Free flight test method for ultrahigh Reynolds number internal and external flow coupling appearance ballistic target

Abstract

The invention provides a free flight test method for an ultrahigh Reynolds number internal and external flow coupling appearance ballistic target, and the method comprises the steps: intercepting a typical internal and external flow coupling part of a target aircraft as a modeling object, and generating an internal and external flow coupling test model; adjusting test conditions of a ballistic target free flight test, so that the free flight test Reynolds number of the internal and external flow coupling test model can truly simulate an ultrahigh Reynolds number under a flight condition; carrying out free flight aerodynamic performance simulation, free flight trajectory simulation, inner trajectory simulation and dynamics simulation of the internal and external flow coupling test model; and carrying out an ultrahigh Reynolds number ballistic target free flight test, and verifying the correctness of the ultrahigh Reynolds number internal and external flow coupling shape simulation method according to aerodynamic data, aerodynamic heat data and flow field feature images obtained by the test. According to the method, the success rate of the ultrahigh Reynolds number internal and external flow coupling appearance trajectory free flight test can be improved, pneumatic data in the internal and external flow coupling appearance free flight process can be obtained, and the correctness of the ultrahigh Reynolds number numerical simulation method can be verified.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft and relates to a free flight test method for an ultra-high Reynolds number internal and external flow coupled shape ballistic target. Background Art

[0002] High dynamic pressure aircraft face harsh flight environments such as higher resistance, higher heat flux, and greater loads, and the aircraft design margin is smaller, so it is particularly important to accurately obtain aircraft aerodynamic / thermal data. The existing conventional high-speed wind tunnels, shock wind tunnels, arc wind tunnels and other test facilities in China cannot directly simulate ultra-high Reynolds number flight environments, cannot truly reflect the complex flow field characteristics of internal and external flow coupling under ultra-high Reynolds numbers, and it is difficult to accurately obtain aircraft aerodynamic / thermal test data.

[0003] The ballistic target free flight test has the ability to truly simulate ultra-high Reynolds number flight conditions, and its measurement methods are rich, which can realize the measurement of aerodynamic / thermal data of the test model under ultra-high Reynolds number conditions. However, due to the strict launch mass constraints and large launch overload of the ballistic target free flight test, the strength requirements of the test model are high. Therefore, the previous ballistic target tests were basically without internal flow shape. The internal and external flow coupling shape is more complex and heavier than the shape without internal flow channel. The ballistic target free flight launch overload is greater, and the complex flow of internal and external flows during free flight puts higher requirements on flight stability. Therefore. Based on the requirements for improving the flight stability of ballistic target tests with internal and external flows, it is very necessary to carry out research on free flight test methods of ballistic targets with ultra-high Reynolds number internal and external flow coupling shapes. Summary of the invention

[0004] The present invention aims to solve at least one of the problems existing in the prior art.

[0005] To this end, the present invention provides a free flight test method for a ballistic target with an ultra-high Reynolds number and an internal and external flow coupled shape. The method can comprehensively solve the technical problems in the ballistic target test design, such as the internal and external flow coupled test model design, the ultra-high Reynolds number real simulation, and the model launch overload optimization. It can improve the success rate of the ultra-high Reynolds number internal and external flow coupled shape ballistic free flight test, obtain the aerodynamic data in the free flight process of the internal and external flow coupled shape, and verify the correctness of the ultra-high Reynolds number numerical simulation method.

[0006] The technical solution of the present invention is:

[0007] A free-flight test method for an ultra-high Reynolds number internal and external flow coupled ballistic target with a contour, the specific steps are as follows:

[0008] The first step is to select the typical internal and external flow coupling parts of the target aircraft as the modeling object according to the shape of the target aircraft and under the constraints of the caliber, launch mass and model strength of the ballistic target launcher, and generate the internal and external flow coupling test model;

[0009] The second step is to adjust the test conditions of the free-flight test of the ballistic target according to the actual flight conditions of the target aircraft, so that the Reynolds number of the free-flight test of the internal and external flow coupling test model can truly simulate the ultra-high Reynolds number under flight conditions;

[0010] The third step is to carry out free flight aerodynamic performance simulation and free flight trajectory simulation of the internal and external flow coupling test model based on the internal and external flow coupling test model established in the first step and the test conditions established in the second step;

