Aircraft wall stress tensor sampling method, device, equipment and storage medium

Abstract

The application relates to the field of aerodynamics, and discloses an aircraft wall surface stress tensor sampling method, device, equipment and storage medium, the method comprising the following steps: generating a calculation grid according to the flow condition of high-altitude rare gas where an aircraft is located; randomly distributing simulation molecules in the calculation grid; the simulation molecules are used for characterizing gas molecules; performing linear motion of the simulation molecules according to the speed and time step length information of the simulation molecules in each iteration time step; and sampling the aircraft wall surface stress tensor if the motion track of the simulation molecules hits the aircraft wall surface. In this way, after the stress tensor is obtained, decomposition of the force acting on the wall surface can be realized, the research on a slip boundary condition model is facilitated, and then the rapid prediction of the aerodynamic characteristics of the aircraft in a high-altitude rare environment is realized.

Description

Technical Field

[0001] The present invention relates to the field of aerodynamics, and in particular to a method, device, equipment and storage medium for sampling aircraft wall stress tensors. Background Art

[0002] At altitudes above 85 km, the air is extremely rarefied, and the continuum assumption no longer holds. The information required for hypersonic vehicle design, such as the flow field around the vehicle and the distribution of physical quantities at the walls, cannot be provided by conventional computational fluid dynamics (CFD) methods and can only be obtained using kinetic numerical methods. The Direct Simulation Monte Carlo (DSMC) method is the most widely used kinetic method. When the flow rarefaction is not high, the Navier-Stokes equations plus slip boundary conditions are often used to reduce computational costs. However, current slip models can only provide a limited improvement over no-slip results and still differ significantly from the results of kinetic methods. Further analysis shows that the pressure at the wall can be decomposed into a static pressure contribution and a viscous normal stress contribution, but current slip models insufficiently consider the viscous normal stress term.

[0003] Existing DSMC methods simulate physical flows based on probability statistics. Macroscopic physical information is obtained by sampling and analyzing microscopic simulated molecular information. In engineering, wall pressure is typically calculated as the flux of normal momentum of simulated molecules passing through a unit wall area per unit time. This pressure has a different physical meaning from the static pressure in the flow field and typically has a different value. This approach fails to distinguish between the static pressure contribution and the viscous normal stress contribution. Summary of the Invention

[0004] In view of this, the present invention aims to provide a method, apparatus, device, and storage medium for sampling aircraft wall stress tensors, which can decompose the forces acting on the wall and be used for studying slip boundary condition models. The specific scheme is as follows:

[0005] A method for sampling an aircraft wall stress tensor, comprising:

[0006] Generate a computational grid based on the flow of rarefied gas at high altitudes where the aircraft is located;

[0007] randomly distributing simulated molecules within the computational grid; the simulated molecules are used to represent gas molecules;

[0008] In each iterative time step, the linear motion of the simulated molecules is simulated according to the velocity and time step information of the simulated molecules;

[0009] If the trajectory of the simulated molecule hits the wall of the vehicle, the stress tensor of the vehicle wall is sampled.

[0010] Preferably, in the above-mentioned aircraft wall stress tensor sampling method provided in an embodiment of the present invention, the process of sampling the aircraft wall stress tensor includes:

[0011] Sampling the first-order and second-order terms of the simulated molecular velocity;

[0012] Calculate the statistical average of each second-order term of the simulated molecular velocity;

[0013] The stress tensor of the aircraft wall is determined based on the density at the aircraft wall, the first-order terms of the simulated molecular velocity, and the statistical average of the second-order terms.

[0014] Preferably, in the above-mentioned aircraft wall stress tensor sampling method provided by an embodiment of the present invention, the sampling of the first-order terms and the second-order terms of the velocity of the simulated molecules includes:

[0015] The absolute value of the normal velocity of the simulated molecules is used as the weight to sample the first-order term of the incident simulated molecular velocity, the first-order term of the reflected simulated molecular velocity, the second-order term of the incident simulated molecular velocity, and the second-order term of the reflected simulated molecular velocity.

