A method for processing the external flow field grid of a missile and related products

Abstract

The present disclosure relates to a method and related products for processing the external flow field mesh of a missile. The method includes: constructing an initial external flow field hexahedral mesh associated with the missile shape; in response to the missile shape being deformed, calculating the deformation characterization factor of the missile shape deformation based on the deformation parameter; using the deformation characterization factor to evaluate the sparsity of the deformed external flow field hexahedral mesh corresponding to the missile shape deformation and obtain an evaluation result; and performing a mesh topology change operation on the initial external flow field hexahedral mesh according to the evaluation result to obtain a transformed external flow field hexahedral mesh. Using the scheme of the present disclosure, the local update of the missile's external flow field mesh can be quickly achieved according to the change of the missile shape, thereby improving the optimization efficiency of the missile's external flow field mesh.

Description

Technical Field

[0001] The present disclosure generally relates to the technical field of missile flight simulation and, more particularly, to a method, device and computer-readable storage medium for processing an external flow field grid of a missile. Background Art

[0002] In the development of spacecraft, real models and experiments are increasingly replaced by digital design and simulation. At present, the most commonly used and effective means of simulating and analyzing spacecraft performance is the finite element method, in which the finite element meshes usually include tetrahedral meshes and hexahedral meshes. In actual application scenarios, compared with tetrahedral meshes, hexahedral meshes have significant advantages in calculation accuracy, anti-distortion degree, convergence speed and storage space. Therefore, the finite element method prefers to use hexahedral meshes to simulate and analyze spacecraft performance. The surface of the spacecraft will deform during flight, so during the simulation process, it is necessary to dynamically change the mesh (such as hexahedral mesh) according to the deformation of the spacecraft surface.

[0003] The mesh topology deformation method is a classic problem in hexahedral mesh optimization, which improves the mesh quality by changing the connection relationship of the hexahedral mesh nodes. Compared with simple geometric optimization, the mesh topology deformation method has greater flexibility. At present, the operations for modifying the topology of hexahedral meshes include flipping operations, atomic operations, and dual operations. However, due to the strong structural constraints, the topology optimization of hexahedral meshes is more difficult. In view of this, how to achieve the topology optimization of hexahedral meshes has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] In order to at least partially solve the technical problems mentioned in the background technology, the solution of the present disclosure provides a solution for processing the outer flow field grid of a missile. Using the solution of the present disclosure, the local update of the outer flow field grid of the missile can be quickly realized, and the optimization efficiency of the outer flow field grid of the missile can be improved. To this end, the present disclosure provides solutions in the following aspects.

[0005] On the one hand, the present disclosure provides a method for processing an external flow field mesh of a missile, comprising: constructing an initial external flow field hexahedral mesh associated with a missile shape; in response to deformation of the missile shape, calculating a deformation characterization factor of the missile shape deformation based on a deformation parameter; using the deformation characterization factor to evaluate the sparsity of the deformed external flow field hexahedral mesh corresponding to the deformation of the missile shape and obtaining an evaluation result; and performing a mesh topology change operation on the initial external flow field hexahedral mesh according to the evaluation result to obtain a transformed external flow field hexahedral mesh.

[0006] In one embodiment, the deformation characterization factor at least includes a rotation angle and a tilt angle.

[0007] In another embodiment, the deformation characterization factor is used to evaluate the sparsity of the deformed external flow field hexahedral mesh corresponding to the deformation of the missile shape and obtain the evaluation result, which includes: calculating the difference in deformation characterization factors corresponding to adjacent characteristic modules on the missile shape; comparing the difference with a preset threshold; and evaluating the sparsity of the external flow field hexahedral mesh after local deformation at the adjacent characteristic modules based on the comparison result of the difference with the preset threshold and obtaining the evaluation result.

[0008] In another embodiment, the sparsity of the locally deformed hexahedral mesh of the external flow field at the adjacent feature module is evaluated based on the comparison result of the difference with a preset threshold and the evaluation result is obtained, including: in response to the difference being greater than the preset threshold, obtaining an evaluation result that the locally deformed hexahedral mesh of the external flow field at the adjacent feature module is sparse; or in response to the difference being less than the preset threshold, obtaining an evaluation result that the locally deformed hexahedral mesh of the external flow field at the adjacent feature module is dense.

