Parallel computing method, device and medium for ablation particle wall turbulent statistical moment

Abstract

The application relates to the technical field of aircrafts, and discloses an ablative particle wall turbulent flow statistical moment parallel computing method, equipment and medium, which comprises the following steps: acquiring particle two-phase wall turbulent flow direct numerical simulation data; and respectively obtaining turbulent flow statistical moments and particle statistical moments in a parallel computing manner according to the particle two-phase turbulent flow direct numerical simulation data. In this way, the particle wall turbulent flow statistical moments are quickly and efficiently obtained in parallel computing, have strong compatibility, can be coupled with direct numerical simulation results generated by any particle two-phase turbulent flow software to calculate statistical moments, provide key information for developing a sub-grid model, and fill the blank in the field.

Description

Technical Field

[0001] This invention relates to the field of aircraft technology, and in particular to a parallel calculation method, device and medium for statistical moments of turbulent flow in ablation particle walls. Background Technology

[0002] Under extreme mechanical conditions, ablation occurs at the aircraft nose, with ablated particles entering the downstream boundary layer and disrupting the flow process in the compressible boundary layer, thus affecting the mechanisms of friction and heat flow generation. The lack of understanding of these mechanisms leads to design redundancy in aircraft and prevents the utilization of effective flight paths. Mechanistic analysis using direct numerical simulation software for two-phase wall turbulence with compressible ablated particles is necessary.

[0003] Nevertheless, direct numerical simulation cannot solve industrial problems and can only be used for academic research. The fundamental reason is that direct numerical simulation requires a huge computing grid, which is beyond the capacity of modern supercomputing resources and technology.

[0004] Because direct numerical simulations of real-world industrial problems are computationally intensive, designing industrial software requires developing subgrid models of particulate two-phase flow. Statistical moments of particulate two-phase turbulence provide a direct numerical simulation database for establishing these subgrid models. However, currently, there is no technology available for the rapid, efficient, and parallel computation of these statistical moments.

[0005] Therefore, how to quickly and efficiently calculate the statistical moments of particle two-phase flow in parallel is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide a parallel calculation method, device, and medium for the statistical moments of turbulent flow in ablated particle walls, which can quickly and efficiently calculate the statistical moments of two-phase flow in particles in parallel, and has strong compatibility. The specific solution is as follows:

[0007] A parallel calculation method for statistical moments of turbulent flow in ablation particle walls includes:

[0008] Obtain direct numerical simulation data of turbulent flow through a two-phase wall of particles;

[0009] Based on the direct numerical simulation data of the two-phase turbulence of particles, the turbulence statistical moments and particle statistical moments are obtained by parallel computing.

[0010] Preferably, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, the turbulent statistical moments and particle statistical moments are obtained respectively by parallel calculation based on the direct numerical simulation data of particle two-phase turbulence, including:

[0011] Based on the direct numerical simulation data of the two-phase turbulence of the particles, the first-order statistical moments and the second-order statistical moments of the turbulence were calculated.

[0012] Meanwhile, based on the direct numerical simulation data of the two-phase turbulence of the particles, the particle phase is projected into the Euler coordinate system, and the first-order statistical moments and second-order statistical moments of the particles are calculated.

[0013] Preferably, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, the first-order statistical moments of turbulence are calculated using the following formula:

[0014]

[0015]

[0016] Among them, <V px > represents the average flow velocity of the fluid, <V py > represents the average normal velocity of the fluid, <V pz > represents the average spanwise velocity of the fluid, <T> represents the average temperature of the fluid, and N represents the number of fluid samples.

[0017] Preferably, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, the second-order statistical moments of turbulence are calculated using the following formula:

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[0027] Among them, <V pxx >, <V pxy >, <V pxz >, <V pyx >, <V pyy >, <V pyz >, <V pzx >, <V pzy >, <V pzz > These are the nine quantities of the second-order statistical moments of turbulence.

[0028] Preferably, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, the first-order statistical moments of the particles are calculated using the following formula:

[0029]

[0030]

[0031]

[0032] Where <C'> is the particle concentration, <V px '>' represents the average flow velocity of particles, and <V py '>' represents the average normal velocity of the particle, and <V pz '>' represents the average spanwise velocity of the particles, and <T p '> is the average temperature of the particles, and N' is the number of particles sampled.

