Phase field model mass conservation correction method and system for two-phase channel turbulence

Abstract

The invention provides a phase field model mass conservation correction method and system for two-phase channel turbulence, and relates to the technical field of two-phase flow numerical calculation, sequence parameters are adopted to describe a current-carrying phase and a dispersed phase in a flow field, the value of a current-carrying phase sequence parameter is 0, and the value of a dispersed phase sequence parameter is 1; comprising the following steps: (1) setting a sequence parameter target total mass M0 according to a mass conservation requirement, the M0 being a volume fraction of a full-field sequence parameter phi i0 at a simulation initial moment, (2) after simulation is started, calculating and updating a sequence parameter phi i (t) of each grid point of the full field at each time step, and (3) determining the total amount delta M (t) of the sequence parameters needing to be corrected according to the difference value between the real-time volume fraction M (t) and the target total mass M0. The method has the advantages that on the basis that an existing solver structure is kept, only the order parameters are operated, the implementation process is simplified, and a mass conservation algorithm which is efficient and easy to implement is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of two-phase flow numerical calculation, and particularly relates to a phase field model mass conservation correction method and system for two-phase channel turbulence. BACKGROUND

[0002] In the method for simulating two-phase flow by using a phase field model, there are many factors affecting mass conservation, such as the truncation operation of the order parameter in the calculation, the dissipative property of the diffuse interface (DI), the role of the diffusion term in the order parameter evolution equation, and the error of the numerical format. In order to improve this problem, two major methods are traditionally adopted, which are as follows: (1) modifying the macro evolution equation of the order parameter; and (2) improving the numerical calculation method (including the improvement of the grid). For the first method, the existing technology proposes various improved methods based on the phase field model. For example, in the evolution process of the order parameter in the flow field, the order parameter is often diffused, the interface thickness is increased, and the function form deviates from the hyperbolic tangent. Therefore, an additional term or a source term is introduced in the modified Cahn-Hilliard (CH) equation, so as to theoretically force the two-phase interface to maintain the hyperbolic tangent profile, thereby reducing the mass loss. This kind of method usually shows good conservation in long-time channel turbulence calculation. Some scholars further propose a flux correction method. They believe that the CH flux J contributes most to the interface normal diffusion, and affects the accuracy and stability of the numerical format, so the normal component Jn of the CH flux along the order parameter contour surface is removed. It is noted that the direction of the Allen-Cahn (AC) flux is the gradient direction of the order parameter, so the essence of this operation is that the flux of the order parameter evolution equation is divided into two parts, in which the normal component of the order parameter contour surface is provided by the AC flux, and the tangential component of the order parameter contour surface is provided by the CH flux. For the second method, some scholars do not modify the macro evolution equation of the order parameter, but improve the accuracy of the numerical algorithm, and use the wENO format to discretize the convection term in the CH equation, and it is found that the mass conservation can also be improved.

[0003] In the prior art, mass non-conservation is a common problem in two-phase flow numerical calculation. Especially in the simulation of the motion of droplets in channel turbulence, the mass conservation problem is more important, mainly in two aspects: on the one hand, the topological change of the droplet interface caused by the complex interaction between the two-phase interface and the turbulence is easy to cause mass deviation; on the other hand, the long-time calculation of the channel turbulence will continuously accumulate the mass loss. Some scholars found that the volume fraction of the droplets often cannot remain constant in the simulation of forced homogeneous isotropic turbulence, and is obviously affected by the initial volume fraction and the Reynolds number and other parameters. The simulation of channel turbulence is similar to this problem, which belongs to two-phase turbulence and needs long-time calculation to obtain statistical quantities, and is therefore challenged by the mass conservation problem.

[0004] In the above-mentioned method (1), since the equation needs to be modified, adjustable parameters are often added, and the effect of improving the numerical result depends on the selection of the parameters. This not only increases the calculation complexity, but also requires the redesign of the solver, thereby increasing the mental burden of researchers and development costs. The method (2) only improves the mass conservation, and the mass non-conservation problem still exists, so it does not solve the problem well. Moreover, the applicability of each method varies with different flow characteristics and model settings, which further increases the difficulty of selection and implementation. SUMMARY

[0005] The present application overcomes the shortcomings in the prior art and provides a phase field model mass conservation correction method and system for two-phase channel turbulent flow, which can directly operate on the order parameter according to the linear relationship between the density and the order parameter, and can ensure strict conservation of droplet mass.

