Method and system for simulating behavior of three-phase contact line in local deformation runner

Abstract

The invention belongs to the field of nuclear power reactor safety design in a marine environment, and particularly relates to a method and system for simulating three-phase contact line behaviors in a local deformation runner, and the system comprises a model building module which is used for building a multi-phase flow model coupled with multi-field force; the boundary processing module is used for processing local deformation wall surface and high-flow-speed outlet boundary conditions; and the simulation platform module is used for performing dynamic simulation and post-processing analysis and outputting key physical parameters. By constructing a special simulation platform, dynamic visualization and quantitative analysis of the whole process of formation and expansion of the dry spots in the narrow rectangular flow channel are realized for the first time, and a powerful scientific tool support is provided for revealing the internal mechanism of boiling heat transfer crisis from the mesoscale.

Description

Technical Field

[0001] This invention belongs to the field of nuclear power reactor safety design technology in marine environments, and more specifically, it relates to a method and system for simulating the behavior of three-phase contact lines in a locally deformed flow channel. Background Technology

[0002] In advanced nuclear reactor designs such as those using plate fuel elements, narrow rectangular flow channels are the core areas for coolant flow and heat transfer. Their compact structure and large specific surface area enable extremely high power densities, but also pose serious challenges to heat transfer safety. When local heat loads are too high or flow is unstable, the liquid film on the heated wall may rupture, forming "dry spots," which can lead to heat transfer crises such as "deviation from nucleus boiling" or "drying up," causing a sudden rise in wall temperature and seriously threatening reactor safety.

[0003] Traditional computational fluid dynamics methods often face challenges in dealing with microscopic interface problems such as moving contact lines, including insufficient interface capture accuracy, difficulty in precisely applying contact angle boundary conditions, and high computational complexity. Especially in complex marine environments such as rocking and tilting, the dynamic changes in the direction and magnitude of the gravitational field, coupled with the potential for minute local deformations in fuel assemblies due to thermal stress, further complicate multiphase flow behavior, making it difficult for traditional macroscopic methods to accurately describe such coupling effects.

[0004] The Lattice Boltzmann Method (LBM), as a method for simulating the behavior of three-phase contact lines in locally deformed flow channels and a system mesoscopic numerical method, has inherent advantages in handling complex boundary and multiphase flow interface evolution. However, existing LBM multiphase flow models still have significant shortcomings when applied to the complex operating conditions of nuclear power reactors: the physical model does not fully couple variable gravity and wall wettability; the boundary conditions have poor stability under high Reynolds numbers and irregular walls; and there is a lack of a dedicated platform for dynamic visualization and quantitative analysis of speckle evolution.

[0005] Therefore, in view of this, we study and improve the existing structure and its shortcomings, and provide a method and system for simulating the behavior of three-phase contact lines in a locally deformed flow channel, in order to achieve a more practical purpose. Summary of the Invention

[0006] In view of the problems mentioned in the background art above, the present invention provides a method and system for simulating the behavior of three-phase contact lines in a locally deformed flow channel.

[0007] In a first aspect, the technical solution adopted by the present invention is as follows: A method for simulating the behavior of a three-phase contact line in a locally deformed flow channel, comprising the following steps: S1: Constructing a multiphase flow model coupled with multiple forces, using the multi-relaxation time lattice Boltzmann method as the basic framework, introducing a pseudo-potential model to describe the interphase interaction forces, and coupling the gravitational field and solid-liquid adhesion force as external force terms; S2: Processing the locally deformed wall surface, using a boundary scheme based on non-equilibrium extrapolation; S3: Processing the high-velocity outlet, using velocity boundary conditions with a stabilization factor; S4: Based on the multiphase flow model described in S1, the boundary scheme described in S2, and the boundary conditions described in S3, performing dynamic simulation, automatically tracking the position of the three-phase contact line, identifying the dry spot region; and calculating at least one physical parameter among the liquid film thickness, dynamic contact angle, dry spot area, and local evaporation flux.

[0008] Furthermore, the steps in S1 for constructing the multiphase flow physical model include: S11: using a pseudo-potential model to describe the separation and interaction between fluid phases; S12: simulating the equivalent gravity field changes caused by the marine environment by introducing a time-varying acceleration vector; S13: controlling the static contact angle of the wall by applying an adjustable adhesion force to the fluid nodes near the wall.

[0009] Furthermore, the pseudopotential in the pseudopotential model of S11 is a function of fluid density, and its specific form is determined by the nonideal gas equation of state.

