Method and device for predicting boron migration distribution in pressurized water reactor oxide corrosion product deposition layer

Abstract

This invention relates to the field of nuclear reactor technology, specifically to a method and apparatus for predicting boron migration distribution within an oxide corrosion product deposit layer in a pressurized water reactor. The method includes: obtaining the total heat flux density of the outer surface of the oxide corrosion product deposit layer; determining the outer surface temperature of the oxide corrosion product deposit layer based on the distribution principle of the total heat flux density to convective and boiling heat transfer; determining the growth rate of the oxide corrosion product deposit layer and updating its thickness based on the outer surface temperature; determining the temperature distribution within the oxide corrosion product deposit layer according to the outer surface temperature, thickness, and energy conservation equation; and obtaining the boron migration distribution within the oxide corrosion product deposit layer based on the convective-diffusion reaction transport equation and temperature distribution related to boron. This invention enables the prediction of boron migration changes during the growth of an oxide corrosion product deposit layer.

Description

Technical Field

[0001] This invention relates to the field of nuclear reactor technology, and more specifically, to a method and apparatus for predicting the migration and distribution of boron in the deposited layer of oxidation corrosion products in a pressurized water reactor. Background Technology

[0002] During pressurized water reactor (PWR) operation, metal ions and corrosion products from the primary coolant loop deposit on the surface of the fuel cladding in the upper part of the core, forming a thin scale layer known as CRUD (Chalk Rivers Unidentified Deposits). The intensified boiling within the loosely structured CRUD causes boron to precipitate from the coolant and be adsorbed by the porous morphology of the deposit layer, resulting in a non-uniform distribution of boron on the axial surface of the fuel rods. The strong neutron absorption effect of boron can induce core power shift, jeopardizing reactor safety. Therefore, predicting boron migration within the CRUD is crucial for predicting core power shift.

[0003] However, most boron migration prediction methods in related technologies use fixed corrosion product deposit morphology and structure to assess the internal boron migration phenomenon after the formation of the oxidative corrosion product deposit layer, without considering the growth process of the corrosion product deposit layer, resulting in poor accuracy of the prediction results. Summary of the Invention

[0004] The purpose of this invention is to provide a method and apparatus for predicting boron migration distribution within the oxide corrosion product deposit layer of a pressurized water reactor, thereby enabling the prediction of boron migration changes during the growth of the oxide corrosion product deposit layer. This significantly improves the accuracy of boron migration distribution prediction and plays an important role in predicting the core axial power shift phenomenon.

[0005] In a first aspect, the present invention provides a method for predicting the boron migration and distribution within the deposited layer of oxidation corrosion products in a pressurized water reactor, comprising:

[0006] Obtain the total heat flux density of the outer surface of the oxide corrosion product deposit layer;

[0007] Based on the principle of the distribution of the total heat flux density of the outer surface to convective heat transfer and boiling heat transfer, the outer surface temperature of the oxidative corrosion product deposition layer is determined.

[0008] Based on the external surface temperature, the growth rate of the oxide corrosion product deposit layer is determined, and the thickness of the oxide corrosion product deposit layer is updated.

[0009] The temperature distribution within the oxidation corrosion product deposition layer is determined based on the outer surface temperature, the thickness, and the energy conservation equation within the deposition layer.

[0010] Based on the convection-diffusion transport equation for boron within the oxide corrosion product deposit layer and the temperature distribution, the boron migration distribution within the oxide corrosion product deposit layer is obtained.

[0011] In some embodiments, the allocation principle satisfies a power law; determining the outer surface temperature of the oxidative corrosion product deposit layer based on the allocation principle of the total heat flux density of the outer surface for convective heat transfer and boiling heat transfer includes:

[0012] Assume an initial outer surface temperature;

[0013] Based on the initial outer surface temperature and the total heat flux density of the outer surface, the theoretical supercooled boiling heat flux density and the theoretical convective heat flux density of the outer surface of the oxide corrosion product deposition layer are determined.