[0011] The fourth step is to carry out internal ballistic simulation and dynamic simulation of the internal and external flow coupling test model based on the internal and external flow coupling test model established in the first step and the test conditions established in the second step;

[0012] The fifth step is to carry out free flight tests on ultra-high Reynolds number ballistic targets, verify the correctness of the ultra-high Reynolds number internal and external flow coupled shape simulation method based on the aerodynamic data, aerodynamic thermal data and flow field characteristic images obtained from the test, and verify whether the complex internal and external flow caused by the complex shape design of the internal and external flow coupling of the target aircraft meets the aircraft's air intake requirements.

[0013] Furthermore, the internal and external flow coupling test model in the first step is a non-scaled internal and external flow coupling test model.

[0014] Furthermore, in the second step, the test conditions include the pressure and temperature in the target chamber and the type of the gas medium in the target chamber.

[0015] Furthermore, in the simulation process of the third step, aerodynamic data and flight trajectory data under the expected test state and the flight speed deviation state are obtained simultaneously.

[0016] Furthermore, according to the obtained expected test state and the aerodynamic data and flight trajectory data under the flight speed deviation state, it is judged whether the internal and external flow coupling test model is in a static stable state during free flight. If it is a static stable state, jump to the fourth step; if it is not a static stable state, the mass distribution of the internal and external flow coupling test model is adjusted by adopting a material with a higher density than the raw material in the front section of the internal and external flow coupling test model and hollowing out the back section of the internal and external flow coupling test model, so that the center of mass of the internal and external flow coupling test model is located before the pressure center.

[0017] Furthermore, in the fourth step, the overload curve of the internal and external flow coupling test model during the launch process is obtained through internal ballistic simulation, and the launch structure strength data of the internal and external flow coupling test model is obtained through dynamic simulation; the structural stress and strain data of the internal and external flow coupling test model are obtained according to the dynamic simulation, and it is judged whether the internal and external flow coupling test model produces deformation or even damage sufficient to affect the flight flow field structure during the launch process, and whether the internal and external flow coupling test model meets the strength requirements under the launch overload;

[0018] If the internal and external flow coupling test model does not produce deformation or even damage sufficient to affect the flight flow field structure, and the internal and external flow coupling test model meets the strength requirements, the internal and external flow coupling test model can be processed accordingly and the ballistic target free flight test can be carried out on the processed internal and external flow coupling test model;

[0019] If the internal and external flow coupling test model produces deformation or even damage that is sufficient to affect the flight flow field structure, and the internal and external flow coupling test model does not meet the strength requirements, the launch impact load can be reduced by optimizing the launch loading parameters and adjusting the test conditions of the target chamber while ensuring a true simulation of the Reynolds number, thereby reducing the strength requirements of the internal and external flow coupling test model, so that the internal and external flow coupling test model can meet the strength requirements.

[0020] Furthermore, in the fourth step, the method for optimizing the launch loading parameters is: by adjusting the launch charge, the light gas section inflation volume and the compression piston weight, the launch peak overload is reduced under the premise of unchanged total acceleration, thereby reducing the strength requirements during the launch of the internal and external flow coupling test model.

[0021] Furthermore, in the fourth step, the method of adjusting the test conditions of the target chamber is as follows: the temperature in the target chamber in the test conditions obtained in the second step is set to T, the pressure is set to P, the gas viscosity of the gas medium in the target chamber is set to μ, and the molar mass is set to M;

[0022] When adjusting the test conditions of the target chamber, keep the temperature T constant, reduce the pressure P of the target chamber, and select a gas medium with a gas viscosity equal to μ and a molar mass greater than M, thereby reducing the gas constant R of the gas medium;

[0023] Under the premise of ensuring that the Reynolds number Re and the dimensionless velocity a are equal to those in the second step, the requirement of reducing the launch speed v is achieved, thereby reducing the launch impact load.

[0024] Furthermore, in the fifth step, the data obtained from the experiment are: obtaining the posture data of the internal and external flow coupling test model during free flight through the binocular posture system; obtaining the aerodynamic data of the model through aerodynamic parameter identification; obtaining the aerodynamic thermal data of the internal and external flow coupling test model during free flight through long-wave infrared; and obtaining the complex flow field characteristics of the internal and external flow coupling through shadow imaging.

