high-temperature wind tunnel; The low-temperature end adapter plate is fixed to the upper surface of the wind tunnel balance with bolts to ensure that the connection is tight and does not loosen or slip. Then, the wind tunnel balance with the low-temperature end adapter plate fixed is installed in the model bracket. The model bracket blocks the high-temperature flow from the high-temperature wind tunnel from acting directly on the wind tunnel balance. The model frame is fixed inside the test model cavity to obtain an integrated assembly. The high-temperature end adapter plate is fixed to the lower surface of the model frame with bolts to ensure that the connection is tight and does not loosen or slip. A high-temperature wind tunnel six-component aerodynamic measurement test system is obtained. S30. Conduct a six-component aerodynamic measurement test in a high-temperature wind tunnel; A six-component aerodynamic force measurement experiment was conducted in a high-temperature wind tunnel. The six-component aerodynamic force and aerodynamic torque experienced by the test model were transmitted to the wind tunnel balance through a thermal deformation isolation force transmission device. The wind tunnel balance measured the six-component aerodynamic force and aerodynamic torque.

[0013] Furthermore, by changing the thickness and number of the longitudinal and transverse force transmission plates, the stiffness of the force transmission unit in the Fx, Fy, Fz, Mx, My, and Mz directions is adjusted. By matching model frames of different weights, the natural frequency of the high-temperature wind tunnel six-component aerodynamic measurement test system is improved.

[0014] The thermal deformation isolation force transmission device for high-temperature wind tunnels of the present invention realizes the transmission of six-component aerodynamic forces and aerodynamic torques on the test model through the arrangement and combination of longitudinal and transverse force transmission plates between the high-temperature end adapter plate and the low-temperature end adapter plate, and effectively suppresses the transmission of thermal deformation of the ramjet engine test model to the wind tunnel balance, thereby reducing the interference of bending thermal deformation of the high-temperature wind tunnel aerodynamic test model on the force measurement results of the balance.

[0015] The aerodynamic measurement method for high-temperature wind tunnels of the present invention uses a six-component aerodynamic measurement test system for high-temperature wind tunnels. By placing a thermal deformation isolation force transmission device between the ramjet engine test model and the wind tunnel balance, the method effectively suppresses the interference of thermal deformation of the ramjet engine test model on the wind tunnel balance and improves the accuracy of aerodynamic measurement. Attached Figure Description

[0016] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0017] Figure 1 This is a front view of the thermal deformation isolation force transmission device for high-temperature wind tunnels according to the present invention; Figure 2 This is a partial enlarged view of section I of the thermal deformation isolation force transmission device for high-temperature wind tunnels of the present invention; Figure 3 This is a partial enlarged view of section II of the thermal deformation isolation force transmission device for high-temperature wind tunnels of the present invention; Figure 4 This is a cross-sectional view of the thermal deformation isolation force transmission device for high-temperature wind tunnels according to the present invention; Figure 5 This is an assembly diagram of the thermal deformation isolation force transmission device for high-temperature wind tunnels according to the present invention.

[0018] In the figure, 1. High-temperature end adapter plate; 2. Low-temperature end adapter plate; 3. End force transmission base; 4. Internal force transmission base; 5. Longitudinal force transmission plate; 6. Transverse force transmission plate; 7. End force transmission unit; 8. Internal force transmission unit; 9. Model frame; 10. Wind tunnel balance; 11. Test model; 12. Model support. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] Example: Figures 1-4 As shown, the thermal deformation isolation force transmission device for high-temperature wind tunnels in this embodiment includes a high-temperature end adapter plate 1 and a low-temperature end adapter plate 2 that are parallel to each other vertically. A force transmission unit is set between the high-temperature end adapter plate 1 and the low-temperature end adapter plate 2, wherein symmetrical end force transmission units 7 are set at the front and rear ends, and an internal force transmission unit 8 is set at the center. The end force transmission unit 7 fixes several longitudinal force transmission plates 5 located on the outer side and several transverse force transmission plates 6 located on the inner side through the end force transmission base 3. The longitudinal force transmission plates 5 and the transverse force transmission plates 6 are perpendicular to each other. The internal force transmission unit 8 fixes several transverse force transmission plates 6 that are symmetrically arranged horizontally through the internal force transmission base 4.

[0021] Furthermore, the longitudinal force transmission plate 5 and the transverse force transmission plate 6 of the end force transmission unit 7, and the transverse force transmission plate 6 of the internal force transmission unit 8 are integrally formed by wire cutting, electrical discharge machining or 3D printing.

[0022] Furthermore, the end force transmission unit 7 has one set at the front and one set at the back, and the internal force transmission unit 8 is one set or two sets arranged in sequence.