[0014] Based on the theoretical supercooled boiling heat flux density of the outer surface, the theoretical convective heat flux density of the outer surface, and the total heat flux density of the outer surface, the power-order coupling relationship is determined.

[0015] Based on the total heat flux density of the outer surface, the power coupling relationship, the theoretical supercooled boiling heat flux density of the outer surface, and the theoretical convective heat flux density of the outer surface, the actual supercooled boiling heat flux density and the actual convective heat flux density of the outer surface of the oxidative corrosion product deposition layer are determined respectively.

[0016] If the actual supercooled boiling heat flux density, the actual convective heat flux density, and the total heat flux density of the outer surface satisfy a power law, the initial outer surface temperature is determined as the outer surface temperature; otherwise, the initial outer surface temperature is adjusted to continue the power law verification.

[0017] In some embodiments, determining the growth rate of the oxidation corrosion product deposit layer based on the outer surface temperature includes:

[0018] Based on the external surface temperature and the growth model of the oxide corrosion product deposit layer, the growth rate of the oxide corrosion product deposit layer is determined; wherein, the growth model of the oxide corrosion product deposit layer is used to characterize the growth process of the oxide corrosion product deposit layer.

[0019] In some embodiments, the growth model of the oxide corrosion product deposit layer includes a soluble corrosion product deposition model, a sparingly soluble corrosion product deposition model, and a coolant erosion model; the soluble corrosion product deposition model is used to characterize the mass transfer process of soluble corrosion products in the coolant and the precipitation process of the soluble corrosion products on the cladding surface; the sparingly soluble corrosion product deposition model is used to characterize the mass transfer process of the sparingly soluble corrosion products; the coolant erosion model is used to characterize the erosion effect of the coolant on the deposit; determining the growth rate of the oxide corrosion product deposit layer based on the outer surface temperature and the oxide corrosion product deposition layer growth model includes:

[0020] Based on the external surface temperature, the saturation concentration of soluble corrosion products, the concentration of sparingly soluble corrosion products, the precipitation coefficient of soluble corrosion products, the mass transfer coefficient of sparingly soluble corrosion products, and the coolant shear force are determined.

[0021] Based on the soluble corrosion product deposition model, the saturation concentration of the soluble corrosion product, and the precipitation coefficient of the soluble corrosion product, the deposition rate of the soluble corrosion product is determined.

[0022] Based on the deposition model of the sparingly soluble corrosion products, the concentration of the sparingly soluble corrosion products, and the mass transfer coefficient of the sparingly soluble corrosion products, the deposition rate of the sparingly soluble corrosion products is determined.

[0023] Based on the coolant erosion model and the coolant shear force, the erosion rate of the coolant on the corrosion products is determined.

[0024] The growth rate is determined based on the deposition rate of the soluble corrosion products, the deposition rate of the sparingly soluble corrosion products, and the erosion rate of the corrosion products by the coolant.

[0025] In some embodiments, determining the temperature distribution within the oxidation corrosion product deposition layer based on the outer surface temperature, the thickness, and the energy conservation equation within the oxidation corrosion product deposition layer includes:

[0026] Using the outer surface temperature and the thickness as boundary conditions, the temperature distribution is determined based on the energy conservation equation within the oxide corrosion product deposition layer.

[0027] As one possible implementation, the energy conservation equation within the oxidative corrosion product deposition layer is pre-constructed in the following manner:

[0028] A first heat transfer equation is constructed for the wet region within the oxide corrosion product deposit layer; the wet region refers to the cylindrical region surrounding the chimney within the oxide corrosion product deposit layer.

[0029] A second heat transfer equation is constructed for the surface of the chimney within the oxide corrosion product deposition layer; both the first heat transfer equation and the second heat transfer equation are related to the temperature distribution.