[0025] Furthermore, in the fifth step, if the simulation data of aerodynamic data, aerodynamic thermal data and flow field characteristics are consistent with the test results and meet the air intake requirements of the aircraft, the ultra-high Reynolds number numerical simulation method in the third and fourth steps is correct, and the test data of the internal and external flow coupling test model is saved. The test data can be used as a simulation database for subsequent simulation methods;

[0026] If the simulation data of aerodynamic data, aerodynamic thermal data and flow field characteristics do not match the test results, or do not meet the aircraft intake requirements, repeat the first to fifth steps until they are met.

[0027] By applying the above technical solution, the present invention has the following beneficial effects:

[0028] (1) The present invention proposes a free flight test method for an ultra-high Reynolds number internal and external flow coupled ballistic target with a shaped shape, and specifically proposes a free flight test method for an ultra-high Reynolds number internal and external flow coupled ballistic target with a shaped shape that comprehensively considers the complex flow of ultra-high Reynolds number internal and external flow coupled and the high mass and high launch overload. The ultra-high Reynolds number internal and external flow coupled ballistic target free flight test is designed by adopting a method that combines "multi-constraint design of complex model of internal and external flow coupling + comprehensive adjustment of target chamber test conditions + optimization of internal ballistic overload". The test method introduces the design ideas and test design requirements of the ballistic target free flight model, and has achieved the expected effect after effective verification by numerical calculation and ballistic target free flight test. It has the conditions for engineering application and can be used to guide the subsequent free flight test design of ultra-high Reynolds number internal and external flow coupled ballistic target with a shaped shape.

[0029] (2) The present invention meets the requirements of safe launch and flight attitude stability in ballistic target tests by designing an internal and external flow coupling test model with high strength, high stability and no scale constraints, and can ensure that the internal and external flow coupling test model can truly reflect the typical characteristics of the internal and external flow coupling of the target aircraft.

[0030] (3) The present invention can satisfy the true simulation or similar simulation of the Reynolds number and dimensionless velocity during the free flight of the model by comprehensively adjusting the test conditions in the target chamber, thereby ensuring that the free flight flow field of the model can truly reflect the characteristics of the coupled flow field of the internal and external flows when the target aircraft flies at an ultra-high Reynolds number.

[0031] (4) The present invention can reduce the launch peak overload through internal ballistic overload optimization, appropriately reduce the model strength design requirements, and improve launch reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The included drawings are used to provide a further understanding of the embodiments of the present invention, which constitute a part of the specification, are used to illustrate the embodiments of the present invention, and together with the text description, explain the principles of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 is a flow chart of the ballistic target free flight test method of the present invention;

[0034] Figure 2 It is the principle diagram of aerodynamic force identification of the present invention. DETAILED DESCRIPTION

[0035] It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0037] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0038] This embodiment provides a method for free flight test of an ultra-high Reynolds number internal and external flow coupled shape ballistic target. The method adopts a method combining "multi-constraint design of complex model of internal and external flow coupling + comprehensive adjustment of test conditions in target chamber + optimization of internal ballistic overload" to design an ultra-high Reynolds number internal and external flow coupled shape ballistic target free flight test. Figure 1 , the specific steps are as follows:

[0039] The first step is to intercept the typical internal and external flow coupling parts of the target aircraft as the modeling object according to the shape of the target aircraft, under the constraints of the caliber of the ballistic target launcher, the launch mass, and the model strength, generate an internal and external flow coupling test model, and modify the internal and external flow coupling test model. Since the model reduction ratio easily affects the real simulation of complex flow characteristics such as shock waves / boundary layer interference of the internal and external flow coupling shape, the internal and external flow coupling test model of this embodiment is a non-reduced internal and external flow coupling test model;

[0040] The second step is to set the test conditions of the ballistic target free flight test according to the actual flight conditions of the target aircraft, which include the pressure, temperature and type of gas medium in the target chamber; and by adjusting the pressure, temperature and type of gas medium in the target chamber, the free flight test Reynolds number of the internal and external flow coupling test model can truly simulate the ultra-high Reynolds number under flight conditions;

[0041] The third step is to carry out the free-flight aerodynamic performance simulation and free-flight trajectory simulation of the internal-external-flow coupling test model based on the internal-external-flow coupling test model established in the first step and the test conditions established in the second step. Since the flow of the internal-external-flow coupling shape is complex and the flight stability changes significantly, it is necessary to simultaneously obtain the aerodynamic data and flight trajectory data under the expected test state and the flight speed deviation state during the simulation process.

