Spiral Flow Simulation System, Simulation Method and Electronic Device Based on Initial Perturbation

Abstract

The present invention relates to a spiral flow simulation system, a simulation method and an electronic device based on an initial perturbation. By using the computational fluid dynamics method, an internal flow field analysis model of a complex pipeline system is established. Based on the spiral flow simulation analysis technology of boundary perturbation, the flow pattern of the system is calculated, and a quantitative criterion for whether there are multiple solutions in the flow pattern is given. Through an effective simulation method, the present invention accurately calculates the spiral flow pattern, and gives the influencing parameters and ranges that cause the flow pattern to jump, which has important guiding significance for suppressing flow instability. The present invention can be widely applied to the numerical analysis of the phenomenon of multiple solutions in the flow of complex pipeline systems containing multi-pass structures.

Description

Technical Field

[0001] The present invention relates to a spiral flow simulation system, a simulation method and an electronic device based on initial perturbation, and is particularly applicable to the flow field simulation of a complex space pipeline system with a multi-pass structure. Background Art

[0002] The pipeline layout of the liquid launch vehicle power system is complex and the internal medium flow velocity is high. Telemetry data and ground test data both show that for a complex pipeline system with a multi-pass structure, random pressure jump phenomena will occur inside. The mechanism for generating pressure jumps is that the multi-pass structure in the pipeline makes the flow inside the pipe have non-linear flow multi-solution characteristics. Under specific perturbation conditions, spiral flow along the branch pipe will occur, causing a flow pattern jump from symmetric bifurcation flow to spiral flow. Therefore, there is an urgent need for an effective simulation method that can accurately calculate the spiral flow pattern, and give the influencing parameters and ranges for generating the flow pattern jump, which is of great significance for suppressing flow instability. Summary of the Invention

[0003] The object of the present invention is to overcome the above-mentioned defects of the prior art, and provide a spiral flow simulation method based on initial perturbation. By using the computational fluid dynamics method, an internal flow field analysis model of a complex pipeline system is established, and based on the spiral flow simulation analysis technology of boundary perturbation, the flow pattern of the system is calculated, and a quantitative criterion for whether there are multiple solutions in the flow pattern is given.

[0004] Another object of the present invention is to provide a spiral flow simulation system and an electronic device based on initial perturbation.

[0005] The above object of the present invention is mainly achieved by the following technical solutions:

[0006] A spiral flow simulation method based on initial perturbation, comprising:

[0007] Establish a geometric model of the internal fluid channel of the complex pipeline system;

[0008] Perform structured grid division on the internal fluid channels in the geometric model;

[0009] Import the geometric model after structured grid division into the simulation software, and perform model settings and boundary condition settings;

[0010] Solve by using the bifurcation flow pattern algorithm through the simulation software, and set the solution parameters to obtain the internal flow field A of the complex pipeline system;

[0011] Solve by using the spiral flow pattern algorithm through the simulation software, and set the solution parameters to obtain the internal flow field B of the complex pipeline system;

[0012] Compare the flow field A with the flow field B. If the internal streamlines and flow resistance amplitudes in the flow field A are both consistent with those in the flow field B, it is determined that the flow in the complex pipeline system structure is stable; otherwise, it is determined that the flow in the complex pipeline system structure is unstable, that is, there are multiple flow solutions.

[0013] In the above spiral flow simulation method based on initial perturbation, the complex pipeline system includes a complex pipeline with multiple branches, and the established geometric model of the fluid channel only retains the pipelines before and after the multiple branches.

[0014] In the above spiral flow simulation method based on initial perturbation, when performing structured grid division on the internal fluid channel in the geometric model, the grid of the fluid channel wall boundary layer and the multiple branch positions is encrypted.

[0015] In the above spiral flow simulation method based on initial perturbation, the simulation software is the computational fluid dynamics simulation analysis software CFX.

[0016] In the above spiral flow simulation method based on initial perturbation, the model settings include:

[0017] The analysis type adopts steady-state calculation;

[0018] For liquid media, define the density, viscosity and specific heat capacity at constant pressure of the media; for gas media, define them as ideal gases, and set the molecular weight, viscosity and specific heat capacity at constant pressure;

[0019] Set the reference pressure;

[0020] The heat transfer model adopts the isothermal model Isothermal;

[0021] The turbulence model adopts the standard k-ε model or the RNG k-ε model.