[0006] To solve the above technical problems, the present application is realized by the following technical solutions:

[0007] A phase field model mass conservation correction method for two-phase channel turbulent flow, which uses an order parameter to describe the carrier phase and the dispersed phase in the flow field, wherein the order parameter of the carrier phase is 0, and the order parameter of the dispersed phase is 1; comprising the following steps:

[0008] (1) Set the order parameter target total mass M0 according to the mass conservation requirement, wherein M0 is the volume integral of the order parameter φ i0 at the initial time of simulation:

[0009] M0(φ)=∫ V φ(t=0)dV, M0=∑ i φ i0 V i

[0010] Wherein V i is the volume of the i-th calculation grid point, and φ i0 is the order parameter value of the i-th grid point at the initial time;

[0011] (2) After the simulation starts, calculate and update the order parameter φ i (t) of each grid point in the whole field at each time step, and calculate the real-time volume integral M(t) of the order parameter at this time:

[0012] M(t)=∑ i φ i (t)V i

[0013] (3) Determine the total amount of order parameters to be corrected ΔM(t) by the difference between the real-time volume integral M(t) and the target total mass M0:

[0014] ΔM(t) = M(t) - M0

[0015] (4) According to the specified interface region sequence parameter range (φ1, φ2), the volume V of the interface region at this moment is calculated tot :

[0016] V tot =∑ i V i (φ1<φ i <φ2)

[0017] (5) Using the volume V of each interface region grid point t Divided by the volume V of the entire interface region tot , the volume proportion w of each interface grid point to the entire interface volume is calculated i :

[0018] w i =V i / V tot

[0019] (6) Using the volume proportion w i Multiply the total amount of sequence parameters that need to be corrected ΔM(t), get the sequence parameter correction amount L i (t) required at each grid point of the interface:

[0020] L i (t) = w i ΔM(t)

[0021] (7) Subtract the corresponding sequence parameter correction value L i (t) from the sequence parameter value φ i (t) of the grid point at the interface obtained by simulation at this moment, the sequence parameter value on each grid point after correction can be obtained:

[0022] Φ i (t) = φ i (t) - L i (t).

[0023] Further, the determination method of the sequence parameter target total mass M0 in step (1) comprises:

[0024] (a) Based on the numerical integration calculation of the initialized sequence parameter field; or

[0025] (b) According to the preset mass value of the two-phase flow physical model, independently set.

[0026] Further, the interface sequence parameter range in step (4) can be 0.01 = φ1 < φ2 = 0.99.

[0027] Furthermore, the volume ratio w mentioned in step (5) i Defined as the quality allocation weight coefficient of the interface area grid cell.

[0028] Furthermore, the order parameter described in step (1) is linearly related to the fluid density.

[0029] Furthermore, when other order parameters are used, the order parameters are linearly transformed to a range between 0 and 1 before mass conservation correction is performed.

[0030] Furthermore, in steps (1) and (4), the rectangular method is used to calculate the numerical integration of the order parameters.

[0031] This invention also claims protection for a mass conservation correction system for a phase field model of two-phase channel turbulence, comprising:

[0032] The initialization module is used to set the full-field sequence parameter field according to the initial flow field conditions, and to calculate the initial target mass M0 based on the volume integral of the sequence parameter field, where the current-carrying phase sequence parameter is 0 and the discrete phase sequence parameter is 1.

[0033] The time progression module is used to calculate and update the ordinal parameter φ at each point in the simulation during the simulation process. i (t), calculate the volume integral M(t) of the time series parameters at that time;

[0034] The mass deviation calculation module is used to compare the current order parameter volume fraction M(t) with the initial target mass M0 and calculate the total order parameter ΔM(t) that needs to be corrected.