[0042] According to the obtained simulation data (i.e., aerodynamic data and flight trajectory data under the expected test state and the flight speed deviation state), combined with the measurement window position during the test, it is determined whether the internal and external flow coupling test model is in a static stable state during free flight and whether sufficient attitude data can be obtained (the static stable state and obtaining sufficient attitude data are causally related. If it is a static stable state, sufficient attitude data can be obtained. If it is not a static stable state, sufficient attitude data cannot be obtained). If it is a static stable state and sufficient attitude data can be obtained, jump to the fourth step;

[0043] If it is not in a static stable state and sufficient attitude data cannot be obtained, the mass distribution of the internal and external flow coupling test model is adjusted by using high-density materials in the front section of the internal and external flow coupling test model and hollowing out the back section of the internal and external flow coupling test model, so that the center of mass of the internal and external flow coupling test model is located before the pressure center, so as to enhance the flight stability of the internal and external flow coupling test model and ensure that the internal and external flow coupling test model can obtain sufficient measurement data during the free flight of the ballistic target in the expected test state and the flight speed deviation state;

[0044] The fourth step is to carry out internal ballistic simulation and dynamic simulation of the internal and external flow coupling test model based on the internal and external flow coupling test model established in the first step and the test conditions established in the second step; obtain the overload curve of the internal and external flow coupling test model during the launch process through internal ballistic simulation, and obtain the launch structure strength data of the internal and external flow coupling test model through dynamic simulation; obtain the structural stress and strain data of the internal and external flow coupling test model based on the dynamic simulation, judge whether the internal and external flow coupling test model produces large deformation or even damage that is sufficient to affect the flight flow field structure during the launch process, and determine whether the internal and external flow coupling test model meets the strength requirements under launch overload;

[0045] If the internal and external flow coupling test model does not produce a large deformation or even damage that is sufficient to affect the flight flow field structure, and the internal and external flow coupling test model meets the strength requirements, the internal and external flow coupling test model can be processed accordingly and the ballistic target free flight test can be carried out on the processed internal and external flow coupling test model;

[0046] If the internal and external flow coupling test model produces a large deformation or even damage that is enough to affect the flight flow field structure, and the internal and external flow coupling test model does not meet the strength requirements, the launch impact load can be reduced by optimizing the launch loading parameters and adjusting the test conditions of the target chamber while ensuring the true simulation of the Reynolds number, thereby reducing the strength requirements of the internal and external flow coupling test model, so that the internal and external flow coupling test model can meet the strength requirements;

[0047] Among them, the method for optimizing the launch loading parameters is: by adjusting the launch charge, the light gas section filling volume and the compression piston weight, the launch peak overload can be reduced under the premise of unchanged total acceleration, thereby reducing the strength requirements during the launch of the internal and external flow coupling test model.

[0048] The method for adjusting the test conditions of the target chamber is as follows: the temperature in the target chamber is T, the pressure is P, the gas viscosity of the gas medium in the target chamber is μ, and the molar mass is M in the test conditions obtained in the second step;

[0049] When adjusting the test conditions of the target chamber, keep the temperature T constant, reduce the pressure P of the target chamber, and select a gas medium with a gas viscosity approximately equal to μ and a molar mass greater than M, thereby reducing the gas constant R of the gas medium, as shown in formula (1);

[0050] Under the premise of ensuring that the Reynolds number Re and the dimensionless velocity a are similar to those in the second step, the requirement of reducing the launch velocity v is achieved, as shown in formulas (2) and (3), thereby reducing the launch impact load:

[0051]

[0052] Among them, Rg is the ideal gas constant, R is the gas constant, M is the gas molar mass, v is the flight speed, g is the specific heat ratio, T is the temperature, P is the pressure, d is the characteristic length, and m is the viscosity coefficient.

