Flow field determination method, apparatus, device, and medium

Abstract

The application provides a flow field determination method, device, equipment and medium. The method comprises the following steps: modeling a multiphase flow region based on an overall region parameter and a first grid size to generate an overall fluid mechanics model; the overall fluid mechanics model comprises a plurality of first grids; obtaining overall flow field information of the overall fluid mechanics model; determining a local region comprising a target component from the multiphase flow region, modeling the local region based on a local region parameter and a second grid size to generate a local fluid mechanics model; the local fluid mechanics model comprises a plurality of second grids; the second grid size is smaller than the first grid size; obtaining local flow field information of the local fluid mechanics model based on the overall flow field information; and determining target flow field information of the multiphase flow region based on the overall flow field information and the local flow field information, so that the overall flow on a large scale and the fine flow of a local region are efficiently determined, and the requirements of efficiency and accuracy are met.

Description

Technical Field

[0001] This application relates to the field of fluid mechanics, and more specifically, to a method, apparatus, device, and medium for determining a flow field. Background Technology

[0002] In the field of Computational Fluid Dynamics (CFD), which studies the laws of fluid motion and its interaction with surrounding objects, flow field information is a core research object. Its accuracy directly determines the rationality of related engineering designs, the safety of operation, and the reliability of research conclusions. Only by accurately determining the flow field information can a solid foundation be laid for subsequent theoretical analysis, numerical simulation, and engineering practice, and design errors or engineering risks caused by information deviations be avoided.

[0003] In determining flow field information, the computational domain is often divided into meshes. However, using a large mesh size may affect the accuracy of the results, while using a small mesh size may affect processing efficiency. Summary of the Invention

[0004] In view of this, this application provides a flow field determination method, apparatus, device and medium that balances efficiency and accuracy requirements by constructing fluid dynamics models with different grid sizes.

[0005] Specifically, this application is implemented through the following technical solution: According to a first aspect of this application, a method for determining a flow field is provided, the method comprising: Collect overall region parameters of the multiphase flow region, and model the multiphase flow region based on the overall region parameters and the first grid size to generate an overall fluid dynamics model; the overall fluid dynamics model includes multiple first grids; The overall fluid dynamics model is subjected to transient multiphase flow simulation to obtain the overall flow field information of the overall fluid dynamics model; A local region including the target component is determined from the multiphase flow region, local region parameters are collected, and the local region is modeled based on the local region parameters and a second grid size to generate a local hydrodynamic model; the local hydrodynamic model includes multiple second grids; the size of the second grid is smaller than the size of the first grid. Based on the overall flow field information, transient multiphase flow simulation is performed on the local hydrodynamic model to obtain the local flow field information of the local hydrodynamic model; Based on the overall flow field information and the local flow field information, the target flow field information of the multiphase flow region is determined.

[0006] In one optional implementation, the method further includes: During the generation of the overall fluid dynamics model, if the deviation between the size of any component in any dimension and the size of the component in other dimensions is greater than a first preset threshold, the size of the component in that dimension is determined to be 0.

[0007] In one optional implementation, the method further includes: During the generation of the overall fluid dynamics model, if the ratio of the size of any component in any dimension to the size of the first mesh is less than a second preset threshold, and the region where the component is located can be represented by the corresponding target region or the boundary where the component is located can be represented by the corresponding target boundary, the region where the component is located is determined according to the corresponding target region or the boundary where the component is located is determined according to the corresponding target boundary. The target region and the target boundary are used to indicate the addition of a drag term.

[0008] In one optional implementation, determining the local region including the target component from the multiphase flow region includes: Based on the location of the target component in the multiphase flow region and the overall flow field information, a local region including the target component is determined.

[0009] In one optional implementation, determining the local region including the target component based on the location of the target component in the multiphase flow region and the overall flow field information includes: Based on the overall flow field information, the boundary length of the local region is determined; The local region is determined based on the location of the center point of the target component in the multiphase flow region and the boundary length.

[0010] In one optional implementation, the step of performing transient multiphase flow simulation processing on the local hydrodynamic model based on the overall flow field information to obtain the local flow field information of the local hydrodynamic model includes: Determine the target boundary of the local fluid dynamics model, wherein the target boundary is the boundary of the local fluid dynamics model that is located inside the global fluid dynamics model; Based on the flow field information corresponding to the target boundary in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined; Based on the flow field information corresponding to the target boundary in the local fluid dynamics model, transient multiphase flow simulation is performed on the local region other than the target boundary to determine the local flow field information.

[0011] In one optional implementation, the overall flow field information includes the flow field information of each first grid at each time point within the target time period; The step of determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information corresponding to the target boundary in the overall fluid dynamics model includes: Based on the flow field information of each first grid at each time point within the target time period, the flow field information of the target boundary at each time point within the target time period is determined in the overall fluid dynamics model. For each time point in the target time period, based on the flow field information of the target boundary at the associated time point in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0012] In one optional implementation, the overall flow field information includes the flow field information of each first grid at each time point within the target time period; The step of determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information corresponding to the target boundary in the overall fluid dynamics model includes: Based on the flow field information of each first grid at each time point within the target time period, the flow field information of the local region at each time point within the target time period in the overall fluid dynamics model is determined. For the first time point in the target time period, the preset flow field information is determined as the flow field information corresponding to the target boundary in the local hydrodynamic model; For each non-first time point in the target time period, based on the local flow field information of that time point determined in the previous time step, and the flow field information of the local region in the overall fluid dynamics model at each time point in the target time period, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0013] In one optional implementation, determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the local flow field information determined at the previous time step and the flow field information of the local region at various time points within the target time period in the overall fluid dynamics model includes: From the flow field information of the local region in the overall fluid dynamics model at each time point, determine the flow field information of the target time point that satisfies the preset conditions as the local flow field information of the time point determined in the previous time step at that time point; Based on the flow field information of the local region in the overall fluid dynamics model at the target time point, the flow field information of the target boundary in the overall fluid dynamics model at the target time point is determined; Based on the flow field information of the target boundary at the target time point in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0014] In one optional implementation, the preset conditions include: The target fluid phase has a consistent volume within the local area, or the target fluid phase has a consistent volume distribution at the target boundary.

[0015] In one optional implementation, determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information of the target boundary at the target time point in the overall fluid dynamics model includes: Interpolation processing is performed on the flow field information of the target boundary at the target time point in the overall fluid dynamics model to obtain the flow field information of the target boundary in the local fluid dynamics model.

[0016] In one optional implementation, determining the target flow field information of the multiphase flow region based on the overall flow field information and the local flow field information includes: The target flow field information of the multiphase flow region is obtained by replacing the flow field information corresponding to the local region in the overall flow field information with the local flow field information.