[0022] In the above spiral flow simulation method based on initial perturbation, the boundary condition settings include:

[0023] The inlet of the pipeline system adopts the Opening boundary;

[0024] Set the reference pressure as the working pressure of the pipeline system, and set the inlet pressure to 0 MPa;

[0025] The outlets of each branch pipe are set as flow outlet boundaries, and the remaining surfaces are set as wall boundaries.

[0026] In the above spiral flow simulation method based on initial perturbation, the specific method of using the bifurcated flow pattern algorithm to solve and setting the solution parameters to obtain the internal flow field A of the complex pipeline system is as follows:

[0027] (4.1) Set the flow direction of the pipeline opening to the vertical boundary direction, use the first-order upwind for the convection term, and use the high-order accuracy for the turbulence term to solve the convergence initial field of the complex pipeline. If the convergence residual of the convergence initial field is less than or equal to 10 -6 , go to step (4.2); otherwise, adjust the time scale factor and repeat step (4.1) until the convergence residual of the obtained convergence initial field is less than or equal to 10 -6 , then go to step (4.2);

[0028] (4.2) Take the convergence initial field obtained in step (4.1) as the input item, and use the high-order accuracy for the convection term to calculate the convergence flow field of the complex pipeline.

[0029] In the above spiral flow simulation method based on the initial perturbation, the spiral flow pattern algorithm is used for solving, and the solution parameters are set. The specific method for obtaining the internal flow field B of the complex pipeline system is as follows:

[0030] (5.1) Set the pipeline system inlet to use the Opening boundary, and the angle between the inlet flow direction and the normal of the inlet plane is 40 - 55°, and solve the internal flow field of the complex pipeline system;

[0031] (5.2) If no vortex is observed in the multi-pass interior, continue to solve the internal flow field of the complex pipeline. If the convergence residual is less than or equal to 10 -6 , then end; otherwise, adjust the time scale factor and repeat step (5.2) until the convergence residual is less than or equal to 10 -6 , then end;

[0032] (5.3) If a vortex is observed in the multi-pass interior, then switch the flow direction of the pipeline system opening to the boundary normal direction, and continue to solve the internal flow field of the complex pipeline. If the convergence residual is less than or equal to 10 -6 , then end; otherwise, go to step (5.4);

[0033] (5.4) Gradually obtain a convergence flow field with a convergence residual less than or equal to 10 -6 by using the low-order algorithm first and then the high-order algorithm, and the time scale factor from small to large.

[0034] A spiral flow simulation system based on the initial perturbation includes a geometric model construction module, a mesh generation module, a condition setting module, a determination module, and simulation software, where:

[0035] The geometric model construction module establishes the geometric model of the internal fluid channel of the complex pipeline system and outputs it to the mesh generation module;

[0036] The mesh generation module performs structured mesh generation on the internal fluid channel in the geometric model and imports the geometric model after structured mesh generation into the simulation software;

[0037] A condition setting module performs model setting and boundary condition setting and inputs them into a simulation software;

[0038] The simulation software uses a bifurcated flow pattern algorithm to solve, sets the solution parameters, obtains the internal flow field A of the complex pipeline system, and outputs it to the determination module; uses a helical flow pattern algorithm to solve, sets the solution parameters, obtains the internal flow field B of the complex pipeline system, and outputs it to the determination module;

[0039] The determination module compares the flow field A with the flow field B. If the internal streamlines and flow resistance amplitudes in the flow field A are both consistent with those in the flow field B, it is determined that the structure of the complex pipeline system has stable flow; otherwise, it is determined that the structure of the complex pipeline system has unstable flow, that is, there are multiple flow solutions.