[0010] Furthermore, the step of identifying dry spots in S4 includes: setting a density threshold for the gas and liquid phases; if the fluid density of a node near the wall is lower than the threshold, then the node is determined to be covered by the gas phase and marked as a dry spot node; the area formed by all dry spot nodes is the dry spot.

[0011] Furthermore, the step of calculating the dynamic contact angle in S4 includes: determining the tangent slope of the gas-liquid interface at the three-phase contact line, and obtaining the dynamic contact angle by calculating the angle between the tangent and the wall surface.

[0012] Furthermore, the step of calculating the local evaporation flux in S4 includes: after coupling the phase change model, integrating the mass source term representing the local evaporation or condensation rate within the interface transition region.

[0013] Secondly, the technical solution adopted by the present invention is as follows: a system for simulating the behavior of three-phase contact lines in a locally deformed flow channel, including a model building module for establishing a multiphase flow model coupled with multiple forces; a boundary processing module for processing the boundary conditions of locally deformed walls and high-velocity outlets; and a simulation platform module for dynamic simulation and post-processing analysis, outputting key physical parameters.

[0014] Furthermore, the simulation platform module supports two-dimensional or three-dimensional computational domain initialization and automatically identifies dry spot nodes and three-phase contact lines.

[0015] Furthermore, it also includes a visualization module for dynamically displaying the evolution of dry spots, contact line movement, and distribution of physical parameters.

[0016] Thirdly, the present invention also discloses a computer-readable storage medium having a computer program stored thereon, the computer program being used to cause a computer to perform the above-described method.

[0017] The beneficial effects of this invention are:

[0018] 1. By establishing a more complete multi-field force coupling physical model, the physical fidelity and accuracy of the simulation results are significantly improved, enabling it to more realistically reflect the complex multiphase flow behavior within the narrow rectangular flow channel of a nuclear power reactor.

[0019] 2. The proposed improved boundary condition handling scheme effectively enhances the stability of numerical calculations, broadens the applicability of the model, and enables it to reliably handle extreme conditions such as high Reynolds number flows and local wall deformation.

[0020] 3. By constructing a dedicated simulation platform, this invention has for the first time achieved dynamic visualization and quantitative analysis of the entire process of dry spot formation and expansion in narrow rectangular channels, providing a powerful scientific tool to support the revelation of the intrinsic mechanism of boiling heat transfer crisis at the mesoscale.

[0021] 4. The high-precision simulation capabilities and quantitative output parameters provided by this invention have significant engineering application value. They can be directly used to verify and improve macroscopic heat transfer and safety analysis models in engineering design, thereby providing solid technical support for improving the design reliability and operational safety of narrow rectangular flow channel components in nuclear power reactors. Attached Figure Description

[0022] The present invention can be further illustrated by the non-limiting embodiments given in the accompanying drawings;

[0023] Figure 1 This is a two-dimensional cloud map showing the thickness distribution of the liquid film on the heated wall surface in Embodiment 1 of the present invention.

[0024] Figure 2 This is a schematic diagram of the variation curve of the average radial movement speed of the three-phase contact line over time in Embodiment 2 of the present invention;

[0025] Figure 3 This is a schematic diagram illustrating the evolution of the dry spot area and its growth rate over time in Embodiment 3 of the present invention.

[0026] Figure 4 This is a schematic diagram of the dynamic contact angle of the dry spot edge over time in Embodiment 4 of the present invention.

[0027] Figure 5 This is a two-dimensional cloud map of the local evaporation flux distribution on the heated wall surface in Embodiment 5 of the present invention;

[0028] Figure 6 This is a schematic diagram of the computer system of the electronic device of the present invention. Detailed Implementation

[0029] A method for simulating the behavior of a three-phase contact line in a locally deformed flow channel includes the following steps:

[0030] S1: Construct a multiphase flow model with coupled multi-field forces, using the multi-relaxation time lattice Boltzmann method as the basic framework, introducing a pseudo-potential model to describe the interphase interaction forces, and coupling the gravitational field and solid-liquid adhesion force as external force terms.

