A numerical simulation method, device and equipment

Abstract

The present application relates to the field of numerical simulation technology, and discloses a numerical simulation method, device and equipment. The method includes: establishing a numerical simulation model, including a flow field simulation model and a reaction simulation model; based on the reaction dynamic initial conditions, performing full coupling solution on the first physical field equations corresponding to the flow field simulation model and the second physical field equations corresponding to the reaction simulation model to obtain a flow field updated simulation result; when the flow field updated simulation result meets the flow field stability condition, separately solving the second physical field equations based on the flow field updated simulation result to obtain a flow field stable simulation result; when the flow field stable simulation result meets the flow field update condition, using the flow field stable simulation result as the reaction dynamic initial condition, and repeating the steps of full coupling solution and separate solution until the target reaction process ends. The beneficial effect is that it reduces the coupling degree of multiple physical fields, reduces the complexity of the solution process, and improves the efficiency and accuracy of numerical simulation.

Description

Technical Field

[0001] This application relates to the field of numerical simulation technology, and in particular, to a numerical simulation method, device, and equipment. Background Art

[0002] In many fields, there are various reaction processes for synthesizing target products, and some of the reaction processes involve complex reaction systems, including multiphase reactions or parallel reactions, etc. For example, the reaction process for synthesizing cyclic carbonates has a gas-liquid-solid three-phase coupling characteristic in its reaction system, which increases the complexity of heat and mass transfer during the reaction process. Similar reaction systems usually involve complex thermodynamic and kinetic characteristics during the reaction process, making it difficult to accurately predict and control the reaction process. Therefore, in order to effectively monitor and optimize the reaction process, it is usually necessary to analyze the complex reaction system by means of numerical simulation. In the related art, the complexity of the numerical simulation method still needs to be improved. Summary of the Invention

[0003] This application provides a numerical simulation method, device, and equipment, which respectively perform full coupling solution and separate solution on the physical field equations included in the numerical simulation model according to the flow field stability condition in the target reaction process, reduce the coupling degree between multiple physical fields in the numerical simulation model, and improve the efficiency and accuracy of numerical simulation.

[0004] To achieve the above object, the main technical solutions adopted in this application include:

[0005] In a first aspect, an embodiment of this application provides a numerical simulation method, and the method includes:

[0006] Establish a numerical simulation model; wherein, the numerical simulation model is used to perform numerical simulation on the target reaction process for synthesizing the target product, the numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model corresponds to initial reaction dynamic conditions;

[0007] Based on the initial reaction dynamic conditions, perform full coupling solution on the first physical field equations corresponding to the flow field simulation model and the second physical field equations corresponding to the reaction simulation model to obtain a flow field updated simulation result;

[0008] When the flow field updated simulation result satisfies the flow field stability condition, perform separate solution on the second physical field equations based on the flow field updated simulation result to obtain a flow field stable simulation result;

[0009] When the steady-state flow field simulation results meet the flow field update conditions, use the steady-state flow field simulation results as the initial reaction dynamic conditions, and repeat the steps of fully coupling the solution of the first physical field equations and the second physical field equations, and separately solving the second physical field equations until the target reaction process ends.

[0010] The numerical simulation method proposed in the embodiments of the present application fully couples the flow field simulation model and the reaction simulation model when the target reaction process is in the unsteady flow field stage, so as to obtain the updated flow field simulation results while updating the flow field characteristics; when the target reaction process is in the steady flow field stage, freeze the flow field simulation model and separately solve the reaction simulation model to obtain the steady flow field simulation results. Compared with the solution scheme of directly coupling all physical field models in the related art, the present application dynamically adapts the coupling of the physical field models included in the numerical simulation model according to the steady flow field situation in the target reaction process, reduces the coupling degree between multiple physical fields, thereby effectively reducing the computational complexity when solving the physical field equations, and significantly improving the efficiency and accuracy of the numerical simulation.

[0011] Optionally, the fully coupling the solution of the first physical field equations corresponding to the flow field simulation model and the second physical field equations corresponding to the reaction simulation model to obtain the updated flow field simulation results includes:

[0012] Simultaneously establish the first physical field equations and the second physical field equations to obtain the updated flow field equations;

[0013] Use the first time step to fully couple the solution of the updated flow field equations to obtain the updated flow field simulation results;

[0014] Input the updated flow field simulation results as the initial conditions into the updated flow field equations, and repeat the process of fully coupling the solution of the updated flow field equations until the updated flow field simulation results meet the flow field stability conditions.

[0015] Optionally, the separately solving the second physical field equations based on the updated flow field simulation results to obtain the steady flow field simulation results includes:

[0016] Use the second time step to separately solve the second physical field equations to obtain the steady flow field simulation results; where the second time step is longer than the first time step;

[0017] Input the steady flow field simulation results as the initial conditions into the second physical field equations, and repeat the process of separately solving the second physical field equations until the steady flow field simulation results meet the flow field update conditions.

[0018] Optionally, at least one target gas is involved in the target reaction process. The target gas has a gas-liquid dissolution concentration in the slurry phase, and the gas-liquid dissolution concentration is a scalar. The method further includes:

[0019] Calculating a difference between the gas-liquid dissolution concentration and the saturated dissolution concentration of the target gas in the slurry phase to obtain a dissolution concentration difference;

[0020] Calculating a mass transfer flux based on the volumetric mass transfer coefficient and the dissolution concentration difference to obtain a mass transfer flux of the target gas and the slurry phase;

[0021] Numerically representing the mass transfer between the target gas and the slurry phase based on the mass transfer flux and the slurry phase density to obtain a gas-liquid mass transfer source term; wherein, the gas-liquid mass transfer source term represents the mass difference caused by gas-liquid mass transfer in the target reaction process.

[0022] Optionally, the flow field simulation model includes a multiphase flow model. The physical field equations corresponding to the multiphase flow model include continuity equations for each phase. The continuity equations for each phase include a slurry phase continuity equation and a gas phase continuity equation. The continuity equations for each phase are obtained in the following manner:

[0023] Deriving a continuity equation based on the slurry phase mass field data, the slurry phase velocity field data, and the slurry phase mass transfer source term to establish the slurry phase continuity equation; wherein, the slurry phase mass transfer source term is zero;

[0024] Deriving a continuity equation for the gas phase based on the gas phase mass field data, the gas phase velocity field data, and the gas-liquid mass transfer source term to establish the gas phase continuity equation;

[0025] Obtaining the continuity equations for each phase based on the slurry phase continuity equation and the gas phase continuity equation.

[0026] Optionally, the flow field simulation model includes a multiphase flow model. The physical field equations corresponding to the multiphase flow model further include momentum balance equations for each phase. The momentum balance equations for each phase include a slurry phase momentum balance equation and a gas phase momentum balance equation. The momentum balance equations for each phase are obtained in the following manner:

[0027] Deriving a dynamic balance equation based on the slurry phase velocity field data, the relative flow momentum transfer data of the slurry phase, the interfacial force data between the slurry phase and the gas phase, and the slurry phase mass transfer momentum source term to establish the slurry phase momentum balance equation; wherein, the slurry phase mass transfer momentum source term is zero;

[0028] The dynamic balance equation is derived based on the gas phase velocity field data, the gas phase relative momentum transfer data, the gas phase-slurry phase interaction force data and the gas phase mass transfer momentum source term, and the gas phase momentum balance equation is established; wherein the gas phase mass transfer momentum source term is obtained by momentum calculation based on the gas-liquid mass transfer source term; and the momentum balance equations of each phase are obtained based on the slurry phase momentum balance equation and the gas phase momentum balance equation.

[0029] Optionally, at least one target gas participates in the target reaction process, and the target gas has a corresponding gas-liquid dissolved concentration in the slurry phase, and the gas-liquid dissolved concentration is a scalar; the reaction simulation model includes a gas-liquid mass transfer model, and the physical field equation corresponding to the gas-liquid mass transfer model includes a scalar transport equation; the scalar transport equation is obtained by the following method:

[0030] Performing gas-liquid mass transfer calculation according to the gas-liquid dissolved concentration and the saturated dissolved concentration of the target gas in the slurry phase to obtain a gas-liquid mass transfer source term of the target gas;

[0031] Based on the gas-liquid dissolved concentration and the concentration of the reaction components other than the target gas, the mass change caused by the target reaction process is calculated to obtain the chemical reaction source term of the target gas;

[0032] The gas-liquid mass transfer source term, the chemical reaction source term and the concentration field data of the target gas in the slurry phase are subjected to gas-liquid mass transfer equilibrium to obtain the scalar transport equation.