[0030] Based on the first heat transfer equation and the second heat transfer equation, an energy conservation equation for the oxidative corrosion product deposition layer is constructed.

[0031] In some embodiments, the boron migration distribution includes the concentration distribution of various boron solutes within the oxidative corrosion product deposition layer; obtaining the boron migration distribution within the oxidative corrosion product deposition layer based on the convection-diffusion reaction transport equation for boron within the oxidative corrosion product deposition layer and the temperature distribution includes:

[0032] For each boron solute, based on the temperature distribution and at least one chemical reaction in which the boron solute participates, the theoretical concentration distribution of the boron solute after chemical reaction equilibrium is determined for each chemical reaction.

[0033] Based on the theoretical concentration distribution of the boron solute for each of the chemical reactions and the convection-diffusion reaction transport equations, the concentration distribution of the boron-containing solute within the oxidative corrosion product deposition layer is determined.

[0034] A second aspect of the present invention provides a device for predicting the migration and distribution of boron in a pressurized water reactor oxidation corrosion product deposit layer, comprising:

[0035] The acquisition module is used to acquire the total heat flux density of the outer surface of the oxide corrosion product deposit layer;

[0036] The first determining module is used to determine the outer surface temperature of the oxidative corrosion product deposit layer based on the distribution principle of the total heat flux density of the outer surface for convective heat transfer and boiling heat transfer.

[0037] The second determining module is used to determine the growth rate of the oxidation corrosion product deposition layer based on the outer surface temperature, and to update the thickness of the oxidation corrosion product deposition layer.

[0038] The third determining module is used to determine the temperature distribution within the oxidation corrosion product deposition layer based on the outer surface temperature and the thickness, as well as the energy conservation equation within the oxidation corrosion product deposition layer.

[0039] The fourth determining module is used to obtain the boron migration distribution within the oxide corrosion product deposition layer based on the convection-diffusion reaction transport equation for boron within the oxide corrosion product deposition layer and the temperature distribution.

[0040] A third aspect of the present invention provides an electronic device, including a processor and a memory storing a computer program, wherein the processor executes the program to implement the method for predicting the boron migration distribution within the pressurized water reactor oxidation corrosion product deposit layer described in the first aspect above.

[0041] In a fourth aspect, the present invention provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the method for predicting the boron migration distribution within the pressurized water reactor oxidation corrosion product deposit layer as described in the first aspect.

[0042] The method and apparatus for predicting boron migration and distribution within pressurized water reactor oxidation corrosion product deposits provided by this invention have the following beneficial effects:

[0043] This invention couples the growth of the oxide corrosion product deposit layer with the heat and mass transfer phenomena inside the oxide corrosion product deposit layer in real time. By updating the growth of the oxide corrosion product deposit layer and the internal heat and mass transfer in real time, the external surface temperature, thickness and internal temperature distribution of the oxide corrosion product deposit layer can be described more accurately. This allows for a more accurate prediction of the changes in boron migration distribution during the growth of the oxide corrosion product deposit layer, which is of great importance for predicting the core axial power shift phenomenon. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0045] Figure 1 This is a flowchart illustrating a method for predicting boron migration and distribution within a pressurized water reactor oxidation corrosion product deposit layer, as provided in an embodiment of the present invention.

[0046] Figure 2 A flowchart illustrating another method for predicting boron migration and distribution within the deposited layer of pressurized water reactor oxidation corrosion products, provided in an embodiment of the present invention.

[0047] Figure 3 This is an example diagram illustrating the growth mechanism of an oxidation corrosion product deposition layer in an embodiment of the present invention;

[0048] Figure 4 A flowchart illustrating another method for predicting boron migration and distribution within the deposited layer of pressurized water reactor oxidation corrosion products, provided in an embodiment of the present invention.

