暂冲式高速风洞阶梯-连续变迎角组合试验方法

Abstract

This invention discloses a combined stepped-continuous variable angle of attack (CTO) test method for transient high-speed wind tunnels, relating to the field of aerospace wind tunnel testing. It includes conducting multiple stepped-continuous CTO tests within the same subsonic / transonic aerodynamic measurement test using a combination of stepped and continuous CTO tests. The continuous CTO test portion adjusts the wind tunnel's real-time Mach number parameters through a combination of total pressure control and static pressure control algorithms. The stepped CTO test method is divided into forward stepped and reverse stepped tests; the continuous CTO test method is divided into forward continuous and reverse continuous tests. This invention provides a test method for transient high-speed wind tunnel testing, under the premise of high-precision flow field control, ensuring that stepped and continuous CTO test data can be simultaneously acquired within the same test run through a combination of stepped and continuous CTO tests, thereby improving test efficiency and reducing energy consumption.

Description

Technical Field

[0001] This invention relates to the field of aerospace wind tunnel testing. More specifically, this invention relates to a step-continuous variable angle of attack combined test method for a transient high-speed wind tunnel. Background Technology

[0002] Temporary high-speed wind tunnel testing methods include stepped variable angle of attack (QA) testing and continuous variable angle of attack (CVA) testing. The stepped QA test involves establishing the wind tunnel flow field, then moving the model's angle of attack from the initial angle to the first angle in a given angle of attack sequence and maintaining this angle until the flow field meets requirements. Stepped test data is then collected, followed by moving to the next angle of attack. This process continues until the stepped test data for the last angle of attack in the sequence is collected, at which point the model's angle of attack returns to the initial angle of attack, and the test is terminated. The given angle of attack sequence typically includes more than three model angles of attack. The CVA test involves establishing the wind tunnel flow field, then moving the model's angle of attack from the initial angle to the first angle in a given angle of attack sequence. The model then moves at a given speed to the last angle of attack in the sequence, ensuring the flow field always meets requirements while continuously collecting test data. Finally, the model moves from the last angle of attack in the given angle of attack sequence back to the initial angle of attack, and the test is terminated. The given angle of attack sequence typically includes only two model angles of attack.

[0003] Traditional high-speed wind tunnel tests can only perform stepped angle-of-attack tests or continuous angle-of-attack tests on a single vehicle. In order to obtain stepped angle-of-attack test data and continuous angle-of-attack test data under the same test conditions, two tests are required, resulting in low test efficiency and high energy consumption. 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 step-continuous variable angle of attack combined test method for a transient high-speed wind tunnel is provided. In the same subsonic and transonic aerodynamic measurement test, multiple step-continuous variable angle of attack tests are completed by combining step-continuous variable angle of attack and continuous variable angle of attack tests. The continuous variable angle of attack test part adjusts the real-time Mach number parameters of the wind tunnel by combining the total pressure control algorithm and the static pressure control algorithm.

[0006] The test methods for the stepped variable angle of attack are divided into: forward stepped test and reverse stepped test;

[0007] The test methods for continuous angle of attack are divided into: forward continuous and reverse continuous.

[0008] Preferably, the test method for the positive step is as follows:

[0009] The model's angle of attack moves from the first angle of attack step to the last angle of attack according to a given angle of attack sequence;

[0010] The test method for the reverse ladder is as follows:

[0011] The model's angle of attack moves from the last angle of attack step to the first angle of attack according to a given angle of attack sequence.

[0012] Preferably, the forward continuous testing method is as follows:

[0013] The model's angle of attack runs continuously from the first angle of attack to the last angle of attack in a given angle of attack sequence;

[0014] The reverse continuous test method is as follows:

[0015] The model's angle of attack runs continuously from the last angle of attack in a given angle of attack sequence to the first angle of attack.

[0016] Preferably, the multiple stepped-continuous angle of attack tests include: forward stepped-reverse continuous, forward stepped-forward continuous, forward continuous-reverse stepped, forward continuous-forward stepped, forward continuous-forward stepped, and forward stepped-reverse continuous-forward continuous.