[0053] The fifth step is to carry out the free flight test of the ultra-high Reynolds number ballistic target after the internal and external flow coupling test model meets the strength requirements. The binocular posture system is used to obtain sufficient posture data of the internal and external flow coupling test model during free flight, and the aerodynamic force data of the model is identified by aerodynamic parameters (such as Figure 2 As shown in the figure); obtain the aerodynamic thermal data of the internal and external flow coupling test model during free flight through long-wave infrared; obtain the complex flow field characteristics of the internal and external flow coupling through shadow imaging;

[0054] The correctness of the ultra-high Reynolds number internal and external flow coupling shape simulation method is verified based on the obtained aerodynamic data, aerodynamic thermal data and flow field characteristic images, and whether the complex internal and external flow caused by the complex external and internal flow coupling shape design of the target aircraft meets the aircraft intake requirements;

[0055] If the simulation data of aerodynamic data, aerodynamic thermal data and flow field characteristics are consistent with the test results (that is, the difference between the simulation data and the test results is less than 10%), and meet the aircraft intake requirements, then the ultra-high Reynolds number numerical simulation method in the third and fourth steps is correct, and the test data of the internal and external flow coupling test model is saved. The test data can be used as a simulation database for subsequent simulation methods, reducing the number of subsequent free flight tests using the internal and external flow coupling test model. Only through simulation can the verification results be obtained to verify whether the aerodynamic characteristics of the target aircraft and the complex internal and external flow caused by the complex shape design of the internal and external flow coupling meet the requirements of the aircraft design.

[0056] If the simulation data of aerodynamic data, aerodynamic thermal data and flow field characteristics do not match the test results (i.e. the difference between the simulation data and the test results is greater than or equal to 10%), or do not meet the aircraft intake requirements, repeat the first to fifth steps until they are met.

[0057] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0058] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0059] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A free flight test method for an ultra-high Reynolds number internal and external flow coupled shape ballistic target, characterized in that: The specific steps are as follows: The first step is to select the typical internal and external flow coupling parts of the target aircraft as the modeling object according to the shape of the target aircraft and under the constraints of the caliber, launch mass and model strength of the ballistic target launcher, and generate the internal and external flow coupling test model; The second step is to adjust the test conditions of the free-flight test of the ballistic target according to the actual flight conditions of the target aircraft, so that the Reynolds number of the free-flight test of the internal and external flow coupling test model can truly simulate the ultra-high Reynolds number under flight conditions; The third step is to carry out the free-flight aerodynamic performance simulation and free-flight trajectory simulation of the internal-external flow coupling test model based on the internal-external flow coupling test model established in the first step and the test conditions established in the second step. The fourth step is to carry out internal ballistic simulation and dynamic simulation of the internal and external flow coupling test model based on the internal and external flow coupling test model established in the first step and the test conditions established in the second step; The fifth step is to carry out free flight tests on ultra-high Reynolds number ballistic targets, verify the correctness of the ultra-high Reynolds number internal and external flow coupled shape simulation method based on the aerodynamic data, aerodynamic thermal data and flow field characteristic images obtained from the test, and verify whether the complex internal and external flow caused by the complex shape design of the internal and external flow coupling of the target aircraft meets the aircraft's air intake requirements.

2. The method for free flight test of ultra-high Reynolds number internal and external flow coupled shape ballistic target according to claim 1, characterized in that: The internal and external flow coupling test model in the first step is a non-scaled internal and external flow coupling test model.

3. The method for free flight test of ultra-high Reynolds number internal and external flow coupled shape ballistic target according to claim 1, characterized in that: In the second step, the test conditions include the pressure and temperature in the target chamber and the type of the gas medium in the target chamber.

4. The method for free flight test of ultra-high Reynolds number internal and external flow coupled shape ballistic target according to claim 1, characterized in that: During the simulation process of the third step, aerodynamic data and flight trajectory data are obtained simultaneously under the expected test state and the flight speed deviation state.