[0016] Preferably, in the above-mentioned aircraft wall stress tensor sampling method provided by the embodiment of the present invention, the following expression is used to sample the first-order term of the incident simulated molecular velocity:

[0017]

[0018] The first-order term of the reflection-simulated molecular velocity is sampled using the following expression:

[0019]

[0020] The second-order terms of the incident simulated molecular velocity are sampled using the following expression:

[0021]

[0022] The second-order term of the reflection-simulated molecular velocity is sampled using the following expression:

[0023]

[0024] Among them, N i is the number of simulated molecules incident on the wall during the sampling period, N r is the number of simulated molecules reflected from the wall, W F is the simulated molecular weight factor, m is the simulated molecular mass, u i ,vi ,w i is the velocity of the incident simulated molecule, u r ,v r ,w r To simulate molecular velocities for reflection, represents the absolute value of the normal component of the incident velocity of the simulated molecule, Represents the absolute value of the normal component of the reflection velocity of the simulated molecules.

[0025] Preferably, in the above-mentioned aircraft wall stress tensor sampling method provided in the embodiment of the present invention, the statistical average value of each second-order term of the simulated molecular velocity is calculated using the following formula:

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032] Among them, u, v, and w are the simulated molecular velocities.

[0033] Preferably, in the above-mentioned aircraft wall stress tensor sampling method provided in an embodiment of the present invention, before determining the aircraft wall stress tensor, the method further includes:

[0034] The density at the vehicle wall is determined by the equality of the normal stress at the vehicle wall and the normal momentum flux at the wall.

[0035] Preferably, in the above-mentioned aircraft wall stress tensor sampling method provided in the embodiment of the present invention, the aircraft wall stress tensor is determined using the following formula:

[0036]

[0037] Among them, P is the stress tensor of the aircraft wall, ρ is the density, and u0, v0, and w0 are the macroscopic velocities.

[0038] An embodiment of the present invention further provides an aircraft wall stress tensor sampling device, comprising:

[0039] The grid generation module is used to generate a computational grid based on the flow conditions of the rarefied gas at high altitudes where the aircraft is located;

[0040] a molecule arrangement module, configured to randomly distribute simulated molecules within the computational grid; the simulated molecules being used to represent gas molecules;

[0041] A molecular control module is used to simulate the linear motion of the molecules according to the velocity and time step information of the simulated molecules in each iterative time step;

[0042] The tensor sampling module is used to sample the stress tensor of the aircraft wall if the motion trajectory of the simulated molecule hits the aircraft wall.

[0043] An embodiment of the present invention further provides an aircraft wall stress tensor sampling device, comprising a processor and a memory, wherein when the processor executes a computer program stored in the memory, the aircraft wall stress tensor sampling method as provided in the embodiment of the present invention is implemented.

[0044] An embodiment of the present invention further provides a computer-readable storage medium for storing a computer program, wherein when the computer program is executed by a processor, the above-mentioned aircraft wall stress tensor sampling method provided in the embodiment of the present invention is implemented.

[0045] As can be seen from the above technical solution, the present invention provides a method for sampling the aircraft wall stress tensor, including: generating a computational grid based on the flow conditions of the rarefied gas at high altitude where the aircraft is located; randomly distributing simulated molecules within the computational grid; the simulated molecules are used to characterize the gas molecules; within each iterative time step, the linear motion of the simulated molecules is performed based on the velocity and time step information of the simulated molecules; and if the motion trajectory of the simulated molecules hits the aircraft wall, sampling the aircraft wall stress tensor.

[0046] In the above-mentioned aircraft wall stress tensor sampling method provided by the present invention, after generating a computational grid and randomly distributing simulated molecules, only the simulated molecules that collide with the aircraft wall are considered, rather than all the simulated molecules in the units adjacent to the wall. The aircraft wall stress tensor is sampled based on the simulated molecules that collide with the wall. After obtaining the stress tensor, the force acting on the wall can be decomposed, which can be used for the study of the slip boundary condition model, thereby realizing the rapid prediction of the aerodynamic characteristics of the aircraft in a high-altitude and rarefied environment.