[0017] According to a second aspect of this application, a flow field determining apparatus is provided, the apparatus comprising: The first modeling module is used to collect the overall region parameters of the multiphase flow region, and to model the multiphase flow region based on the overall region parameters and the first grid size to generate an overall fluid dynamics model; the overall fluid dynamics model includes multiple first grids; The first processing module is used to perform transient multiphase flow simulation processing on the overall fluid dynamics model to obtain the overall flow field information of the overall fluid dynamics model; The second modeling module is used to determine a local region including the target component from the multiphase flow region, collect local region parameters of the local region, and model the local region based on the local region parameters and a second grid size to generate a local fluid dynamics model; the local fluid dynamics model includes multiple second grids; the size of the second grid is smaller than the size of the first grid. The second processing module is used to perform transient multiphase flow simulation processing on the local hydrodynamic model based on the overall flow field information to obtain the local flow field information of the local hydrodynamic model. The flow field determination module is used to determine the target flow field information of the multiphase flow region based on the overall flow field information and the local flow field information.

[0018] According to a third aspect of this application, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the flow field determination method described in the first aspect above.

[0019] According to a fourth aspect of this application, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps of the flow field determination method described in the first aspect above.

[0020] The flow field determination method, apparatus, equipment, and medium provided in this application construct fluid dynamics models of different scales and ranges. The grid size within each model is adapted to the overall size of the model, thereby controlling the number of grids. First, a larger-sized grid is used to quickly determine the overall flow field information, and then a smaller-sized grid is used to determine the local flow field information at the target component. By determining the flow field information at different scales step by step, the impact of global fine grid on processing efficiency is avoided, while ensuring high fidelity in local areas. This achieves efficient determination of large-scale overall flow and local fine flow, while meeting the requirements of efficiency and accuracy.

[0021] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and are not intended to limit the technical solutions of this disclosure.

[0022] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0023] Figure 1 This is a flowchart illustrating a flow field determination method according to an exemplary embodiment of this application; Figure 2 This is a schematic diagram illustrating an overall fluid dynamics model and a local fluid dynamics model according to an exemplary embodiment of this application; Figure 3 This is a schematic diagram illustrating a flow field information transmission according to an exemplary embodiment of this application; Figure 4 This is a schematic diagram illustrating a flow field determination process according to an exemplary embodiment of this application; Figure 5This is a schematic diagram of a flow field determination device shown in an exemplary embodiment of this application; Figure 6 This is a schematic diagram of the structure of a computer device shown in an exemplary embodiment of this application. Detailed Implementation

[0024] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0025] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0026] It should be understood that although the terms first, second, third, etc., may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0027] Research has shown that determining flow field information often requires meshing the computational domain, and the mesh size directly affects the accuracy and efficiency of the processing results. However, choosing a large mesh size may significantly weaken the ability to capture flow field details, easily leading to numerical deviations or missing key flow phenomena, thus affecting the accuracy of the results. Conversely, using a small mesh size will cause a surge in the number of meshes, consuming more memory, increasing computational load, prolonging processing time, and impacting processing efficiency. Therefore, finding a balance between efficiency and accuracy requirements is a problem that urgently needs to be solved.

[0028] Based on the above research, this application provides a flow field determination method, apparatus, equipment and medium. By constructing fluid dynamics models of different scales and ranges, flow field information at different scales is determined step by step, thereby achieving efficient determination of overall flow at large scales and fine flow in local areas, while meeting the requirements of efficiency and accuracy.

[0029] To facilitate understanding of this embodiment, a detailed description of the flow field determination method disclosed in this application embodiment is provided first. The execution entity of the flow field determination method provided in this application embodiment is generally an electronic device with a certain computing power. This electronic device can be a server, which can be an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud storage, big data, and artificial intelligence platforms. In some possible implementations, this flow field determination method can be implemented by a processor calling computer-readable instructions stored in memory.

[0030] The following description, in conjunction with the accompanying drawings, illustrates a flow field determination method provided by an embodiment of this application.

[0031] See Figure 1 The diagram shown is a flowchart illustrating a flow field determination method according to an exemplary embodiment of this application. Figure 1 As shown in the figure, the flow field determination method provided in this embodiment includes steps S101 to S105, wherein: S101: Collect the overall region parameters of the multiphase flow region, and model the multiphase flow region based on the overall region parameters and the first grid size to generate an overall fluid dynamics model; the overall fluid dynamics model includes multiple first grids.

[0032] Here, when collecting the overall regional parameters of the multiphase flow region, specific data such as the inlet, outlet, and boundary of the multiphase flow region can be collected.

[0033] The multiphase flow refers to the flow of a mixture of substances in which two or more phases coexist, such as concrete.

[0034] For example, taking concrete as an example, when collecting the overall regional parameters of the concrete flow area, specific parameters such as the concrete pouring inlet, air outlet, and boundary can be collected.

[0035] Optionally, the first grid size can be determined based on the size of the multiphase flow region.

[0036] In some possible implementations, the method further includes: During the generation of the overall fluid dynamics model, if the deviation between the size of any component in any dimension and the size of the component in other dimensions is greater than a first preset threshold, the size of the component in that dimension is determined to be 0.

[0037] Here, in the process of modeling the overall fluid dynamics model, local small-scale features are ignored. When the size of any component in a certain dimension differs from the overall size of the component by a certain number, the size of the component in that dimension can be determined as 0.

[0038] For example, stiffening ribs without openings can be simplified to walls with zero thickness. As another example, if the thickness of a steel plate is in the millimeter range, while the dimensions of the component in other dimensions are in the meter range, the thickness can be set to 0, and the steel plate can be simplified to a plane during modeling. Yet another example: if the overall dimensions of a steel plate are in the meter range, and there are millimeter-level protrusions and / or depressions on a certain surface of the steel plate, the depth of the protrusions and depressions can be set to 0, and that surface of the steel plate can be simplified to a smooth surface during modeling.

[0039] The specific value of the first preset threshold can be determined according to the actual needs of generating the overall fluid dynamics model, and is not specifically limited here.

[0040] In this way, when generating the overall fluid dynamics model, the dimensions of component features whose dimensions differ significantly from those of the other dimensions are reduced to zero. This allows small local features to be ignored during geometric modeling, thus assisting in the construction of the overall fluid dynamics model with a large mesh and ensuring the overall mesh quality and generation efficiency.

[0041] In some possible implementations, the method further includes: During the generation of the overall fluid dynamics model, if the ratio of the size of any component in any dimension to the size of the first mesh is less than a second preset threshold, and the region where the component is located can be represented by the corresponding target region or the boundary where the component is located can be represented by the corresponding target boundary, the region where the component is located is determined according to the corresponding target region or the boundary where the component is located is determined according to the corresponding target boundary. The target region and the target boundary are used to indicate the addition of a drag term.

[0042] In the above steps, during the overall fluid dynamics modeling process, adjustments can be made directly when modeling a large area.

[0043] For example, the area containing densely reinforced concrete can be modeled as a porous medium region. This porous medium region can simulate the densely reinforced area of ​​a solid structure. The impediment effect of the porous medium region and the dense reinforcement on concrete flow is equivalent. The reinforcing steel and the surrounding air within this region are considered as a single entity. Here, the porous medium region serves as a region condition that increases the resistance term. As another example, the boundary of a plate with flow holes can be modeled as a porous pressure jump surface. Here, the porous pressure jump surface serves as a boundary condition that increases the resistance term.