[0040] An electronic device includes a memory and a processor:

[0041] The memory is used to store one or more computer instructions;

[0042] The processor is used to execute the one or more computer instructions for:

[0043] Establish a geometric model of the internal fluid channel of the complex pipeline system;

[0044] Perform structured grid division on the internal fluid channel in the geometric model;

[0045] Import the geometric model after structured grid division into the simulation software and perform model setting and boundary condition setting;

[0046] Solve through the simulation software using a bifurcated flow pattern algorithm, set the solution parameters, and obtain the internal flow field A of the complex pipeline system;

[0047] Solve through the simulation software using a helical flow pattern algorithm, set the solution parameters, and obtain the internal flow field B of the complex pipeline system;

[0048] Compare the flow field A with the flow field B. If the internal streamlines and flow resistance amplitudes in the flow field A are both consistent with those in the flow field B, it is determined that the structure of the complex pipeline system has stable flow; otherwise, it is determined that the structure of the complex pipeline system has unstable flow, that is, there are multiple flow solutions.

[0049] The present invention has the following beneficial effects compared with the prior art:

[0050] (1) The present invention uses the computational fluid dynamics method to establish an internal flow field analysis model of the complex pipeline system, and based on the helical flow simulation analysis technology of boundary perturbation, calculates the system flow pattern and gives a quantitative criterion for whether there are multiple flow solutions in the flow pattern;

[0051] (2) The present invention uses an effective simulation method to accurately calculate the helical flow pattern, and gives the influencing parameters and ranges that cause the flow pattern jump, which has important guiding significance for suppressing flow instability.

[0052] (3) The helical flow simulation method based on initial perturbation proposed by the present invention has achieved good results in the mechanism analysis and design improvement of the random pressure jump problem in the carrier rocket delivery system, and can be widely applied to the numerical analysis of the flow multiple solution phenomenon in complex pipeline systems with multi-pass structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 is the flow chart of the helical flow simulation analysis based on initial perturbation of the present invention;

[0054] Figure 2 is the internal flow channel geometric model after simplification of the complex pipeline of the present invention;

[0055] Figure 3 is the structural block division and computational grid of the complex pipeline structure of the present invention, where 3a is the structured block division and 3b is the computational grid;

[0056] Figure 4 is the typical bifurcated flow pattern of the present invention, where 4a is the streamline of the bifurcated flow pattern; 4b is the pressure field of the five-way cross-section;

[0057] Figure 5 is the convergence residual curve of the typical bifurcated flow pattern of the present invention;

[0058] Figure 6 is the initial rotation initial field of the present invention;

[0059] Figure 7 is the typical helical flow convergence residual curve of the present invention;

[0060] Figure 8 is the typical helical flow pattern of the present invention, where 8a is the pressure field of the five-way cross-section; 8b is the streamline of the helical flow pattern. DETAILED DESCRIPTION OF THE INVENTION

[0061] The present invention will be further described in detail below with reference to the drawings and specific embodiments:

[0062] As Figure 1 shown is the flow chart of the helical flow simulation analysis based on initial perturbation of the present invention. The main steps of analyzing the flow multiple solution phenomenon in the complex pipeline system by using the computational fluid dynamics simulation analysis software CFX and the helical flow simulation method based on initial perturbation of the present invention are as follows:

[0063] I. Construction of geometric model

[0064] Establish a geometric model of the internal fluid passage of a complex pipeline system. The complex pipeline system includes a complex pipeline with multiple branches. Structures such as bellows and nozzle connections in the pipeline are not considered, and only the pipelines before and after the multiple branches are retained to establish the geometric model of the internal flow passage of the complex pipeline system, as Figure 2 shown, where the main pipeline is 1; the five-way pipe is 2; the branch pipelines are 3, 4, 5, and 6.

[0065] II. Mesh Generation

[0066] Based on ICEM CFD, a block strategy is adopted to perform structured mesh generation on the internal flow passage of the complex pipeline in the geometric model, and the grids at the wall boundary layer and the multi-branch positions are appropriately refined, as Figure 3 shown in the block division and computational grid of the complex pipeline structure of the present invention, where 3a is the structured block division and 3b is the computational grid.

[0067] III. Import the geometric model after structured mesh generation into the simulation software and perform model settings and boundary condition settings. In an optional embodiment of the present invention, the simulation software is the computational fluid dynamics simulation analysis software CFX.