[0047] In addition, the present invention also provides corresponding devices, equipment and computer-readable storage media for the aircraft wall stress tensor sampling method, further making the above method more practical, and the devices, equipment and computer-readable storage media have corresponding advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0049] Figure 1 A flow chart of a method for sampling an aircraft wall stress tensor provided in an embodiment of the present invention;

[0050] Figure 2 A schematic diagram of flow around a cylinder provided in an embodiment of the present invention;

[0051] Figure 3 A flow field pressure distribution diagram provided by an embodiment of the present invention;

[0052] Figure 4 A wall pressure distribution diagram provided by an embodiment of the present invention;

[0053] Figure 5 A distribution diagram of the normal components of the static pressure and viscous stress in the wall pressure components provided by an embodiment of the present invention;

[0054] Figure 6 A schematic structural diagram of an aircraft wall stress tensor sampling device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0056] The present invention provides a method for sampling the stress tensor of an aircraft wall, such as Figure 1 As shown, the following steps are included:

[0057] S101, generating a computational grid based on the flow of rarefied gas at a high altitude where the aircraft is located;

[0058] It should be noted that the primary application scenario of the aircraft wall stress tensor sampling method of the present invention is aircraft in a rarefied environment at high altitude. After executing step S101 to generate the computational grid, the DSMC calculation can begin. The DSMC calculation process includes flow field initialization, simulation of molecular motion, simulation of molecular collisions, simulation of molecular ordering, and simulation of molecular sampling.

[0059] S102, randomly distributing simulated molecules in the computational grid; the simulated molecules are used to represent gas molecules;

[0060] In practical applications, the number of simulated molecules per grid can be set to 10 to 20, and the speed can be specified based on the Maxwell equilibrium distribution.

[0061] S103, performing linear motion of the simulated molecule according to the velocity and time step information of the simulated molecule in each iterative time step;

[0062] S104. If the motion trajectory of the simulated molecule hits the wall of the aircraft, the stress tensor of the aircraft wall is sampled.

[0063] After executing step S104 , the processes of simulating molecular collision calculation, unit sampling, etc. may continue until the calculation is completed.

[0064] In the above-mentioned aircraft wall stress tensor sampling method provided in an embodiment of the present invention, after generating a computational grid and randomly distributing simulated molecules, only simulated molecules that collide with the aircraft wall are considered, rather than all simulated molecules in units adjacent to the wall. The aircraft wall stress tensor is sampled based on the simulated molecules that collide with the wall. After obtaining the stress tensor, the force acting on the wall can be decomposed, which can be used for the study of slip boundary condition models and the rapid prediction of the aerodynamic characteristics of the aircraft in a high-altitude and sparse environment.

[0065] Furthermore, in a specific implementation, in the above-mentioned aircraft wall stress tensor sampling method provided in an embodiment of the present invention, in the process of executing step S104 to sample the aircraft wall stress tensor, it can specifically include: first, sampling each first-order term and each second-order term of the simulated molecular velocity; then, calculating the statistical average of each second-order term of the simulated molecular velocity; finally, determining the aircraft wall stress tensor based on the density at the aircraft wall, the statistical average of each first-order term of the simulated molecular velocity, and each second-order term.

[0066] In the embodiment of the present invention, the stress tensor P is a second-order symmetric tensor and can be written as follows:

[0067]

[0068] Where ρ is the density at the wall, u′, v′, and w′ are the simulated molecular random thermal velocities in the (x, y, and z) coordinate directions. Accordingly, u, v, and w are the simulated molecular velocities, and u0, v0, and w0 are the macroscopic velocities. The relationship between them is as follows:

[0069] u′=u-u0 (2)

[0070] v′=v-v0 (3)

[0071] w′=w-w0 (4)

[0072] The statistical mean of random thermal velocity is 0, that is

[0073]

[0074]

[0075]

[0076] Thus there is

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083] Right now

[0084]

[0085] Therefore, the stress tensor at the wall can be determined by simply obtaining the statistical average of the first-order and second-order terms of density and velocity.