[0044] In this way, modeling is done directly based on the target region conditions and target boundary conditions, avoiding direct modeling of small-sized components, and thus avoiding the use of small-scale meshes when generating the overall fluid dynamics model.

[0045] For example, see Figure 2 , Figure 2 This is a schematic diagram illustrating a global fluid dynamics model and a local fluid dynamics model, as shown in an exemplary embodiment of this application. Figure 2 As shown, the multiphase flow region is modeled to generate an overall fluid dynamics model 10, which includes multiple first grids.

[0046] S102: Perform transient multiphase flow simulation on the overall fluid dynamics model to obtain the overall flow field information of the overall fluid dynamics model.

[0047] In this step, the overall fluid dynamics model can be subjected to transient multiphase flow simulation, for example, by using the finite volume method, to obtain the overall flow field information of the overall fluid dynamics model.

[0048] The overall flow field information may include the flow field information of each first grid at various time points within the target time period. The flow field information of a certain first grid at each time point includes, but is not limited to, pressure, velocity, and phase volume fraction. Here, the phase volume fraction is used to indicate the ratio between the volume of each fluid phase and the total volume within the first grid. For example, taking multiphase flow as an air-liquid concrete two-phase flow as an example, if concrete occupies 30% of the volume in a grid, then the concrete phase volume fraction of this grid is 0.3, and the air phase volume fraction is 0.7.

[0049] S103: Determine a local region including the target component from the multiphase flow region, collect local region parameters of the local region, and model the local region based on the local region parameters and the second grid size to generate a local hydrodynamic model; the local hydrodynamic model includes multiple second grids; the size of the second grid is smaller than the size of the first grid.

[0050] In the above steps, for the target component in the multiphase flow region that requires refined flow field information determination, a local region including the target component is determined, and then the local region parameters are collected. Based on the local region parameters and the second grid size, the local region is modeled to generate a local hydrodynamic model.

[0051] In some possible implementations, determining the local region including the target component from the multiphase flow region includes: Based on the location of the target component in the multiphase flow region and the overall flow field information, a local region including the target component is determined.

[0052] In this step, a local region including the target component can be determined based on the position of the target component in the multiphase flow region and the overall flow field information.

[0053] In this way, when delineating local areas, by combining the position of the target component in the multiphase flow region with the obtained overall flow field information, the flow-sensitive area and geometrically critical area can be dynamically identified, thereby accurately defining the local area and avoiding information redundancy or omission caused by traditional experience-based area trimming.

[0054] In some possible implementations, determining the local region including the target component based on the location of the target component in the multiphase flow region and the overall flow field information includes: Based on the overall flow field information, the boundary length of the local region is determined; The local region is determined based on the location of the center point of the target component in the multiphase flow region and the boundary length.

[0055] In the above steps, the boundary length of the local region can be determined based on the overall flow field information, and then the local region can be determined by combining the position of the center point of the target component in the multiphase flow region.

[0056] In this way, the boundary length of the local region is adaptively calculated based on the overall flow field information, and then the local region is delineated according to the boundary length scale with the center point of the target component as the reference. This enables the local region to accurately match the range of changes in the overall flow field information, which helps to improve the accuracy of the local flow field information.

[0057] Optionally, when collecting local parameters of the local area, actual data of the local area can be collected, such as boundary data, data of reinforcing bars, and connectors, so as to model according to the actual shape, thereby enabling accurate determination of local flow field information in the future.

[0058] Optionally, the second grid size can be determined based on the size of the local area.

[0059] For example, see again Figure 2 Taking the target component 11 as a T-shaped steel as an example, a local region 12 can be determined. A model is then created for this local region 12, generating a local fluid dynamics model 20. This local fluid dynamics model 20 includes multiple second meshes. Figure 2 It can be clearly seen that the size of the second grid is smaller than the size of the first grid corresponding to the overall fluid dynamics model 10.

[0060] S104: Based on the overall flow field information, perform transient multiphase flow simulation processing on the local hydrodynamic model to obtain the local flow field information of the local hydrodynamic model.

[0061] In this step, the local fluid dynamics model can be subjected to transient multiphase flow simulation processing by combining the overall flow field information to obtain the local flow field information of the local fluid dynamics model.

[0062] Optionally, when performing transient multiphase flow simulation on the local hydrodynamic model, methods such as CFD can be used to obtain the local flow field information of the local hydrodynamic model.

[0063] Alternatively, when performing transient multiphase flow simulation on the local fluid dynamics model, a method such as Discrete Element Method (DEM) or CFD-DEM coupling can be used to simulate solid phase motion within the multiphase flow. For example, when the overall fluid dynamics model is used for air-liquid concrete two-phase flow calculation, using DEM or CFD-DEM coupling in the local fluid dynamics model can simulate aggregate motion within the concrete, thereby meeting more application scenarios.

[0064] Alternatively, when a target component of a certain specification is widely used, such as when it is widely used in the same multiphase flow region or in different multiphase flow regions, the local hydrodynamic model can be subjected to transient multiphase flow simulation in a data-driven manner. For example, Dynamic Mode Decomposition (DMD) or Physics-Informed Neural Networks (PINN) can be used.

[0065] In some possible implementations, the step of performing transient multiphase flow simulation processing on the local hydrodynamic model based on the overall flow field information to obtain the local flow field information of the local hydrodynamic model includes: Determine the target boundary of the local fluid dynamics model, wherein the target boundary is the boundary of the local fluid dynamics model that is located inside the global fluid dynamics model; Based on the flow field information corresponding to the target boundary in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined; Based on the flow field information corresponding to the target boundary in the local fluid dynamics model, transient multiphase flow simulation is performed on the local region other than the target boundary to determine the local flow field information.

[0066] In the above steps, the boundaries located inside the global fluid dynamics model can be determined from the various boundaries of the local fluid dynamics model. For example, see also... Figure 3 , Figure 3 This is a schematic diagram illustrating a flow field information transmission as an exemplary embodiment of this application. Figure 3 As shown, the local hydrodynamic model 20 generated by modeling the local region 12 has its target boundary located at position S2 (i.e., Figure 3 (The red boundary in the middle), correspondingly, the target boundary is located at position S1 in the overall fluid dynamics model 10.

[0067] In order to achieve effective fusion of subsequent overall flow field information and local flow field information, the flow field information corresponding to the target boundary in the local fluid dynamics model can be determined based on the flow field information corresponding to the target boundary in the overall fluid dynamics model.

[0068] For the region outside the target boundary in the local region, transient multiphase flow simulation can be performed on the region outside the target boundary in the local fluid dynamics model based on the flow field information corresponding to the target boundary in the local fluid dynamics model. For example, methods such as CFD, DEM, CFD-DEM coupling, DMD, or PINN can be used as needed to determine the local flow field information by combining the flow field information corresponding to the target boundary in the local fluid dynamics model and the flow field information corresponding to the region outside the target boundary in the local fluid dynamics model.