[0017] Preferably, the static pressure control algorithm in the continuous angle of attack test section obtains the grid finger output displacement value Sz using the following formula:

[0018] S = f ( α k )+ f ( S k ,Today k )

[0019] In the above formula, k This refers to the current moment in the control cycle. f ( α k )for k The grid finger displacement value output by the static pressure reference model at any given time. f ( S k ,Today k )for k Real-time data drives the grid finger correction displacement of the model output;

[0020] The grating finger control system adjusts the grating finger to Sz to achieve real-time control of the Mach number.

[0021] Preferably, the gate finger correction displacement is driven by real-time data in the model output. f ( Sk ,Today k It is characterized by the following formula:

[0022]

[0023] In the above formula, f ( S k ,Today k The shift is the gate finger correction displacement output by the real-time data-driven model. j For gate finger coefficients, T To control the cycle, f ( α k -V*T ) represents the grid finger displacement value output by the static pressure reference model for the previous control cycle. α k The actual model angle of attack for the current control cycle. Yes The model's angle of attack is the constant speed. S k This represents the actual displacement of the gate finger during the current control cycle. k pM and k iM The Mach number coefficients, Today k This represents the actual Mach number for the current control cycle. Today g Set a value for the Mach number. Today k-T This is the actual Mach number of the previous control cycle.

[0024] Preferably, the grid finger displacement value output by the hydrostatic reference model is... f ( α k It is characterized by the following formula:

[0025]

[0026] In the above formula, α For the model's angle of attack, a,b,c,d,e,g,h These are the coefficients of the static pressure reference model, which are obtained by polynomial regression processing based on historical test data of stepped variable angle of attack tests, using actual grid finger displacement and actual angle of attack.

[0027] The present invention has at least the following beneficial effects: For transient high-speed wind tunnel tests, under the premise of high-precision flow field control, a test method is provided to ensure that step-variable angle of attack test data and continuous variable angle of attack test data can be obtained simultaneously in the same test run by combining step-variable angle of attack and continuous variable angle of attack test methods, thereby improving test efficiency and reducing energy consumption.

[0028] 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

[0029] Figure 1 This is a schematic diagram of the forward step-reverse continuous test method in Embodiment 1 of the present invention;

[0030] Figure 2 This is a flowchart illustrating the positive step-positive continuous test method in Embodiment 2 of the present invention;

[0031] Figure 3 This is a flowchart illustrating the forward continuous-reverse stepped test method in Embodiment 3 of the present invention.

[0032] Figure 4 This is a flowchart illustrating the forward continuous-forward stepped test method in Embodiment 4 of the present invention;

[0033] Figure 5 This is an example diagram of the forward step-reverse continuous test method in Example 1;

[0034] Figure 6 This is a schematic diagram of the Mach number control method for the continuous variable angle of attack test section of the present invention.

[0035] Figure 7 This is a schematic diagram of the Mach number adjustment process in the continuous variable angle of attack test section of this invention. Detailed Implementation

[0036] 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.

[0037] The stepped angle-of-attack test is divided into forward stepped and reverse stepped test modes. In the forward stepped test mode, the model's angle of attack follows a given angle-of-attack sequence, progressing from the first angle of attack step to the last. In the reverse stepped test mode, the model's angle of attack follows a given angle-of-attack sequence, progressing from the last angle of attack step to the first. The continuous angle-of-attack test is divided into forward continuous and reverse continuous test modes. In the forward continuous test mode, the model's angle of attack continuously progresses from the first angle of attack in a given angle-of-attack sequence to the last angle of attack. In the reverse continuous test mode, the model's angle of attack continuously progresses from the last angle of attack in a given angle-of-attack sequence to the first angle of attack.