5. The method for free flight test of ultra-high Reynolds number internal and external flow coupled shape ballistic target according to claim 4, characterized in that: According to the expected test state and the aerodynamic data and flight trajectory data under the flight speed deviation state, determine whether the internal and external flow coupling test model is in a static stable state during the free flight process. If it is a static stable state, jump to the fourth step; If it is not a statically stable state, the mass distribution of the internal and external flow coupling test model is adjusted by using a material with a higher density than the raw material in the front section of the internal and external flow coupling test model and hollowing out the back section of the internal and external flow coupling test model so that the center of mass of the internal and external flow coupling test model is located in front of the pressure center.

6. The method for free flight test of ultra-high Reynolds number internal and external flow coupled shape ballistic target according to claim 1, characterized in that: In the fourth step, the overload curve of the internal and external flow coupling test model during the launch process is obtained through internal ballistic simulation, and the launch structure strength data of the internal and external flow coupling test model is obtained through dynamic simulation; According to the dynamic simulation, the structural stress and strain data of the internal and external flow coupling test model are obtained to determine whether the internal and external flow coupling test model produces deformation or even damage sufficient to affect the flight flow field structure during the launch process, and to determine whether the internal and external flow coupling test model meets the strength requirements under launch overload; If the internal and external flow coupling test model does not produce deformation or even damage sufficient to affect the flight flow field structure, and the internal and external flow coupling test model meets the strength requirements, the internal and external flow coupling test model can be processed accordingly and the ballistic target free flight test can be carried out on the processed internal and external flow coupling test model; If the internal and external flow coupling test model produces deformation or even damage that is sufficient to affect the flight flow field structure, and the internal and external flow coupling test model does not meet the strength requirements, the launch impact load can be reduced by optimizing the launch loading parameters and adjusting the test conditions of the target chamber while ensuring a true simulation of the Reynolds number, thereby reducing the strength requirements of the internal and external flow coupling test model, so that the internal and external flow coupling test model can meet the strength requirements.

7. A free-flight test method for ultra-high Reynolds number internal and external flow coupled shape ballistic target as claimed in claim 6, characterized in that: In the fourth step, the method for optimizing the launch loading parameters is: by adjusting the launch charge, the light gas section filling volume and the compression piston weight, the launch peak overload is reduced under the premise of unchanged total acceleration, thereby reducing the strength requirements during the launch process of the internal and external flow coupling test model.

8. The method for free flight test of ultra-high Reynolds number internal and external flow coupled shape ballistic target according to claim 6, characterized in that: In the fourth step, the method of adjusting the test conditions of the target chamber is as follows: the temperature in the target chamber is T, the pressure is P, the gas viscosity of the gas medium in the target chamber is μ, and the molar mass is M in the test conditions obtained in the second step; When adjusting the test conditions of the target chamber, keep the temperature T constant, reduce the pressure P of the target chamber, and select a gas medium with a gas viscosity equal to μ and a molar mass greater than M, thereby reducing the gas constant R of the gas medium; Under the premise of ensuring that the Reynolds number Re and the dimensionless velocity a are equal to those in the second step, the requirement of reducing the launch speed v is achieved, thereby reducing the launch impact load.

9. The method for free flight test of ultra-high Reynolds number internal and external flow coupled shape ballistic target according to claim 1, characterized in that: In the fifth step, the data obtained from the experiment are: obtaining the posture data of the internal and external flow coupling test model during free flight through the binocular posture system; obtaining the aerodynamic data of the model through aerodynamic parameter identification; obtaining the aerodynamic thermal data of the internal and external flow coupling test model during free flight through long-wave infrared; and obtaining the complex flow field characteristics of the internal and external flow coupling through shadow imaging.

10. The method for free flight test of ultra-high Reynolds number internal and external flow coupled shape ballistic target according to claim 1, characterized in that: In the fifth step, if the simulation data of aerodynamic data, aerodynamic thermal data and flow field characteristics are consistent with the test results and meet the aircraft intake requirements, the ultra-high Reynolds number numerical simulation method in the third and fourth steps is correct, and the test data of the internal and external flow coupling test model is saved. The test data can be used as a simulation database for subsequent simulation methods; If the simulation data of aerodynamic data, aerodynamic thermal data and flow field characteristics do not match the test results, or do not meet the aircraft intake requirements, repeat the first to fifth steps until they are met.

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