[0033] Optionally, the chemical reaction source term is obtained by:

[0034] Calculating the reaction rate according to the gas-liquid solution concentration of the target gas and the concentration of the reaction components in the target reaction process to obtain a target reaction rate;

[0035] The mass change of the target gas during the target reaction is calculated according to the slurry phase density, the relative molecular mass of the reaction components and the target reaction rate to obtain the chemical reaction source term.

[0036] In a second aspect, an embodiment of the present application provides a numerical simulation device, the device comprising:

[0037] A simulation model building module is used to build a numerical simulation model; wherein the numerical simulation model is used to numerically simulate the target reaction process of synthesizing the target product, the numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model corresponds to the reaction dynamic initial conditions;

[0038] A flow field update simulation module, configured to perform a full coupling solution on a first physical field equation set corresponding to the flow field simulation model and a second physical field equation set corresponding to the reaction simulation model based on reaction dynamic initial conditions, so as to obtain a flow field update simulation result;

[0039] A flow field stability simulation module, configured to, when the flow field update simulation result meets the flow field stability condition, perform a separate solution on the second physical field equation set based on the flow field update simulation result, so as to obtain a flow field stability simulation result;

[0040] An iterative simulation reaction module, configured to, when the flow field stability simulation result meets the flow field update condition, use the flow field stability simulation result as reaction dynamic initial conditions, and repeatedly execute the steps of performing a full coupling solution on the first physical field equation set and the second physical field equation set, and performing a separate solution on the second physical field equation set until the target reaction process ends.

[0041] In a third aspect, an embodiment of the present application provides a computer device, including: a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to execute the method according to any one of the above embodiments.

[0042] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, on which computer instructions are stored, and the computer instructions are used to cause a computer to execute the method according to any one of the above embodiments.

[0043] In a fifth aspect, an embodiment of the present application provides a computer program product, including computer instructions, and the computer instructions are used to cause a computer to execute the method according to any one of the above embodiments. Description of the Drawings

[0044] In order to more clearly illustrate the specific implementation manners of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required to be used in the description of the specific implementation manners or the prior art. Obviously, the following drawings are some implementation manners of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0045] Figure 1 It is a step diagram of the numerical simulation method provided by the embodiment of the present application;

[0046] Figure 2a It is a three-dimensional geometric structure diagram of the stirring reactor model in the embodiment of the present application;

[0047] Figure 2bSchematic diagram of mesh generation for the stirred reactor model in the embodiments of the present application;

[0048] Figure 3 Step diagram for fully coupled solution of the first physical field equations and the second physical field equations in the embodiments of the present application;

[0049] Figure 4 Step diagram for independent solution of the second physical field equations in the embodiments of the present application;

[0050] Figure 5a Gas phase distribution cloud map in the stirred reactor when the simulation result of flow field update meets the flow field stability condition in the embodiments of the present application;

[0051] Figure 5b Volume mass transfer coefficient distribution cloud map in the stirred reactor when the simulation result of flow field update meets the flow field stability condition in the embodiments of the present application;

[0052] Figure 6 Schematic diagram of the curve of the molar fraction of cyclic carbonate varying with reaction time in the embodiments of the present application;

[0053] Figure 7 Step diagram for obtaining the gas-liquid mass transfer source term in the embodiments of the present application;

[0054] Figure 8 Step diagram for obtaining the continuity equations of each phase in the embodiments of the present application;

[0055] Figure 9 Step diagram for obtaining the momentum balance equations of each phase in the embodiments of the present application;

[0056] Figure 10 Step diagram for obtaining the scalar transport equation in the embodiments of the present application;

[0057] Figure 11 Step diagram for obtaining the chemical reaction source term in the embodiments of the present application;

[0058] Figure 12 Module diagram of the numerical simulation device provided in the embodiments of the present application;

[0059] Figure 13 Structural schematic diagram of a computer device provided in the embodiments of the present application. Detailed implementation manners

[0060] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of this application without creative efforts shall fall within the scope of protection of this application.

[0061] In many fields, there are multiple reaction processes for synthesizing target products, and some of the reaction processes involve complex reaction systems, including multiphase reactions or parallel reactions, etc. The complex reaction systems reduce the controllability of the reaction process and increase the difficulty of optimizing the parameters of the reaction process.

[0062] Exemplarily illustrate a reaction system containing complex reactions: Cyclic carbonate is a cyclic compound with an O-CO-O structure in its molecular structure, which is widely used in multiple fields such as battery electrolytes, biomaterials, and organic solvents, and is an important functional material and chemical intermediate. The reaction process for synthesizing cyclic carbonate can include: uniformly dispersing catalyst powder in a liquid phase to form a slurry phase, and dissolving carbon dioxide gas in the slurry phase, so that the carbon dioxide gas dissolved in the liquid phase reacts with liquid epoxide under the action of the catalyst to synthesize cyclic carbonate. In the above reaction process, the reaction system exhibits the characteristics of gas-liquid-solid three-phase coupling, increasing the complexity of heat and mass transfer in the reaction process, and reducing the controllability and safety of the reaction process.

[0063] Similar reaction systems usually involve complex thermodynamic and kinetic characteristics during the reaction process, making it difficult to accurately predict and control the reaction process. Therefore, in order to effectively monitor and optimize the reaction process, it is necessary to analyze the complex reaction system by means of numerical simulation. Traditional process methods usually use small-scale devices for repeated experiments, and adjust the parameters of the reaction process during the repeated experiments to optimize the reaction process. However, the above methods have problems such as long experimental cycles and difficulty in obtaining parameters, and the optimization cost consumed is relatively high, making it impossible to be promoted on a large scale.

[0064] In other related technologies, parameters of the reaction process are also optimized through Computational Fluid Dynamics (CFD). In this method, since the full coupling solution of multiple physical fields involved in the reaction process is carried out, the solution process is greatly affected by the non-linear interaction between physical fields, resulting in problems such as numerical oscillation, difficult convergence, and even calculation collapse. In addition, the reaction process actually used to synthesize the target product may last for a long time, while most CFD models focus on the flow field analysis at the second-level time scale, and the analysis process consumes a large amount of computing resources, resulting in the inability of the CFD model to support the numerical simulation of the long-term reaction process, and thus unable to provide theoretical support for the parameter optimization of the reaction process.

[0065] Based on the above problems, the present application proposes a numerical simulation method, device and equipment. The method includes: establishing a numerical simulation model, including a flow field simulation model and a reaction simulation model; based on the reaction dynamic initial conditions, performing a full coupling solution on the first physical field equations corresponding to the flow field simulation model and the second physical field equations corresponding to the reaction simulation model to obtain a flow field updated simulation result; when the flow field updated simulation result meets the flow field stability condition, separately solving the second physical field equations based on the flow field updated simulation result to obtain a flow field stable simulation result; when the flow field stable simulation result meets the flow field update condition, using the flow field stable simulation result as the reaction dynamic initial condition, and repeating the steps of full coupling solution and separate solution until the target reaction process ends.

[0066] In the numerical simulation method proposed by the present application, when the target reaction process is in the flow field unstable stage, a full coupling solution is performed on the flow field simulation model and the reaction simulation model to obtain a flow field updated simulation result while updating the flow field characteristics; when the target reaction process is in the flow field stable stage, the flow field simulation model is frozen and the reaction simulation model is separately solved to obtain a flow field stable simulation result.

[0067] Compared with the solution scheme of directly coupling all physical field models in the related technology, the present application dynamically adaptively couples the physical field models included in the numerical simulation model according to the flow field stability situation in the target reaction process, reduces the coupling degree between multiple physical fields, thereby effectively reducing the computational complexity when solving the physical field equations, and significantly improving the efficiency and accuracy of numerical simulation.

[0068] The numerical simulation method provided in this specification can be applied to numerically simulate the reaction process involving a complex reaction system, such as the reaction process for synthesizing cyclic carbonates. It can be understood that after appropriate modifications, the numerical simulation method provided in this specification can also be applied to numerically simulate the reaction processes for synthesizing various target products, including but not limited to reaction processes involving multiphase reactions, parallel reactions, and complex heat and mass transfer processes.