[0031] The evolution equations for this multiphase flow model are as follows:

[0032]

[0033] The collision operator uses the MRT collision matrix M. -1 S replaces the traditional single relaxation time (BGK) operator. By applying independent relaxation rates to different physical quantities in the moment space, the MRT model can significantly improve its numerical stability at high Reynolds numbers. The model uses the Shan-Chen pseudopotential model to describe the interphase forces F of the non-ideal fluid. int This force achieves phase separation by introducing a "pseudo-potential" φ(ρ), which is a function of the fluid density ρ, and its form is determined according to the equation of state (EOS, such as Carnahan-Starling):

[0034]

[0035] Where G is a constant controlling the intensity of the interphase interaction, and ωi is a weighting coefficient. Finally, through multi-force field coupling, the changing gravitational field F is... g and solid-liquid adhesion F s Integrating as an external force term into the LBM evolution equation, a solid-liquid adhesion force Fs is applied to the fluid nodes near the wall to simulate a specific contact angle:

[0036]

[0037] Among them G ads It is the adhesion strength parameter that controls the wettability of the wall surface, and S(x) is the indicator function, which is adjusted by G. ads The relative magnitude of G and the static contact angle can be controlled. Subsequently, a volume force F is introduced. g To simulate the equivalent gravitational field changes caused by marine environments (such as swaying and tilting):

[0038]

[0039] Where g(t) is the acceleration vector that changes with time, g(t)=[gx(t), gy(t), gz(t)], which reflects the change in the reactor core attitude.

[0040] Regarding boundary condition handling, this invention proposes a composite boundary handling scheme—namely S2 and S3—to address the potential local minor deformations of narrow rectangular channel walls and high-velocity outlet problems.

[0041] S2: For locally deformable walls, a boundary scheme based on non-equilibrium extrapolation is used.

[0042] For deformable walls, a stepped approximation is used as the basic scheme, simply dividing the computational mesh nodes into solid nodes or fluid nodes. For fluid particles, a standard bounce scheme is adopted.

[0043]

[0044] To accurately handle locally deformed surfaces that are not aligned with the mesh, a non-equilibrium rebound scheme is employed. This is achieved by reconstructing the unknown distribution function from the wall at the boundary fluid nodes. The core idea is to separate and extrapolate the non-equilibrium portion, replacing complex geometric interpolation. At t+δ t At time x, fluid node f The distribution function at point f is i (x f, t+δ t The distribution function after the collision can be decomposed into:

[0045]

[0046] Where f i neq It is the non-equilibrium part, ρ f and u f It is x f Macroscopic quantities at the location.

[0047] S3: For high-velocity outlets, velocity boundary conditions with stabilization factors are used.

[0048] For the export side, by introducing a stabilization factor related to the local Reynolds number and combining it with a non-equilibrium extrapolation scheme based on upstream information, numerical oscillations are effectively suppressed, ensuring computational stability and physical consistency under complex geometry and high flow velocity conditions. The core improvement lies in the reconstruction of the non-equilibrium state, extrapolating from the upstream node xin: .

[0049] S4: Based on the multiphase flow model described in S1, the boundary scheme described in S2, and the boundary conditions described in S3, perform dynamic simulation, automatically track the position of the three-phase contact line, identify the dry spot region, and calculate at least one physical parameter among the liquid film thickness, dynamic contact angle, dry spot area, and local evaporation flux.

[0050] Based on the above model and boundary conditions, this invention constructs an integrated simulation platform that supports the entire process from initial condition setting to dynamic simulation and post-processing analysis. Initial condition setting includes establishing a two-dimensional or three-dimensional computational domain representing a narrow rectangular flow channel, setting the initial liquid film thickness and contact angle, and loading the initial flow field. During the simulation, the system can track the position of the gas-liquid-solid three-phase contact line on the flow channel wall in real time and automatically identify the formation and expansion of dry spots. The system defines a density threshold ρ. th As the criterion for judging gas and liquid phases, we take: If x f instantaneous density ρ(x) at point f , t) < ρ th If the wall node is covered by the gas phase, it is determined that the node is a dry spot node. After the dry spot forms, the area composed of all the dry spot nodes is the dry spot, and the system automatically identifies this area from the wetted area (ρ>ρ). th The boundary line on the wall is defined as the three-phase contact line (TCL).

[0051] During or after the simulation, the system automatically post-processes the stored transient data, calculates and outputs key physical parameters. For the liquid film thickness h(x, y, t), linear interpolation is performed at the grid nodes to find the density ρ. th The location of the gas-liquid interface, where the liquid film thickness is defined as the distance from the interface to the wall:

[0052]

[0053] Dynamic contact angle θ d (t) By calculating the slope mint of the tangent at the gas-liquid interface at the three-phase contact line (TCL) using the system, the dynamic contact angle is the angle between this tangent and the wall surface:

[0054]

[0055] The area of ​​the dry speckle is determined by the number of marked dry speckle nodes N. d (t), multiplied by the area of ​​a single grid A cell The total dry spot area A(t) is obtained. Finally, after coupling the phase transition model, the LBM continuity equation includes a mass source term S. pc (x,t) represents the local evaporation or condensation rate, and the local evaporation flux. By analyzing the source phase Spc Integrating over the entire interface transition area yields:

[0056] .