[0049] Figure 5 This is a schematic diagram of the mass and heat transfer process within the oxide corrosion product deposition layer in an embodiment of the present invention;

[0050] Figure 6 This is a schematic diagram of a device for predicting the migration and distribution of boron in the deposited layer of pressurized water reactor oxidation corrosion products, provided in an embodiment of the present invention.

[0051] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0052] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0053] This invention provides a method and apparatus for predicting boron migration distribution within the oxide corrosion product deposit layer of a pressurized water reactor. By coupling the growth process of the oxide corrosion product deposit layer with the heat and mass transfer phenomena within the oxide corrosion product deposit layer, and combining the mutual influence between the two, the method achieves accurate prediction of boron migration distribution during the growth process of the oxide corrosion product deposit layer.

[0054] Figure 1 This is a flowchart illustrating a method for predicting boron migration and distribution within a pressurized water reactor oxidation corrosion product deposit layer, as provided in an embodiment of the present invention. Figure 1 As shown, the method includes the following steps:

[0055] Step 101: Obtain the total heat flux density of the outer surface of the oxidative corrosion product deposit layer.

[0056] In some embodiments, the total heat flux density of the outer surface of the oxide corrosion product deposit layer can be calculated based on formulas in related technologies, or it can be information entered by relevant personnel based on an interactive interface.

[0057] It should be noted that steps 101 to 105 in the embodiments of the present invention can be executed in real time or at set intervals according to a preset time step.

[0058] Step 102: Determine the outer surface temperature of the oxidative corrosion product deposit layer based on the principle of distribution of total heat flux density on the outer surface to convective heat transfer and boiling heat transfer.

[0059] In some embodiments, the total heat flux density of the outer surface is distributed to both convective heat transfer and boiling heat transfer according to a power law. Therefore, the outer surface temperature of the oxidation corrosion product deposit layer can be determined based on the distribution principle of the total heat flux density of the outer surface to convective and boiling heat transfer. The surface of the oxidation corrosion product deposit layer has two sides: one side is the surface in contact with the cladding, and the other side is the surface close to the main coolant. In the embodiments of the present invention, the outer surface temperature refers to the temperature of the surface of the oxidation corrosion product deposit layer on the side closest to the main coolant.

[0060] As one possible implementation, the distribution principle of the total heat flux density on the outer surface for convective and boiling heat transfer follows a power law. Based on this principle, the process of determining the outer surface temperature of the oxide corrosion product deposition layer can be achieved through the following steps:

[0061] Step S1, assuming the initial outer surface temperature.

[0062] The initial outer surface temperature can be an assumed value, such as a value given based on experience or a randomly selected value.

[0063] Step S2: Based on the initial outer surface temperature, determine the theoretical supercooled boiling heat flux density and the theoretical convective heat flux density of the outer surface of the oxide corrosion product deposition layer.

[0064] The theoretical supercooled boiling heat flux density of the outer surface of the oxide corrosion product deposit layer refers to the theoretical supercooled boiling heat flux density of the outer surface of the oxide corrosion product deposit layer under conditions where convective heat transfer does not occur. The theoretical convective heat flux density of the outer surface of the oxide corrosion product deposit layer refers to the theoretical supercooled boiling heat flux density of the outer surface of the oxide corrosion product deposit layer under conditions where convective heat transfer does not occur.

[0065] In some embodiments, the theoretical convective heat flux density of the outer surface of the oxide corrosion product deposit layer is calculated based on the initial outer surface temperature using the following formula (1).

[0066] (1)

[0067] in, The theoretical convective heat flux density of the outer surface of the oxidative corrosion product deposit layer; The convective heat transfer coefficient; This refers to the near-wall coolant temperature. This is the initial outer surface temperature.

[0068] In some embodiments, the process of determining the theoretical supercooled boiling heat flux density of the outer surface of the oxide corrosion product deposit layer based on the initial outer surface temperature is shown in Equations (2) and (3) below.