[0069] According to an embodiment of the present application, an embodiment of a numerical simulation method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. And although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0070] Refer to Figure 1 As shown, a numerical simulation method is provided in this embodiment. The method includes:

[0071] S100. Establish a numerical simulation model; wherein, the numerical simulation model is used to numerically simulate the target reaction process for synthesizing the target product. The numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model corresponds to initial reaction dynamic conditions.

[0072] S200. Based on the initial reaction dynamic conditions, perform a fully coupled solution to the first physical field equations corresponding to the flow field simulation model and the second physical field equations corresponding to the reaction simulation model to obtain a flow field update simulation result.

[0073] S300. When the flow field update simulation result meets the flow field stability condition, perform a separate solution to the second physical field equations based on the flow field update simulation result to obtain a flow field stability simulation result.

[0074] S400. When the flow field stability simulation result meets the flow field update condition, use the flow field stability simulation result as the initial reaction dynamic condition, and repeat the steps of performing a fully coupled solution to the first physical field equations and the second physical field equations, and performing a separate solution to the second physical field equations until the target reaction process ends.

[0075] Among them, the numerical simulation model can be established based on the target reaction process for synthesizing the target product, including a three-dimensional structure model, a multiphase system model, a multi-physical field model, etc. Among them, the three-dimensional structure model can be obtained by performing three-dimensional modeling based on the physical structure parameters of the reactor structure for the target reaction process, and is used to represent the influence of the reactor structure on the target reaction process. The multiphase system model can be obtained by setting physical property parameters according to the components participating in the reaction during the target reaction process, and is used to describe the target reaction process based on the physical property parameters of each component. The multi-physical field model includes the physical fields involved in the target reaction process, including a flow field simulation model, a reaction simulation model, etc., and is used to comprehensively consider multiple physical phenomena involved in the target reaction process and their interactions.

[0076] The flow field simulation model can be a physical field model used to simulate the changes in flow field characteristics during the target reaction process, including a multiphase flow model, a population balance model, etc. The multiphase flow model includes the continuity equations and momentum balance equations for each phase. The population balance model includes a bubble coalescence model and a bubble breakup model, etc. The population balance model is solved using the discrete method, including breakup kernels and coalescence kernel functions. Exemplarily, the breakup kernel and coalescence kernel functions can use the Luo model, and the bubble diameter discrete range is from 0.5 mm to 10 mm.

[0077] The reaction simulation model can be a physical field model used to simulate the reaction characteristics of each component participating in the reaction process during the target reaction process, including a gas-liquid mass transfer model, a finite rate reaction model, a heat transfer model coupled with reaction enthalpy change, etc. Among them, the gas-liquid mass transfer model can be used to represent the mass transfer between the gas phase and the liquid phase in the reaction system. The finite rate reaction model can be used to represent the reaction rate limitation of the target reaction process. The heat transfer model coupled with reaction enthalpy change can be used to represent the mutual influence between the reaction enthalpy change and the heat transfer process during the target reaction process.

[0078] The initial reaction dynamic conditions can be the initial state of the reaction system obtained based on models such as the three-dimensional structure model, the multiphase system model, and the multi-physical field model before solving the physical field equations, and can include component parameters, heat distribution, physical properties, etc. in the reaction system, and can be used as initial conditions for solving the physical field equations. It can be understood that when repeating the steps of full-coupling solution, the initial reaction dynamic conditions are updated according to the stable simulation results of the flow field to ensure the continuity of the numerical simulation results and make the numerical simulation model closer to the actual target reaction process, improving the accuracy of the numerical simulation results.

[0079] The simulation result of the updated flow field can be the simulation result of the target reaction process under the condition that the flow field characteristics change in real time, including the flow field characteristics and reaction characteristics of the target reaction process, etc., so as to represent the dynamic evolution of the target reaction process in the unstable stage of the flow field. It can be understood that in the fully coupled solution process, the flow field characteristics and reaction characteristics of the target reaction process change simultaneously.

[0080] The flow field stability condition can be determined according to the flow field characteristics of the target reaction process, and is used to judge that the flow field in the corresponding reaction system no longer changes greatly and tends to be stable. Exemplarily, the flow field stability condition can be that the gas holdup volatility of the liquid phase in the reaction system is less than the fluctuation threshold, and its form is as follows:

[0081]

[0082] Wherein, is the gas holdup at the first moment; is the gas holdup at the second moment, is the first time step, ; is the fluctuation threshold. Exemplarily, the fluctuation threshold can be 3%.

[0083] The simulation result of the stable flow field can be the simulation result of the target reaction process under the condition that the flow field characteristics do not change, including the reaction characteristics of the target reaction process, etc., so as to represent the dynamic evolution of the target reaction process in the stable stage of the flow field. It can be understood that in the separate solution process, the reaction characteristics of the target reaction process change, while the flow field characteristics do not change.

[0084] The flow field update condition can be determined according to the reaction characteristics of the target reaction process, including component parameters, etc., indicating that as the target reaction process proceeds, the flow field of the corresponding reaction system gradually moves away from the stable state. Exemplarily, the flow field update condition can be that the mass fraction of the target product in the liquid phase of the corresponding reaction system reaches the mass threshold, such as 10%, 20% or 30%, etc.

[0085] Specifically, three-dimensional modeling is carried out according to the physical structure parameters of the reactor structure for the target reaction process to obtain a three-dimensional reactor model. Exemplarily, for the reaction process of synthesizing cyclic carbonate, it occurs in a stirred reactor. Therefore, a three-dimensional geometric model is established according to the physical structure parameters of the stirred reactor. In this embodiment, the stirred reactor selects a concentric coaxial stirring structure form, the inner impeller selects a six-straight-blade disc turbine impeller, the outer impeller adopts a frame impeller, and an annular gas distributor is arranged below the inner impeller. Three-dimensional modeling is carried out on the above-mentioned stirred reactor to obtain a stirred reactor model as shown in Figure 2a shown. The stirred reactor model is divided into hexahedron meshes to obtain as shown in Figure 2bThe shown mesh generation results are used to combine with the physical structure of the stirred reactor to improve the simulation accuracy of the target reaction process. It should be noted that in the mesh generation results, the near-wall region of the heat exchange wall surface in the stirred reactor is processed with boundary layer mesh refinement to improve the simulation accuracy of the corresponding region. Exemplarily, in the mesh generation results, the orthogonality quality of the divided meshes is higher than 0.3, the skewness is lower than 0.7, and the number of meshes meets the mesh independence requirement.

[0086] Furthermore, physical property parameters are set according to the components participating in the reaction in the target reaction process to obtain a multiphase system model. Based on the location where the target reaction process occurs, the multiphase system model can include the physical property parameters of pure component reactants, slurry mixtures, gas mixtures, or other reactants. Exemplarily, for the reaction process of synthesizing cyclic carbonates, the pure component reactants include carbon dioxide, epoxides, and cyclic carbonates, and their corresponding physical property parameters include viscosity, density, thermal conductivity, specific heat at constant pressure, standard molar enthalpy of formation, and standard molar entropy. The slurry mixture can be a homogeneous mixture of catalyst particles, epoxides, and cyclic carbonates, and its corresponding physical property parameters include density, viscosity, thermal conductivity, and specific heat at constant pressure.

[0087] It should be noted that the physical property parameters of the slurry mixture can be obtained by calculating using the mass-weighted mixing rule, including: based on the mass fractions of the pure component reactants in the slurry mixture, their physical property parameters are weighted and averaged. Among them, the density can be calculated using the mass-weighted harmonic average, the viscosity can be calculated using the mass-weighted geometric average, and both the thermal conductivity and the specific heat at constant pressure can be calculated using the mass-weighted linear average.

[0088] The density and viscosity of the slurry mixture are also corrected based on the solid holdup of the slurry phase to improve the accuracy of the numerical simulation results. The form of the correction formula for density is as follows:

[0089]

[0090] Among them, is the corrected density; is the solid holdup of the slurry phase; is the density of the catalyst. The form of the correction formula for viscosity is as follows:

[0091]

[0092] Among them, is the corrected viscosity; is the liquid-phase viscosity.

