A dual-support ventilation force measurement test device for high-speed wind tunnels and its application method

Abstract

This invention discloses a dual-support ventilation force measurement test device and its application method for high-speed wind tunnels, relating to the field of wind tunnel testing technology. It includes: a tail base; two support rods on both sides of the tail base; and dummy support rods fixed to the tail base. The front end of the tail base, serving as the windward surface, adopts a streamlined shape, and the rear end of the tail base is designed with a 1:10 conical connecting section. The front end of the dummy support rods is provided with a bifurcated structure for mounting multiple pressure rakes. The bifurcated structure is designed with elongated adjustment holes for adjusting the axial position of the pressure rakes, and the gap generated after axial position adjustment is filled by compensation blocks of corresponding sizes. This invention connects and fixes the dual-support ventilation force measurement test device to the wings on both sides of the model (the connection point is located after the air inlet), aiming to simultaneously solve the two major problems of multi-faceted internal flow channel encroachment and external flow field interference, and is convenient to install and has strong load-bearing capacity.

Description

Technical Field

[0001] This invention relates to the field of wind tunnel testing technology. More specifically, this invention relates to a dual-support ventilation force measurement testing device and its application method for high-speed wind tunnels. Background Technology

[0002] In high-speed wind tunnel testing, ventilation force measurement is a crucial step in evaluating the performance of an aircraft's air intake and its impact on the overall aerodynamic characteristics. This test requires accurately subtracting internal flow resistance by measuring the model's outlet airflow parameters and simulating different flight conditions by adjusting throttling devices to obtain accurate intake effect corrections. Currently, ventilation force measurement generally employs tail strut support and blade support belly support. The biggest advantage of tail strut support is minimal support interference, resulting in more accurate aerodynamic test data compared to belly support. Its disadvantages are that the balance strut inevitably encroaches on the limited flow space inside the model, often leading to insufficient internal flow cross-sectional area and an inability to realistically simulate the aircraft's intake state; while blade support belly support introduces significant support interference and poses a risk of cross-contamination between the internal and external flow, severely affecting the accuracy and reliability of the test data.

[0003] Therefore, it is necessary to develop a ventilation force measurement test device for high-speed wind tunnels that can ensure the integrity of the pipes inside the model while minimizing interference with the sensitive flow field near the model's air inlet, and accurately measure the correction amount of the air intake effect under different flow rates, thereby supporting the precise correction of the aerodynamic characteristics of the entire machine. Summary of the Invention

[0004] One object of the present invention is to solve at least the above-mentioned problems and / or defects, and to provide at least the advantages described below.

[0005] To achieve these objectives and other advantages of the present invention, a dual-support ventilation force measurement test device for a high-speed wind tunnel is provided, comprising: The tail base that cooperates with the support structure in the middle of the wind tunnel; Two support rods are installed on both sides of the tail base; A dummy support rod is fixed to the tail base by a locating pin; The tail base, which serves as the front end of the windward surface, adopts a streamlined shape. The rear end of the tail base is designed with a 1:10 conical connecting section. The conical connecting section is connected to the wind tunnel support in the middle by a wedge-shaped block tensioning method. The front end of the dummy support rod is provided with a bifurcated structure for mounting multiple pressure measuring rakes. The bifurcated structure is designed with elongated adjustment holes for adjusting the axial position of the pressure measuring rakes, and the gap generated after the axial position is adjusted is filled by a compensation block of corresponding size.

[0006] Preferably, a pressure measuring pipeline is designed on the symmetrical central axis of the tail base, and the pressure measuring pipeline I is guided to the through hole I in the middle support of the wind tunnel.

[0007] Preferably, the tail base is also provided with a signal acquisition line I, and the signal acquisition line I is guided to the lead hole I in the support in the middle of the wind tunnel; Each balance support rod has a lead hole II on its front side for threading the signal acquisition line II; The signal acquisition line I includes signal acquisition line II.

[0008] Preferably, the rear end of the dummy support rod is an equivalent connecting section, and the rear end of the dummy support rod is directly mounted on the tail base by two pins.