[0069] The local flow field information may include the flow field information of each second grid at each time point within the target time period. The flow field information of a certain second grid at each time point includes, but is not limited to, pressure, velocity, phase volume fraction, etc.

[0070] In this way, for the target boundary of the local hydrodynamic model, the corresponding flow field information is determined based on the overall flow field information, and then transient multiphase flow simulation is performed on other regions to achieve loose coupling transfer of boundary information and local dynamics. This ensures both local and overall computational efficiency and that the local region obtains boundary conditions consistent with the overall flow field information, further consolidating the accuracy of flow field information under multi-scale models.

[0071] In some possible implementations, the overall flow field information includes the flow field information of each first grid at each time point within the target time period; The step of determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information corresponding to the target boundary in the overall fluid dynamics model includes: Based on the flow field information of each first grid at each time point within the target time period, the flow field information of the target boundary at each time point within the target time period is determined in the overall fluid dynamics model. For each time point in the target time period, based on the flow field information of the target boundary at the associated time point in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0072] In the above steps, the flow field information of the target boundary at each time point within the target time period can be determined based on the flow field information of each of the first grids at each time point within the target time period. For each time point within the target time period, the flow field information of the target boundary at the associated time point within the overall fluid dynamics model is determined from the flow field information of the target boundary at each time point within the target time period when it is in the overall fluid dynamics model.

[0073] Here, it can be understood that, since the first grid size is larger than the second grid size, the time step between two adjacent time points in the overall fluid dynamics model within the target time period is greater than the time step between two adjacent time points in the local fluid dynamics model within the target time period. For example, the time step corresponding to the overall fluid dynamics model is 1 second, meaning the overall flow field information includes the flow field information of the first grid at 1 second, 2 seconds, 3 seconds, etc., and the time step corresponding to the local fluid dynamics model is 0.1 seconds, meaning the overall flow field information includes the flow field information of the first grid at 1.1 seconds, 1.2 seconds, 1.3 seconds, etc.

[0074] When determining the flow field information of the target boundary at associated time points within the overall fluid dynamics model, specifically, it is determined whether the flow field information at each time point within the target time period exists. If it exists, the flow field information of the target boundary at that time point within the overall fluid dynamics model is determined as the flow field information of the target boundary at the associated time point within the overall fluid dynamics model. If it does not exist, the flow field information of the target boundary at two time points adjacent to that time point within the target time period within the overall fluid dynamics model is determined as the flow field information of the target boundary at the associated time point within the overall fluid dynamics model.

[0075] For example, for t=1s, the flow field information of the target boundary at each time point within the target time period in the overall fluid dynamics model exists at t=1s. Therefore, the flow field information of the target boundary at t=1s in the overall fluid dynamics model is determined as the flow field information of the target boundary at the associated time point in the overall fluid dynamics model.

[0076] For example, at t=1.1s, the flow field information of the target boundary at each time point within the target time period in the overall fluid dynamics model does not exist at t=1.1s, but the flow field information of the target boundary at each time point within the target time period in the overall fluid dynamics model does exist at t=1s and t=2s. Therefore, the flow field information of the target boundary at t=1s and the flow field information of the target boundary at t=2s in the overall fluid dynamics model can be determined as the flow field information of the target boundary at the associated time point in the overall fluid dynamics model.

[0077] When determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information of the target boundary at the associated time point when it is in the overall fluid dynamics model, specifically, the flow field information of the target boundary at the associated time point when it is in the overall fluid dynamics model can be interpolated to obtain the flow field information corresponding to the target boundary in the local fluid dynamics model.

[0078] Optionally, interpolation can be performed separately in the time and / or spatial dimensions. It can be understood that the time dimension corresponds to each point in time within the target time period, and the spatial dimension corresponds to each first grid and each second grid.

[0079] For cases where the associated time point coincides with the current time point, such as the aforementioned example where the time point is t=1s, since the associated time point coincides with the current time point, no interpolation in the time dimension is required; only interpolation in the spatial dimension is needed. When performing interpolation in the spatial dimension, different interpolation methods can be used according to different accuracy and computational efficiency requirements, such as nearest neighbor interpolation, linear interpolation, and least squares interpolation. This interpolates the flow field information when the target boundary is in the global fluid dynamics model (where the global fluid dynamics model has a large mesh size and sparse data) to the local fluid dynamics model (where the local fluid dynamics model has a small mesh size and dense data).

[0080] For cases where the associated time point is inconsistent with the actual time point, such as the aforementioned example where the time point is t=1.1s, since the associated time point is inconsistent with the actual time point, in order to better adapt to the mesh size and time step of the local fluid dynamics model when the overall flow field information is transferred to the local fluid dynamics model, interpolation processing is performed in both the time and spatial dimensions. When performing interpolation in the time dimension, linear interpolation can be used. For example, the flow field information of the target boundary in the local fluid dynamics model at t=1.1s = 0.9 × the flow field information of the target boundary in the overall fluid dynamics model at t=1s + 0.1 × the flow field information of the target boundary in the overall fluid dynamics model at t=2s. The interpolation processing in the spatial dimension is similar to that in the aforementioned embodiment where the associated time point is consistent with the actual time point; the specific description is the same as in the aforementioned embodiment and will not be repeated here. Different interpolation methods can be used according to different accuracy and computational efficiency requirements, such as nearest neighbor interpolation, linear interpolation, least squares difference, etc.

[0081] In this way, by using the flow field information of the overall model at all time points within the target time period as the boundary data source, the local model boundary is matched and associated with time points one by one, so that the local boundary conditions evolve synchronously with the overall evolution. This avoids phase mismatch caused by the difference between the overall and local time steps, and ensures that the local transient calculation obtains continuous and conserved driving force with the macroscopic flow throughout the entire process. Thus, without increasing the burden on the overall mesh, high-fidelity capture of local fine flow characteristics is achieved, improving the efficiency and accuracy of overall-local coupling.

[0082] In some other possible implementations, the overall flow field information includes the flow field information of each first grid at each time point within the target time period; The step of determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information corresponding to the target boundary in the overall fluid dynamics model includes: Based on the flow field information of each first grid at each time point within the target time period, the flow field information of the local region at each time point within the target time period in the overall fluid dynamics model is determined. For the first time point in the target time period, the preset flow field information is determined as the flow field information corresponding to the target boundary in the local hydrodynamic model; For each non-first time point in the target time period, based on the local flow field information of that time point determined in the previous time step, and the flow field information of the local region in the overall fluid dynamics model at each time point in the target time period, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0083] In the above steps, the flow field information of the local region in the overall fluid dynamics model can be determined based on the flow field information of each first grid at each time point within the target time period.

[0084] For the first time point in the target time period, the preset flow field information is determined as the flow field information corresponding to the target boundary in the local fluid dynamics model. The preset flow field information can be set manually, and its specific value is not limited. It can be understood that the flow field information of the overall fluid dynamics model and the local fluid dynamics model at the first time point in the target time period can be set manually. Specifically, the flow field information of the local fluid dynamics model at the first time point in the target time period can be determined based on the flow field information of the corresponding position of the overall fluid dynamics model at the first time point in the target time period, thereby maintaining consistency with the flow law in actual application.