[0057] Specifically, within the entire system:

[0058] For the geometric modeling of locally deformable walls, the system defines and generates the geometry of the flow channel wall with local deformation in a parametric manner. First, it checks whether the lateral range of the deformation region has been defined in the input parameters. If not, it automatically calculates the range based on the preset deformation center position and deformation radius, and constrains it within the effective grid index of the computational domain.

[0059] The wall profile construction process is as follows: The system initializes the entire lower wall as a horizontal baseline by default. Based on the user-specified deformation type, the wall shape is modified within a preset deformation area. For parabolic deformation, the system calculates the normalized distance of each grid point within the area relative to the deformation center and generates convex or concave profiles according to the parabolic equation, the amplitude of which is controlled by the deformation amplitude parameter. Finally, the calculated deformation profiles are superimposed on the baseline to generate wall geometry with smooth local deformation. If the user selects the 'flat' type or specifies an unknown type, the system maintains a flat baseline for the wall. This method allows the system to flexibly simulate minute wall deformations caused by mechanical stress, vibration, etc., without complex mesh reconstruction.

[0060] Secondly, through a series of computational steps, including the calculation of pseudopotential and interphase forces, the calculation of solid-liquid adhesion forces, the application of volume forces, the updating of the velocity field and the summarization of the resultant forces, and the application of outlet boundary conditions, the system realizes the coupling of various forces and the application of key boundary conditions in the pseudopotential multiphase flow model.

[0061] Calculation of pseudopotential and interphase forces:

[0062] The system first calculates the pseudopotential value at each grid node using the equation of state based on the density and pressure distribution of the current flow field. Then, through a cyclic shift operation, the system obtains the pseudopotential values ​​of adjacent nodes in each grid direction. Based on this, the interphase interaction force is calculated according to the core formula of the pseudopotential model; this force drives the separation of the gas and liquid phases and the formation of the interface. In the calculation, the contribution of solid obstacle nodes is excluded.

[0063] Solid-liquid adhesion calculation:

[0064] To simulate wall wettability, the system introduces solid-liquid adhesion. This force is achieved by detecting whether the neighbors of each fluid node in each grid direction are solid walls. The magnitude of the adhesion force is proportional to the wall wettability parameter and the wall pseudopotential, and its direction is towards or away from the wall, thus enabling precise control of the static contact angle.

[0065] Application of volume force:

[0066] The system simulates external force fields, such as varying gravitational fields, by introducing volume forces. This force is related to the difference between local density and reference density and can be used to simulate the effect of changes in equivalent gravitational acceleration on flow under complex conditions such as ocean swaying and tilting.

[0067] Velocity field update and resultant force summary:

[0068] All calculated forces—interphase forces, adhesion forces, and volume forces—are vectorized to obtain the total external force. Subsequently, based on the theory of the lattice Boltzmann method, the system updates the macroscopic velocity field using the current velocity distribution function and the total external force.

[0069] Export boundary conditions:

[0070] For the outlet boundary, the system implements an improved Zou-He scheme. This processing addresses the bottom and top outlet boundaries of the computational domain by using specific combinations of distribution functions to determine the unknown distribution function. This approach, incorporating upstream information, effectively suppresses numerical oscillations under high flow velocity conditions, ensuring physical consistency and numerical stability in the outlet boundary processing.

[0071] Furthermore, for the calculation of lattice Boltzmann evolution, the core solver of the system performs evolution calculations based on a multi-relaxation time model. The simulation at each time step includes two main steps: a migration step and a collision step.

[0072] In the migration step, the particle distribution function at each grid node migrates along its corresponding discrete velocity direction to neighboring grid nodes, simulating the convective motion of particles. In the collision step, the system first calculates the equilibrium distribution function based on the macroscopic physical quantities of the current flow field, namely density and velocity. Then, the current distribution function is transformed from velocity space to moment space. In moment space, the system applies independent relaxation rates to moments with different physical meanings, defined by a diagonal matrix A, to relax them towards equilibrium. The choice of relaxation rate is related to the fluid phase; for example, different relaxation times are used for liquid and gas phases, which significantly improves the numerical stability of the model when handling flows with high density ratios and high Reynolds numbers. Finally, the relaxed moments are transformed back to velocity space using an inverse transformation matrix to obtain the post-collision distribution function, thus completing the evolution of one time step.