[0009] Preferably, the dummy support rod has pressure measuring pipes II on both sides for arranging the pressure measuring pipes II and guiding the pressure measuring pipes II to the through holes II in the tail base.

[0010] An application method for a dual-support ventilation force measurement test device includes: S1. After assembling the double-support ventilation force measurement test device, install it on the support in the middle of the wind tunnel; S2. After establishing a stable flow field in the high-speed wind tunnel, conduct a high-speed ventilation force measurement test. S3. Based on the measurement results of S2, the Mach number at the outlet of each internal flow channel is calculated to obtain the model internal resistance. X in ; S4. Based on the model's internal resistance, calculate the external axial force of the ventilation model using the following formula. X t : In the above formula, and The axial force measured by the balance and the second balance respectively. X d The bottom resistance is generated in parts of the model other than the inner flow channel.

[0011] Preferably, in S1, the assembly process of the dual-support ventilation force measurement test device is as follows: S10. Insert the conical section of the tail base into the corresponding interface of the support in the middle of the wind tunnel, and use wedge blocks to firmly tighten the tail base. S11. Insert the interface ends of the two balance rods into the predetermined positions on both sides of the tail base, and lock them in place with high-strength tension screws. S12. Install the dummy support rod onto the base using the positioning pin, and then install the pressure measuring rake onto the front end of the dummy support rod. S13. Adjust the pressure measuring rake to the required axial measurement position through the elongated hole on the dummy support rod bifurcation structure and tighten it. S14. For the actual gap generated after the adjustment in S13, select a compensation block of matching size for installation to ensure that the pressure measuring rake has no room for movement. S15. Connect all pressure measuring pipelines and signal lines of each balance and angle of attack sensor to complete the preparation of the entire test system.

[0012] Preferably, in S2, the test results of the high-speed ventilation force measurement test include: the overall load of the model measured using various balances, and the total pressure at the outlet of the internal flow channel of the multi-ventilation model measured using a pressure rake. and the static pressure at the outlet of the internal flow channel p e .

[0013] Preferably, in S3, the model internal resistance is... X in The method of obtaining it is: S30, if 0.528 < If the value is less than 1, the flow at the outlet of the internal flow channel is subsonic; otherwise, it is supersonic. S31. If the flow at the outlet of the inner channel is subsonic, then the average Mach number at the outlet of each inner channel is... M ei Obtained through the following formula: In the above formula, This represents the average total pressure at the outlet of the i-th internal flow channel. p ei This represents the average static pressure at the outlet of the i-th internal flow channel; If the flow at the outlet of the inner channel is supersonic, then the average Mach number at each outlet of the inner channel is... M ei Obtained through the following formula: S32. Considering the ventilation and blockage conditions of each internal flow channel, calculate the overall internal resistance of the internal flow channel in the model using the following formula. X in : In the above formula, C i To define the internal resistance calculation coefficient for ventilated or blocked states, C is used when the internal flow channel is in a ventilated state. i The value is 1 when the inner flow channel is in a blocked cone state. i The value is 0. X ini The internal resistance of each ventilation channel, X bi Let be the internal resistance of the flow channel within each plug cone, and , , A ei This represents the outlet area of ​​each internal flow channel. M ∞ Indicates the incoming Mach number. p ∞ This indicates the incoming static pressure.

[0014] The present invention has at least the following beneficial effects: This invention connects and fixes the dual-support ventilation force measurement test device to the wings on both sides of the model (the connection point is located after the air inlet), aiming to solve the two major problems of multi-firing internal flow channel encroachment and external flow field interference at the same time. It is easy to install and has a strong load-bearing capacity. This invention facilitates research on interference from different combinations of states by distinguishing between the ventilated and blocked states of each internal flow channel, while also improving the accuracy of internal resistance calculation in the blocked state.