[0093] Furthermore, multi-physical field coupling modeling is carried out according to the physical fields involved in the target reaction process to obtain a multi-physical field model, which comprehensively considers multiple physical phenomena involved in the target reaction process and their interactions. After constructing the three-dimensional structure model, multi-phase system model, and multi-physical field model, boundary conditions are set for the above models. The process of setting boundary conditions may include: setting the inlet of the gas distributor in the stirred reactor as a velocity inlet and the outlet as an exhaust surface; using the Multiple Reference Frame (MRF) method to handle the rotation of the agitator paddle in the stirred reactor; setting a standard wall function for the wall of the stirred reactor and setting the corresponding convective heat transfer coefficient; initializing the volume fraction and temperature field of each phase in the multi-phase system model. Exemplarily, the gas flow rate can be set to 7.36 m / s, the rotation speed of the inner paddle moving area in the stirred reactor is 300 rpm, the rotation speed of the outer paddle moving area is 10 rpm, and the rotation directions of the inner and outer paddles are the same.

[0094] Specifically, according to the flow field stability in the target reaction process, dynamic adaptive coupling is performed on the physical field models included in the numerical simulation model to obtain corresponding simulation results through coupled solution. Exemplarily, during the solution process, the PRESTO! format is selected for pressure discretization, the first-order upwind format is used for momentum, the second-order upwind format is used for energy discretization, custom scalar discretization, and each group of component discretizations, and the phase coupled simple algorithm is used for pressure-velocity coupling, and the convergence residual is set to 0.0001.

[0095] Furthermore, when the target reaction process is in the unstable stage of the flow field, full-coupled solution is performed on the first physical field equations corresponding to the flow field simulation model and the second physical field equations corresponding to the reaction simulation model to simulate the dynamic evolution of the target reaction process while updating the flow field characteristics, and a flow field updated simulation result is obtained.

[0096] It can be understood that the flow field updated simulation result includes flow field characteristics. According to the flow field characteristics in the flow field updated simulation result, it can be judged whether the flow field in the reaction system is stable, that is, whether the flow field updated simulation result meets the flow field stability conditions. When the flow field updated simulation result meets the flow field stability conditions, it indicates that the flow field no longer changes significantly and tends to be stable, and the target reaction process enters the stable stage of the flow field.

[0097] Further, when the target reaction process is in the flow field stable stage, freeze the flow field simulation model to keep the flow field characteristics unchanged, and separately solve the second physical field equations corresponding to the reaction simulation model according to the updated simulation results of the flow field to obtain the flow field stable simulation results. Similarly, the flow field stable simulation results also include the flow field characteristics. According to the flow field characteristics in the flow field stable simulation results, it can be judged whether the flow field in the reaction system is stable, that is, whether the flow field stable simulation results meet the flow field update conditions. When the flow field stable simulation results meet the flow field update conditions, it indicates that as the target reaction process progresses, the flow field of the corresponding reaction system gradually moves away from the stable state. Therefore, it is necessary to update the flow field characteristics to fit the actual situation of the target reaction process.

[0098] Further, when the flow field stable simulation results meet the flow field update conditions, use the flow field stable simulation results as the initial reaction dynamic conditions and input them into the first physical field equations and the second physical field equations to perform full coupling solution of the first physical field equations and the second physical field equations according to the flow field stable simulation results, so as to update the flow field characteristics of the corresponding reaction system. It can be understood that in this application, the physical field model is dynamically adaptively coupled according to the flow field stability situation, and the corresponding simulation results are obtained through coupling solution until the target reaction process ends. If the flow field of the corresponding reaction system is in an unstable state when the target reaction process ends, use the flow field update simulation results at this time as the final simulation results; if the flow field of the corresponding reaction system is in a stable state when the target reaction process ends, use the flow field stable simulation results at this time as the final simulation results.

[0099] The numerical simulation method provided in this embodiment performs full coupling solution of the flow field simulation model and the reaction simulation model when the target reaction process is in the flow field unstable stage to obtain the flow field update simulation results while updating the flow field characteristics; when the target reaction process is in the flow field stable stage, freeze the flow field simulation model and perform separate solution of the reaction simulation model to obtain the flow field stable simulation results.

[0100] Compared with the solution scheme of directly coupling all physical field models in the related technology, in this application, according to the flow field stability situation in the target reaction process, the physical field models included in the numerical simulation model are dynamically adaptively coupled, reducing the coupling degree between multiple physical fields, thereby effectively reducing the computational complexity when solving the physical field equations and significantly improving the efficiency and accuracy of numerical simulation.

[0101] Refer to Figure 3 As shown, as an embodiment of this application, performing full coupling solution of the first physical field equations corresponding to the flow field simulation model and the second physical field equations corresponding to the reaction simulation model to obtain the flow field update simulation results, including:

[0102] S210. Combine the first physical field equation group and the second physical field equation group to obtain the flow field update equation group.

[0103] S220. Use the first time step to perform a fully coupled solution on the flow field update equation group to obtain a flow field update simulation result.

[0104] S230. Input the flow field update simulation results as initial conditions into the flow field update equation group, and repeat the process of fully coupling and solving the flow field update equation group until the flow field update simulation results meet the flow field stability condition.

[0105] Specifically, the first set of physical field equations includes the physical field equations corresponding to the multiphase flow model and the group equilibrium model, and the second set of physical field equations includes the physical field equations corresponding to the gas-liquid mass transfer model, the finite rate reaction model, and the heat transfer model coupled with the reaction enthalpy change. The above physical field models are fully coupled to obtain the flow-mass transfer-heat transfer-reaction fully coupled equations, i.e., the flow field update equations, and the equations are solved to obtain the flow field update simulation results.

[0106] Exemplarily, the first time step may be any time step between 0.0005 seconds and 0.005 seconds. The selection of the first time step in an actual scenario may be related to the specific form of the target reaction process or the physical field equation.

[0107] Furthermore, when the flow field update simulation result does not meet the flow field stability condition, it means that the flow field in the corresponding reaction system is still changing significantly, and the flow field update simulation result at this time is input as the initial condition into the flow field update equation group, so as to continue the full coupling solution process according to the flow field update simulation result, until the flow field update simulation result meets the flow field stability condition. It can be understood that the flow field update simulation result is input as the initial condition into the flow field update equation group, and the process of fully coupling solution of the flow field update equation group is repeatedly performed, which ensures the continuity of the simulation results, thereby being closer to the actual target reaction process and improving the accuracy of the numerical simulation results.

[0108] Reference Figure 4 As shown, as an embodiment of the present application, the second physical field equations are solved separately based on the flow field update simulation results to obtain the flow field stability simulation results, including:

[0109] S310. Use a second time step to separately solve the second set of physical field equations to obtain a stable flow field simulation result; wherein the second time step is longer than the first time step.

[0110] S320. Input the flow field stability simulation result as the initial condition into the second physical field equation group, and repeat the process of solving the second physical field equation group separately until the flow field stability simulation result meets the flow field update condition.

[0111] Specifically, when the simulation result of the flow field update satisfies the flow field stability condition, it indicates that the flow field in the corresponding reaction system no longer changes significantly and tends to be stable. Therefore, when solving the physical field equations, the simulation results obtained from the first physical field equation set corresponding to the flow field simulation model can be ignored, and only the second physical field equation set corresponding to the reaction simulation model needs to be solved separately to obtain the flow field stability simulation result, thereby reducing the coupling degree between physical fields, reducing the complexity of solving the physical field equations, and improving the efficiency and accuracy of numerical simulation.

[0112] Exemplarily, the second time step can be selected as any time step between 0.05 seconds and 2 seconds. In the actual scenario, the selection of the second time step can be related to the target reaction process or the specific form of the physical field equation.

[0113] Further, when the flow field stability simulation result does not satisfy the flow field update condition, the flow field in the corresponding reaction system is still in a stable state. Therefore, the second physical field equation set corresponding to the reaction simulation model can still be solved separately. It can be understood that at this time, the flow field stability simulation result is used as the initial condition and input into the second physical field equation set, and the process of separately solving the second physical field equation set is repeated, reducing the computing resources consumed by the coupled flow field simulation model and effectively improving the efficiency of solving the second physical field equation set.