[0009] In yet another embodiment, the feature module includes at least a missile rudder.

[0010] In another embodiment, performing a mesh topology change operation on the initial external flow field hexahedral mesh according to the evaluation result to obtain a transformed external flow field hexahedral mesh includes: in response to the evaluation result of the local deformed external flow field hexahedral mesh being sparse, performing a dual addition mesh topology change operation or a mesh topology change operation of adding singular points on the local area corresponding to the initial external flow field hexahedral mesh; or in response to the local deformed external flow field hexahedral mesh being dense, performing a dual deletion mesh topology change operation on the local area corresponding to the initial external flow field hexahedral mesh.

[0011] In yet another embodiment, the method further comprises: geometrically optimizing the transformed external flow field hexahedral mesh according to the geometric features of the missile shape to obtain an optimized external flow field hexahedral mesh.

[0012] In another embodiment, wherein the transformed external flow field hexahedral mesh is geometrically optimized according to the geometric characteristics of the missile shape to obtain the optimized external flow field hexahedral mesh, comprising: establishing a correspondence between points in the deformed area and points outside the deformed area in the transformed external flow field hexahedral mesh; and optimizing the coordinates of the points in the deformed area in the transformed external flow field hexahedral mesh using an interpolation method according to the correspondence and the geometric characteristics of the missile shape to obtain the optimized external flow field hexahedral mesh.

[0013] In another aspect, the present disclosure also provides a device for processing the external flow field grid of a missile, comprising: a processor; and a memory connected to the processor, wherein the memory stores computer program code, and when the computer program code is executed, the processor executes the aforementioned multiple embodiments.

[0014] In yet another aspect, the present disclosure further provides a computer-readable storage medium having stored thereon computer-readable instructions for processing an external flow field grid of a missile, wherein when the computer-readable instructions are executed by one or more processors, the aforementioned multiple embodiments are implemented.

[0015] Through the scheme disclosed in the present invention, the sparseness of the deformed external flow field hexahedral mesh is evaluated by using the deformation characterization factor obtained by the deformation of the missile shape, and the mesh topology change operation is performed on the initial external flow field hexahedral mesh according to the evaluation result, so that the mesh can be quickly updated locally and the mesh optimization efficiency is improved. Furthermore, the embodiment disclosed in the present invention also performs geometric optimization on the transformed external flow field hexahedral mesh, thereby improving the quality of the optimized mesh. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] By reading the following detailed description with reference to the accompanying drawings, the description of the exemplary embodiments of the present disclosure and other objects, features and advantages will become readily understood. In the accompanying drawings, several embodiments of the present disclosure are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0017] Figure 1 is to illustrate the mesh flipping topology operation;

[0018] Figure 2 is to show the mesh dual topology operation;

[0019] Figure 3 is an exemplary flow chart showing a method for processing an outer flow field grid of a missile according to an embodiment of the present disclosure;

[0020] Figure 4 is an exemplary schematic diagram showing construction of an initial external flow field hexahedral mesh according to an embodiment of the present disclosure;

[0021] Figure 5 is an exemplary schematic diagram showing a missile rudder before and after deflection according to an embodiment of the present disclosure;

[0022] Figure 6 is an exemplary schematic diagram showing the corresponding external flow field hexahedral mesh before and after performing a mesh topology change operation according to an embodiment of the present disclosure;

[0023] Figure 7 is an exemplary schematic diagram showing points in a deformation region and points outside the deformation region before and after geometric optimization according to an embodiment of the present disclosure;

[0024] Figure 8 is an exemplary schematic diagram showing the corresponding hexahedral mesh of the external flow field before and after the geometry optimization according to an embodiment of the present disclosure; and

[0025] Fig. 9 is a block diagram showing a device for processing an external flow field grid of a missile according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0026] The principles and spirit of the present disclosure will be described below with reference to several exemplary embodiments. It should be understood that these embodiments are provided only to enable those skilled in the art to better understand and implement the present disclosure, and are not intended to limit the scope of the present disclosure in any way. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0027] As described in the background technology, the current operations for modifying the topology of hexahedral meshes include flipping operations, atomic operations, and dual operations. Among them, flipping operations refer to converting a hexahedral set into a hexahedral set with the same boundaries according to a given template, so that local adjustments of the hexahedral mesh can be realized more easily. Figure 1 The figure shows the flipping operation based on various templates. However, due to the limitation of templates, the flipping operation can only modify specific local topological structures, so it is difficult to be general. In addition, the flipping operation will also generate a large number of singular edges, making it difficult to improve the mesh quality.