[0035] The interface recognition module is used to identify the interface region at the current moment according to the preset interface sequence parameter range (φ1, φ2), and calculate the total volume V of the region. tot ;

[0036] The correction allocation module is used to determine the volume ratio w of each grid point in the interface area. i Distribute ΔM(t) proportionally to each interface grid point to obtain the correction amount L at each point. i (t);

[0037] The ordinal parameter correction module is used to adjust the ordinal parameter values ​​φ of the grid points in the interface area. i (t) is corrected to obtain the corrected order parameter value Φ. i (t)=φ i (t)-L i (t);

[0038] The output module is used to apply the corrected order parameter field to subsequent flow field calculations, ensuring mass conservation throughout the field.

[0039] The application also claims an electronic device comprising: a memory for storing instructions executed by one or more processors of the electronic device; and a processor, when the processor executes the instructions in the memory, can make the electronic device implement the steps of any of the above methods.

[0040] Compared with the prior art, the application has the beneficial effects that:

[0041] 1. According to the linear relationship between the density and the order parameter, the order parameter is directly operated, which can ensure the strict conservation of the droplet mass. For some more stringent conditions, such as a large weber number and a complex and disordered droplet distribution, the mass conservation can also be ensured.

[0042] 2. Since the correction amount of the order parameter is only added at the two-phase interface, the influence on the single-phase body region is small.

[0043] 3. The patent only operates on the order parameter, the code implementation is simple, the solver part does not need to be modified, and the mental burden and program development cost of the developer are reduced. BRIEF DESCRIPTION OF DRAWINGS

[0044] The accompanying drawings are used to provide a further understanding of the application, together with the embodiments of the application, to explain the application, and do not constitute a limitation to the application, and in the drawings:

[0045] Figure 1 A flow chart of a mass conservation correction method for calculating two-phase flow based on a phase field model is provided by the application;

[0046] Figure 2 A droplet shape and position diagram when an example using the application is initialized;

[0047] Figure 3 A shape diagram of a program simulation of droplets in a laminar flow after the same time step is calculated;

[0048] Figure 4 A shape diagram of a program simulation of droplets in a turbulent flow field after the same time step is calculated;

[0049] Figure 5 A shape diagram of a program simulation of droplets in a turbulent flow field after the same time step is calculated using the application;

[0050] Figure 6 A comparison of the total mass of the droplets calculated using the application and not using the application after the same time step is calculated. DETAILED DESCRIPTION

[0051] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0052] like Figure 1 As shown, a mass conservation correction method for the phase field model of two-phase channel turbulence is proposed to solve the problem of mass non-conservation in the phase field model when simulating two-phase channel turbulence. By using order parameters to describe the current-carrying phase and discrete phase in the flow field, and performing a series of calculations and corrections on the order parameters, mass conservation in the simulation of two-phase channel turbulence is achieved.

[0053] The flow field is described using order parameters to represent the current-carrying phase and the discrete phase, where the order parameter of the current-carrying phase is set to 0 and the order parameter of the discrete phase is set to 1; the process includes the following steps:

[0054] (1) Set the target total mass M0 according to the mass conservation requirement, where M0 is the order parameter φ of the whole field at the initial moment of the simulation. i0 Volume fraction:

[0055] M0(φ)=∫ V φ(t=0)dV,M0=∑ i φ i0 V i

[0056] Among them, V i For the volume of the i-th calculation grid point, φ i0 The order parameter value is the value of the i-th grid point at the initial time; in this step, the order parameter is linearly related to the fluid density.

[0057] In this step, the determination of the order parameter target total mass M0 includes the following methods:

[0058] (a) Numerical integration based on the initial order parameter field; or

[0059] (b) The mass value is set independently based on the preset mass value of the two-phase flow physical model.

[0060] (2) After the simulation starts, the ordinal parameter φ of all grid points in the field is calculated and updated at each time step. i (t), and calculate the real-time volume integral M(t) of the time series parameters at that time:

[0061] M(t)=∑ i φ i (t)V i

[0062] (3) Determine the total order parameter ΔM(t) to be corrected by the difference between the real-time volume fraction M(t) and the target total mass M0:

[0063] ΔM(t)=M(t)-M0

[0064] (4) Calculate the volume V of the interface region at this moment based on the specified interface region sequence parameter range (φ1, φ2). tot :

[0065] V tot =∑ i V i (φ1<φ i <φ2)

[0066] In this step, the interface sequence parameter range can be 0.01 = φ1 < φ2 = 0.99.