[0086] In specific implementation, in the above-mentioned aircraft wall stress tensor sampling method provided in an embodiment of the present invention, the above steps of sampling the first-order terms and second-order terms of the velocity of the simulated molecules can specifically include: using the absolute value of the normal velocity of the simulated molecules as a weight, sampling the first-order term of the incident simulated molecular velocity, the first-order term of the reflected simulated molecular velocity, the second-order term of the incident simulated molecular velocity, and the second-order term of the reflected simulated molecular velocity.

[0087] That is, the absolute value of the normal velocity of the simulated molecules is used as a weight in the sampling of each velocity term at the wall. The stress tensor itself is a three-dimensional "volume" quantity, while the wall flux is a two-dimensional "area" quantity. This means that only the simulated molecules that hit the wall are considered, rather than all the simulated molecules in the unit cell adjacent to the wall. The probability of a simulated molecule hitting the wall per unit time is proportional to the component of its normal velocity perpendicular to the wall. Therefore, if the absolute value of the normal velocity of the simulated molecules is not used as a weight in the sampling, the result will be biased towards the faster simulated molecules. Similar treatment is required in the calculation of the wall slip velocity and jump temperature.

[0088] Specifically, let the number of simulated molecules incident on the wall during the sampling period be N i , the number of simulated molecules reflected from the wall is N r , W F is the simulated molecular weight factor, m is the simulated molecular mass, u i ,v i ,w i is the incident simulated molecule velocity, u r ,v r ,w r is the reflection-simulated molecular velocity, represents the absolute value of the normal component of the incident velocity of the simulated molecule, represents the absolute value of the normal component of the simulated molecular reflection velocity. Then the sampling of each velocity term in (14) can be performed as follows:

[0089] Sampling of the first-order velocity term of incident simulated molecules:

[0090]

[0091] Sampling of the first-order term of molecular velocity in reflection simulation:

[0092]

[0093] Sampling of the second-order terms of the incident simulated molecular velocity:

[0094]

[0095] Sampling of second-order terms in molecular velocities for reflection simulations:

[0096]

[0097] In a specific implementation, in the above-mentioned aircraft wall stress tensor sampling method provided in the embodiment of the present invention, the following formula can be used to calculate the macroscopic velocity:

[0098]

[0099]

[0100]

[0101] In a specific implementation, in the above-mentioned aircraft wall stress tensor sampling method provided in the embodiment of the present invention, the statistical average value of each second-order term of the simulated molecular velocity can be calculated using the following formula:

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108] It should be noted that, with the exception of the density at the wall, the remaining sampling statistics in the stress tensor at the wall are already fully determined. Density is a volumetric quantity, while the wall is an area quantity. Density does not have a direct definition at the wall. Therefore, in a specific implementation, the above-mentioned aircraft wall stress tensor sampling method provided in the embodiment of the present invention may further include, before determining the aircraft wall stress tensor, determining the density at the aircraft wall by equating the normal stress at the aircraft wall with the wall normal momentum flux.

[0109] Specifically, the normal stress at the wall is:

[0110]

[0111] Where n is the wall normal unit vector, and its components are in the form of (n x ,n y ,n z ).

[0112] The wall pressure is defined according to the wall normal momentum flux:

[0113]

[0114] Where Δt is the time step and ΔS is the wall element area.

[0115] The present invention utilizes the equality of the above formulas (24) and (25) to determine the density at the wall and ultimately determine the stress tensor.

[0116] In the present invention, after the stress tensor is determined, the stress vector at the wall can be calculated as P·n, the normal stress is P·n·n, the tangential stress is P·n·τ (τ is the tangential unit vector of the wall), and the static pressure is The wall pressure p includes not only the static pressure p static , also includes the normal component of the force acting on the wall by the viscous stress tensor.

[0117] The following describes the above-mentioned aircraft wall stress tensor sampling method provided by the present invention by taking a two-dimensional hypersonic flow around a cylinder as an example:

[0118] like Figure 2As shown, the cylinder diameter is 0.1524 m, the incoming flow Mach number is 25, the incoming flow Knudsen number is 0.25, the incoming flow density is 1.127e-6 kg / m3, the incoming flow temperature is 200 K, and the wall temperature is 1500 K. The incoming flow is argon.