[0068] 1. The model settings include:

[0069] The analysis type adopts steady-state calculation;

[0070] For liquid media, define the density, viscosity, and specific heat capacity at constant pressure of the media; for gas media, define them as ideal gases and set the molecular weight, viscosity, and specific heat capacity at constant pressure;

[0071] Set the reference pressure;

[0072] The heat transfer model adopts the isothermal model Isothermal;

[0073] The turbulence model adopts the standard k-ε model or the RNG k-ε model.

[0074] 2. The boundary condition settings include:

[0075] The inlet of the pipeline system adopts the Opening boundary;

[0076] Set the reference pressure and set the inlet pressure to 0 MPa;

[0077] The outlets of each branch pipeline are set as flow outlet boundaries,

[0078] The remaining walls are set as wall boundaries.

[0079] IV. Solve using the split-flow flow pattern algorithm through the simulation software CFX and set the solution parameters to obtain the internal flow field A of the complex pipeline system. The specific method includes:

[0080] (4.1) Set the flow direction of the pipeline opening to the vertical boundary direction, that is, the inlet flow direction of the pipeline system is the normal direction of the boundary. The convective term adopts first-order upwind, and the turbulent term adopts high-order accuracy to solve the converged initial field of the complex pipeline. If the convergence residual of the converged initial field is less than or equal to 10 -6 , proceed to step (4.2). Otherwise, adjust the time scale factor and repeat step (4.1) until the convergence residual of the obtained converged initial field is less than or equal to 10 -6 , and proceed to step (4.2);

[0081] (4.2) Take the converged initial field obtained in step (4.1) as the input term, and adopt high-order accuracy for the convective term to calculate the converged flow field of the complex pipeline.

[0082] In an alternative embodiment of the present invention, the high-order accuracy is second-order.

[0083] As Figure 4 shown is the typical bifurcated flow pattern of the present invention, where 4a is the streamline of the bifurcated flow pattern; 4b is the pressure field at the five-way section;

[0084] As Figure 5 shown is the convergence residual curve of the typical bifurcated flow pattern of the present invention. In the figure, label 1 represents the root mean square residual of pressure; label 2 represents the root mean square residual of velocity in the x direction; label 3 represents the root mean square residual of velocity in the y direction; label 4 represents the root mean square residual of velocity in the z direction.

[0085] V. The specific method for solving using the helical flow pattern algorithm and setting the solution parameters to obtain the internal flow field B of the complex pipeline system is as follows:

[0086] (5.1) Set the inlet of the pipeline system to use the Opening boundary, and set the inlet flow direction to 40 - 55° obliquely, that is, the angle between the inlet flow direction and the normal direction of the inlet plane is 40 - 55°, to generate an initial rotating flow field inside the multi-way of the complex pipeline. In an alternative embodiment of the present invention, it is set to 45°. As Figure 6 shown is the initial rotating initial field of the present invention.

[0087] (5.2) If no vortex is observed inside the multi-way, continue to solve the internal flow field of the complex pipeline. If the convergence residual of the flow field is less than or equal to 10 -6 , then end; otherwise, adjust the time scale factor and repeat step (5.2) until the convergence residual of the obtained initial field is less than or equal to 10 -6 , and end;

[0088] (5.3) If a vortex is observed inside the multi-way, then switch the inlet flow direction of the pipeline system to the normal direction of the boundary and continue to solve the flow field of the internal flow of the complex pipeline. If the convergence residual of the flow field is less than or equal to 10 -6, then end; otherwise, proceed to step (5.4);

[0089] (5.4) Gradually obtain a converged residual less than or equal to 10 by using a low-order algorithm first and then a high-order algorithm, and / or in the order of increasing time scale factor. -6 The converged flow field. As Figure 7 shown is the typical spiral flow converged residual curve of the present invention; the branch pipe shows obvious rotational flow, where label 1 represents the root mean square residual of pressure; label 2 represents the root mean square residual of velocity in the x direction; label 3 represents the root mean square residual of velocity in the y direction; label 4 represents the root mean square residual of velocity in the z direction.

[0090] As Figure 8 shown is the typical spiral flow pattern of the present invention, where 8a is the pressure field at the five-way section; 8b is the streamline of the spiral flow pattern.