[0067] (5) Use the volume V of each grid point in each interface region t Divide by the total volume of the interface region V tot Calculate the volume percentage w of each interface grid point relative to the total interface volume. i :

[0068] w i =V i / V tot

[0069] In this step, the volume percentage w i Defined as the quality allocation weight coefficient of the interface area grid cell.

[0070] (6) Use volume percentage w i Multiply by the total number of order parameters that need to be corrected, ΔM(t), to obtain the required order parameter correction amount L at each grid point of the interface. i (t):

[0071] L i (t)=w i ΔM(t)

[0072] (7) Simulate the order parameter value φ of the grid point at the interface at this moment. i (t) minus the corresponding order parameter correction value L i (t) yields the corrected order parameter values ​​at each grid point:

[0073] Φ i (t)=φ i (t)-L i (t).

[0074] In steps (1) and (4), the rectangular method is used to calculate the numerical integration of the order parameters.

[0075] When other order parameters are used, the order parameters are linearly transformed to a range between 0 and 1 before mass conservation correction is performed.

[0076] likeFigure 1 The diagram shows a schematic flowchart of the mass conservation algorithm for two-phase channel turbulence provided in an embodiment of the present invention.

[0077] For simplicity, this embodiment uses a uniform grid. The order parameters for the carrier phase and the droplet phase are 0 and 1, respectively, while the order parameter range for the interface region is from 0.01 to 0.99. The simulation example depicts the motion of a droplet in a channel driven by body force. During initialization, a hemispherical droplet is placed on the channel wall, and the calculated data points are located at the center of the grid. The specific implementation process of this method is as follows:

[0078] First, at the start of the simulation, initialization is performed by placing a hemispherical droplet on the channel wall. Based on this initialization condition, the order parameter field φ is obtained by initializing the order parameter field. In phase-field models, density and order parameters are generally set to have a linear relationship. Furthermore, based on the appropriate order parameter settings used in this patent, the value obtained by integrating the order parameter also has a linear relationship with the droplet mass. Therefore, the volume integral of the order parameter is used to replace the mass; as long as the order parameter is conserved, the droplet mass is also conserved. For other order parameter settings, the original order parameters can be linearly transformed to the settings used in this example before calculation. Therefore, the volume integral of the order parameter is numerically calculated using the rectangular method for the entire field, denoted as M0.

[0079] Once the formal simulation begins, the phase-field model used will calculate and update the order parameter φ at each point in time step. i The volume fraction of the time series parameters at that time is calculated and denoted as M(t);

[0080] Subtracting the volume fraction of the sequence parameter M0 at the initial time from the volume fraction of the sequence parameter M(t) at that time, we obtain the total amount of sequence parameter ΔM that needs to be corrected at that time.

[0081] Based on the specified interface region sequence parameter range [0.01, 0.99], the volume V of the interface region is still calculated using the rectangular method of numerical integration. tot ;

[0082] Use the volume V of each grid point in each interface region i Divide by the total volume of the interface region V tot Calculate the volume percentage w of each interface grid point relative to the total interface volume. i ;

[0083] Use the volume percentage of each point in the interface area w i Multiply by the total number of order parameters that need to be corrected, ΔM, to obtain the required order parameter correction amount L at each grid point on the interface. i ;

[0084] The order parameter value φ of the grid point at the interface is calculated at this moment. i Subtract the corresponding system parameter correction value Li The sequence parameter value after the mass conservation correction can be obtained.

[0085] In the numerical simulation, it is found that L is very stable in each iteration except the first step, and generally in the order of , which is very small compared with .

[0086] Table 1 Parameter settings in the test of the modified numerical format of the channel turbulent flow example of the initial single droplet

[0087] Flow regime Mesh Re τ ]] H U τ ]]> v p δx + min ]]> dt we H ]]> Ch H ]]> [D0 / H] Laminar flow 300*600*300 - 150 - 0.0036 1 1 0.5 - 0.04 0.8 Turbulent flow 300*600*300 150 150 0.0036 0.0036 1 1 0.5 0.5 0.04 0.8

[0088] The test parameters are shown in Table 1. The initial velocity field adopted in the turbulent flow field (Turbulent) is a stable turbulent field generated by single-phase flow, and at the time of initialization, a semispherical droplet is placed on the wall, as shown in Figure 2 The only difference between the laminar flow (Laminar) in Table 1 and the turbulent flow is that the initial velocity field of the laminar flow is 0. Therefore, in the laminar flow, there is also a uniform body force pushing the flow field, and the droplet will deform due to the body force in the flow field. In addition, although the droplet diameter D0=0.8H, only half of the sphere, so the volume is 2π(D0 / 2) 3 / 3=0.134H 3 This example is used to compare the evolution of the droplet at the no-slip wall in different flow fields and different correction formats.