[0119] The above-mentioned aircraft wall stress tensor sampling method and UGKS method provided by the present invention are used to solve the problem respectively. Among them, UGKS is another kinetic solution method. The wall pressure can also be split into the normal components of static pressure and viscous stress in the UGKS calculation results, which is convenient for comparison with the DSMC results. The flow field pressure distribution is as follows Figure 3 As shown, the wall pressure coefficient is Figure 4 and Figure 5 As shown. Figure 4 and Figure 5 It can be seen that the wall pressure distribution obtained using the aircraft wall stress tensor sampling method provided by this invention agrees well with the UGKS calculation results. This includes not only the total wall pressure but also the static pressure component and the normal component of the viscous stress. Therefore, the aircraft wall stress tensor sampling method provided by this invention provides new insights for improving slip boundary models.

[0120] Based on the same inventive concept, an embodiment of the present invention also provides an aircraft wall stress tensor sampling device. Since the principle of solving the problem by this device is similar to that of the aforementioned aircraft wall stress tensor sampling method, the implementation of this device can refer to the implementation of the aircraft wall stress tensor sampling method, and the repeated parts will not be repeated.

[0121] In specific implementation, the aircraft wall stress tensor sampling device provided by the embodiment of the present invention is as follows: Figure 6 As shown, specifically including:

[0122] The grid generation module 11 is used to generate a computational grid based on the flow of rarefied gas at high altitudes where the aircraft is located;

[0123] A molecule arrangement module 12 is used to randomly distribute simulated molecules within the computational grid; the simulated molecules are used to represent gas molecules;

[0124] The molecular control module 13 is used to simulate the linear motion of the molecule according to the velocity and time step information of the simulated molecule in each iterative time step;

[0125] The tensor sampling module 14 is used to sample the stress tensor of the aircraft wall if the motion trajectory of the simulated molecule hits the aircraft wall.

[0126] In the above-mentioned aircraft wall stress tensor sampling device provided in an embodiment of the present invention, the aircraft wall stress tensor can be sampled through the interaction of the above-mentioned four modules. After obtaining the stress tensor, the decomposition of the force acting on the wall can be realized, which is used for the study of the slip boundary condition model, and further realizes the rapid prediction of the aerodynamic characteristics of the aircraft in a high-altitude and sparse environment.

[0127] For more specific working processes of the above modules, please refer to the corresponding contents disclosed in the above embodiments, which will not be repeated here.

[0128] Correspondingly, an embodiment of the present invention further discloses an aircraft wall stress tensor sampling device, comprising a processor and a memory; wherein, when the processor executes a computer program stored in the memory, it implements the aircraft wall stress tensor sampling method disclosed in the aforementioned embodiment.

[0129] For more specific details about the above method, please refer to the corresponding contents disclosed in the aforementioned embodiments, which will not be described again here.

[0130] Furthermore, the present invention also discloses a computer-readable storage medium for storing a computer program; when the computer program is executed by a processor, the aforementioned aircraft wall stress tensor sampling method is implemented.

[0131] For more specific details about the above method, please refer to the corresponding contents disclosed in the aforementioned embodiments, which will not be described again here.

[0132] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. References to the same or similar portions of the various embodiments will be sufficient. The devices, equipment, and storage media disclosed in the embodiments are described briefly because they correspond to the methods disclosed in the embodiments. For relevant details, refer to the method descriptions.