[0091] VI. Analysis of Simulation Results

[0092] Compare flow field A with flow field B. If the internal streamlines and flow resistance amplitudes in flow field A are the same as those in flow field B, it is determined that the flow in the complex pipeline system structure is stable; otherwise, it is determined that the flow in the complex pipeline system structure is unstable, that is, there are multiple flow solutions.

[0093] The present invention also provides a spiral flow simulation system based on initial perturbation, including a geometric model construction module, a mesh generation module, a condition setting module, a determination module, and simulation software, where:

[0094] The geometric model construction module establishes a geometric model of the internal fluid channel of the complex pipeline system and outputs it to the mesh generation module;

[0095] The mesh generation module performs structured mesh generation on the internal fluid channel in the geometric model and imports the geometric model after structured mesh generation into the simulation software;

[0096] The condition setting module performs model settings and boundary condition settings and inputs them into the simulation software;

[0097] The simulation software uses the bifurcated flow pattern algorithm to solve and sets the solution parameters to obtain the internal flow field A of the complex pipeline system and outputs it to the determination module; uses the spiral flow pattern algorithm to solve and sets the solution parameters to obtain the internal flow field B of the complex pipeline system and outputs it to the determination module;

[0098] The determination module compares the flow field A with the flow field B. If the internal streamlines and flow resistance amplitudes in flow field A are the same as those in flow field B, it is determined that the flow in the complex pipeline system structure is stable; otherwise, it is determined that the flow in the complex pipeline system structure is unstable, that is, there are multiple flow solutions.

[0099] The present invention also provides an electronic device, including a memory and a processor:

[0100] The memory is used for storing one or more computer instructions;

[0101] The processor is used for executing the one or more computer instructions to:

[0102] Establish a geometric model of the internal fluid channel of a complex pipeline system;

[0103] Perform structured grid division on the internal fluid channel in the geometric model;

[0104] Import the geometric model after structured grid division into simulation software, and perform model settings and boundary condition settings;

[0105] Solve by using the bifurcated flow pattern algorithm through the simulation software, and set the solution parameters to obtain the internal flow field A of the complex pipeline system;

[0106] Solve by using the spiral flow pattern algorithm through the simulation software, and set the solution parameters to obtain the internal flow field B of the complex pipeline system;

[0107] Compare the flow field A with the flow field B. If the internal streamlines and flow resistance amplitudes in the flow field A are both consistent with those in the flow field B, it is determined that the structure of the complex pipeline system has stable flow. Otherwise, it is determined that the structure of the complex pipeline system has unstable flow, that is, there are multiple flow solutions.

[0108] As mentioned above, the above is only the best specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

[0109] The content not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

Claims

1. A spiral flow simulation method based on initial perturbation, characterized in that: Including: Constructing a geometric model of the internal fluid channels in a complex pipeline system; Performing structured grid division on the internal fluid channels in the geometric model; Importing the geometric model after structured grid division into simulation software, and performing model settings and boundary condition settings; Solving by using the bifurcated flow pattern algorithm in the simulation software and setting the solution parameters to obtain the internal flow field A of the complex pipeline system; Solving by using the spiral flow pattern algorithm in the simulation software and setting the solution parameters to obtain the internal flow field B of the complex pipeline system; Comparing the flow field A with the flow field B. If the internal streamlines and flow resistance amplitudes in the flow field A are both consistent with those in the flow field B, it is determined that the structure of the complex pipeline system has stable flow. Otherwise, it is determined that the structure of the complex pipeline system has unstable flow, that is, there are multiple flow solutions; The specific method of solving by using the bifurcated flow pattern algorithm and setting the solution parameters to obtain the internal flow field A of the complex pipeline system is as follows: (4.1) Set the flow direction of the pipeline opening to the vertical boundary direction, use first-order upwind for the convection term, and use high-order accuracy for the turbulence term to solve the convergence initial field of the complex pipeline. If the convergence residual of the convergence initial field is less than or equal to 10 -6 , go to step (4.2). Otherwise, adjust the time scale factor and repeat step (4.1) until the convergence residual of the obtained convergence initial field is less than or equal to 10 -6 , go to step (4.2); (4.2) Using the converged initial field obtained in step (4.1) as the input item, adopting high-order accuracy for the convection term, and calculating the converged flow field of the complex pipeline; The specific method of solving by using the spiral flow pattern algorithm and setting the solution parameters to obtain the internal flow field B of the complex pipeline system is as follows: (5.1) Setting the inlet of the pipeline system to use the Opening boundary, with the angle between the inlet flow direction and the normal direction of the inlet plane being 40 - 55°, and solving the internal flow field of the complex pipeline system; (5.2) If no vortex is observed in the multi-pass, continue to solve the internal flow field of the complex pipeline. If the convergence residual is less than or equal to 10 -6 , then end; otherwise, adjust the time scale factor and repeat step (5.2) until the convergence residual is less than or equal to 10 -6 , and end; (5.3) If vortices are observed to occur in the multi-pass interior, switch the opening flow direction of the pipeline system to the boundary normal direction, and continue to solve the internal flow field of the complex pipeline. If the convergence residual is less than or equal to 10 -6 , then end; otherwise, proceed to step (5.4); (5.4) Gradually obtain a convergent residual less than or equal to 10 by first using a low-order algorithm and then a high-order algorithm, with the time scale factor increasing from small to large. -6 convergent flow field.