[0033] Preferably, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, the second-order statistical moments of the particles are calculated using the following formula:

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[0042]

[0043] Among them, <V pxx >, <V pxy >, <V pxz >, <V pyx >, <V pyy >, <V pyz >, <V pzx >, <V pzy >, <V pzz '> represents nine quantities of the second-order statistical moments of the particles.

[0044] Preferably, the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention further includes:

[0045] The turbulent statistical moments and the particle statistical moments are reduced using the MPI parallel reduction method.

[0046] This invention also provides an electronic device, including a processor and a memory, wherein the processor executes a computer program stored in the memory to implement the parallel calculation method for turbulent statistical moments of ablation particle walls as described above in this invention.

[0047] This invention also provides a computer-readable storage medium for storing a computer program, wherein the computer program, when executed by a processor, implements the parallel calculation method for turbulent statistical moments of ablation particle walls as described in this invention.

[0048] As can be seen from the above technical solution, the parallel calculation method for turbulent statistical moments of ablation particle walls provided by the present invention includes: acquiring direct numerical simulation data of turbulent two-phase particle walls; and obtaining turbulent statistical moments and particle statistical moments respectively by parallel calculation based on the direct numerical simulation data of turbulent two-phase particle walls.

[0049] The parallel calculation method for turbulent statistical moments of ablation particle walls provided by this invention obtains turbulent statistical moments and particle statistical moments separately by using parallel calculation based on direct numerical simulation data of particle two-phase turbulence. This method provides fast and efficient parallel calculation of particle wall turbulent statistical moments, has strong compatibility, and can be coupled with the direct numerical simulation results generated by any particle two-phase turbulence software to calculate statistical moments. This provides key information for the development of subgrid models and fills a gap in this field.

[0050] Furthermore, this invention also provides a corresponding device and computer-readable storage medium for the parallel calculation method of turbulent statistical moments of ablation particle walls, further making the above method more practical. The device and computer-readable storage medium have corresponding advantages. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0052] Figure 1 A flowchart of the parallel calculation method for turbulent statistical moments of ablation particle walls provided in an embodiment of the present invention;

[0053] Figure 2 A schematic diagram of the particle turbulence statistical moment problem extracted from engineering, provided for an embodiment of the present invention;

[0054] Figure 3 A schematic diagram corresponding to the parallel calculation method for turbulent statistical moments of ablation particle walls provided in an embodiment of the present invention;

[0055] Figure 4 This is a schematic diagram of the solution process of the turbulence statistical moment solver provided in an embodiment of the present invention;

[0056] Figure 5 This is a schematic diagram of the solution process of the particle statistical moment solver provided in an embodiment of the present invention;

[0057] Figure 6 A schematic diagram of the statistical moment sampling region of an arbitrary interface of a computational domain that evolves along space, provided in an embodiment of the present invention;

[0058] Figure 7 This is a schematic diagram of the parallel reduction process of particle or turbulent statistical moments (MPI) provided in an embodiment of the present invention. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] This invention provides a parallel calculation method for the statistical moments of turbulent flow in ablated particle walls, such as... Figure 1 As shown, it includes the following steps:

[0061] S101. Obtain direct numerical simulation data of turbulent two-phase wall granular flow;

[0062] Specifically, any compressible ablation particle two-phase wall turbulence solver can be used to obtain direct numerical simulation data of particle two-phase wall turbulence.

[0063] S102. Based on the direct numerical simulation data of particle two-phase turbulence, the turbulence statistical moments and particle statistical moments are obtained by parallel computing.

[0064] It should be noted that the above-mentioned turbulent statistical moments and particle statistical moments can be understood as the various orders of turbulent statistical moments of the dispersed particle phase and the fluid-carrying phase in the turbulent flow of compressible particle walls.

[0065] In the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, based on the direct numerical simulation data of particle two-phase turbulence, the turbulent statistical moments and particle statistical moments are obtained by parallel calculation. This method can quickly and efficiently calculate the turbulent statistical moments of particle walls, has strong compatibility, and can be coupled with the direct numerical simulation results generated by any particle two-phase turbulence software to calculate the statistical moments. This provides key information for the development of subgrid models and fills a gap in this field.