[0028] Atomic operations use faces as operation objects, and thus a set of non-degradable atomic operations are proposed. Since a single atomic operation cannot effectively modify the topological structure of a hexahedral mesh, atomic operations must be combined according to certain rules. However, due to the lack of effective combination rules, atomic operations are only in the theoretical research stage. The dual structure of a hexahedral mesh can be regarded as an arrangement of a set of two-dimensional manifold faces. The dual operation is the most direct and effective hexahedral mesh topology modification operation, which uses the layers and columns of the hexahedral mesh as operation objects, such as Figure 2 shown. Figure 2 As shown above, the operation object is the column, that is, the topological structure of the hexahedral mesh is changed by inserting columns. Figure 2 The following shows that the layer is used as the operation object, that is, the topology structure of the hexahedral mesh is changed through layer operations. However, since the hexahedral mesh is subject to strong structural constraints, topology optimization of the hexahedral mesh is more difficult.

[0029] In view of this, in order to overcome the deficiencies in one or more of the above aspects, in an embodiment of the present disclosure, a solution for processing the external flow field grid of a missile is provided to achieve rapid local update of the grid and improve the optimization efficiency of the grid.

[0030] The technical solutions in the embodiments of the present disclosure will be described clearly and completely below in conjunction with the accompanying drawings. It should be understood that the embodiments described in this specification are only some embodiments provided by the present disclosure to facilitate a clear understanding of the solutions and to comply with legal requirements, and are not all embodiments that can implement the present disclosure. Based on the embodiments disclosed in this specification, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present disclosure.

[0031] Figure 3 FIG. 3 is an exemplary flow chart showing a method 300 for processing an outer flow field grid of a missile according to an embodiment of the present disclosure. Figure 3 As shown in, at step S302, an initial external flow field hexahedral mesh associated with the missile shape is constructed. In an implementation scenario, for example, ANSA processing software can be used to construct an initial external flow field hexahedral mesh associated with the missile shape. It can be understood that the aforementioned missile shape can generally be divided into a warhead, a missile body, a missile wing, and a missile rudder. Therefore, when constructing the initial external flow field hexahedral mesh, the external flow field hexahedral meshes can first be constructed for the aforementioned model blocks (such as the warhead, the missile body, the missile wing, and the missile rudder). Then, the external flow field hexahedral meshes of different blocks are spliced ​​to form an initial external flow field hexahedral mesh associated with the missile shape. This will be discussed later in conjunction with Figure 4 Detailed description.

[0032] At step S304, in response to the missile shape deformation, the deformation characterization factor of the missile shape deformation is calculated based on the deformation parameter. In an implementation scenario, it is necessary to simulate different postures of the missile to reflect the aerodynamic coefficients of the missile shape in different forms. The change of the missile shape will cause the missile shape to deform. In one embodiment, the change of the missile shape is determined by the deformation parameter, so the deformation characterization factor of the missile shape deformation can be obtained based on the deformation parameter. In some embodiments, the deformation characterization factor may include but is not limited to the rotation angle and the tilt angle. This will be discussed later in conjunction with Figure 5 Detailed description.

[0033] Based on the deformation characterization factor obtained above, at step S306, the deformation characterization factor is used to evaluate the sparsity of the deformed external flow field hexahedral mesh corresponding to the deformation of the missile shape and obtain an evaluation result. It can be understood that the change of the missile shape will cause the change of its external flow field hexahedral mesh, so the deformation characterization factor can be used to evaluate the sparsity of the deformed external flow field hexahedral mesh and obtain an evaluation result. Specifically, the difference of the deformation characterization factors corresponding to the adjacent feature modules on the missile shape can be calculated first. Then, the difference is compared with the preset threshold, and then the sparsity of the external flow field hexahedral mesh after local deformation at the adjacent feature module is evaluated based on the comparison result of the difference and the preset threshold and the evaluation result is obtained. In one embodiment, when the difference is greater than the preset threshold, the evaluation result that the local deformed external flow field hexahedral mesh at the adjacent feature module is sparse is obtained. When the difference is less than the preset threshold, the evaluation result that the local deformed external flow field hexahedral mesh at the adjacent feature module is dense is obtained. In some embodiments, the aforementioned feature module may include but is not limited to the missile rudder.