[0114] Exemplarily illustrate the characteristics of the reaction system in this embodiment: Taking the reaction process of synthesizing cyclic carbonate as an example, the time taken for the simulation result of the flow field update to initially satisfy the flow field stability condition in this embodiment is 7.14 seconds. Refer to Figure 5a As shown, when the simulation result of the flow field update initially satisfies the flow field stability condition, the gas phase distribution cloud diagram of the flow field can be obtained according to the flow field stability simulation result. Different colors in the figure represent the high and low gas holdup. Refer to Figure 5b As shown, when the simulation result of the flow field update initially satisfies the flow field stability condition, the volume mass transfer coefficient distribution cloud diagram of the flow field can be obtained according to the flow field stability simulation result. Different colors in the figure represent the size of the volume mass transfer coefficient. Based on Figure 5a and Figure 5b it can be seen that a relatively high gas holdup appears around the agitator paddle of the stirred reactor, that is, the rotation of the agitator paddle causes the gas phase to gather at the agitator paddle, increasing the volume mass transfer coefficient at the corresponding position and accelerating the speed of gas dissolution in the slurry phase.

[0115] Refer to Figure 6As shown, during this reaction process, the gas phase mainly contains carbon dioxide gas. The carbon dioxide gradually dissolves in the slurry phase based on the stirring paddle and reacts with the components in the slurry phase to synthesize cyclic carbonate as the target product, such that the mole fraction of cyclic carbonate in the slurry phase gradually increases with the passage of reaction time.

[0116] Referring to Figure 7 As shown, as an embodiment of the present application, at least one target gas participates in the target reaction process, and the target gas has a gas-liquid dissolution concentration corresponding in the slurry phase, and the gas-liquid dissolution concentration is a scalar; the method further includes:

[0117] S110. Calculate the difference according to the gas-liquid dissolution concentration and the saturated dissolution concentration of the target gas in the slurry phase to obtain the dissolution concentration difference.

[0118] S120. Calculate the mass transfer flux according to the volume mass transfer coefficient and the dissolution concentration difference to obtain the mass transfer flux of the target gas and the slurry phase.

[0119] S130. Numerically represent the mass transfer between the target gas and the slurry phase according to the mass transfer flux and the slurry phase density to obtain the gas-liquid mass transfer source term; wherein, the gas-liquid mass transfer source term represents the mass difference caused by gas-liquid mass transfer during the target reaction process.

[0120] Specifically, in the related art, the process of the gas phase dissolving in the slurry phase is described by mass change, that is, the gas phase loses the mass dissolved in the slurry phase, and the slurry phase increases the mass of the dissolved gas phase. And in the process of solving the physical field equation, the above method will cause the residuals of the continuity equation to be unstable, increasing the difficulty of solving the mass conservation equation. Therefore, to solve the above problems, the present application represents the gas-liquid dissolution concentration corresponding to the target gas in the slurry phase as a scalar, thereby avoiding introducing mass change in the mass conservation equation and reducing the difficulty of its solution.

[0121] Furthermore, by representing the gas-liquid dissolution concentration in the above method, the dissolution of the target gas will not be manifested as a mass change of the gas phase or the slurry phase. Therefore, the mass source term in the physical field equation is obtained according to the gas-liquid dissolution concentration. The gas-liquid mass transfer source term represents the mass difference caused by gas-liquid mass transfer during the target reaction process, and its form is as follows:

[0122]

[0123] Wherein, is the gas-liquid mass transfer source term; is the slurry phase density; is the saturated dissolution concentration of the target gas in the slurry phase; is the gas-liquid dissolution concentration; is the volume mass transfer coefficient, is the contact area between the gas-liquid phases, is the liquid-side mass transfer coefficient, which is calculated using the eddy current model and has the following form:

[0124]

[0125] wherein, is the molecular diffusion coefficient; is the turbulent dissipation rate; is the viscosity of the slurry phase. It can be understood that in the expression of the gas-liquid mass transfer source term, represents the difference in dissolved concentration, represents the mass transfer flux of the target gas and the slurry phase.

[0126] Referring to Figure 8 shown, as an embodiment of the present application, the flow field simulation model includes a multiphase flow model, and the physical field equations corresponding to the multiphase flow model include the continuity equations of each phase. The continuity equations of each phase include the continuity equation of the slurry phase and the continuity equation of the gas phase; the continuity equations of each phase are obtained in the following manner:

[0127] S142. Derive the continuity equation based on the slurry phase mass field data, slurry phase velocity field data, and slurry phase mass transfer source term, and establish the continuity equation of the slurry phase; wherein, the slurry phase mass transfer source term is zero.

[0128] S144. Derive the continuity equation for the gas phase mass field data, gas phase velocity field data, and gas-liquid mass transfer source term, and establish the continuity equation of the gas phase.

[0129] S146. Obtain the continuity equations of each phase based on the continuity equation of the slurry phase and the continuity equation of the gas phase.

[0130] Exemplarily, the multiphase flow model can be established based on the RNGk-ε turbulence model and the Euler-Euler multiphase flow model. The interphase forces between different phases include drag force and turbulent dissipation force. The drag force model selects the Tomiyama model modified by the Brucato model, and the turbulent dissipation force model selects the burns et al model.

[0131] Specifically, the form of the continuity equation of the slurry phase is as follows:

[0132]

[0133] wherein, is the liquid holdup; is the density of the slurry phase; is the velocity of the slurry phase; is the slurry phase mass transfer source term, . In the above formula, Represents the slurry-phase mass field data, that is, the data of the change of the slurry-phase mass over time. Represents the slurry-phase flow velocity field data, that is, the divergence of the mass flux of the slurry phase.

[0134] It should be noted that in this application, since the dissolution of the target gas does not manifest as a change in the mass of the slurry phase, the slurry-phase mass transfer source term is zero, that is, the mass of the slurry phase remains unchanged. When establishing the slurry-phase continuity equation using the gas-liquid dissolution concentration, the mass change caused by the dissolution of the target gas can also be ignored, thereby reducing the computational complexity of the slurry-phase continuity equation and improving the efficiency of numerical simulation.

[0135] Furthermore, the form of the gas-phase continuity equation is as follows:

[0136]

[0137] Where, Is the gas holdup; Is the gas-phase density; Is the gas-phase flow velocity; Is the gas-liquid mass transfer source term. In the above formula, Represents the gas-phase mass field data, that is, the data of the change of the gas-phase mass over time. Represents the gas-phase flow velocity field data, that is, the divergence of the mass flux.

[0138] It should be noted that in actual situations, the mass of the gas dissolved in the slurry phase is very small compared to the overall mass of the slurry phase and can be ignored during calculation. Therefore, in this application, the scalar form of the gas-liquid dissolution concentration is used to represent the dissolution degree of the target gas in the slurry phase, so that the dissolution of the target gas does not manifest as a change in the mass of the slurry phase. However, the gas-phase mass is small, and the part of the gas dissolved in the slurry phase cannot be ignored for the gas phase. In this application, the gas-liquid dissolution concentration is used to obtain the gas-liquid mass transfer source term according to the gas-liquid mass transfer process to represent the mass change of the gas phase.

[0139] Referring to Figure 9 As shown, as an embodiment of this application, the flow field simulation model includes a multiphase flow model, and the physical field equations corresponding to the multiphase flow model further include the momentum balance equations of each phase. The momentum balance equations of each phase include the momentum balance equation of the slurry phase and the momentum balance equation of the gas phase; the momentum balance equations of each phase are obtained in the following manner:

[0140] S152. Derive the dynamic equilibrium equation based on the slurry-phase flow velocity field data, the slurry-phase relative flow momentum transfer data, the slurry-phase-gas-phase interfacial force data, and the slurry-phase mass transfer momentum source term, and establish the slurry-phase momentum balance equation; among them, the slurry-phase mass transfer momentum source term is zero.

[0141] S154. Derive the dynamic equilibrium equation based on the gas-phase velocity field data, gas-phase convective momentum transfer data, gas-phase-slurry phase interfacial force data, and gas-phase mass transfer momentum source term, and establish the gas-phase momentum balance equation; among them, the gas-phase mass transfer momentum source term is obtained by performing momentum calculation based on the gas-liquid mass transfer source term.

[0142] S156. Obtain the momentum balance equations of each phase according to the slurry-phase momentum balance equation and the gas-phase momentum balance equation.

[0143] Specifically, the form of the slurry-phase momentum balance equation is as follows:

[0144]

[0145] Among them, is the pressure; is the slurry-phase viscous stress tensor; is the gravitational acceleration; is the interfacial force between the slurry phase and the gas phase, obtained according to the slurry-phase-gas phase interfacial force data; is the slurry-phase mass transfer momentum source term, . In the above formula, represents the slurry-phase velocity field data, that is, the data of the slurry-phase velocity changing with time, represents the slurry-phase convective momentum transfer data.