[0073] Finally, during or after the simulation, the system automatically post-processes the transient data, extracting and calculating a series of key physical parameters, including the gas-liquid interface position and liquid film thickness, dynamic contact angle, and dry spot area.

[0074] Gas-liquid interface location and liquid film thickness

[0075] The system scans upwards from the wall at each lateral position along the flow direction, searching for grid nodes where the fluid density first falls below the gas-liquid phase determination threshold. The location of this node is recorded as the gas-liquid interface height at that point. The liquid film thickness is defined as the vertical distance from this interface height to the wall.

[0076] Dynamic contact angle

[0077] The system selects a representative local window near the identified three-phase contact line. Linear fitting is performed on the interface height data within this window to obtain the local tangent slope of the gas-liquid interface at that location. The dynamic contact angle is obtained by calculating the angle between this tangent and the horizontal wall surface, and is output in degrees.

[0078] Dry spot area identification and calculation

[0079] Within a specific height band near the wall, the system marks all grid nodes with a density below a threshold; these nodes constitute the dry spot region. The total area of ​​the dry spots is obtained by counting the number of these marked nodes and multiplying it by the area of ​​a single grid cell. Simultaneously, the system also calculates the fraction of the dry spot area relative to the total wall area within that height band to quantify the extent of dry spot expansion.

[0080] Example 1:

[0081] Figure 1 The image shows a two-dimensional cloud map of the liquid film thickness distribution on the heated wall surface at time step t = 5000 (grid unit).

[0082] The simulation results clearly capture the nucleation and expansion process of the dry spot. The dark blue area in the figure represents the core region of the dry spot with a liquid film thickness h≈0, which is completely occupied by the gas phase. A distinct transition region, the contact line region, exists at the edge of the dry spot, where the liquid film thickness rapidly increases from 0 to the main liquid film thickness h. The system accurately outputs the liquid film thickness h(x,y) at different locations, verifying the robustness of the model in handling large deformations at the gas-liquid interface.

[0083] Example 2:

[0084] Figure 2 This demonstrates the average radial movement velocity v of the three-phase contact wire (TCL). cl Curve showing how it changes over time.

[0085] In the early stages of dry spot formation, when t < 1000, the contact linear velocity rises rapidly due to local surface tension imbalance, exhibiting a rapid dewetting process. Subsequently, in the stage where t > 2000, limited by viscous dissipation and contact angle hysteresis, the contact linear velocity gradually tends to a quasi-steady-state fluctuation value, approximately 0.015 lu / ts. This velocity fluctuation reflects the pinning-slip physical mechanism of the micro-interface moving between mesh nodes as captured by the LBM model.

[0086] Example 3:

[0087] Figure 3 The evolution of the dry spot area A(t) and its growth rate dA / dt over time is shown.

[0088] The curves show a non-linear, accelerating growth trend in the dry spot area. Initially, the growth rate is relatively slow; however, as the contact line expands, the contact perimeter between the gas-liquid interface and the heated wall increases, leading to intensified evaporation and consequently driving the dry spot area growth rate dA / dt to rise approximately linearly. This quantitative data is consistent with classical boiling heat transfer experimental patterns, demonstrating the potential of this platform in predicting deviations from nucleation boiling time.

[0089] Example 4:

[0090] Figure 4 This demonstrates the dynamic contact angle θ at the edge of the dry spot, i.e., the three-phase contact line. d Curve showing how it changes over time.

[0091] In the initial stage, the liquid film begins to recede upon heating, and the dynamic contact angle decreases rapidly. As the contact line continues to retreat, this contact angle, after reaching a certain critical value (approximately 60° around 1000 time steps), tends to a relatively stable dynamic retreat contact angle, fluctuating within a small range. This fluctuation reflects the discontinuous motion characteristics of the contact line at the microscopic level, consistent with the actually observed contact angle hysteresis phenomenon, verifying the model's accurate handling of solid-liquid adhesion.

[0092] Example 5:

[0093] Figure 5 The diagram shows a two-dimensional distribution contour map of the local evaporation flux m′ on the heated wall surface at time step t=5000 during the stable expansion phase of the dry spot.