[0034] After obtaining the above-mentioned evaluation results, at step S308, a mesh topology change operation is performed on the initial external flow field hexahedral mesh according to the evaluation results to obtain a transformed external flow field hexahedral mesh. In one embodiment, the mesh topology change operation may include a mesh topology change operation of dual addition, dual deletion, or addition of singular points. Specifically, when the locally deformed external flow field hexahedral mesh is sparse, a mesh topology change operation of dual addition or a mesh topology change operation of adding singular points is performed on the local area corresponding to the initial external flow field hexahedral mesh. When the locally deformed external flow field hexahedral mesh is dense, a mesh topology change operation of dual deletion is performed on the local area corresponding to the initial external flow field hexahedral mesh, thereby realizing local update of the external flow field hexahedral mesh.

[0035] Combined with the above description, it can be seen that the embodiment of the present disclosure evaluates the sparsity of the deformed external flow field hexahedral mesh through the deformation characterization factor of the missile shape deformation, and then performs a corresponding mesh topology change operation on the initial external flow field hexahedral mesh according to the evaluation result. Based on this, it is possible to quickly update the mesh locally, which can be applicable to dynamically changing the mesh in the field of missile flight simulation.

[0036] Figure 4 FIG. 1 is an exemplary schematic diagram showing the construction of an initial external flow field hexahedral grid according to an embodiment of the present disclosure. Figure 4The left figure in FIG. 4 shows a missile shape 400, which may include a warhead 401, a body 402, wings 403, and a rudder 404. As previously mentioned, before constructing the initial external flow field hexahedral mesh, the missile may be first divided into model blocks according to the characteristics of the missile shape using, for example, ANSA processing software, and then an external flow field hexahedral mesh may be constructed for each model block, for example Figure 4 Based on the external flow field hexahedral mesh of each model block, the external flow field hexahedral mesh of each model block is further spliced ​​to obtain the initial external flow field hexahedral mesh of the missile shape, for example Figure 4 As shown in the right figure.

[0037] As mentioned above, when simulating different postures of the missile, the missile shape will be deformed, which will correspondingly cause the above-mentioned initial external flow field hexahedral mesh to deform. Therefore, the sparseness of the deformed external flow field hexahedral mesh can be evaluated by the deformation characterization factor, for example, by comparing the difference between the deformation characterization factors corresponding to adjacent feature modules and the preset threshold value to evaluate the sparseness of the locally deformed external flow field hexahedral mesh. Then, the initial external flow field hexahedral mesh is locally updated according to the evaluation results. The following takes the missile rudder as an example of a feature module to describe in detail how to evaluate the sparseness of the deformed external flow field hexahedral mesh through the deformation characterization factor.

[0038] Figure 5 FIG. 2 is an exemplary schematic diagram showing the missile rudder before and after deflection according to an embodiment of the present disclosure. Figure 5 The left figure in FIG. 1 shows the missile rudder 501 (also referred to as the above Figure 4 The left figure shows a schematic diagram of the missile rudder 404 before deflection. Figure 5 The right figure in the figure shows the missile rudder 501 (also referred to as the above Figure 4 The left figure shows a schematic diagram of the deflected rudder 404. It can be understood that Figure 5 Based on the above Figure 4 The left view of the middle left figure is that from the missile body 502 (that is, the above Figure 4 The left figure shows a schematic diagram of the missile rudder before and after deflection obtained by observing the tail of the missile rudder body 402. In an exemplary scenario, assuming that a point p is selected on the missile rudder model, the deflection (or rotation) angle θ of the missile rudder can be calculated by the following formula:

[0039]

[0040] Wherein, v represents the vector from the front point p of the missile rudder to the direction perpendicular to the rotation axis, v′ represents the vector from the rear point p of the missile rudder to the direction perpendicular to the rotation axis, acos(*) represents the arccosine function, and θ represents the deflection (or rotation) angle of the missile rudder, i.e., the deformation characterization factor. In one embodiment, the deformation characterization factors of adjacent missile rudders can be obtained based on formula (1).