[0066] Figure 2 A numerical model of an outflowing aircraft with an ablation particle boundary layer is presented. Generally, the engineering problem can be summarized as: A) spatially evolving boundary layer particle turbulence; B) statistically steady near-wall turbulence model. Establishing a subgrid-like particle turbulence model requires extracting turbulence statistical moments from the direct numerical simulation databases of models A and B.

[0067] Furthermore, in a specific implementation, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the above-mentioned embodiment of the present invention, step S102 obtains the turbulent statistical moments and particle statistical moments respectively by parallel calculation based on the direct numerical simulation data of particle two-phase turbulence. Specifically, it may include: calculating the first-order and second-order turbulent statistical moments based on the direct numerical simulation data of particle two-phase turbulence; and simultaneously, projecting the particle phase onto the Euler coordinate system based on the direct numerical simulation data of particle two-phase turbulence to calculate the first-order and second-order particle statistical moments.

[0068] Specifically, such as Figure 3 As shown, direct numerical simulation data of particle two-phase turbulence can include information such as particle-fluid two-phase density, velocity, and temperature generated by a compressible ablative particle two-phase wall turbulence solver. The first-order and second-order statistical moments of turbulence are calculated using a turbulence statistical moment solver; the specific process is detailed in [link to documentation]. Figure 4 The particle statistical moment solver is used to calculate the first and second order statistical moments of particles. See [link to details]. Figure 5 It is important to emphasize that the dispersed particle phase is based on the Lagrange coordinate system and needs to be projected onto the Eulerian coordinate system to perform the statistical averaging algorithm.

[0069] In specific implementation, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, the first-order statistical moments of turbulence are calculated using the following formula:

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[0072] Among them, <V px > represents the average flow velocity of the fluid, <V py > represents the average normal velocity of the fluid, <Vpz > represents the average spanwise velocity of the fluid, <T> represents the average temperature of the fluid, and N represents the number of fluid samples. In other words, the average velocity of the fluid phase can be calculated using the above formula, including the flow-direction, normal-direction, and spanwise pulsating velocities.

[0073] In specific implementation, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, the second-order statistical moments of turbulence are calculated using the following formula:

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[0083] Among them, <V pxx >, <V pxy >, <V pxz >, <V pyx >, <V pyy >, <V pyz >, <V pzx >, <V pzy >, <V pzz > These are the nine quantities of the second-order statistical moments of turbulence.

[0084] In specific implementation, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, the first-order statistical moments of particles are calculated using the following formula:

[0085]

[0086]

[0087]

[0088] Where <C'> is the particle concentration, <V px '>' represents the average flow velocity of particles, and <V py '>' represents the average normal velocity of the particle, and <Vpz '>' represents the average spanwise velocity of the particles, and <T p '>' represents the average temperature of the particles, and N' represents the number of particles sampled. In other words, the average velocity of the dispersed particle phase, including flow-direction, normal-direction, and spanwise pulsating velocities, can be calculated using the above formula.

[0089] In specific implementation, in the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the embodiments of the present invention, the second-order statistical moments of particles are calculated using the following formula:

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[0099] Among them, <V pxx >, <V pxy >, <V pxz >, <V pyx >, <V pyy >, <V pyz >, <V pzx >, <V pzy >, <V pzz '> represents nine quantities of the second-order statistical moments of the particles.

[0100] In specific implementation, the parallel calculation method for turbulent statistical moments of ablation particle walls provided in the above embodiments of the present invention may further include: using MPI parallel reduction to reduce the turbulent statistical moments and particle statistical moments.

[0101] It should be noted that the statistical moment calculation method is based on parallel computing, which is tens of thousands of times faster than conventional post-processing methods. Figure 6 and Figure 7 A parallel MPI reduction technique for particle or turbulent statistical moments is presented. This technique achieves post-processing speeds tens of thousands of times faster than conventional serial post-processing software. For example... Figure 6As shown, statistical moments can be the entire computational domain or sampling sections within the computational domain: sampling region 1, sampling region 2, and sampling region 3. Given the sampling regions, reduction techniques are needed, such as... Figure 7 As shown, the functional profile f(y) of the normal vector Y is obtained from the original three-dimensional objective function f(x,y,z). That is, the objective function f(x,y,z) is reduced to f(x,y), and then reduced to f(y), which is the statistical moment of the normal section.