[0085] For each non-first time point in the target time period, the local flow field information for that time point has already been calculated in the previous time step. For example, for the time point t=1.1s, the step size of the time step corresponding to the local fluid dynamics model is Δt=0.1s. The local flow field information for t=1.1s has been determined in the previous time step from 1s to 1.1s. Therefore, based on the local flow field information for that time point determined in the previous time step, and the flow field information of the local region in the overall fluid dynamics model at each time point in the target time period, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0086] In this way, by utilizing the flow field information of each first grid at each time point within the target time period, time-varying drive is provided for the target boundary. The flow field information corresponding to the first moment in the target time period is used as the preset flow field information to avoid initial disturbances and ensure the stability of the local flow field information. At each subsequent time point, the local flow field information of the next time point determined in the previous time step is combined with the flow field information of the local region at each time point within the target time period in the overall fluid dynamics model. The flow field information of the target boundary corresponding to the local fluid dynamics model is updated progressively, thereby ensuring the temporal consistency of multiphase flow wave characteristics in cross-scale transmission. This enables the local fluid dynamics model and the overall fluid dynamics model to achieve time synchronization, which helps to improve the efficiency of fine feature capture and maintain the overall fast solution advantage.

[0087] In some possible implementations, determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the local flow field information determined at the previous time step and the flow field information of the local region at various time points within the target time period in the overall fluid dynamics model includes: From the flow field information of the local region in the overall fluid dynamics model at each time point, determine the flow field information of the target time point that satisfies the preset conditions as the local flow field information of the time point determined in the previous time step at that time point; Based on the flow field information of the local region in the overall fluid dynamics model at the target time point, the flow field information of the target boundary in the overall fluid dynamics model at the target time point is determined; Based on the flow field information of the target boundary at the target time point in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0088] In the above steps, from the flow field information of the local region in the overall fluid dynamics model at each time point, the flow field information of the target time point that satisfies the preset conditions of the local flow field information at the time point determined in the previous time step is selected. Then, from the flow field information of the local region in the overall fluid dynamics model at the target time point, the flow field information of the target boundary in the overall fluid dynamics model at the target time point is extracted. Thus, based on the flow field information of the target boundary in the overall fluid dynamics model at the target time point, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0089] In this way, using the local flow field information determined at the previous time step as a reference, when the local region is in the global fluid dynamics model, the flow field information at each time point that meets the preset conditions is searched. The flow field information at the target time point when the target boundary is in the global fluid dynamics model is mapped to the corresponding flow field information of the target boundary in the local fluid dynamics model. This achieves accurate matching of the flow field information of the target boundary, helps to eliminate the phase mismatch caused by the difference between the global and local time steps, ensures the continuity of the flow field information, and keeps the local flow field information synchronized with the flow of the global flow field information in the evolution of multiple time points. This effectively improves the stability and accuracy of the determination of flow field information under the multi-scale framework.

[0090] In some possible implementations, the preset conditions include: The target fluid phase has a consistent volume within the local area, or the target fluid phase has a consistent volume distribution at the target boundary.

[0091] Here, the preset condition may be that the volume of the target fluid phase in the local region of the overall fluid dynamics model is consistent with the volume of the target fluid phase in the local region of the local fluid dynamics model; or that the volume distribution of the target fluid phase at the target boundary in the overall fluid dynamics model is consistent with the volume distribution of the target fluid phase at the target boundary in the local fluid dynamics model.

[0092] The target fluid phase is the most important fluid phase in multiphase flow. Taking the two-phase flow of concrete pouring as an example, one phase is air and the other is liquid concrete. In practical applications, users are often more concerned about the flow field of liquid concrete. Therefore, the target fluid phase is liquid concrete.

[0093] Thus, due to the large-scale grid setting of the overall fluid dynamics model, the modeling of the target boundary is simplified, which may cause the flow field in the overall fluid dynamics model to change with time to differ from the actual situation. By using preset conditions related to the target fluid phase volume, time calibration between the overall fluid dynamics model and the local fluid dynamics model can be achieved, which helps to improve the accuracy of the processing results.

[0094] In some possible implementations, the determination of the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information of the target boundary at the target time point in the overall fluid dynamics model includes: Interpolation processing is performed on the flow field information of the target boundary at the target time point in the overall fluid dynamics model to obtain the flow field information of the target boundary in the local fluid dynamics model.

[0095] In the above steps, when the overall flow field information is transmitted to the local fluid dynamics model, interpolation is performed to adapt to the mesh size and time step of the local fluid dynamics model.

[0096] When interpolating the flow field information of the target boundary at the target time point within the overall fluid dynamics model, specifically, interpolation is performed on the flow field information of the target boundary at the target time point in both the time and spatial dimensions. It can be understood that the time dimension corresponds to each time point within the target time period, and the spatial dimension corresponds to each first grid and each second grid.

[0097] Optionally, when interpolating the flow field information of the target boundary at the target time point in the overall fluid dynamics model in the time dimension, linear interpolation can be used. Based on the volume of the target fluid phase in the local area, or the volume distribution of the target fluid phase at the target boundary, determine two other volume values ​​(one slightly larger, one slightly smaller) from the flow field information of the target boundary at various time points within the target time period in the overall fluid dynamics model. These two volume values ​​are closest to the volume of the target fluid phase in the local area or the volume distribution of the target fluid phase at the target boundary at the target time point. Linear interpolation is then performed based on these two determined volume values. When interpolating the flow field information of the target boundary at the target time point in the overall fluid dynamics model in the spatial dimension, different interpolation methods can be used according to different accuracy and computational efficiency requirements, such as nearest neighbor interpolation, linear interpolation, least squares difference, etc.

[0098] In this way, when the overall flow field information is transmitted to the local fluid dynamics model, interpolation is performed to adapt to the grid size and time step of the local fluid dynamics model. This ensures the accurate transmission of flow field information at each time point within the target time period for each first grid. It maintains the dynamic consistency of flow field transmission between the overall fluid dynamics model and the local fluid dynamics model, and avoids false disturbances caused by spatial mismatch when determining the subsequent local flow field information. This helps to enhance the stability and accuracy of flow field information determination under a multi-scale framework.

[0099] In some possible implementations, after determining the flow field information of the local region at various time points within the target time period in the overall fluid dynamics model, the phase volume fraction can be converted to obtain the converted phase volume fraction.

[0100] Specifically, when the phase volume fraction is less than the preset phase volume fraction, the converted phase fraction is determined as a first value; when the phase volume fraction is greater than or equal to the preset phase volume fraction, the converted phase fraction is determined as a second value; the first value is less than the second value.

[0101] For example, taking a preset phase volume fraction of 0.5, a first value of 0, and a second value of 1 as an example, the conversion can be performed using the following formula (1): (1) in, This represents the phase volume fraction before the conversion. This indicates the phase volume fraction after conversion.