[0015] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the dual-support ventilation force measurement test device of the present invention; Figure 2 for Figure 1 An enlarged schematic diagram of the front end of the dummy support rod engaging with the pressure measuring rake; Figure 3 This is a cross-sectional view of the dual-support ventilation force measurement test device of the present invention; Figure 4 for Figure 2 A magnified diagram of the reverse side; Among them, the tail base-1, front end-10, rear end-11, through hole I-12, lead wire hole I-13, balance support rod-2, lead wire hole II-20, dummy support rod-3, through hole II-31, front end of dummy support rod-32, elongated adjustment hole-33, pressure measuring rake-4, and compensation block-5. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0018] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0019] It should be noted that in the description of this invention, the orientations or positional relationships indicated by terms are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this invention. In addition, the terms "I" and "II" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed", "equipped", "sleeved / connected", "connected", etc., should be interpreted broadly. For example, "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; it can be a connection within two components. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0021] Figures 1-3 A dual-support ventilation force measurement test device for high-speed wind tunnels is shown, which is suitable for conducting ventilation force measurement wind tunnel tests on the entire high-speed wind tunnel of multiple-layout configurations. It mainly includes: a tail base 1, two balance rods 2, a dummy rod 3, a pressure measuring rake 4, and a compensation block 5.

[0022] Among them, the tail base 1 is the main load-bearing component of the dual-support ventilation force measurement test device. The front end 10 of the tail base is designed with a streamlined shape to reduce interference with the aerodynamic characteristics of the aircraft. The rear end 11 of the tail base is designed as a 1:10 conical connecting section, which is rigidly connected to the middle support of the wind tunnel by a wedge block tensioning method. At the same time, a through hole I12 is designed on the symmetrical central axis of the tail base 1 to arrange the pressure measurement pipeline and guide it into the middle support of the wind tunnel. The lead wire holes I13 are opened from both ends of the tail base 1 perpendicular to the symmetrical plane to pass through the signal acquisition lines of the balance and angle of attack sensor and guide them into the middle support of the wind tunnel.

[0023] Two balance rods 2 are symmetrically mounted on the tail base 1. Taking one of the balance rods 2 as an example, it is installed on the tail base 1 through a cuboid notch fit and is fixed with a tension screw. The balance and the balance rod 2 are connected by a conventional conical surface fit, and an anti-rotation key is added to prevent relative rotation. A lead wire hole II20 is opened on the side of the front end of the rod to pass through the signal acquisition line of the angle of attack sensor.

[0024] The rear end 30 of the dummy support rod 3 is an equivalent connecting section, directly installed on the tail base 1, and precisely and quickly installed and positioned using two pins. The dummy support rod 3 has through holes II 31 on both sides for arranging pressure measuring pipelines and guiding them into the tail base 1. The front end 32 of the dummy support rod has a bifurcated structure for mounting multiple pressure measuring rakes 4. This bifurcated structure is designed with elongated adjustment holes 33, which, together with fastening screws, allow for fine-tuning of the axial position of the pressure measuring rakes 4. Furthermore, as... Figure 4 As shown, the system is also equipped with a series of compensation blocks 5 of different sizes, which are used to precisely fill the mechanical gaps generated after adjustment.

[0025] An application method for a dual-support ventilation force measurement test device includes: S1. After assembling the double-support ventilation force measurement test device, install it on the support in the middle of the wind tunnel; The installation and operation of the dual-support ventilation force measurement test device follow the following standardized procedures: S10. Fix the base. Accurately insert the conical section of the tail base into the corresponding interface of the support in the middle of the wind tunnel, and use wedge blocks to firmly tighten it.

[0026] S11. Install the support rods, insert the interface ends of the first flat support rod and the second flat support rod into the predetermined positions on both sides of the tail base, and lock them in place with high-strength tension screws.

[0027] S12. Configure the dummy support rod and accurately install it onto the base using the locating pin. Then, install the pressure rake at the designated position at the front end of the dummy support rod.

[0028] S13. Fine adjustment: Adjust the pressure measuring rake to the required axial measurement position through the elongated hole on the dummy support rod bifurcation structure and tighten it.