[0069] (2);

[0070] (3);

[0071] in, This is the theoretical value of the critical superheat under conditions where convective heat transfer does not occur; This is the critical superheat, an empirical value. The theoretical supercooled boiling heat flux density of the outer surface of the oxide corrosion product deposit layer; This refers to the coolant pressure. This is the saturation temperature of the mainstream coolant region.

[0072] Step S3: Determine the power-law coupling relationship based on the theoretical supercooled boiling heat flux density of the outer surface, the theoretical convective heat flux density of the outer surface, and the total heat flux density of the outer surface.

[0073] In some embodiments, the theoretical supercooled boiling heat flux density of the outer surface, the theoretical convective heat flux density of the outer surface, and the total heat flux density of the outer surface satisfy the following equation (4), thus an n-power coupling relationship satisfying the following equation (4) can be obtained.

[0074] (4);

[0075] Step S4: Based on the total heat flux density of the outer surface, the power coupling relationship, the theoretical supercooled boiling heat flux density of the outer surface, and the theoretical convective heat flux density of the outer surface, determine the actual supercooled boiling heat flux density and the actual convective heat flux density of the outer surface of the oxidative corrosion product deposit layer.

[0076] In some embodiments, the actual supercooled boiling heat flux density of the outer surface of the oxide corrosion product deposit layer can be calculated by the following formula (5) based on the total heat flux density of the outer surface, the power coupling relationship and the theoretical supercooled boiling heat flux density of the outer surface.

[0077] (5);

[0078] in, The actual supercooled boiling heat flux density of the outer surface of the oxide corrosion product deposit layer under convective heat transfer conditions.

[0079] In some embodiments, the actual convective heat transfer density of the outer surface of the oxide corrosion product deposit layer can be calculated by the following formula (6) based on the total heat flux density of the outer surface, the power coupling relationship and the theoretical convective heat transfer density of the outer surface.

[0080] (6);

[0081] in, The actual convective heat flux density on the outer surface of the oxide corrosion product deposit layer under conditions that prevent supercooling and boiling.

[0082] Step S5: If the actual supercooled boiling heat flux density, the actual convective heat flux density, and the total heat flux density of the outer surface satisfy the power law, the initial outer surface temperature is determined as the outer surface temperature; otherwise, the initial outer surface temperature is adjusted and the power law verification is continued.

[0083] In some embodiments, it can be determined whether the actual supercooled boiling heat flux density, the actual convective heat flux density, and the total heat flux density of the outer surface satisfy the following equation (7). If the following equation (7) is satisfied, it is considered to satisfy the power law, and the initial outer surface temperature is determined as the outer surface temperature at the current moment; if the following equation (7) is not satisfied, it is considered to not satisfy the power law, and the initial outer surface temperature is adjusted, and the process returns to continue executing step S2. The outer surface temperature at the current moment is obtained by iterating repeatedly through steps S1 to S5.

[0084] (7);

[0085] Step 103: Based on the external surface temperature, determine the growth rate of the oxide corrosion product deposit layer and update the thickness of the oxide corrosion product deposit layer.

[0086] It is understandable that the surface temperature of the oxide corrosion product deposit layer at the current moment will affect the chemical balance between solutes in the near-wall coolant, as well as the solute concentration and the deposition of corrosion products, thus affecting the growth of the oxide corrosion product deposit layer.

[0087] In some embodiments, a pre-defined neural network model can be used. The thickness of the oxide corrosion product deposit layer at the previous moment and the outer surface temperature at the current moment are input into the neural network model. The neural network model outputs the growth rate of the oxide corrosion product deposit layer at the current moment, and then updates the thickness of the oxide corrosion product deposit layer based on the growth rate at the current moment. The neural network model has learned the mapping relationship between the thickness of the oxide corrosion product deposit layer at the previous moment, the surface temperature at the current moment, and the growth rate at the current moment.