[0146] It should be noted that similar to the slurry-phase continuity equation, in actual situations, the mass of the gas dissolved in the slurry phase is very small relative to the overall mass of the slurry phase and can be ignored during calculation. Therefore, in this application, the scalar form of the gas-liquid dissolution concentration is used to represent the dissolution degree of the target gas in the slurry phase, so that the dissolution of the target gas will not be manifested as a change in the mass of the slurry phase. And since the dissolution of the target gas is not manifested as a change in the mass of the slurry phase, the slurry-phase mass transfer momentum source term is zero.

[0147] Furthermore, the form of the gas-phase momentum balance equation is as follows:

[0148]

[0149] Among them, is the gas-phase viscous stress tensor; is the interfacial force between the gas phase and the slurry phase, obtained according to the gas-phase-slurry phase interfacial force data; is the gas-phase mass transfer momentum source term, . In the above formula, represents the gas-phase velocity field data, that is, the data of the gas-phase velocity changing with time, represents the gas-phase convective momentum transfer data.

[0150] It should be noted that, similar to the gas-phase continuity equation, in the present application, the gas-liquid dissolution concentration is utilized, and the gas-liquid mass transfer source term is obtained according to the gas-liquid mass transfer process to represent the mass change of the gas phase. Therefore, the gas-phase mass transfer momentum source term can be obtained by multiplying the gas-liquid mass transfer source term by the gas-phase flow velocity to represent the change in the gas-phase momentum due to gas-liquid mass transfer.

[0151] Referring to Figure 10 shown, as an embodiment of the present application, at least one target gas participates in the target reaction process, and the target gas has a gas-liquid dissolution concentration corresponding in the slurry phase, and the gas-liquid dissolution concentration is a scalar; the reaction simulation model includes a gas-liquid mass transfer model, and the physical field equation corresponding to the gas-liquid mass transfer model includes a scalar transport equation; the scalar transport equation is obtained by the following method:

[0152] S162. Perform gas-liquid mass transfer calculation according to the gas-liquid dissolution concentration and the saturated dissolution concentration of the target gas in the slurry phase to obtain the gas-liquid mass transfer source term of the target gas.

[0153] S164. Based on the gas-liquid dissolution concentration and the concentration of reaction components other than the target gas, calculate the mass change caused by the target reaction process to obtain the chemical reaction source term of the target gas.

[0154] S166. Perform gas-liquid mass transfer equilibrium coupling on the gas-liquid mass transfer source term, the chemical reaction source term, and the concentration field data of the target gas in the slurry phase to obtain the scalar transport equation.

[0155] Specifically, the scalar transport equation represents the mass exchange between the gas phase and the slurry phase in the target reaction process and the mass consumption caused by the chemical reaction in the slurry phase, and its form is as follows:

[0156]

[0157] Among them, is the diffusion coefficient; is the chemical reaction source term. In the above formula, the concentration field data includes , and . Among them, represents the data of the change in the concentration of the target gas in the slurry phase over time, represents the divergence of the convective flux of the concentration of the target gas in the slurry phase, represents the divergence of the diffusion flux of the concentration of the target gas in the slurry phase.

[0158] Referring to Figure 11 shown, as an embodiment of the present application, the chemical reaction source term is obtained by the following method:

[0159] S172. Calculate the reaction rate based on the gas-liquid dissolution concentration of the target gas and the reaction component concentration in the target reaction process to obtain the target reaction rate.

[0160] S174. Calculate the mass change of the target gas in the target reaction process based on the slurry phase density, the relative molecular mass of the reaction components, and the target reaction rate to obtain the chemical reaction source term.

[0161] Specifically, the form of the chemical reaction source term is as follows:

[0162]

[0163] Among them, is the relative molecular mass of the target gas; is the reaction rate, and the reaction rate can be described by the Eley-Rideal model. Exemplarily, its form can be as follows:

[0164]

[0165] Among them, is the reaction rate constant; represents the gas-liquid dissolution concentration; is the concentration of the main component that reacts with the target gas in the slurry phase, is the adsorption equilibrium constant of the main component; is the adsorption equilibrium constant of the target gas; is the other components in the slurry phase, is the adsorption equilibrium constant of the other components, and the other components can include the target product. It should be noted that the chemical reaction source term represents the mass difference caused by the reaction process in the target reaction process. Similarly, there are similar mass source terms for the other components in the slurry phase, and its form is as follows:

[0166]

[0167] Among them, is the mass source term of the other components; is the relative molecular mass of the other components. It can be understood that when applying the reaction rate expressed as above to different types of reaction processes, this formula needs to be adaptively modified.

[0168] It should be noted that since the gas-liquid dissolution concentration corresponding to the target gas in the slurry phase is represented by a scalar, in the physical field equations corresponding to the multi-physical field model in this application, the mass source terms all need to be adaptively modified, including the bubble coalescence model, the bubble breakup model, the finite rate reaction model, and the heat transfer model coupled with the reaction enthalpy change. Among them, the physical field equation corresponding to the finite rate reaction model is the component transport equation, and its form is as follows:

[0169]

[0170] wherein, is the mass fraction of any component in the slurry phase; is the diffusion flux of any component in the slurry phase.

[0171] The heat transfer model coupling the reaction enthalpy change corresponds to the energy equation, and its form is as follows:

[0172]

[0173]

[0174] wherein, represents any phase, including the gas phase and the slurry phase; is the internal energy of any phase; is; is the enthalpy of any phase; is the effective thermal conductivity; is the viscous dissipation coefficient; is the component of the sensible enthalpy; is the component of the diffusion flux; is the energy source term, including the exothermic energy source term caused by the exotherm of the target reaction process and the mass energy source term corresponding to the mass source term. The form of the exothermic energy source term is as follows:

[0175]

[0176] wherein, is the exothermic energy source term; is the reaction enthalpy change of the target reaction process. The form of the mass energy source term is as follows:

[0177]

[0178] wherein, is the mass energy source term; is the specific heat at constant pressure of the target gas; is the temperature of the target gas in the gas phase; is the reference temperature.

[0179] Correspondingly, please refer to Figure 12 , the embodiment of the present application provides a numerical simulation device, and the device includes:

[0180] A simulation model establishment module 1210, configured to establish a numerical simulation model; wherein, the numerical simulation model is used to perform numerical simulation on the target reaction process of synthesizing the target product, the numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model corresponds to reaction dynamic initial conditions.

[0181] The flow field update simulation module 1220 is used to perform fully coupled solutions to the first physical field equation group corresponding to the flow field simulation model and the second physical field equation group corresponding to the reaction simulation model based on the reaction dynamic initial conditions to obtain the flow field update simulation results.

[0182] The flow field stabilization simulation module 1230 is used to separately solve the second physical field equation group based on the flow field update simulation result to obtain the flow field stabilization simulation result when the flow field update simulation result meets the flow field stabilization condition.

[0183] The iterative simulation reaction module 1240 is used to use the flow field stability simulation results as the reaction dynamic initial conditions when the flow field stability simulation results meet the flow field update conditions, and repeatedly execute the steps of fully coupling the first physical field equation group and the second physical field equation group, and separately solving the second physical field equation group until the target reaction process is completed.

[0184] In some optional implementations, the flow field update simulation module 1220 includes:

[0185] The equation group combination unit is used for combining the first physical field equation group and the second physical field equation group to obtain the flow field update equation group.

[0186] The fully coupled solution unit is used to perform fully coupled solution on the flow field update equations using the first time step to obtain the flow field update simulation result.

[0187] The repeated solving unit is used to input the flow field update simulation result as the initial condition into the flow field update equation group, and repeatedly execute the process of fully coupling solving the flow field update equation group until the flow field update simulation result meets the flow field stability condition.

[0188] In some optional embodiments, the flow field stabilization simulation module 1230 includes:

[0189] The separate solving unit is used to separately solve the second physical field equation group using a second time step to obtain a flow field stability simulation result; wherein the second time step is longer than the first time step.

[0190] The repeated solving unit is used to input the flow field stability simulation result as the initial condition into the second physical field equation group, and repeatedly execute the process of separately solving the second physical field equation group until the flow field stability simulation result meets the flow field update condition.