[0041] In an exemplary scenario, it is assumed that the magnitudes of the deformation characterization factors (e.g., deflection angles) of two adjacent missile rudders are α and β, respectively, and it is assumed that the angles of the two adjacent missile rudders when rotating clockwise are positive, and the angles when rotating counterclockwise are negative. The absolute value of the difference between the deformation characterization factors of the two adjacent missile rudders is thus obtained as |α-β|. Further, the |α-β| is compared with a preset threshold value ξ, and then the sparsity of the deformed external flow field hexahedral mesh is evaluated according to the comparison result, and an evaluation result is obtained. For example, when the |α-β| is greater than ξ, an evaluation result is obtained that the local deformed external flow field hexahedral mesh at the adjacent missile rudder is sparse, and when the |α-β| is less than ξ, an evaluation result is obtained that the local deformed external flow field hexahedral mesh at the adjacent missile rudder is dense.

[0042] According to the evaluation results obtained above, the mesh topology change operation can be performed on the initial external flow field hexahedral mesh to obtain the transformed (or updated) external flow field hexahedral mesh. Taking the adjacent missile rudder as an example again, when the evaluation result of the local deformed external flow field hexahedral mesh at the adjacent missile rudder is sparse, the mesh topology change operation of adding a dual increase or adding a singular point is performed on the local area corresponding to the initial external flow field hexahedral mesh. When the evaluation result of the local deformed external flow field hexahedral mesh at the adjacent missile rudder is dense, the mesh topology change operation of the dual deletion is performed on the local area corresponding to the initial external flow field hexahedral mesh. In other words, when the locally deformed external flow field hexahedral mesh is sparse, the mesh units are locally added to the initial external flow field hexahedral mesh so that the updated external flow field hexahedral mesh is locally dense. On the contrary, when the locally deformed external flow field hexahedral mesh is dense, the mesh units of the initial external flow field hexahedral mesh are locally deleted, so that the updated external flow field hexahedral mesh is locally sparse, thereby realizing the local update of the external flow field hexahedral mesh.

[0043] It can be understood that in differential geometry, the Gauss-Bonnet theorem is an important statement about the connection between surface graphics (curvature) and topology (Euler characteristic). Among them, the Euler characteristic is a topological invariant denoted by x. The Euler characteristic of a two-dimensional topological polyhedron can be expressed as the following formula:

[0044] x=F-E+V (2)

[0045] Where F represents the number of faces, E represents the number of edges, and V represents the number of points. In one embodiment, it is assumed that M is a compact two-dimensional Riemann manifold. is its boundary. Further, let K be the Gaussian curvature of M, k g for The geodesic curvature of , then the Gauss-Bonnet theorem can be expressed as:

[0046]

[0047] Wherein, dA represents the area element of the surface, ds represents the line element of the boundary of M, and x(M) represents the Euler characteristic of M. According to the Gauss-Bonnet theorem, the number of singular points in the structured grid must appear in pairs. Similarly, the local encrypted grid without destroying the surface foundation of the hexahedral grid also needs to insert singular lines in pairs. Therefore, in an exemplary scenario, the embodiments of the present disclosure can locally modify the hexahedral grid topology structure by inserting the grid topology operation of the singular line pair to realize the local encrypted hexahedral grid, for example Figure 6 shown.

[0048] Figure 6 FIG. 1 is an exemplary schematic diagram showing the corresponding external flow field hexahedral mesh before and after performing the mesh topology change operation according to an embodiment of the present disclosure. Figure 6 The left figure in shows the initial external flow field hexahedral mesh. Figure 6 The middle image and Figure 6 The right figure in shows the updated external flow field hexahedral mesh obtained after performing a mesh topology change operation (such as adding singular lines) on the initial external flow field hexahedral mesh, making the transformed external flow field hexahedral mesh denser.

[0049] It can be understood that the deformation of the missile's shape will cause the deformation of its external flow field hexahedral mesh, which in turn will cause the external flow field hexahedral mesh to cross, for example. Therefore, the disclosed embodiment also proposes a method for optimizing the geometry of the transformed external flow field hexahedral mesh according to the geometric characteristics of the missile's shape, so as to obtain an optimized external flow field hexahedral mesh. Specifically, first, a correspondence between points in the deformed area of ​​the transformed external flow field hexahedral mesh and points outside the deformed area can be established. For example, the points outside the deformed area of ​​the transformed external flow field hexahedral mesh are used as fixed points, thereby establishing a correspondence between the fixed points and the points in the deformed area of ​​the transformed external flow field hexahedral mesh. Next, based on the corresponding relationship and the geometric characteristics of the missile's shape, the coordinates of the points in the deformed area of ​​the transformed external flow field hexahedral mesh are optimized using an interpolation method to obtain an optimized external flow field hexahedral mesh. The following will be combined with Figure 7 The aforementioned optimization process is described in detail.