[0088] In other embodiments, the parameters related to the mass transfer process outside the oxide corrosion product deposit layer can be calculated based on the current external surface temperature. Based on the parameters related to the mass transfer process, the mass transfer equation outside the oxide corrosion product deposit layer, and the chemical reactions occurring in the coolant, the growth rate of the corrosion product deposit layer can be calculated. Combined with the thickness at the previous moment, the thickness of the oxide corrosion product deposit layer at the current moment can be obtained.

[0089] Step 104: Determine the temperature distribution within the oxide corrosion product deposition layer based on the outer surface temperature and thickness, and the energy conservation equation within the oxide corrosion product deposition layer.

[0090] In some embodiments, the thickness of the oxide corrosion product deposit layer can refer to the outer boundary of the oxide corrosion product deposit layer, and the outer surface temperature of the oxide corrosion product deposit layer can refer to the temperature at the outer boundary of the oxide corrosion product deposit layer. Therefore, the current outer surface temperature and thickness can be used as boundary conditions, and the temperature distribution at the current moment can be determined based on the energy conservation equation within the oxide corrosion product deposit layer.

[0091] The energy conservation equation within the oxide corrosion product deposit layer is constructed based on the heat transfer process within the layer. The temperature distribution within the oxide corrosion product deposit layer refers to the temperature at different spatial locations within the layer.

[0092] It should be noted that after the deposition of the oxidation and corrosion product layer, if there is no internal boiling, the internal heat transfer of the oxidation and corrosion product layer is solved through single-phase heat conduction. In the case of internal boiling, local boiling inside the deposition layer causes mass evaporation in the form of steam.

[0093] In some embodiments, the energy conservation equation within the oxidative corrosion product deposit layer can be pre-constructed, and the construction process includes:

[0094] Step S6: Construct the first heat transfer equation for the wet zone within the oxide corrosion product deposit layer; the wet zone refers to the cylindrical region surrounding the chimney within the oxide corrosion product deposit layer.

[0095] It should be noted that heat transfer, capillary flow, solute mass transfer, and chemical reactions within the oxide corrosion product deposit layer are closely coupled. Under the influence of capillary forces, the coolant enters the interior of the oxide corrosion product deposit layer, undergoes supercooled boiling on the chimney surface to form steam, and escapes from the oxide corrosion product deposit layer through its unique chimney structure. To distinguish the different locations of steam and coolant within the oxide corrosion product deposit layer, the chimney area is called the dry zone, while the cylindrical shell surrounding it is called the wet zone.

[0096] In some embodiments, the first heat transfer equation can be expressed as equation (8). In equation (8)... The results are obtained by calculation using the following formulas (9) to (13).

[0097] (8);

[0098] (9);

[0099] (10);

[0100] (11);

[0101] (12);

[0102] (13);

[0103] in, The total thermal conductivity is the weighted average of solid and liquid thermal conductivity within the CRUD wet zone. It refers to the temperature distribution within the deposited layer of oxidation and corrosion products; It is the heat carried away by the boiling on the surface of the chimney; Porosity; The process variable for solving the overall thermal conductivity is the series thermal conductivity component in the thermal conductivity based on the fractal dimension; It is the process variable for solving the overall thermal conductivity, and it is the parallel thermal conductivity component in the thermal conductivity based on the fractal dimension; and These are the thermal conductivity coefficients of the metal oxide framework and the coolant, respectively. and These are the maximum and minimum pore sizes of the oxidative corrosion product deposit layer, respectively. and These are the fractal dimension and tortuous fractal dimension of the oxidative corrosion product deposition layer, respectively; It is the characteristic length of the deposited layer of oxidation and corrosion products.

[0104] Step S7: Construct the second heat transfer equation on the surface of the chimney within the oxide corrosion product deposit layer; both the first and second heat transfer equations are related to the temperature distribution.

[0105] In some embodiments, the expression for the second heat transfer equation is shown in equation (14) below, wherein the relevant parameters are calculated by equations (15) to (24) below.