[0102] S105: Based on the overall flow field information and the local flow field information, determine the target flow field information of the multiphase flow region.

[0103] In this step, the overall flow field information and the local flow field information are combined to obtain the target flow field information of the multiphase flow region.

[0104] In some possible implementations, determining the target flow field information of the multiphase flow region based on the overall flow field information and the local flow field information includes: The target flow field information of the multiphase flow region is obtained by replacing the flow field information corresponding to the local region in the overall flow field information with the local flow field information.

[0105] In this step, the flow field information corresponding to the local region in the overall flow field information can be removed and the local flow field information can be added to obtain the target flow field information of the multiphase flow region.

[0106] In this way, by directly replacing the flow field information of the corresponding local region in the overall flow field information with local flow field information, the seamless integration of the global flow field information is achieved. While ensuring the overall computational efficiency, by adding the fine flow characteristics of the target local area to the macro flow characteristics, the accuracy discontinuity caused by scale differences is eliminated, ensuring that the target flow field information has both large-scale continuity and retains the accuracy of local details, thus fully presenting the overall and local coupling characteristics of the multiphase flow region.

[0107] The embodiments disclosed herein have good adaptability and scalability. In some possible implementations, three-level or more-level models can be established according to the complexity of the flow field information, and the flow field information at different scales can be determined step by step, thereby improving processing efficiency and accuracy.

[0108] To more clearly illustrate the process of determining the flow field, see [link to relevant documentation]. Figure 4 This is a schematic diagram illustrating a flow field determination process, as shown in an exemplary embodiment of this application. Figure 4 As shown, a multiphase flow region can be modeled based on the overall region parameters and the first grid size to generate an overall hydrodynamic model; transient multiphase flow simulation is performed on the overall hydrodynamic model to obtain the overall flow field information of the overall hydrodynamic model; a local region including the target component is determined from the multiphase flow region, and a local region is modeled based on the local region parameters and the second grid size to generate a local hydrodynamic model; transient multiphase flow simulation is performed on the local hydrodynamic model based on the overall flow field information to obtain the local flow field information of the local hydrodynamic model; and the target flow field information of the multiphase flow region is determined based on the overall flow field information and the local flow field information. Specific steps are described in the foregoing embodiments and will not be repeated here.

[0109] In this way, the overall flow field information of a large multiphase flow region can be determined, as well as the local flow field information of the local region where the target component is located. Then, the target flow field information of the multiphase flow region can be determined comprehensively. In this process, the overall flow field information can be determined separately. The determination of the overall flow field information does not require the information of the local fluid dynamics model. Moreover, there is only one-way data transfer between the overall fluid dynamics model and the local fluid dynamics model. There is no need to determine the flow field information of different models at the same time, avoiding the complex inter-model communication and iteration process, which is easy to implement.

[0110] The flow field determination method provided in this application constructs fluid dynamics models of different scales and ranges. The grid size within each model is adapted to the overall size of the model, thereby controlling the number of grids. First, a larger-sized grid is used to quickly determine the overall flow field information. Then, a smaller-sized grid is used to determine the local flow field information at the target component. By determining the flow field information at different scales step by step, the impact of global fine grid on processing efficiency is avoided, while ensuring high fidelity in local areas. This achieves efficient determination of the overall flow at a large scale and the fine flow in local areas, while meeting the requirements of efficiency and accuracy.

[0111] Those skilled in the art will understand that, in the above-described method of the specific implementation, the order in which each step is written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic.

[0112] Corresponding to the embodiments of the aforementioned flow field determination method, this application also provides embodiments of the flow field determination device.

[0113] Please see Figure 5 This is a schematic diagram of a flow field determination device illustrated in an exemplary embodiment of this application. Figure 5 As shown in the figure, the flow field determination device 500 provided in this application embodiment includes: The first modeling module 501 is used to collect the overall region parameters of the multiphase flow region, and to model the multiphase flow region based on the overall region parameters and the first grid size to generate an overall fluid dynamics model; the overall fluid dynamics model includes multiple first grids; The first processing module 502 is used to perform transient multiphase flow simulation processing on the overall fluid dynamics model to obtain the overall flow field information of the overall fluid dynamics model. The second modeling module 503 is used to determine a local region including the target component from the multiphase flow region, collect local region parameters of the local region, and model the local region based on the local region parameters and the second grid size to generate a local hydrodynamic model; the local hydrodynamic model includes multiple second grids; the size of the second grid is smaller than the size of the first grid. The second processing module 504 is used to perform transient multiphase flow simulation processing on the local hydrodynamic model based on the overall flow field information to obtain the local flow field information of the local hydrodynamic model. The flow field determination module 505 is used to determine the target flow field information of the multiphase flow region based on the overall flow field information and the local flow field information.

[0114] In some possible implementations, the first modeling module 501 is further configured to: During the generation of the overall fluid dynamics model, if the deviation between the size of any component in any dimension and the size of the component in other dimensions is greater than a first preset threshold, the size of the component in that dimension is determined to be 0.

[0115] In some possible implementations, the first modeling module 501 is further configured to: During the generation of the overall fluid dynamics model, if the ratio of the size of any component in any dimension to the size of the first mesh is less than a second preset threshold, and the region where the component is located can be represented by the corresponding target region or the boundary where the component is located can be represented by the corresponding target boundary, the region where the component is located is determined according to the corresponding target region or the boundary where the component is located is determined according to the corresponding target boundary. The target region and the target boundary are used to indicate the addition of a drag term.

[0116] In some possible implementations, the second modeling module 503, when determining a local region including the target component from the multiphase flow region, is specifically used for: Based on the location of the target component in the multiphase flow region and the overall flow field information, a local region including the target component is determined.

[0117] In some possible implementations, when the second modeling module 503 determines a local region including the target component based on the location of the target component in the multiphase flow region and the overall flow field information, it is specifically used for: Based on the overall flow field information, the boundary length of the local region is determined; The local region is determined based on the location of the center point of the target component in the multiphase flow region and the boundary length.

[0118] In some possible implementations, the second processing module 504 is specifically used for: Determine the target boundary of the local fluid dynamics model, wherein the target boundary is the boundary of the local fluid dynamics model that is located inside the global fluid dynamics model; Based on the flow field information corresponding to the target boundary in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined; Based on the flow field information corresponding to the target boundary in the local fluid dynamics model, transient multiphase flow simulation is performed on the local region other than the target boundary to determine the local flow field information.