[0191] In some optional embodiments, at least one target gas participates in the target reaction process, and the target gas has a corresponding gas-liquid dissolved concentration in the slurry phase, and the gas-liquid dissolved concentration is a scalar; the simulation model establishment module 1210 includes:

[0192] The dissolved concentration difference calculation unit is used to perform difference calculation based on the gas-liquid dissolved concentration and the saturated dissolved concentration of the target gas in the slurry phase to obtain the dissolved concentration difference.

[0193] The mass transfer mass flux calculation unit is used to calculate the mass transfer flux according to the volume mass transfer coefficient and the difference in dissolved concentration to obtain the mass transfer mass flux of the target gas and the slurry phase.

[0194] The gas-liquid mass transfer source term calculation unit is used to numerically represent the mass transfer between the target gas and the slurry phase according to the mass transfer mass flux and the slurry phase density to obtain the gas-liquid mass transfer source term; wherein the gas-liquid mass transfer source term represents the mass difference caused by gas-liquid mass transfer in the target reaction process.

[0195] In some optional embodiments, the flow field simulation model includes a multiphase flow model, and the physical field equations corresponding to the multiphase flow model include continuity equations of each phase, and the continuity equations of each phase include a slurry phase continuity equation and a gas phase continuity equation; the simulation model establishment module 1210 also includes:

[0196] The slurry phase continuity equation establishing unit is used to derive the continuity equation based on the slurry phase mass field data, the slurry phase velocity field data and the slurry phase mass transfer source term, and establish the slurry phase continuity equation; wherein the slurry phase mass transfer source term is zero.

[0197] The gas phase continuity equation establishing unit is used to derive the continuity equation for the gas phase mass field data, the gas phase velocity field data and the gas-liquid mass transfer source term, and establish the gas phase continuity equation.

[0198] The continuity equation simultaneous unit is used to obtain the continuity equations of each phase based on the slurry phase continuity equation and the gas phase continuity equation.

[0199] In some optional embodiments, the flow field simulation model includes a multiphase flow model, and the physical field equations corresponding to the multiphase flow model also include momentum balance equations of each phase, and the momentum balance equations of each phase include a slurry phase momentum balance equation and a gas phase momentum balance equation; the simulation model establishment module 1210 also includes:

[0200] The slurry phase momentum balance equation establishing unit is used to derive the dynamic balance equation based on the slurry phase velocity field data, the slurry phase-gas phase interaction force data and the slurry phase mass transfer momentum source term, and establish the slurry phase momentum balance equation; wherein the slurry phase mass transfer momentum source term is zero.

[0201] The gas phase momentum balance equation establishment unit is used to derive the dynamic balance equation based on the gas phase velocity field data, the gas phase relative momentum transfer data, the gas phase-slurry phase interaction force data and the gas phase mass transfer momentum source term, and establish the gas phase momentum balance equation; among which, the gas phase mass transfer momentum source term is obtained by momentum calculation based on the gas-liquid mass transfer source term.

[0202] The momentum balance equation simultaneous unit is used to obtain the momentum balance equations of each phase based on the slurry phase momentum balance equation and the gas phase momentum balance equation.

[0203] In some optional embodiments, at least one target gas participates in the target reaction process, and the target gas has a corresponding gas-liquid dissolved concentration in the slurry phase, and the gas-liquid dissolved concentration is a scalar; the reaction simulation model includes a gas-liquid mass transfer model, and the physical field equations corresponding to the gas-liquid mass transfer model include scalar transport equations; the simulation model establishment module 1210 also includes:

[0204] The gas-liquid mass transfer calculation unit is used to perform gas-liquid mass transfer calculation according to the gas-liquid dissolved concentration and the saturated dissolved concentration of the target gas in the slurry phase to obtain the gas-liquid mass transfer source term of the target gas.

[0205] The chemical reaction calculation unit is used to calculate the mass change caused by the target reaction process based on the gas-liquid dissolved concentration and the concentration of the reaction components other than the target gas, and obtain the chemical reaction source term of the target gas.

[0206] The equilibrium simultaneous unit is used to simultaneously balance the gas-liquid mass transfer source term, the chemical reaction source term and the concentration field data of the target gas in the slurry phase to obtain the scalar transport equation.

[0207] In some optional embodiments, the chemical reaction calculation unit includes:

[0208] The reaction rate calculation subunit is used to calculate the reaction rate according to the gas-liquid solution concentration of the target gas and the concentration of the reaction components in the target reaction process to obtain the target reaction rate.

[0209] The mass change calculation subunit is used to calculate the mass change of the target gas during the target reaction process according to the slurry phase density, the relative molecular mass of the reaction components and the target reaction rate to obtain the chemical reaction source term.

[0210] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0211] The numerical simulation device in this embodiment is presented in the form of functional units. Here, the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and a memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0212] Please refer to Figure 13 , Figure 13 , which is a schematic structural diagram of a computer device provided by an embodiment of the present application. As shown in the figure, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Each component communicates with each other using different buses and can be installed on a common motherboard or in other ways as needed. The processor can process instructions executed within the computer device, including instructions stored in the memory or on the memory to display graphical information of the GUI on an external input / output device (such as a display device coupled to the interface). In some alternative embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a set of blade servers, or a multi-processor system). Figure 13 In

[0213] Processor 10 can be a central processing unit, a network processor, or a combination thereof. Among them, processor 10 can further include a hardware chip. The above hardware chip can be an application specific integrated circuit, a programmable logic device, or a combination thereof. The above programmable logic device can be a complex programmable logic device, a field programmable gate array, a generic array logic, or any combination thereof.

[0214] Among them, the memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0215] The memory 20 may include a program storage area and a data storage area. The program storage area may store an operating system and application programs required for at least one function. The data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transitory memory, such as at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some alternative embodiments, the memory 20 may optionally include a memory remotely disposed relative to the processor 10, and these remote memories may be connected to the computer device through a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0216] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk, or a solid-state drive; the memory 20 may further include a combination of the above types of memories.

[0217] The computer device further includes a communication interface 30 for communicating the computer device with other devices or a communication network.

[0218] An embodiment of the present application further provides a computer-readable storage medium. The method according to the embodiment of the present application may be implemented in hardware, firmware, or may be implemented as computer code that can be recorded on a storage medium, or may be implemented as computer code originally stored in a remote storage medium or a non-transitory machine-readable storage medium and downloaded through a network and to be stored in a local storage medium, so that the method described herein may be stored as such software processed on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium may be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, or a solid-state drive, etc.; further, the storage medium may further include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code, and when the software or computer code is accessed and executed by the computer, the processor, or the hardware, the method shown in the above embodiment is implemented.

[0219] An embodiment of the present application provides a computer program product. The computer program product includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. The processor of the computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the method of any embodiment of the present application.

[0220] Although embodiments of the present application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations fall within the scope defined by the appended claims.

[0221] The systems, devices, modules or units illustrated in the above embodiments can be specifically implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, the computer can be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0222] For the convenience of description, when describing the above devices, they are described separately as various units according to their functions. Of course, when implementing the present application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0223] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0224] The present application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the functions specified in Figure 1 one or more flows and / or blocks Figure 1 one or more blocks.

[0225] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device that implements the functions specified in Figure 1 one or more flows and / or blocks Figure 1The functions specified in one or more boxes.

[0226] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide for implementing in the process Figure 1 One process or more processes and / or boxes Figure 1 The steps of the functions specified in one or more boxes.

[0227] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, commodity or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, commodity or device. Without further limitation, an element defined by the statement "comprising one..." does not exclude the presence of additional identical elements in the process, method, commodity or device comprising the said element.