[0089] Figures 3 to 5 The visualization result of the droplet shape at t*=1.2 is given. Figure 3 Compared with Figure 4 , it can be seen that in the laminar flow, the droplet only undergoes ordered and regular stretching deformation along the direction of the uniform body force, and at the same time, due to the no-slip effect of the solid wall, the droplet near the wall moves more slowly; while in the turbulent flow field, the disordered effect causes the large droplet to break into multiple small droplets. This comparison can show the complexity of the interaction between the turbulent flow and the two-phase interface. At the same time, it is worth pointing out that the degree of splitting is closely related to the large weber number (We H =5), and if (We H =1), it is difficult to break into multiple sub-droplets due to the strong surface tension effect. Figure 4 , Figure 5 are the same initial conditions (including the turbulent flow field and the droplet), the difference is that Figure 5 the mass correction is performed using the present patent, while Figure 4 no mass correction is performed. By comparing the two, it can be seen that after 10 5After time step, there is no significant difference in the shape and distribution of droplets before and after mass correction. After splitting, the shape of larger droplets is almost the same; the shape and specific position of small droplets have slight differences. In fact, in the numerical calculation of two-phase flow, small structures in the flow field always have differences as long as the numerical format is slightly changed. The influence of the numerical format on large-scale structures can be ignored. Therefore, the simulation results of the above example are reasonable, and the flow field and droplet shape are normal after mass correction using the patent.

[0090] In order to test the mass correction effect of the patent, Figure 6 The total mass of the droplets is compared. The program runs for 10 5 After time step (t* = 1.2), the mass of the laminar example is reduced by 0.06%, the mass of the turbulent example without mass correction is increased by 3.04%, and the mass of the turbulent example with mass correction (Turbulent, Mass Correction) can always keep mass conservation. This shows that for the laminar flow loaded with droplets, even if the mass is not corrected, the conservation type is very good. When the velocity field is turbulent, the unpredictability is enhanced, and it is difficult to guarantee mass conservation. After adding mass correction in the turbulent flow, the conservation is strictly guaranteed, so it is more conservative than the laminar result without correction. The advantage of this mass correction algorithm is that the mass is strictly conserved under this operation. In this way, mass conservation can be guaranteed for some more stringent conditions, such as larger weber number and more complex and disordered droplet distribution. The correction amount is very small at each iteration, so it has little effect on the macro interface. Since the correction amount is added at the two-phase interface, the effect on the single-phase body region will be smaller. In general, this is a more reasonable and effective mass correction method.

[0091] The method is suitable for three-dimensional examples, two-dimensional examples, uniform grids and non-uniform grids; the range of the order parameters of the two phases is not limited to 0 and 1, and the range of the setting of the order parameters of the interface region is also not limited to 0.01 to 0.99, and is also suitable for other cases, and appropriate transformation is needed when numerically calculating the volume integral; the numerical integral calculation used in the example adopts rectangular integral, and other integral methods can also be used to improve the accuracy;

[0092] The application also claims a phase field model mass conservation correction system for two-phase channel turbulent flow, comprising:

[0093] The initialization module is used for setting the order parameter field of the whole field according to the initial flow field condition, and calculating the initial target mass M0 based on the volume integral of the order parameter field, wherein the order parameter of the carrier phase is 0 and the order parameter of the dispersed phase is 1;

[0094] The time advancing module is used for calculating and updating the order parameter φ of each point at the time step during the simulation runningi (t), the volume integral M(t) of the order parameter at the moment is calculated;

[0095] a mass deviation calculation module, configured to compare the order parameter volume integral M(t) at the current moment with the initial target mass M0, and calculate the total amount of order parameter to be corrected ΔM(t);