[0023] Furthermore, the longitudinal force transmission plate 5 consists of 4 to 8 pieces, and the transverse force transmission plate 6 consists of 4 to 8 pieces.

[0024] The aerodynamic measurement method for high-temperature wind tunnels in this embodiment includes the following steps: S10. Design a thermal deformation isolation force transmission device; In the high-temperature inflow of the high-temperature wind tunnel, the test model 11 will generate a temperature gradient, causing the test model 11 to bend and deform in the length direction; To prevent the test model 11 from bending and deforming in the length direction, a model frame 9 is set inside the test model 11 to increase the strength of the test model 11; In order to transfer the aerodynamic force of the test model 11 to the wind tunnel balance 10, a thermal deformation isolation force transmission device is set between the test model 11 and the wind tunnel balance 10. The thermal deformation isolation force transmission device is connected to the model frame 9 and the wind tunnel balance 10 through the high-temperature end adapter plate 1 and the low-temperature end adapter plate 2, which are parallel to each other. The aerodynamic force is transferred by setting a force transmission unit between the high-temperature end adapter plate 1 and the low-temperature end adapter plate 2. The end force transmission unit 7 is provided with relatively strong stiffness in the Fx, Fy, Fz, Mx, and My directions, and the internal force transmission unit 8 is provided with relatively strong stiffness in the Fx, Fz, and My directions. The combination of the end force transmission unit 7 and the internal force transmission unit 8 ensures that the thermal deformation isolation force transmission device has sufficient stiffness in all six components of Fx, Fy, Fz, Mx, My, and Mz, thereby realizing the effective transmission of the six components of aerodynamic force and aerodynamic torque of the test model 11. At the same time, by taking advantage of the fact that the stiffness of the end force transmission unit 7 in the Mz direction or the internal force transmission unit 8 in the Fy direction is relatively weak compared to the other directions, the bending deformation of the test model 11 in the length direction is effectively isolated, and the interference of the bending deformation of the test model 11 in the length direction on the force measurement results of the wind tunnel balance 10 is suppressed. S20. Establish a six-component aerodynamic measurement and testing system for a high-temperature wind tunnel; like Figure 5 As shown, the low-temperature end adapter plate 2 is fixed to the upper surface of the wind tunnel balance 10 with bolts to ensure that the connection is tight and does not loosen or slip. Then, the wind tunnel balance 10 with the low-temperature end adapter plate 2 fixed is installed in the model bracket 12. The model bracket 12 blocks the high-temperature flow of the high-temperature wind tunnel from acting directly on the wind tunnel balance 10. The model frame 9 is fixed inside the test model 11 to obtain an integrated assembly. The high-temperature end adapter plate 1 is fixed to the lower surface of the model frame 9 with bolts to ensure that the connection is tight and does not loosen or slip. A high-temperature wind tunnel six-component aerodynamic measurement test system is obtained. S30. Conduct a six-component aerodynamic measurement test in a high-temperature wind tunnel; A high-temperature wind tunnel six-component aerodynamic force measurement test was carried out. The six-component aerodynamic force and aerodynamic torque of the test model 11 were transmitted to the wind tunnel balance 10 through a thermal deformation isolation force transmission device. The wind tunnel balance 10 measured the six-component aerodynamic force and aerodynamic torque.

[0025] Furthermore, by changing the thickness and number of the longitudinal force transmission plate 5 and the transverse force transmission plate 6, the stiffness of the force transmission unit in the Fx, Fy, Fz, Mx, My, and Mz directions is adjusted, and by matching model frames 9 of different weights, the natural frequency of the high-temperature wind tunnel six-component aerodynamic measurement test system is improved.

[0026] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. For those skilled in the art, all features disclosed in the present invention, or all steps in all methods or processes disclosed, except for mutually exclusive features and / or steps, can be combined in any way without departing from the principles of the present invention. The present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A thermal deformation isolation force transmission device for high-temperature wind tunnels, characterized in that, The heat deformation isolation force transmission device includes a high-temperature end adapter plate (1) and a low-temperature end adapter plate (2) that are parallel to each other. A force transmission unit is set between the high-temperature end adapter plate (1) and the low-temperature end adapter plate (2), wherein symmetrical end force transmission units (7) are set at the front and rear ends, and an internal force transmission unit (8) is set at the center. The end force transmission unit (7) fixes several longitudinal force transmission plates (5) located on the outside and several transverse force transmission plates (6) located on the inside through the end force transmission base (3). The longitudinal force transmission plates (5) and the transverse force transmission plates (6) are perpendicular to each other. The internal force transmission unit (8) fixes several transverse force transmission plates (6) that are symmetrical on the left and right through the internal force transmission base (4).