[0133] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0134] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0135] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0136] The above is a detailed introduction to the aircraft wall stress tensor sampling method, device, equipment and storage medium provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A method for sampling aircraft wall stress tensors, characterized in that: include: Generate a computational grid based on the flow of rarefied gas at high altitudes where the aircraft is located; randomly distributing simulated molecules within the computational grid; Simulated molecules are used to represent gas molecules; In each iterative time step, the linear motion of the simulated molecules is simulated according to the velocity and time step information of the simulated molecules; If the trajectory of the simulated molecule hits the wall of the vehicle, the stress tensor of the vehicle wall is sampled; The process of sampling the aircraft wall stress tensor includes: sampling each first-order term and each second-order term of the simulated molecular velocity; calculating the statistical average of each second-order term of the simulated molecular velocity; and determining the aircraft wall stress tensor based on the density at the aircraft wall and the statistical average of each first-order term and each second-order term of the simulated molecular velocity; The sampling of the first-order and second-order terms of the velocity of the simulated molecules includes: using the absolute value of the normal velocity of the simulated molecules as a weight to sample the first-order term of the incident simulated molecular velocity, the first-order term of the reflected simulated molecular velocity, the second-order term of the incident simulated molecular velocity, and the second-order term of the reflected simulated molecular velocity.

2. The aircraft wall stress tensor sampling method according to claim 1, characterized in that: The first-order term of the incident simulated molecule velocity is sampled using the following expression: 、 、 ； The first-order term of the reflection-simulated molecular velocity is sampled using the following expression: 、 、 ； The second-order terms of the incident simulated molecular velocity are sampled using the following expression: 、 、 、 、 、 ； The second-order term of the reflection-simulated molecular velocity is sampled using the following expression: 、 、 、 、 、 ； in, is the number of simulated molecules incident on the wall during the sampling period, is the number of simulated molecules reflected from the wall, is the simulated molecular weight factor, To simulate molecular mass, is the incident simulated molecular velocity, To simulate molecular velocities for reflection, represents the absolute value of the normal component of the incident velocity of the simulated molecule, Represents the absolute value of the normal component of the reflection velocity of the simulated molecules.

3. The aircraft wall stress tensor sampling method according to claim 2, characterized in that: The statistical average of each second-order term of the simulated molecular velocity is calculated using the following formula: ； ； ； ； ； ； in, 、 、 is the simulated molecular velocity.

4. The aircraft wall stress tensor sampling method according to claim 3, characterized in that: Before determining the aircraft wall stress tensor, the method further includes: The density at the vehicle wall is determined by the equality of the normal stress at the vehicle wall and the normal momentum flux at the wall.

5. The aircraft wall stress tensor sampling method according to claim 4, characterized in that: The following formula is used to determine the vehicle wall stress tensor: ； in, is the vehicle wall stress tensor, is the density, 、 、 Macro speed.

6. An aircraft wall stress tensor sampling device, characterized in that: include: The grid generation module is used to generate a computational grid based on the flow conditions of the rarefied gas at high altitudes where the aircraft is located; a molecule arrangement module for randomly distributing simulated molecules within the computational grid; Simulated molecules are used to represent gas molecules; A molecular control module is used to simulate the linear motion of the molecules according to the velocity and time step information of the simulated molecules in each iterative time step; A tensor sampling module is used to sample the stress tensor of the aircraft wall if the trajectory of the simulated molecule hits the aircraft wall; The process of sampling the aircraft wall stress tensor includes: sampling each first-order term and each second-order term of the simulated molecular velocity; calculating the statistical average of each second-order term of the simulated molecular velocity; and determining the aircraft wall stress tensor based on the density at the aircraft wall, the first-order term of the simulated molecular velocity, and the statistical average of each second-order term; wherein, the sampling of each first-order term and each second-order term of the simulated molecular velocity includes: using the absolute value of the normal velocity of the simulated molecule as a weight, sampling the first-order term of the incident simulated molecular velocity, the first-order term of the reflected simulated molecular velocity, the second-order term of the incident simulated molecular velocity, and the second-order term of the reflected simulated molecular velocity.

7. An aircraft wall stress tensor sampling device, characterized in that: The method comprises a processor and a memory, wherein when the processor executes the computer program stored in the memory, the aircraft wall stress tensor sampling method according to any one of claims 1 to 5 is implemented.

8. A computer-readable storage medium, characterized in that Used to store a computer program, wherein when the computer program is executed by a processor, the aircraft wall stress tensor sampling method according to any one of claims 1 to 5 is implemented.

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