[0096] an interface identification module, configured to identify the interface region at the current moment according to a preset interface order parameter range (φ1, φ2), and calculate the total volume V of the region tot ;

[0097] a correction amount distribution module, configured to distribute ΔM(t) to each interface grid point in proportion to the volume proportion w i of each grid point in the interface region, to obtain the correction amount L i (t) of each grid point;

[0098] an order parameter correction module, configured to correct the order parameter value φ i (t) of the grid point in the interface region, to obtain the corrected order parameter value Φ i (t) = φ i (t) - L i (t) of each grid point;

[0099] an output module, configured to use the corrected order parameter field for subsequent flow field calculation, to ensure mass conservation in the whole field.

[0100] The application also claims an electronic device, comprising: a memory for storing instructions executed by one or more processors of the electronic device; and a processor, when executing the instructions in the memory, can make the electronic device implement the steps of any of the above methods.

[0101] The electronic device can include one or more of the following components: a processor, a memory, a communication interface, a communication bus. The memory can be connected to the processor through the bus. The bus can transmit data between the processor and the memory. The bus can be divided into an address bus, a data bus, a control bus, etc.

[0102] The processor can include one or more processing cores. The processor can connect various parts in the entire electronic device through various interfaces and lines, execute various functions of the electronic device and process data by running or executing instructions, programs, code sets or instruction sets stored in the memory, and calling data stored in the memory.

[0103] The memory can include random memory, can also include read-only memory, and can also include non-transient computer readable medium. The memory can be used to store instructions, programs, codes, code sets or instruction sets. The memory can include a storage program area and a storage data area, wherein the storage program area can store instructions for implementing an operating system, instructions for at least one function, such as the phase field model mass conservation correction method of two-phase channel turbulent flow, etc.; the storage data area can store data created according to the use of the electronic device, such as input data of numerical solution, etc.

[0104] The mass conservation algorithm provided in the patent does not modify the control equation, but selects a suitable order parameter to represent the two-phase fluid, and realizes the conservation of the order parameter to ensure the mass conservation of the two-phase flow. The order parameter variation part of the whole flow field is uniformly added to the interface area, so that the conservation is strictly guaranteed, and the mass conservation can also be guaranteed under some more stringent conditions, such as larger weber number and more complex and disordered droplet distribution. A uniformly distributed mass source term is added in the two-phase interface area to correct the mass conservation problem. Some scholars add a source term in the Cahn-Hilliard (CH) equation, which will bring new errors in the integration approximation and numerical discretization process; and the correction after numerical iteration in the patent will not bring additional errors. In this way, the expression of the source term is also different, which needs to be redesigned. Specifically, we uniformly subtract a correction amount from the order parameter field in the interface area to satisfy that the integral of the order parameter field over the whole field is constant over time. At the same time, the results show that the correction amount of each iteration is very small when the patent is used, so the influence on the macroscopic interface is small; and since the correction amount is added at the two-phase interface, the influence on the single-phase body area will be smaller. By comparing the motion simulation of the droplet in different flow fields and different correction formats of the channel, for the laminar flow loaded with droplets, the conservation is very good even if the mass is not corrected. When the velocity is turbulent, it is difficult to guarantee the mass conservation; after the mass correction is added, the conservation is strictly guaranteed. Therefore, it is a more reasonable and effective mass correction method. On the basis of maintaining the existing solver structure, only the order parameter is operated to simplify the implementation process, and a mass conservation algorithm which is efficient and easy to implement is realized.