[0119] In some possible implementations, the overall flow field information includes the flow field information of each first grid at each time point within the target time period; When the second processing module 504 determines the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information corresponding to the target boundary in the overall fluid dynamics model, it is specifically used for: Based on the flow field information of each first grid at each time point within the target time period, the flow field information of the target boundary at each time point within the target time period is determined in the overall fluid dynamics model. For each time point in the target time period, based on the flow field information of the target boundary at the associated time point in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0120] In some possible implementations, the overall flow field information includes the flow field information of each first grid at each time point within the target time period; When the second processing module 504 determines the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information corresponding to the target boundary in the overall fluid dynamics model, it is specifically used for: Based on the flow field information of each first grid at each time point within the target time period, the flow field information of the local region at each time point within the target time period in the overall fluid dynamics model is determined. For the first time point in the target time period, the preset flow field information is determined as 0 for the flow field information corresponding to the target boundary in the local fluid dynamics model; For each non-first time point in the target time period, based on the local flow field information of that time point determined in the previous time step, and the flow field information of the local region in the overall fluid dynamics model at each time point in the target time period, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0121] In some possible implementations, when the second processing module 504 determines the flow field information corresponding to the target boundary in the local fluid dynamics model based on the local flow field information determined at the previous time step and the flow field information of the local region at various time points within the target time period in the overall fluid dynamics model, it is specifically used for: From the flow field information of the local region in the overall fluid dynamics model at each time point, determine the flow field information of the target time point that satisfies the preset conditions as the local flow field information of the time point determined in the previous time step at that time point; Based on the flow field information of the local region in the overall fluid dynamics model at the target time point, the flow field information of the target boundary in the overall fluid dynamics model at the target time point is determined; Based on the flow field information of the target boundary at the target time point in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

[0122] In some possible implementations, the preset conditions include: The target fluid phase has a consistent volume within the local area, or the target fluid phase has a consistent volume distribution at the target boundary.

[0123] In some possible implementations, when the second processing module 504 determines the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information of the target boundary at a target time point in the overall fluid dynamics model, it is specifically used for: Interpolation processing is performed on the flow field information of the target boundary at the target time point in the overall fluid dynamics model to obtain the flow field information of the target boundary in the local fluid dynamics model.

[0124] In some possible implementations, the flow field determination module 505 is specifically used for: The target flow field information of the multiphase flow region is obtained by replacing the flow field information corresponding to the local region in the overall flow field information with the local flow field information.

[0125] The specific implementation process of the functions and roles of each unit in the above device can be found in the implementation process of the corresponding steps in the above method, and will not be repeated here.

[0126] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this application according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0127] Based on the same technical concept, this application also provides a computer device 600, referring to... Figure 6 The diagram shown is a schematic representation of the structure of a computer device according to an exemplary embodiment of this application, comprising: The processor 610, memory 620, and bus 630 are included. The memory 620 is used to store execution instructions and includes main memory 621 and external memory 622. The main memory 621, also known as internal memory, is used to temporarily store the operation data in the processor 610 and the data exchanged with external memory 622 such as hard disk. The processor 610 exchanges data with external memory 622 through main memory 621.

[0128] In this embodiment, the memory 620 is specifically used to store application code that executes the solution of this application, and its execution is controlled by the processor 610. That is, when the electronic device 600 is running, the processor 610 communicates with the memory 620 through the bus 630, or the processor 610 communicates with the memory 620 through other means, so that the processor 610 executes the application code stored in the memory 620, and then executes the steps of the flow field determination method described in any of the foregoing embodiments.

[0129] The memory 620 may be, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.

[0130] Processor 610 may be an integrated circuit chip with signal processing capabilities. The aforementioned processor can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor can be a microprocessor or any conventional processor.

[0131] It is understood that the structures illustrated in the embodiments of this application do not constitute a specific limitation on the electronic device 600. In other embodiments of this application, the electronic device 600 may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0132] This disclosure also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the flow field determination method described in the above-described method embodiments. The storage medium can be a volatile or non-volatile computer-readable storage medium.

[0133] This disclosure also provides a computer program product, which stores a computer program. When the computer program is run by a processor, it executes the steps of the flow field determination method provided in any of the above embodiments of this disclosure. For details, please refer to the above method embodiments, which will not be repeated here.

[0134] The aforementioned computer program product can be implemented through hardware, software, or a combination thereof. In one optional embodiment, the computer program product is specifically embodied in a computer storage medium, which can be a volatile or non-volatile computer-readable storage medium. In another optional embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0135] Furthermore, embodiments of the subject matter and functional operation described in this specification can be implemented in the following ways: digital electronic circuits, tangibly embodied computer software or firmware, computer hardware including the structures disclosed in this specification and their structural equivalents, or combinations thereof. Embodiments of the subject matter described in this specification can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions encoded on a tangible, non-transitory program carrier for execution by a data processing apparatus or for controlling the operation of a data processing apparatus. Alternatively or additionally, program instructions may be encoded on artificially generated propagation signals, such as machine-generated electrical, optical, or electromagnetic signals, which are generated to encode information and transmit it to a suitable receiving device for execution by the data processing apparatus. The computer storage medium may be a machine-readable storage device, a machine-readable storage substrate, a random or serial access memory device, or combinations thereof.

[0136] The processing and logic flow described in this specification can be executed by one or more programmable computers that execute one or more computer programs to perform corresponding functions by operating on input data and generating output. The processing and logic flow can also be executed by dedicated logic circuitry—such as FPGAs (Field-Programmable Gate Arrays) or ASICs (Application-Specific Integrated Circuits), and the device can also be implemented as dedicated logic circuitry.

[0137] Suitable computers for executing computer programs include, for example, general-purpose and / or special-purpose microprocessors, or any other type of central processing unit. Typically, the central processing unit receives instructions and data from read-only memory and / or random access memory. The basic components of a computer include a central processing unit for implementing or executing instructions and one or more memory devices for storing instructions and data. Typically, a computer will also include one or more mass storage devices for storing data, such as disks, magneto-optical disks, or optical disks, or the computer will be operatively coupled to such mass storage devices to receive data from or transfer data to them, or both. However, a computer is not required to have such devices. Furthermore, a computer can be embedded in another device, such as a mobile phone, a personal digital assistant (PDA), a mobile audio or video player, a game console, a global positioning system (GPS) receiver, or a portable storage device such as a universal serial bus (USB) flash drive, to name a few.

[0138] Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, such as semiconductor memory devices (e.g., EPROM, EEPROM, and flash memory devices), magnetic disks (e.g., internal hard disks or removable disks), magneto-optical disks, and CD-ROM and DVD-ROM disks. Processors and memory may be supplemented by or incorporated into dedicated logic circuitry.

[0139] While this specification contains numerous specific implementation details, these should not be construed as limiting the scope of any invention or the scope of the claims, but rather are primarily intended to describe features of specific embodiments of a particular invention. Certain features described in the various embodiments herein may also be implemented in combination in a single embodiment. Conversely, various features described in a single embodiment may also be implemented separately in various embodiments or in any suitable sub-combination. Furthermore, while features may function in certain combinations as described above and even initially claimed in this way, one or more features from a claimed combination may be removed from that combination in some cases, and a claimed combination may refer to a sub-combination or a variation thereof.