[0050] Figure 7is an exemplary schematic diagram showing the geometric optimization of points in the deformation region and points outside the deformation region before and after according to an embodiment of the present disclosure. Figure 7 The points in the first row and the last row shown in the left figure represent the points outside the deformation area (i.e., fixed points) in the transformed external flow field hexahedral mesh, and the remaining points represent the points inside the deformation area in the transformed external flow field hexahedral mesh. In an implementation scenario, the points outside the deformation area and the points inside the deformation area are on the same surface, and the dotted line between two adjacent points represents the corresponding relationship. In an exemplary scenario, it is assumed that the points outside the deformation area are represented by v fixi , the point within the deformation area is represented by v n , the corresponding relationship can be expressed as [v fix1 ,v1,v2…v n ,v fix2 ], for example, a set of corresponding points [v fix1 ,v1,v2,v3,v fix2 ]. Similarly, Figure 7 The points in the first row and the last row (corresponding to the front and rear ends of the missile rudder) shown in the middle left figure represent the points outside the deformation area (i.e., fixed points) in the hexahedral mesh of the external flow field after geometric optimization, and the remaining points represent the points in the deformation area in the hexahedral mesh of the external flow field after geometric optimization.

[0051] According to the correspondence between the points outside the deformation region and the points inside the deformation region established above, combined with the geometric features of the missile shape corresponding to each edge, and using the interpolation method to optimize the coordinates of the points inside the deformation region in the transformed external flow field hexahedral grid, the optimized external flow field hexahedral grid can be obtained. Specifically, first, the position coordinates of the nth point in the corresponding relationship can be calculated based on the position of the point outside the deformation region (i.e., the fixed point) in the corresponding relationship. In one embodiment, the position coordinates of the nth point in the corresponding relationship can be calculated by the following formula:

[0052]

[0053] Among them, p(v n ) represents the nth point v n The position coordinates, p(v fix1 ) and p(v fix2 ) represent fixed points v fix1 and v fix2 The position coordinates of , τ represents the number of points in the corresponding relationship.

[0054] According to the above formula (4), the position coordinates of the nth point in the corresponding relationship can be obtained. Then, based on the position coordinates of the nth point and the geometric features of the missile shape, the position coordinates of the points in the deformation area are geometrically optimized using the interpolation method. For example, in an exemplary scenario, it is assumed that the current point is located on a cylindrical surface, that is, the geometric features of the missile shape are cylindrical surfaces, and it is assumed that the radius of the cylindrical surface is r. Furthermore, the position coordinates of the points in the deformation area are geometrically optimized using the interpolation method according to the following formula:

[0055]

[0056] Among them, p′(v n ) represents the point v after geometric optimization n The position coordinates, p(v n ) represents the point v before geometry optimization n The position coordinates, C(v n ) indicates v n The corresponding center of the circle in the cylindrical surface. Based on formula (5), the position coordinates of the points in the optimized deformation area can be obtained, for example Figure 7 Compared with Figure 7 The points shown in the left figure are Figure 7 The points shown in the right figure are relatively uniform, so the quality of the optimized hexahedral mesh of the external flow field is higher than that before the geometry optimization.

[0057] Figure 8 is an exemplary schematic diagram showing the corresponding hexahedral mesh of the external flow field before and after the geometric optimization according to the embodiment of the present disclosure. Figure 8 The left figure in shows the hexahedral mesh of the external flow field without geometry optimization. Figure 8 The middle picture and Figure 8 The right figure in the figure shows the corresponding hexahedral mesh of the external flow field after geometry optimization. It can be seen that the hexahedral mesh of the external flow field after geometry optimization is relatively uniform and has high mesh quality.

[0058] Fig. 9 9 is a block diagram showing a device 900 for processing an outer flow field grid of a missile according to an embodiment of the present disclosure. It is understood that the device implementing the solution of the present disclosure may be a single device (eg, a computing device) or a multifunctional device including various peripheral devices.