[0029] S14. Gap compensation: Based on the actual gap generated after adjustment in step 4, select a compensation block of matching size for installation to ensure that the system has no room for movement.

[0030] S15. System integration and debugging: Connect all pressure measurement pipelines and signal lines of the balance and angle of attack sensor to complete the preparation of the entire test system.

[0031] S2. Conduct a high-speed ventilation force measurement test. In this step, after establishing a stable flow field in the high-speed wind tunnel, use a balance to measure the overall load on the model and use a pressure gauge to measure the total pressure at the outlet of the internal flow channel of the multi-ventilation model. and the static pressure at the outlet of the internal flow channel p e .

[0032] S3. After calculating the Mach number at the outlet of each internal flow channel, calculate the internal resistance of the model; Mach number at each internal flow channel outlet Mei (The subscript i represents the i-th internal flow channel, i=1,2……N) This can be determined based on the total outlet pressure of each corresponding internal flow channel. and the static pressure at the outlet of the internal flow channel p ei The calculation yielded: When 0.528 < When the speed of flow is less than 1, the flow at the outlet of the inner channel is subsonic. Therefore, the Mach number at the outlet of each inner channel is... M ei Obtained through the following formula: when When the flow rate is ≤0.528, the flow at the outlet of the inner channel is supersonic. Therefore, the Mach number at the outlet of each inner channel is... M ei Obtained through the following formula: .

[0033] Considering the ventilation and blockage states of each internal flow channel, the internal resistance of the internal flow channel in each ventilation state is: The internal resistance of the flow channel in each blocked cone state is: Considering the ventilation and blockage states of each internal flow channel facilitates the analysis of interference effects from different state combinations, while also improving the accuracy of calculating the internal resistance of the internal flow channel under blockage conditions. The overall internal resistance of the internal flow channel in the model is: S4. Correct the external axial force of the calculation model. After correcting the internal resistance of the flow channel and the bottom resistance of the model, the model resistance is: .

[0034] in, X t The external axial force of the ventilation model. and The axial force measured on the first and second days respectively, X d This method generates bottom resistance in other parts of the model besides the internal flow channels. It employs a double-support approach to reduce support interference, making it particularly suitable for multi-internal flow channel models. It also facilitates the analysis of mutual interference between different combinations of multiple internal flow channels.

[0035] The above solution is merely an illustration of a preferred example and is not limited thereto. When implementing this invention, appropriate substitutions and / or modifications can be made according to the user's needs.

[0036] The number of devices and processing scale described herein are for the purpose of simplifying the description of the invention. Applications, modifications, and variations of the invention will be readily apparent to those skilled in the art.

[0037] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for the present invention. Other modifications can be readily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and examples shown and described herein.

Claims

1. A dual-support ventilation force measurement test device for high-speed wind tunnels, characterized in that, include: The tail base that cooperates with the support structure in the middle of the wind tunnel; Two support rods are installed on both sides of the tail base; A dummy support rod is fixed to the tail base by a locating pin; The tail base, which serves as the front end of the windward surface, adopts a streamlined shape. The rear end of the tail base is designed with a 1:10 conical connecting section. The conical connecting section is connected to the wind tunnel support in the middle by a wedge-shaped block tensioning method. The front end of the dummy support rod is provided with a bifurcated structure for mounting multiple pressure measuring rakes. The bifurcated structure is designed with elongated adjustment holes for adjusting the axial position of the pressure measuring rakes, and the gap generated after the axial position is adjusted is filled by a compensation block of corresponding size.

2. The dual-support ventilation force measurement test device for high-speed wind tunnels as described in claim 1, characterized in that, The tail base is designed with a pressure measuring pipeline on its symmetrical central axis, and the pressure measuring pipeline I is guided to the through hole I in the support in the middle of the wind tunnel.

3. The dual-support ventilation force measurement test device for high-speed wind tunnels as described in claim 1, characterized in that, The tail base is also equipped with a signal acquisition line I, and the signal acquisition line I is guided to the lead hole I in the support in the middle of the wind tunnel. Each balance support rod has a lead hole II on its front side for threading the signal acquisition line II; The signal acquisition line I includes signal acquisition line II.