[0094] Simulation results clearly show that in the core region of the dry spot, the liquid film has completely evaporated, and the evaporation flux approaches zero. However, at the edge of the dry spot, near the three-phase contact line, the local evaporation flux reaches its peak due to the extremely thin liquid film and high interface temperature. This peak region is the main heat transfer area, and its distribution shape is closely related to the dry spot profile. This verifies that the system can accurately capture the local characteristics of phase change heat transfer, providing crucial microscopic data for optimizing heat transfer design and predicting deviations from nucleation boiling.

[0095] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a computer's processor, causes the computer to perform the rule engine configuration method for early warning as described above. This computer-readable storage medium may be included in the electronic device described in the above embodiments, or it may exist independently and not assembled into the electronic device.

[0096] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, system, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, system, or device. Computer programs contained on computer-readable media can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0097] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0098] The units described in the embodiments of this application can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0099] The present invention has been described in detail above. The specific embodiments are provided only to help understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for simulating the behavior of three-phase contact lines in a locally deformed flow channel, characterized in that: Includes the following steps: S1: Construct a multiphase flow model with coupled multi-field forces, using the multi-relaxation time lattice Boltzmann method as the basic framework, introducing a pseudo-potential model to describe the interphase interaction forces, and coupling the gravitational field and solid-liquid adhesion force as external force terms. S2: For locally deformable walls, a boundary scheme based on non-equilibrium extrapolation is used. S3: For high-velocity outlets, velocity boundary conditions with stabilization factors are used. S4: Based on the multiphase flow model described in S1, the boundary scheme described in S2, and the boundary conditions described in S3, perform dynamic simulation, automatically track the position of the three-phase contact line, identify the dry spot region, and calculate at least one physical parameter among the liquid film thickness, dynamic contact angle, dry spot area, and local evaporation flux.

2. The method for simulating the behavior of three-phase contact lines in a locally deformed flow channel according to claim 1, characterized in that: The steps for constructing the multiphase flow physical model in S1 include: S11: A pseudo-potential model is used to describe the separation and interaction between fluid phases; S12: The equivalent gravitational field changes caused by the marine environment are simulated by introducing a time-varying acceleration vector; S13: Control of the static contact angle of the wall surface is achieved by applying adjustable adhesion at the fluid nodes near the wall surface.

3. The method for simulating the behavior of three-phase contact lines in a locally deformed flow channel according to claim 2, characterized in that: The pseudopotential in the pseudopotential model of S11 is a function of fluid density, and its specific form is determined by the nonideal gas equation of state.

4. The method for simulating the behavior of three-phase contact lines in a locally deformed flow channel according to claim 1, characterized in that: The step of identifying dry spots in S4 includes: setting a density threshold for the gas and liquid phases; if the fluid density of a node near the wall is lower than the threshold, then the node is determined to be covered by the gas phase and marked as a dry spot node; the area formed by all dry spot nodes is the dry spot.

5. The method for simulating the behavior of three-phase contact lines in a locally deformed flow channel according to claim 1, characterized in that: The step of calculating the dynamic contact angle in S4 includes: determining the tangent slope of the gas-liquid interface at the three-phase contact line, and obtaining the dynamic contact angle by calculating the angle between the tangent and the wall surface.

6. The method for simulating the behavior of three-phase contact lines in a locally deformed flow channel according to claim 1, characterized in that: The step of calculating the local evaporation flux in S4 includes: after coupling the phase change model, integrating the mass source term representing the local evaporation or condensation rate in the interface transition region.

7. A system for simulating the behavior of a three-phase contact line in a locally deformed flow channel, characterized in that: include The model building module is used to build multiphase flow models coupled with multiple forces. The boundary processing module is used to handle locally deformable walls and high-velocity outlet boundary conditions; The simulation platform module is used for dynamic simulation and post-processing analysis, and outputs key physical parameters.

8. The system for simulating the behavior of three-phase contact lines in a locally deformed flow channel according to claim 7, characterized in that: The simulation platform module supports two-dimensional or three-dimensional computational domain initialization and automatically identifies dry spot nodes and three-phase contact lines.

9. The system for simulating the behavior of three-phase contact lines in a locally deformed flow channel according to claim 7, characterized in that: It also includes a visualization module for dynamically displaying the evolution of dry spots, contact line movement, and distribution of physical parameters.

10. A computer-readable storage medium, characterized in that: It contains a computer program that causes the computer to perform the method of any one of claims 1-6.

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