[0059] like Fig. 9As shown in , the device of the present disclosure may include a central processing unit or central processing unit ("CPU") 911, which may be a general-purpose CPU, a dedicated CPU, or other information processing and program execution unit. Further, the device 900 may also include a large-capacity memory 912 and a read-only memory ("ROM") 913, wherein the large-capacity memory 912 may be configured to store various types of data, including various missile shape models, algorithm data, intermediate results, and various programs required to run the device 900. The ROM 913 may be configured to store data and instructions required for power-on self-test of the device 900, initialization of various functional modules in the system, drivers for basic input / output of the system, and booting the operating system.

[0060] Optionally, the device 900 may also include other hardware platforms or components, such as the tensor processing unit ("TPU") 914, the graphics processing unit ("GPU") 915, the field programmable gate array ("FPGA") 916, and the machine learning unit ("MLU") 917 shown. It is understood that although a variety of hardware platforms or components are shown in the device 900, they are merely exemplary and not restrictive, and those skilled in the art can add or remove corresponding hardware according to actual needs. For example, the device 900 may only include a CPU, related storage devices, and interface devices to implement the method disclosed in the present invention for processing the outer flow field grid of a missile.

[0061] In some embodiments, in order to facilitate the transmission and interaction of data with an external network, the device 900 of the present disclosure further includes a communication interface 918, so that it can be connected to a local area network / wireless local area network ("LAN / WLAN") 905 through the communication interface 918, and then connected to a local server 906 or to the Internet ("Internet") 907 through the LAN / WLAN. Alternatively or additionally, the device 900 of the present disclosure can also be directly connected to the Internet or a cellular network through the communication interface 918 based on wireless communication technology, such as wireless communication technology based on the third generation ("3G"), the fourth generation ("4G") or the fifth generation ("5G") of the third generation ("3G"), the fourth generation ("4G") or the fifth generation ("5G") of the third generation ("3G") of the third generation ("4G") of the fourth generation ("4G") of the fourth generation ("5 ...

[0062] The peripheral devices of the device 900 may include a display device 902, an input device 903 and a data transmission interface 904. In one embodiment, the display device 902 may include, for example, one or more speakers and / or one or more visual displays, which are configured to perform voice prompts and / or image video display on the processing of the outer flow field grid of the display missile disclosed in the present invention or the final result. The input device 903 may include other input buttons or controls such as a keyboard, a mouse, a microphone, a gesture capture camera, etc., which are configured to receive the input of the numerical value of the simulated missile and / or user instructions. The data transmission interface 904 may include, for example, a serial interface, a parallel interface or a universal serial bus interface ("USB"), a small computer system interface ("SCSI"), a serial ATA, a FireWire ("FireWire"), a PCI Express and a high-definition multimedia interface ("HDMI"), etc., which are configured to transmit and interact with other devices or systems. According to the scheme of the present disclosure, the data transmission interface 904 can receive the outer flow field grid of the missile to be processed from the CT device, and transmit to the device 900 data or results including before and after the grid topology transformation, before and after the geometry optimization, or various other types.

[0063] The CPU 911, mass storage 912, ROM 913, TPU 914, GPU 915, FPGA 916, MLU 917 and communication interface 918 of the device 900 of the present disclosure may be interconnected via a bus 919, and data interaction with peripheral devices may be achieved via the bus. In one embodiment, the CPU 911 may control other hardware components in the device 900 and its peripheral devices via the bus 919.

[0064] Combination of the above Fig. 9 The present invention describes a device for processing the outer flow field grid of a missile that can be used to perform the present invention. It should be understood that the device structure or architecture here is only exemplary, and the implementation method and implementation entity of the present invention are not limited thereto, but can be changed without departing from the spirit of the present invention.

[0065] According to the above description in conjunction with the accompanying drawings, those skilled in the art can also understand that the embodiments of the present disclosure can also be implemented by a software program. Therefore, the present disclosure also provides a computer program product. The computer program product can be used to implement the method for processing the outer flow field grid of a missile described in the present disclosure in conjunction with the accompanying drawings 1-8.