4. The dual-support ventilation force measurement test device for high-speed wind tunnels as described in claim 1, characterized in that, The rear end of the dummy support rod is an equivalent connecting section, and the rear end of the dummy support rod is directly installed on the tail base by two pins.

5. The dual-support ventilation force measurement test device for high-speed wind tunnels as described in claim 1, characterized in that, The dummy support rod has pressure measuring pipes II on both sides for arranging and guiding the pressure measuring pipes II to the through holes II in the tail base.

6. A method for applying a dual-support ventilation force measurement test device, which employs the dual-support ventilation force measurement test device for high-speed wind tunnels as described in any one of claims 1-5, characterized in that, include: S1. After assembling the double-support ventilation force measurement test device, install it on the support in the middle of the wind tunnel; S2. After establishing a stable flow field in the high-speed wind tunnel, conduct a high-speed ventilation force measurement test. S3. Based on the measurement results of S2, the Mach number at the outlet of each internal flow channel is calculated to obtain the model internal resistance. X in ; S4. Based on the model's internal resistance, calculate the external axial force of the ventilation model using the following formula. X t : In the above formula, and The axial force measured by the balance and the second balance respectively. X d The bottom resistance is generated in parts of the model other than the inner flow channel.

7. The application method of the dual-support ventilation force measurement test device as described in claim 6, characterized in that, In S1, the assembly process of the dual-support ventilation force measurement test device is as follows: S10. Insert the conical section of the tail base into the corresponding interface of the support in the middle of the wind tunnel, and use wedge blocks to firmly tighten the tail base. S11. Insert the interface ends of the two balance rods into the predetermined positions on both sides of the tail base, and lock them in place with high-strength tension screws. S12. Install the dummy support rod onto the base using the positioning pin, and then install the pressure measuring rake onto the front end of the dummy support rod. S13. Adjust the pressure measuring rake to the required axial measurement position through the elongated hole on the dummy support rod bifurcation structure and tighten it. S14. For the actual gap generated after the adjustment in S13, select a compensation block of matching size for installation to ensure that the pressure measuring rake has no room for movement. S15. Connect all pressure measuring pipelines and signal lines of each balance and angle of attack sensor to complete the preparation of the entire test system.

8. The application method of the dual-support ventilation force measurement test device as described in claim 6, characterized in that, In S2, the test results of the high-speed ventilation force measurement test include: the overall load of the model measured by each balance, and the total pressure at the outlet of the internal flow channel of the multi-ventilation model measured by a pressure rake. and the static pressure at the outlet of the internal flow channel p e .

9. The application method of the dual-support ventilation force measurement test device as described in claim 6, characterized in that, In S3, the model's internal resistance X in The method of obtaining it is: S30, if 0.528 < If the value is less than 1, the flow at the outlet of the internal flow channel is subsonic; otherwise, it is supersonic. S31. If the flow at the outlet of the inner channel is subsonic, then the average Mach number at the outlet of each inner channel is... M ei Obtained through the following formula: In the above formula, This represents the average total pressure at the outlet of the i-th internal flow channel. p ei This represents the average static pressure at the outlet of the i-th internal flow channel; If the flow at the outlet of the inner channel is supersonic, then the average Mach number at each outlet of the inner channel is... M ei Obtained through the following formula: S32. Considering the ventilation and blockage conditions of each internal flow channel, calculate the overall internal resistance of the internal flow channel in the model using the following formula. X in : In the above formula, C i To define the internal resistance calculation coefficient for ventilated or blocked states, C is used when the internal flow channel is in a ventilated state. i The value is 1 when the inner flow channel is in a blocked cone state. i The value is 0. X ini The internal resistance of each ventilation channel, X bi Let be the internal resistance of the flow channel within each plug cone, and , , A ei This represents the outlet area of ​​each internal flow channel. M ∞ Indicates the incoming Mach number. p ∞ This indicates the incoming static pressure.

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