[0140] Similarly, although the operations are depicted in a specific order in the accompanying drawings, this should not be construed as requiring these operations to be performed in the specific order shown or sequentially, or requiring all illustrated operations to be performed to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. Furthermore, the separation of various system modules and components in the above embodiments should not be construed as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

[0141] Thus, specific embodiments of the subject matter have been described. Other embodiments are within the scope of the appended claims. In some cases, the actions recited in the claims may be performed in a different order and still achieve the desired result. Furthermore, the processes depicted in the drawings are not necessarily shown in a specific order or sequence to achieve the desired result. In some implementations, multitasking and parallel processing may be advantageous.

[0142] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for determining a flow field, characterized in that, The method includes: Collect overall region parameters of the multiphase flow region, and model the multiphase flow region based on the overall region parameters and the first grid size to generate an overall fluid dynamics model; the overall fluid dynamics model includes multiple first grids; during the generation of the overall fluid dynamics model, if the ratio of the size of any component in any dimension to the size of the first grid is less than a second preset threshold, and the region where the component is located can be represented by a corresponding target region or the boundary where the component is located can be represented by a corresponding target boundary, the region where the component is located is determined according to the corresponding target region or the boundary where the component is located is determined according to the corresponding target boundary, and the target region and the target boundary are used to indicate the addition of a drag term; The overall fluid dynamics model is subjected to transient multiphase flow simulation to obtain the overall flow field information of the overall fluid dynamics model; A local region including the target component is determined from the multiphase flow region, local region parameters are collected, and the local region is modeled based on the local region parameters and a second grid size to generate a local hydrodynamic model; the local hydrodynamic model includes multiple second grids; the size of the second grid is smaller than the size of the first grid. Based on the overall flow field information, transient multiphase flow simulation is performed on the local hydrodynamic model to obtain the local flow field information of the local hydrodynamic model; Based on the overall flow field information and the local flow field information, the target flow field information of the multiphase flow region is determined.

2. The method according to claim 1, characterized in that, The method further includes: During the generation of the overall fluid dynamics model, if the deviation between the size of any component in any dimension and the size of the component in other dimensions is greater than a first preset threshold, the size of the component in that dimension is determined to be 0.

3. The method according to claim 1, characterized in that, Determining the local region including the target component from the multiphase flow region includes: Based on the location of the target component in the multiphase flow region and the overall flow field information, a local region including the target component is determined.

4. The method according to claim 3, characterized in that, The step of determining a local region including the target component based on the location of the target component in the multiphase flow region and the overall flow field information includes: Based on the overall flow field information, the boundary length of the local region is determined; The local region is determined based on the location of the center point of the target component in the multiphase flow region and the boundary length.

5. The method according to claim 1, characterized in that, The transient multiphase flow simulation processing of the local hydrodynamic model based on the overall flow field information to obtain the local flow field information of the local hydrodynamic model includes: Determine the target boundary of the local fluid dynamics model, wherein the target boundary is the boundary of the local fluid dynamics model that is located inside the global fluid dynamics model; Based on the flow field information corresponding to the target boundary in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined; Based on the flow field information corresponding to the target boundary in the local fluid dynamics model, transient multiphase flow simulation is performed on the region other than the target boundary in the local region to determine the local flow field information.

6. The method according to claim 5, characterized in that, The overall flow field information includes the flow field information of each first grid at each time point within the target time period; The step of determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information corresponding to the target boundary in the overall fluid dynamics model includes: Based on the flow field information of each first grid at each time point within the target time period, the flow field information of the target boundary at each time point within the target time period is determined in the overall fluid dynamics model. For each time point in the target time period, based on the flow field information of the target boundary at the associated time point in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

7. The method according to claim 5, characterized in that, The overall flow field information includes the flow field information of each first grid at each time point within the target time period; The step of determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information corresponding to the target boundary in the overall fluid dynamics model includes: Based on the flow field information of each first grid at each time point within the target time period, the flow field information of the local region at each time point within the target time period in the overall fluid dynamics model is determined. For the first time point in the target time period, the preset flow field information is determined as the flow field information corresponding to the target boundary in the local hydrodynamic model; For each non-first time point in the target time period, based on the local flow field information of that time point determined in the previous time step, and the flow field information of the local region in the overall fluid dynamics model at each time point in the target time period, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

8. The method according to claim 7, characterized in that, The determination of the flow field information corresponding to the target boundary in the local fluid dynamics model based on the local flow field information determined at the previous time step and the flow field information of the local region at various time points within the target time period in the overall fluid dynamics model includes: From the flow field information of the local region in the overall fluid dynamics model at each time point, determine the flow field information of the target time point that satisfies the preset conditions as the local flow field information of the time point determined in the previous time step at that time point; Based on the flow field information of the local region in the overall fluid dynamics model at the target time point, the flow field information of the target boundary in the overall fluid dynamics model at the target time point is determined; Based on the flow field information of the target boundary at the target time point in the overall fluid dynamics model, the flow field information corresponding to the target boundary in the local fluid dynamics model is determined.

9. The method according to claim 8, characterized in that, The preset conditions include: The target fluid phase has a consistent volume within the local area, or the target fluid phase has a consistent volume distribution at the target boundary.

10. The method according to claim 8, characterized in that, The step of determining the flow field information corresponding to the target boundary in the local fluid dynamics model based on the flow field information of the target boundary at the target time point in the overall fluid dynamics model includes: Interpolation processing is performed on the flow field information of the target boundary at the target time point in the overall fluid dynamics model to obtain the flow field information of the target boundary in the local fluid dynamics model.

11. The method according to claim 1, characterized in that, The step of determining the target flow field information of the multiphase flow region based on the overall flow field information and the local flow field information includes: The target flow field information of the multiphase flow region is obtained by replacing the flow field information corresponding to the local region in the overall flow field information with the local flow field information.

12. A flow field determination device, characterized in that, The device includes: The first modeling module is used to collect overall region parameters of the multiphase flow region, and model the multiphase flow region based on the overall region parameters and the first grid size to generate an overall fluid dynamics model. The overall fluid dynamics model includes multiple first grids. During the generation of the overall fluid dynamics model, if the ratio of the size of any component in any dimension to the size of the first grid is less than a second preset threshold, and the region where the component is located can be represented by a corresponding target region or the boundary where the component is located can be represented by a corresponding target boundary, the region where the component is located is determined according to the corresponding target region or the boundary where the component is located is determined according to the corresponding target boundary. The target region and the target boundary are used to indicate the addition of a drag term. The first processing module is used to perform transient multiphase flow simulation processing on the overall fluid dynamics model to obtain the overall flow field information of the overall fluid dynamics model; The second modeling module is used to determine a local region including the target component from the multiphase flow region, collect local region parameters of the local region, and model the local region based on the local region parameters and the second grid size to generate a local hydrodynamic model; the local hydrodynamic model includes multiple second grids; the size of the second grid is smaller than the size of the first grid. The second processing module is used to perform transient multiphase flow simulation processing on the local hydrodynamic model based on the overall flow field information to obtain the local flow field information of the local hydrodynamic model. The flow field determination module is used to determine the target flow field information of the multiphase flow region based on the overall flow field information and the local flow field information.

13. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the flow field determination method according to any one of claims 1 to 11.

14. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the flow field determination method according to any one of claims 1 to 11.

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