[0038] The step-continuous variable angle of attack combined test method for transient high-speed wind tunnels can flexibly realize various step-continuous variable angle of attack test modes by combining forward step, reverse step, forward continuous, and reverse continuous test modes. It mainly includes four test modes: forward step-reverse continuous, forward step-forward continuous, forward continuous-reverse step, and forward continuous-forward step test modes. Furthermore, it can be extended according to test requirements, such as the forward step-reverse continuous-forward continuous test mode.

[0039] Example 1

[0040] Forward step-reverse continuous test method, such as Figure 1 As shown, it includes the following steps:

[0041] Step 1: Given the angle of attack sequence [ α 1 , α 2 , ..., α n The model's angle of attack was adjusted to the initial angle of attack. α 0 Establish wind tunnel flow field;

[0042] Step 2, the model's angle of attack is determined by... α 0 by V 1 Speed ​​up α 1 ;

[0043] Step 3: After the flow field meets the requirements, collect data. α 1 Angle of attack step test data;

[0044] Step 4 α 1 After the angle-of-attack step test data acquisition was completed, the model's angle of attack changed from α 1 by V 1 Speed ​​up α 2 ;

[0045] Step 5: After the flow field meets the requirements, collect data. α 2 Angle of attack step test data. Repeat steps 4 and 5 until... α n The angle-of-attack step test data collection is complete.

[0046] Step 6, the model's angle of attack is determined by... α n by V 2Running at a constant speed until α 1 During this period, the flow field was ensured to meet the requirements at all times, and test data was continuously collected.

[0047] Step 7, the model's angle of attack is determined by... α 1 by V 3 Speed ​​up α 0 ;

[0048] Step 8: Turn off the engine and end the test.

[0049] like Figure 5 As shown, let the initial angle of attack be... α 0 Given a model angle of attack of 0°. α The sequence is [-8, -6, -4, -2.5, -1, 0, 1, 2, 4, 5, 6, 8, 10, 12, 14, 15.5, 17, 19, 21, 23], and the flow field requirement is Mach number control deviation. ΔMa Within ±0.002, V 1 It is 3° / s. V 2 =1° / s, V 3 The speed is 1° / s, and the Mach number is 0.85.

[0050] Forward stepped-reverse continuous test mode: The model's angle of attack is run to 0°, the wind tunnel is started to establish the flow field, and the Mach number is adjusted to 0.85; when ΔMa Within ±0.002, the model's angle of attack increased to -8° at a rate of 3° / s; then when ΔMa Within ±0.002, stepped test data were collected; after data collection, the model's angle of attack was reduced from -8° to -6° at a speed of 3° / s; then when ΔMa Within ±0.002, stepped test data were collected; then the model angle was moved to the next angle-of-attack sequence at a speed of 3° / s, and when... ΔMa Within ±0.002, stepped test data were collected until the data for the last model with an angle of attack of 23° was completed; then the model angle of attack was moved from 23° to -8° at a constant speed of 1° / s, ensuring during this period... ΔMa The test data was continuously collected within ±0.002. After the model's angle of attack reached -8°, it was run at a speed of 1° / s to 0°, and then the test was ended by shutting down the engine.

[0051] from Figure 5 It can be seen that during the experiment, in the stepped variable angle of attack section, when the step is stable, it can meet the requirements. ΔMaWithin ±0.002, stepped test data were acquired; in the continuous variable angle of attack section, during constant angle of attack operation, ΔMa The data remains within ±0.002, meeting the requirements for obtaining continuous variable angle of attack test data. This testing method allows for the simultaneous acquisition of stepped variable angle of attack test data and continuous variable angle of attack test data in a single test.

[0052] Example 2

[0053] Positive step-positive continuous test method, such as Figure 2 As shown, it includes the following steps:

[0054] Step 1: Given the angle of attack sequence [ α 1 , α 2 , ..., α n The model's angle of attack was adjusted to the initial angle of attack. α 0 Establish wind tunnel flow field;

[0055] Step 2, the model's angle of attack is determined by... α 0 by V 1 Speed ​​up α 1 ;

[0056] Step 3: After the flow field meets the requirements, collect data. α 1 Angle of attack step test data;

[0057] Step 4 α 1 After the angle-of-attack step test data acquisition was completed, the model's angle of attack changed from α 1 by V 1 Speed ​​up α 2 ;

[0058] Step 5: After the flow field meets the requirements, collect data. α 2 Angle of attack step test data. Repeat steps 4 and 5 until... α n The angle-of-attack step test data collection is complete.