[0066] It should be noted that although the operations of the disclosed method are described in a particular order in the accompanying drawings, this does not require or imply that the operations must be performed in this particular order, or that all the operations shown must be performed to achieve the desired results. On the contrary, the steps depicted in the flow chart can be performed in a different order. Additionally or alternatively, some steps can be omitted, multiple steps can be combined into one step, and / or one step can be decomposed into multiple steps.

[0067] It should be understood that when the terms "first", "second", "third" and "fourth" etc. are used in the claims, the specification and the drawings of the present disclosure, they are only used to distinguish different objects, rather than to describe a specific order. The terms "include" and "comprise" used in the specification and claims of the present disclosure indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections.

[0068] It should also be understood that the terms used in this disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. As used in this disclosure and claims, the singular forms of "a", "an", and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It should also be further understood that the term "and / or" used in this disclosure and claims refers to any combination of one or more of the associated listed items and all possible combinations, including these combinations.

[0069] Although the embodiments of the present disclosure are as described above, the contents are only examples used to facilitate understanding of the present disclosure, and are not intended to limit the scope and application scenarios of the present disclosure. Any technician in the technical field described in the present disclosure may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present disclosure, but the scope of patent protection of the present disclosure shall still be based on the scope defined in the attached claims.

Claims

1. A method for processing an outer flow field grid of a missile, comprising: Constructing the initial external flow field hexahedral mesh associated with the missile shape; In response to the missile shape being deformed, a deformation characterization factor of the missile shape being deformed is calculated based on the deformation parameter, wherein the deformation characterization factor at least includes a rotation angle and a tilt angle; Calculating the difference of deformation characterization factors corresponding to adjacent characteristic modules on the missile shape, wherein the characteristic modules at least include the missile rudder; Comparing the difference with a preset threshold; Based on the comparison result between the difference and the preset threshold, the sparsity of the hexahedral mesh of the external flow field after local deformation at the adjacent characteristic modules is evaluated and an evaluation result is obtained; as well as Performing a mesh topology change operation on the initial external flow field hexahedral mesh according to the evaluation result to obtain a transformed external flow field hexahedral mesh, wherein the mesh topology change operation includes a mesh topology change operation of dual addition, dual deletion or adding a singular point; The mesh topology change operation is performed on the initial external flow field hexahedral mesh according to the evaluation result to obtain a transformed external flow field hexahedral mesh, which includes: In response to the sparseness of the local deformed external flow field hexahedral mesh, performing a dual addition mesh topology change operation or a mesh topology change operation of adding singular points on the local area corresponding to the initial external flow field hexahedral mesh; or In response to the dense hexahedral mesh of the local deformed external flow field, a mesh topology change operation of dual deletion is performed on the local area corresponding to the initial hexahedral mesh of the external flow field.

2. The method according to claim 1, wherein evaluating the sparsity of the hexahedral mesh of the external flow field after local deformation at the adjacent feature modules based on the comparison result of the difference with a preset threshold and obtaining the evaluation result comprises: In response to the difference being greater than the preset threshold, obtaining an evaluation result that the hexahedral mesh of the local deformed external flow field at the adjacent characteristic module is sparse; or In response to the difference being less than the preset threshold, an evaluation result is obtained that the local deformed external flow field hexahedral mesh at the adjacent characteristic modules is dense.

3. The method according to claim 1, further comprising: The transformed external flow field hexahedral mesh is geometrically optimized according to the geometric features of the missile shape to obtain an optimized external flow field hexahedral mesh.

4. The method according to claim 3, wherein the step of geometrically optimizing the transformed external flow field hexahedral mesh according to the geometric features of the missile shape to obtain the optimized external flow field hexahedral mesh comprises: Establishing a correspondence between points in the deformed region and points outside the deformed region in the transformed external flow field hexahedral grid; According to the corresponding relationship and the geometric features of the missile shape, the coordinates of the points in the deformed area of ​​the transformed external flow field hexahedral grid are optimized by using an interpolation method to obtain an optimized external flow field hexahedral grid.

5. A device for processing the outer flow field grid of a missile, comprising: processor; as well as A memory connected to the processor, wherein the memory stores computer program code, and when the computer program code is executed, the processor executes the method according to any one of claims 1 to 4.

6. A computer-readable storage medium storing computer-readable instructions for processing an external flow field grid of a missile, wherein the computer-readable instructions, when executed by one or more processors, implement the method according to any one of claims 1 to 4.

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