2. The spiral flow simulation method based on initial perturbation according to claim 1, wherein: The complex pipeline system includes a complex pipeline with multiple connections, and the established geometric model of the fluid channels only retains the pipelines before and after the multiple connections.

3. The spiral flow simulation method based on initial perturbation according to claim 1, characterized in that: When performing structured grid division on the internal fluid channels in the geometric model, the grid of the fluid channel wall boundary layer and the multiple connection positions is encrypted.

4. The spiral flow simulation method based on initial perturbation according to claim 1, wherein: The simulation software is the computational fluid dynamics simulation analysis software CFX.

5. The spiral flow simulation method based on initial perturbation according to claim 1, characterized in that: The model settings include: The analysis type adopts steady-state calculation; For liquid media, defining the density, viscosity, and specific heat capacity at constant pressure of the media; for gas media, defining as an ideal gas and setting the molecular weight, viscosity, and specific heat capacity at constant pressure; Setting the reference pressure; The heat transfer model adopts the Isothermal model; The turbulence model adopts the standard k-ε model or the RNG k-ε model.

6. The method for simulating spiral flow based on initial perturbation according to claim 1, wherein: The boundary condition settings include: The inlet of the pipeline system uses the Opening boundary; Setting the reference pressure to the working pressure of the pipeline system and setting the inlet pressure to 0 MPa; The outlets of each branch pipe are set as flow outlet boundaries, and the remaining surfaces are set as wall boundaries.