[0059] Step 6, the model's angle of attack is determined by... α n by V 1 Running at a constant speed until α 1 ;

[0060] Step 7, the model's angle of attack is determined by... α 1 by V 2 Running at a constant speed until α n During this period, the flow field was ensured to meet the requirements at all times, and test data was continuously collected.

[0061] Step 8, the model's angle of attack is determined by... α n by V 3 Speed ​​up α 0 ;

[0062] Step 9: Turn off the engine and end the test.

[0063] Example 3

[0064] Forward continuous-reverse step test method, such as Figure 3 As shown, it includes the following steps:

[0065] Step 1: Given the angle of attack sequence [ α 1 , α 2 , ..., α n The model's angle of attack was adjusted to the initial angle of attack. α 0 Establish wind tunnel flow field;

[0066] Step 2, the model's angle of attack is determined by... α 0 by V 1 Speed ​​up α 1 ;

[0067] Step 3: After the flow field meets the requirements, the model's angle of attack is adjusted from... α 1 by V 2 Running at a constant speed until α n During this period, the flow field was ensured to meet the requirements at all times, and test data was continuously collected.

[0068] Step 4: Run the model to its angle of attack. α n Afterwards, collect α n Angle of attack step test data;

[0069] Step 5 α n After the angle-of-attack step test data collection was completed, the model's angle of attack changed from...α n by V 1 Running at a constant speed until α n-1 ;

[0070] Step 6: After the flow field meets the requirements, collect data. α n-1 Angle of attack step test data. Repeat steps 5 and 6 until... α 1 Data acquisition for the angle-of-attack step test has been completed;

[0071] Step 7, the model's angle of attack is determined by... α 1 by V 3 Speed ​​up α 0 ;

[0072] Step 8: Turn off the engine and end the test.

[0073] Example 4

[0074] Positive continuous-positive stepped test method, such as Figure 4 As shown, it includes the following steps:

[0075] Step 1: Given the angle of attack sequence [ α 1 , α 2 , ..., α n The model's angle of attack was adjusted to the initial angle of attack. α 0 Establish wind tunnel flow field;

[0076] Step 2, the model's angle of attack is determined by... α 0 by V 1 Speed ​​up α 1 ;

[0077] Step 3: After the flow field meets the requirements, the model's angle of attack is adjusted from... α 1 by V 2 Running at a constant speed until α n During this period, the flow field was ensured to meet the requirements at all times, and test data was continuously collected.

[0078] Step 4, the model's angle of attack is determined by... α n by V 1 Speed ​​upα 1 ;

[0079] Step 5: After the flow field meets the requirements, collect data. α 1 Angle of attack step test data;

[0080] Step 6 α 1 After the angle-of-attack step test data collection was completed, the model's angle of attack changed from... α 1 by V 1 Running at a constant speed until α 2 ;

[0081] Step 7: After the flow field meets the requirements, collect data. α 2 Angle of attack step test data. Repeat steps 6 and 7 until... α n Data acquisition for the angle-of-attack step test has been completed;

[0082] Step 8, the model's angle of attack is determined by... α n by V 3 Speed ​​up α 0 ;

[0083] Step 9: Turn off the engine and end the test.

[0084] It should be noted that all the above-mentioned step-continuous variable angle of attack combined test methods for transient high-speed wind tunnels are based on the premise of high-precision flow field control (that is, only under the premise of high-precision flow field control can multiple step-continuous variable angle of attack combined test methods be flexibly realized in a single wind tunnel test). Among them, in the wind tunnel test, the high-precision flow field control method for the step-variable angle of attack test part is implemented by the subsonic static pressure control method of the ejector semi-return transient wind tunnel with patent application number CN202411278284.0.