[0102] Accordingly, embodiments of the present invention also disclose an electronic device, including a processor and a memory; wherein, when the processor executes a computer program stored in the memory, it implements the parallel calculation method for turbulent statistical moments of ablation particle walls disclosed in the foregoing embodiments.

[0103] For a more detailed explanation of the above method, please refer to the relevant content disclosed in the foregoing embodiments, which will not be repeated here.

[0104] 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, it implements the aforementioned parallel calculation method for the statistical moments of turbulent flow in ablation particle walls.

[0105] For more detailed information on the above methods, please refer to the relevant content disclosed in the foregoing embodiments, which will not be repeated here.

[0106] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the devices and storage media disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0107] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can 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.

[0108] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0109] In summary, the present invention provides a parallel calculation method for turbulent statistical moments of ablated particle walls, comprising: acquiring direct numerical simulation data of turbulent two-phase particle walls; and obtaining turbulent statistical moments and particle statistical moments respectively through parallel calculation based on the direct numerical simulation data of turbulent two-phase particle walls. This method provides fast and efficient parallel calculation of turbulent statistical moments of particle walls, exhibits strong compatibility, and can be coupled with direct numerical simulation results generated by any particle two-phase turbulence software to calculate statistical moments, providing crucial information for the development of subgrid models and filling a gap in this field. Furthermore, the present invention also provides corresponding equipment and computer-readable storage media for the parallel calculation method of turbulent statistical moments of ablated particle walls, further enhancing the practicality of the method. These equipment and computer-readable storage media offer corresponding advantages.

[0110] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0111] The foregoing has provided a detailed description of the parallel calculation method, equipment, and medium for turbulent statistical moments of ablation particle walls provided by this invention. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A parallel calculation method for statistical moments of turbulent flow in ablation particle walls, characterized in that, include: Acquire direct numerical simulation data of particle two-phase wall turbulence; the direct numerical simulation data of particle two-phase turbulence includes information on the density, velocity and temperature of the two phases of the particle fluid generated by the compressible ablation particle two-phase wall turbulence solver. Based on the direct numerical simulation data of the two-phase turbulence of particles, the turbulence statistical moments and particle statistical moments are obtained by parallel computing; among them, the first-order and second-order statistical moments of turbulence are calculated using a turbulence statistical moment solver. The first-order statistical moments of turbulence are calculated using the following formula: ； in, It is the average flow velocity of the fluid. It is the fluid's average normal velocity. It is the average spanwise velocity of the fluid. It is the average temperature of the fluid. N This refers to the number of fluid samples taken. The second-order statistical moments of turbulence are calculated using the following formula: ； ； ； ； ； ； ； ； ； in, These are the nine quantities of the second-order statistical moments of turbulence; Simultaneously, the particle phase is projected into the Euler coordinate system, and the first-order and second-order statistical moments of the particles are calculated using the particle statistical moment solver.

2. The parallel calculation method for statistical moments of turbulent flow in ablation particle walls according to claim 1, characterized in that, The first-order statistical moments of particles are calculated using the following formula: ； in, It's particle concentration. It is the average flow velocity of the particles. It is the average normal velocity of the particle. It is the average spanwise velocity of the particles. It is the average temperature of the particles. This refers to the number of particles sampled.

3. The parallel calculation method for statistical moments of turbulent flow in ablation particle walls according to claim 2, characterized in that, The second-order statistical moments of particles are calculated using the following formula: ； ； ； ； ； ； ； ； ； in, These are the nine quantities of the second-order statistical moments of the particles.

4. The parallel calculation method for statistical moments of turbulent flow in ablation particle walls according to claim 3, characterized in that, Also includes: The turbulent statistical moments and the particle statistical moments are reduced using the MPI parallel reduction method.

5. An electronic device, characterized in that, It includes a processor and a memory, wherein the processor executes a computer program stored in the memory to implement the parallel calculation method for turbulent statistical moments of ablation particle walls as described in any one of claims 1 to 4.

6. A computer-readable storage medium, characterized in that, Used to store a computer program, wherein the computer program, when executed by a processor, implements the parallel calculation method for statistical moments of turbulent ablation of particle walls as described in any one of claims 1 to 4.

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