[0228] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0229] The above are only the embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

[0230] Although the embodiments of the present application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A numerical simulation method, characterized in that, The method is used for numerically simulating a long-term reaction process of a target reaction process for synthesizing a target product; the method comprises: Establishing a numerical simulation model; wherein the numerical simulation model is used to numerically simulate a target reaction process for synthesizing a target product, the numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model corresponds to an initial reaction dynamic condition; The physical field model is dynamically adaptively coupled according to the flow field stability, and the corresponding simulation results are obtained through coupled solution until the target reaction process ends. Specifically: based on the initial reaction dynamic conditions, the first physical field equation group corresponding to the flow field simulation model and the second physical field equation group corresponding to the reaction simulation model are fully coupled and solved using a first time step to obtain a flow field update simulation result; when the flow field update simulation result satisfies the flow field stability condition, based on the flow field update simulation result, the second physical field equation group is separately solved using a second time step to obtain a flow field stability simulation result; when the flow field stability simulation result satisfies the flow field update condition, it means that as the target reaction process proceeds, the flow field of the corresponding reaction system gradually moves away from a stable state, and the flow field stability simulation result is used as the initial reaction dynamic condition, and the steps of fully coupled solution of the first physical field equation group and the second physical field equation group, and separately solving the second physical field equation group are repeatedly performed until the target reaction process ends; Among them, the flow field stabilization condition is determined according to the flow field characteristics of the target reaction process, the flow field update condition is determined according to the reaction characteristics of the target reaction process, and the second time step is longer than the first time step; if at the end of the target reaction process, the flow field of the corresponding reaction system is in an unstable state, the flow field update simulation result at this time is used as the final simulation result; if at the end of the target reaction process, the flow field of the corresponding reaction system is in a stable state, the flow field stabilization simulation result at this time is used as the final simulation result.

2. The method according to claim 1, wherein The method of using the first time step to fully couple and solve the first physical field equation group corresponding to the flow field simulation model and the second physical field equation group corresponding to the reaction simulation model to obtain the flow field update simulation result includes: Combining the first physical field equations and the second physical field equations to obtain a flow field update equation group; Using the first time step to perform a fully coupled solution on the flow field update equation group to obtain the flow field update simulation result; The flow field update simulation result is input into the flow field update equation group as an initial condition, and the process of fully coupling solving the flow field update equation group is repeatedly performed until the flow field update simulation result satisfies the flow field stability condition.

3. The method according to claim 2, characterized in that The updating simulation result based on the flow field, solving the second physical field equations separately by using a second time step to obtain a stable flow field simulation result, comprises: The second physical field equations are solved separately using the second time step to obtain the flow field stability simulation result; Input the stable simulation result of the flow field as the initial condition into the second physical field equations, and repeatedly execute the process of separately solving the second physical field equations until the stable simulation result of the flow field meets the flow field update condition.

4. The method according to claim 1, characterized in that At least one target gas is involved in the target reaction process, and the target gas has a gas-liquid dissolution concentration in the slurry phase, and the gas-liquid dissolution concentration is a scalar; the method further includes: Perform a difference calculation based on the gas-liquid dissolution concentration and the saturated dissolution concentration of the target gas in the slurry phase to obtain a dissolution concentration difference. Perform a mass transfer flux calculation based on the volumetric mass transfer coefficient and the dissolution concentration difference to obtain the mass transfer flux of the target gas and the slurry phase. Numerically represent the mass transfer between the target gas and the slurry phase based on the mass transfer flux and the slurry phase density to obtain a gas-liquid mass transfer source term; wherein, the gas-liquid mass transfer source term represents the mass difference caused by gas-liquid mass transfer in the target reaction process.

5. The method according to claim 4, wherein The flow field simulation model includes a multiphase flow model, and the physical field equations corresponding to the multiphase flow model include continuity equations for each phase, and the continuity equations for each phase include a slurry phase continuity equation and a gas phase continuity equation. Obtain the continuity equations for each phase through the following method: Derive a continuity equation based on the slurry phase mass field data, slurry phase velocity field data, and slurry phase mass transfer source term to establish the slurry phase continuity equation; wherein, the slurry phase mass transfer source term is zero. Derive a continuity equation for the gas phase mass field data, gas phase velocity field data, and the gas-liquid mass transfer source term to establish the gas phase continuity equation. Obtain the continuity equations for each phase based on the slurry phase continuity equation and the gas phase continuity equation.

6. The method according to claim 4, characterized in that The flow field simulation model includes a multiphase flow model, and the physical field equations corresponding to the multiphase flow model further include momentum balance equations for each phase, and the momentum balance equations for each phase include a slurry phase momentum balance equation and a gas phase momentum balance equation. Obtain the momentum balance equations for each phase through the following method: Derive a dynamic balance equation based on the slurry phase velocity field data, slurry phase relative flow momentum transfer data, slurry phase-gas phase interfacial force data, and slurry phase mass transfer momentum source term to establish the slurry phase momentum balance equation; wherein, the slurry phase mass transfer momentum source term is zero. Derive a dynamic balance equation based on the gas phase velocity field data, gas phase relative flow momentum transfer data, gas phase-slurry phase interfacial force data, and gas phase mass transfer momentum source term to establish the gas phase momentum balance equation; wherein, the gas phase mass transfer momentum source term is obtained by performing momentum calculation based on the gas-liquid mass transfer source term. Obtain the momentum balance equations for each phase based on the slurry phase momentum balance equation and the gas phase momentum balance equation.

7. The method according to claim 1, wherein At least one target gas is involved in the target reaction process, and the target gas has a gas-liquid dissolution concentration in the slurry phase, and the gas-liquid dissolution concentration is a scalar; the reaction simulation model includes a gas-liquid mass transfer model, and the physical field equations corresponding to the gas-liquid mass transfer model include a scalar transport equation. Obtain the scalar transport equation through the following method: Perform gas-liquid mass transfer calculation based on the gas-liquid dissolution concentration and the saturated dissolution concentration of the target gas in the slurry phase to obtain the gas-liquid mass transfer source term of the target gas; Calculate the mass change caused by the target reaction process based on the gas-liquid dissolution concentration and the concentration of reaction components other than the target gas to obtain the chemical reaction source term of the target gas; Perform gas-liquid mass transfer equilibrium coupling on the gas-liquid mass transfer source term, the chemical reaction source term, and the concentration field data of the target gas in the slurry phase to obtain the scalar transport equation.

8. The method according to claim 7, wherein Obtain the chemical reaction source term through the following method: Calculate the target reaction rate based on the gas-liquid dissolution concentration of the target gas and the concentration of reaction components in the target reaction process; Calculate the mass change of the target gas in the target reaction process based on the slurry phase density, the relative molecular mass of the reaction components, and the target reaction rate to obtain the chemical reaction source term.

9. A numerical simulation device, characterized in that, Used for numerical simulation of the long-term reaction process of the target reaction process for synthesizing the target product; the device includes: A simulation model establishment module for establishing a numerical simulation model; wherein, the numerical simulation model is used for numerical simulation of the target reaction process for synthesizing the target product, the numerical simulation model includes a flow field simulation model and a reaction simulation model, and the numerical simulation model corresponds to reaction dynamic initial conditions; A flow field update simulation module, a flow field stability simulation module, and an iterative simulation reaction module for dynamically adaptively coupling the physical field model according to the flow field stability situation and obtaining corresponding simulation results through coupled solution until the target reaction process ends; wherein, the flow field update simulation module is used to perform full-coupled solution on the first physical field equations corresponding to the flow field simulation model and the second physical field equations corresponding to the reaction simulation model based on the reaction dynamic initial conditions and using the first time step to obtain the flow field update simulation result; the flow field stability simulation module is used to perform separate solution on the second physical field equations based on the flow field update simulation result and using the second time step when the flow field update simulation result meets the flow field stability conditions to obtain the flow field stability simulation result; the iterative simulation reaction module is used to indicate that as the target reaction process progresses, the flow field of the corresponding reaction system gradually deviates from the stable state when the flow field stability simulation result meets the flow field update conditions, and use the flow field stability simulation result as the reaction dynamic initial conditions, and repeat the steps of performing full-coupled solution on the first physical field equations and the second physical field equations and performing separate solution on the second physical field equations until the target reaction process ends; Among them, the flow field stability condition is determined according to the flow field characteristics of the target reaction process, the flow field update condition is determined according to the reaction characteristics of the target reaction process, and the second time step length is longer than the first time step length; if the flow field of the corresponding reaction system is in an unstable state at the end of the target reaction process, the flow field update simulation result at this time is used as the final simulation result; if the flow field of the corresponding reaction system is in a stable state at the end of the target reaction process, the flow field stability simulation result at this time is used as the final simulation result.

10. A computer device, characterized in that, Including: A memory and a processor, the memory and the processor are communicatively connected to each other, computer instructions are stored in the memory, and the processor executes the computer instructions to execute the method according to any one of claims 1 to 8.

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