[0085] For the high-precision flow field control section of the continuous variable angle of attack test, the data-driven transient wind tunnel subsonic Mach number control method proposed in this invention is adopted. In this data-driven transient wind tunnel subsonic Mach number control method, the total pressure control section uses the PID control method, and the total pressure control accuracy can be maintained within 0.1% throughout the entire process. For the static pressure control section, based on the static pressure control benchmark model and the real-time data-driven model, an innovative static pressure control algorithm is established. Mach number control parameters are obtained through existing historical data from stepped step tests (it should be noted that stepped step tests are also called stepped variable angle of attack tests). The principle diagram of the Mach number control method is shown below. Figure 6 As shown, specifically, the total pressure control algorithm of the total pressure control section is based on the total pressure setpoint and the actual total pressure collected and fed back in real time. That is, the total pressure control is achieved through the PID control method of the following formula:

[0086]

[0087] In the above formula, △ P 0 ( k ) represents the difference between the actual total pressure and the set total pressure at the current moment, Δ P 0 ( k- 1) is the difference between the actual total pressure and the total pressure set value at the previous moment. k p0 and k i0 This is the total pressure deviation correction factor. f (△ P 0 ) represents the displacement output value of the pressure regulating valve.

[0088] The static pressure control algorithm in the static pressure control section consists of two parts: a static pressure reference model and a real-time data-driven model. The static pressure control algorithm is characterized by the following formula:

[0089] S = f ( α )+ f ( Wed, Today )

[0090] In the above formula, S The grid finger output displacement value calculated by the final static pressure control algorithm. f ( α () represents the grid finger reference displacement value output by the static pressure reference model. f ( Wed, Today The ) is the gate finger correction displacement value output by the real-time data-driven model, that is, the final gate finger output displacement value is obtained by adding the gate finger reference displacement value and the gate finger correction displacement value;

[0091] The static pressure reference model outputs the reference displacement of the grating finger at the current moment and the reference displacement of the grating finger at the previous moment based on the model angle of attack, as shown in the following formula:

[0092]

[0093] In the above formula, a,b,c,d,e,g,h These are the coefficients of the static pressure reference model. α For the model's angle of attack, f ( α) represents the grid finger displacement value output by the static pressure reference model. The coefficients of the static pressure reference model can be obtained through polynomial regression based on the correspondence between the actual grid finger displacement and the actual angle of attack in the stepped test data (and each regression is an iterative optimization of the static pressure reference model coefficients).

[0094] The real-time data-driven model outputs the corrected displacement of the grating finger at the current moment, based on the Mach number setpoint, the actual Mach number of the wind tunnel at the current moment, and the actual displacement of the grating finger. The real-time data-driven model is characterized by the following formula:

[0095]

[0096] In the above formula, j For gate finger coefficients, T To control the cycle, f ( α-Va*T ) represents the grid finger displacement value output by the static pressure reference model for the previous control cycle. α The actual model angle of attack for the current control cycle. Yes The model's angle of attack is the constant speed. S This represents the actual displacement of the gate finger during the current control cycle. k pM and k iM The Mach number coefficients, Today This represents the actual Mach number for the current control cycle. Today g Set a value for the Mach number. Today -T This is the actual Mach number of the previous control cycle.

[0097] Example 5

[0098] like Figure 7 As shown, the Mach number adjustment process in the continuous variable angle of attack test section includes the following steps:

[0099] Step 1: Record the current control cycle time as k Collect the actual angle of attack of the model during the current control cycle. α k Actual Mach number Today k Actual grid finger displacement S k .

[0100] Step 2: Calculate the grid finger displacement value from the hydrostatic reference model. f ( α k ):

[0101] The gate finger correction displacement is calculated by a model driven by real-time data.f ( S k ,Today k ):

[0102] Step 3: Calculate the output displacement value of the gate finger S:S = f ( α k )+ f ( S k ,Today k ).