[0105] Finally, it should be noted that: the above is only the preferred embodiment of the present application, and is not used to limit the present application, although the present application is described in detail with reference to the embodiments, for those skilled in the art, the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced, but any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A phase-field model mass conservation correction method for two-phase channel turbulence, characterized in that, The serial parameters are used to describe the carrier phase and the discrete phase in the flow field, wherein the serial parameter of the carrier phase is 0, and the serial parameter of the discrete phase is 1; the method comprises the following steps: (1) Set the total mass M0 of the order parameter according to the mass conservation requirement, which is the initial moment of the whole field order parameter φ i0 Volume integral: M0(φ) = ∫ V φ(t = 0) dV, M0=∑ i φ i0 V i where V i is the volume of the i-th calculation grid point, φ i0 is the order parameter value of the i-th grid point at the initial time; (2) After the simulation starts, the order parameter φ of each lattice point in the whole field is calculated and updated at each time step i (t), and the real-time volume integral M(t) of the order parameter at this moment is calculated: M(t) =∑ i φ i (t)V i (3) The total amount of serial parameters to be corrected ΔM(t) is determined by the difference between the real-time volume integral M(t) and the target total mass M0: ΔM(t) = M(t) - M0 (4) According to the specified interface region sequence parameter range (φ1, φ2), the volume V of the interface region at this moment is calculated tot : V tot =∑ i V i (φ1<φ i <φ2) (5) Using the volume V of each interface region t Divide by the volume V of the entire interface region tot Calculate the volume proportion w of each interface grid point to the entire interface volume i : w i =V i / V tot (6) using the volume fraction w i The total amount of order parameters that need to be corrected ΔM(t) is multiplied by the interface at each lattice site to obtain the order parameter correction L required i (t): L i (t) = w i ΔM(t) (7) The order parameter value φ of the lattice at the interface is obtained by simulation at this moment i (t) The corresponding order parameter correction value L is subtracted i (t), and the order parameter value of each lattice after correction is obtained Φ i (t) = φ i (t) - L i (t).

2. The phase-field model mass-conservation correction method for two-phase channel turbulent flow according to claim 1, characterized in that, The determination method of the serial parameter target total mass M0 in step (1) comprises: (a) numerical integral calculation based on the initialized serial parameter field; or (b) preset mass value independent setting according to the two-phase flow physical model.

3. The phase-field model mass-conservation correction method for two-phase channel turbulence according to claim 1, characterized in that, In step (4), the interface serial parameter range can be 0.01 = φ1 < φ2 = 0.

99.

4. The phase-field model mass-conservation correction method for two- phase channel turbulence according to claim 1, characterized in that, The volume ratio w in step (5) i The mass distribution weight coefficient of the interface region grid cell is defined.

5. The phase-field model mass-conservation correction method for two- phase channel turbulence according to claim 1, characterized in that, In step (1), the serial parameter has a linear relationship with the fluid density.

6. The phase-field model mass-conservation correction method for two- phase channel turbulence according to claim 1, characterized in that, When other serial parameters are used, the serial parameters are linearly transformed to between 0 and 1, and then the mass conservation correction is performed.

7. The phase-field model mass-conservation correction method for two- phase channel turbulence according to claim 1, characterized in that, In steps (1) and (4), the rectangular method is used for calculation when the serial parameters are numerically integrated.

8. A phase-field model mass-conservation correction system for two-phase channel turbulence, characterized in that, Comprise: An initialization module is configured to set a serial parameter field of the whole field according to initial flow field conditions, and calculate an initial target mass M0 based on the volume integral of the serial parameter field, wherein the serial parameter of the carrier phase is 0, and the serial parameter of the discrete phase is 1; a time advancing module for calculating and updating the order parameter φ of each point at the time step during the simulation run i (t), calculating the volume integral M(t) of the order parameter at the time t; A mass deviation calculation module is configured to compare the serial parameter volume integral M(t) at the current time with the initial target mass M0, and calculate the total amount of serial parameters to be corrected ΔM(t); An interface recognition module is configured to recognize an interface region at a current time according to a preset interface sequence parameter range (φ1, φ2), and calculate a total volume V of the region tot ; The correction amount distribution module is configured to distribute the correction amount ΔM(t) to each interface grid point according to the volume proportion w of each interface grid point in the interface region i The correction amount ΔM(t) is proportionally distributed to each interface grid point to obtain the correction amount L of each point i (t) a sequence parameter correction module, configured to correct the sequence parameter value φ i (t) to obtain a corrected sequence parameter value Φ i (t) = φ i (t) - L i (t) An output module is configured to use the corrected serial parameter field for subsequent flow field calculation, and ensure the mass conservation of the whole field.

9. An electronic device, comprising: Comprise: A memory is configured to store instructions executed by one or more processors of the electronic device; When the processor executes the instructions in the memory, the processor can make the electronic device implement the steps of the method in any one of claims 1 to 7.

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