2. The thermal deformation isolation force transmission device for high-temperature wind tunnels according to claim 1, characterized in that, The longitudinal force transmission plate (5) and transverse force transmission plate (6) of the end force transmission unit (7) and the transverse force transmission plate (6) of the internal force transmission unit (8) are integrally formed by wire cutting, electrical discharge machining or 3D printing.

3. The thermal deformation isolation force transmission device for high-temperature wind tunnels according to claim 1, characterized in that, The end force transmission unit (7) is one set at the front and one set at the back, and the internal force transmission unit (8) is one set or two sets arranged in sequence.

4. The thermal deformation isolation force transmission device for high-temperature wind tunnels according to claim 1, characterized in that, The longitudinal force transmission plates (5) consist of 4 to 8 pieces, and the transverse force transmission plates (6) consist of 4 to 8 pieces.

5. An aerodynamic measurement method for high-temperature wind tunnels, comprising the thermal deformation isolation force transmission device for high-temperature wind tunnels as described in any one of claims 1 to 4, characterized in that, Includes the following steps: S10. Design a thermal deformation isolation force transmission device; In the high-temperature inflow of the high-temperature wind tunnel, the test model (11) will generate a temperature gradient, causing the test model (11) to bend and deform in the length direction; In order to avoid bending deformation of the test model (11) in the length direction, a model frame (9) is set in the inner cavity of the test model (11) to increase the strength of the test model (11); In order to transfer the aerodynamic force of the test model (11) to the wind tunnel balance (10), a thermal deformation isolation force transmission device is set between the test model (11) and the wind tunnel balance (10); the thermal deformation isolation force transmission device is connected to the model frame (9) and the wind tunnel balance (10) respectively through the high temperature end adapter plate (1) and the low temperature end adapter plate (2) which are parallel to each other, and the aerodynamic force is transferred by setting a force transmission unit between the high temperature end adapter plate (1) and the low temperature end adapter plate (2); The end force transmission unit (7) is set with relatively strong stiffness in the Fx, Fy, Fz, Mx, and My directions, and the internal force transmission unit (8) is set with relatively strong stiffness in the Fx, Fz, and My directions. The combination of the end force transmission unit (7) and the internal force transmission unit (8) makes the thermal deformation isolation force transmission device have sufficient stiffness in the six components of Fx, Fy, Fz, Mx, My, and Mz, thereby realizing the effective transmission of the six components of aerodynamic force and aerodynamic torque of the test model (11). At the same time, taking advantage of the fact that the stiffness of the end force transmission unit (7) in the Mz direction or the internal force transmission unit (8) in the Fy direction is relatively weak compared with the other directions, the bending deformation of the test model (11) in the length direction is effectively isolated, and the interference of the bending deformation of the test model (11) in the length direction on the force measurement results of the wind tunnel balance (10) is suppressed. S20. Establish a six-component aerodynamic measurement and testing system for a high-temperature wind tunnel; The low-temperature end adapter plate (2) is fixed to the upper surface of the wind tunnel balance (10) with bolts to ensure that the connection is tight and does not loosen or slip. Then the wind tunnel balance (10) with the low-temperature end adapter plate (2) fixed is installed in the model bracket (12). The model bracket (12) blocks the high-temperature flow of the high-temperature wind tunnel from acting directly on the wind tunnel balance (10). The model frame (9) is fixed in the inner cavity of the test model (11) to obtain an integrated assembly. The high-temperature end adapter plate (1) is fixed to the lower surface of the model frame (9) by bolts to ensure that the connection is tight and does not loosen or slip. A high-temperature wind tunnel six-component aerodynamic measurement test system is obtained. S30. Conduct a six-component aerodynamic measurement test in a high-temperature wind tunnel; A six-component aerodynamic force measurement experiment was carried out in a high-temperature wind tunnel. The six-component aerodynamic force and aerodynamic torque of the test model (11) were transmitted to the wind tunnel balance (10) through a thermal deformation isolation force transmission device. The wind tunnel balance (10) measured the six-component aerodynamic force and aerodynamic torque.

6. The aerodynamic measurement method for high-temperature wind tunnels according to claim 5, characterized in that, The longitudinal force transmission plate (5) and the transverse force transmission plate (6) adjust the stiffness of the force transmission unit in the Fx, Fy, Fz, Mx, My, and Mz directions by changing the thickness and number. By matching model frames (9) of different weights, the natural frequency of the high-temperature wind tunnel six-component aerodynamic measurement test system is improved.

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