[0103] Step 4: Adjust the grid fingers of the grid finger control system to... S Adjust the Mach number at that point.

[0104] Step 5: Determine whether to stop Mach number adjustment. If stopped, stop calculating the grid finger output displacement value and maintain the grid finger displacement at the current position; if not stopped, then... k Assigned value k+T Then proceed to the next control cycle and repeat steps 1 to 5.

[0105] 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.

[0106] 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 method for combined stepped-continuous variable angle of attack test in a transient high-speed wind tunnel, characterized in that, In the same subsonic and transonic aerodynamic measurement test, a variety of stepped-continuous angle-of-attack tests were completed by combining stepped and continuous angle-of-attack tests. In the continuous angle-of-attack test, the real-time Mach number parameters of the wind tunnel were adjusted by combining the total pressure control algorithm and the static pressure control algorithm. The test methods for the stepped variable angle of attack are divided into: forward stepped test and reverse stepped test; The test methods for continuous angle of attack are divided into: forward continuous and reverse continuous. The static pressure control algorithm for the continuous angle of attack test section obtains the grid finger output displacement value Sz using the following formula: Sz = f ( α k )+ f ( Sz k Ma k ) In the above formula, k This refers to the current moment in the control cycle. f ( α k )for k The grid finger displacement value output by the static pressure reference model at any given time. f ( Sz k Ma k )for k Real-time data drives the grid finger correction displacement of the model output; The gate finger control system adjusts the gate finger to Sz To achieve real-time control of Mach number; Grid finger displacement values ​​output by the static pressure reference model f ( α k It is characterized by the following formula: In the above formula, α For the model's angle of attack, a,b,c,d,e,g,h These are the coefficients of the static pressure reference model, which are obtained by polynomial regression processing based on historical test data of stepped variable angle of attack tests, using actual grid finger displacement and actual angle of attack.

2. The step-continuous variable angle of attack combined test method for transient high-speed wind tunnel as described in claim 1, characterized in that, The test method for the positive step is as follows: The model's angle of attack moves from the first angle of attack step to the last angle of attack according to a given angle of attack sequence; The test method for the reverse ladder is as follows: The model's angle of attack moves from the last angle of attack step to the first angle of attack according to a given angle of attack sequence.

3. The step-continuous variable angle of attack combined test method for transient high-speed wind tunnel as described in claim 1, characterized in that, The positive continuous test method is as follows: The model's angle of attack runs continuously from the first angle of attack to the last angle of attack in a given angle of attack sequence; The reverse continuous test method is as follows: The model's angle of attack runs continuously from the last angle of attack in a given angle of attack sequence to the first angle of attack.

4. The step-continuous variable angle of attack combined test method for transient high-speed wind tunnel as described in claim 1, characterized in that, Multiple stepped-continuous angle of attack tests include: forward stepped-reverse continuous, forward stepped-forward continuous, forward continuous-reverse stepped, forward continuous-forward stepped, forward continuous-forward stepped, and forward stepped-reverse continuous-forward continuous.

5. The step-continuous variable angle of attack combined test method for a transient high-speed wind tunnel as described in claim 1, characterized in that, Real-time data-driven model output gate finger correction displacement f ( Sz k Ma k It is characterized by the following formula: In the above formula, f ( Sz k Ma k The shift is the gate finger correction displacement output by the real-time data-driven model. j For gate finger coefficients, T To control the cycle, f ( α k -Va*T ) represents the grid finger displacement value output by the static pressure reference model for the previous control cycle. α k The actual model angle of attack for the current control cycle. Va The model's angle of attack is the constant speed. Sz k This represents the actual displacement of the gate finger during the current control cycle. k pM and k iM The Mach number coefficients, Ma k This represents the actual Mach number for the current control cycle. Ma g Set a value for the Mach number. Ma k-T This is the actual Mach number of the previous control cycle.

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