7. A spiral flow simulation system based on initial perturbation, characterized in that: Including a geometric model construction module, a grid division module, a condition setting module, a determination module, and simulation software, where: The geometric model construction module constructs a geometric model of the internal fluid channels in the complex pipeline system and outputs it to the grid division module; The grid division module performs structured grid division on the internal fluid channels in the geometric model and imports the geometric model after structured grid division into the simulation software; The condition setting module performs model settings and boundary condition settings and inputs them into the simulation software; The simulation software uses the bifurcated flow pattern algorithm to solve and sets the solution parameters to obtain the internal flow field A of the complex pipeline system, and outputs it to the determination module; it uses the spiral flow pattern algorithm to solve and sets the solution parameters to obtain the internal flow field B of the complex pipeline system, and outputs it to the determination module; The determination module compares the flow field A with the flow field B. If the internal streamlines and flow resistance amplitudes in the flow field A are both consistent with those in the flow field B, it is determined that the structure of the complex pipeline system has stable flow; otherwise, it is determined that the structure of the complex pipeline system has unstable flow, that is, there are multiple flow solutions; The specific method of using the bifurcated flow pattern algorithm to solve and setting the solution parameters to obtain the internal flow field A of the complex pipeline system is as follows: (4.1) Set the flow direction of the pipeline opening to the vertical boundary direction, use first-order upwind for the convection term, and high-order accuracy for the turbulence term to solve the convergence initial field of the complex pipeline. If the convergence residual of the convergence initial field is less than or equal to 10 -6 , proceed to step (4.2). Otherwise, adjust the time scale factor and repeat step (4.1) until the convergence residual of the obtained convergence initial field is less than or equal to 10 -6 , and proceed to step (4.2); (4.2) Use the converged initial field obtained in step (4.1) as the input item, adopt high-order accuracy for the convection term, and calculate the converged flow field of the complex pipeline; The specific method of using the spiral flow pattern algorithm to solve and setting the solution parameters to obtain the internal flow field B of the complex pipeline system is as follows: (5.1) Set the inlet of the pipeline system to use the Opening boundary, and the angle between the inlet flow direction and the normal direction of the inlet plane is 40 - 55°, and solve the internal flow field of the complex pipeline system; (5.2) If no vortex is observed in the multi-pass, continue to solve the internal flow field of the complex pipeline. If the convergence residual is less than or equal to 10 -6 , then end; otherwise, adjust the time scale factor and repeat step (5.2) until the convergence residual is less than or equal to 10 -6 , and end; (5.3) If vortices are observed to occur in the multi-pass interior, switch the opening flow direction of the pipeline system to the boundary normal direction and continue to solve the internal flow field of the complex pipeline. If the convergence residual is less than or equal to 10 -6 , then end; otherwise, proceed to step (5.4); (5.4) Gradually obtain a converged flow field by first using a low-order algorithm and then a high-order algorithm, with the time scale factor increasing from small to large until the convergence residual is less than or equal to 10 -6 converged flow field 8. An electronic device, characterized in that, It includes a memory and a processor: The memory is used to store one or more computer instructions; The processor is used to execute the one or more computer instructions for: Establish a geometric model of the internal fluid channel of the complex pipeline system; Perform structured grid division on the internal fluid channel in the geometric model; Import the geometric model after structured grid division into the simulation software, and perform model settings and boundary condition settings; Use the bifurcated flow pattern algorithm to solve through the simulation software and set the solution parameters to obtain the internal flow field A of the complex pipeline system; Use the spiral flow pattern algorithm to solve through the simulation software and set the solution parameters to obtain the internal flow field B of the complex pipeline system; Compare the flow field A with the flow field B. If the internal streamlines and flow resistance amplitudes in the flow field A are both consistent with those in the flow field B, it is determined that the structure of the complex pipeline system has stable flow; otherwise, it is determined that the structure of the complex pipeline system has unstable flow, that is, there are multiple flow solutions; The specific method of using the bifurcated flow pattern algorithm to solve and setting the solution parameters to obtain the internal flow field A of the complex pipeline system is as follows: (4.1) Set the flow direction of the pipeline opening to the vertical boundary direction, use first-order upwind for the convection term, and high-order accuracy for the turbulence term to solve the convergence initial field of the complex pipeline. If the convergence residual of the convergence initial field is less than or equal to 10 -6 , go to step (4.2). Otherwise, adjust the time scale factor and repeat step (4.1) until the convergence residual of the obtained convergence initial field is less than or equal to 10 -6 , and go to step (4.2); (4.2) Use the converged initial field obtained in step (4.1) as the input item, adopt high-order accuracy for the convection term, and calculate the converged flow field of the complex pipeline; The specific method of using the spiral flow pattern algorithm to solve and setting the solution parameters to obtain the internal flow field B of the complex pipeline system is as follows: (5.1) Set the inlet of the pipeline system to use the Opening boundary, and the angle between the inlet flow direction and the normal direction of the inlet plane is 40 - 55°, and solve the internal flow field of the complex pipeline system; (5.2) If no vortex is observed in the multi-way, continue to solve the internal flow field of the complex pipeline. If the convergence residual is less than or equal to 10 -6 , then end; otherwise, adjust the time scale factor and repeat step (5.2) until the convergence residual is less than or equal to 10 -6 , and end; (5.3) If a vortex is observed to generate in the multi-pass, switch the opening flow direction of the pipeline system to the boundary normal direction, and continue to solve the internal flow field of the complex pipeline. If the convergence residual is less than or equal to 10 -6 , then end; otherwise, proceed to step (5.4); (5.4) Gradually obtain a converged residual less than or equal to 10 by first using a low-order algorithm and then a high-order algorithm, with the time scale factor increasing from small to large. -6 converged flow field.

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