[0106] (14);

[0107] (15);

[0108] (16);

[0109] (17);

[0110] (18);

[0111] (19);

[0112] (20);

[0113] (twenty one);

[0114] (twenty two);

[0115] (twenty three);

[0116] (twenty four);

[0117] in, It is the evaporation coefficient; It is the molar mass of water; It is the ideal gas constant; It is the latent heat of vaporization of the coolant; and These are the molar volumes of water vapor and water, respectively. and These are the chimney radius and chimney density, respectively. It is the permeability of the oxide corrosion product deposit layer; It is the evaporative heat transfer coefficient of water on the surface of the chimney; It is the saturation temperature; It is the saturation temperature coefficient, which is a constant. It is the reactivity coefficient of water; It is the molality of water, a constant value of 55.51 mol / kg; It is the molality of the solute. This represents the boron migration distribution at the previous moment; It is the density of the coolant; It is the density of the vapor after the coolant evaporates.

[0118] Step S8: Based on the first heat transfer equation and the second heat transfer equation, construct the energy conservation equation for the oxidative corrosion product deposition layer.

[0119] In some embodiments, the first heat transfer equation shown in equation (8) and the second heat transfer equation shown in equation (14) constitute the energy conservation equation for the oxidative corrosion product deposit layer.

[0120] In some embodiments, temperature distribution calculations can be performed using a grid partitioning method for discrete calculations.

[0121] Step 105: Based on the convection-diffusion reaction transport equation and temperature distribution of boron in the oxide corrosion product deposit layer, the boron migration distribution in the oxide corrosion product deposit layer is obtained.

[0122] In some embodiments, H3BO3, Li+, and B(OH) 4-Solutes, including boron, enter the oxidation corrosion product deposit layer along with the coolant and are continuously concentrated. A chemical equilibrium is maintained among the various solutes. The chemical reactions involving boron are shown in equations (25) to (28). The coolant, under capillary action,... The coolant enters the CRUD at a high speed, bringing with it solutes such as boric acid (H3BO3) and lithium hydroxide (LiOH). Under the combined effects of convection caused by the coolant flow, diffusion driven by chemical potential, and migration of charged particles by the electric field, the solutes are continuously concentrated while maintaining the chemical equilibrium between them. The convective-diffusion transport equation for boron within the oxidative corrosion product deposit layer is shown in equation (29).

[0123] (25);

[0124] (26);

[0125] (27);

[0126] (28);

[0127] (29);

[0128] (30);

[0129] in, It is the concentration of the i-th boron-containing solute in the coolant; It is the theoretical concentration of the i-th boron-containing solute in the coolant after it reaches chemical equilibrium in the k-th chemical reaction it participates in; The number of chemical reactions in which the i-th boron-containing solute participates; diffusion coefficient. The diffusion coefficient in pure water needs to be determined based on fractal theory. Make the correction as shown in equation (30) above, where It refers to the tortuosity of the deposited dirt layer.

[0130] In some embodiments of the present invention, the boron migration distribution includes the concentration distribution of various boron-containing solutes within the oxide corrosion product deposition layer. The implementation of step 105 may include the following steps: for each boron-containing solute, based on the temperature distribution and at least one chemical reaction in which the boron-containing solute participates, determine the theoretical concentration distribution of the boron-containing solute for each chemical reaction after chemical reaction equilibrium; based on the theoretical concentration distribution of the boron-containing solute for each chemical reaction and the convection-diffusion reaction transport equation, determine the concentration distribution of the boron-containing solute within the oxide corrosion product deposition layer. That is, by substituting the theoretical concentration distribution of the boron-containing solute for each chemical reaction and the concentration distribution of the boron-containing solute at the previous moment into the convection-diffusion reaction transport equation shown in equation (29) above, the concentration distribution of the boron-containing solute within the oxide corrosion product deposition layer at the current moment is obtained.

[0131] The boron migration distribution prediction method within the pressurized water reactor oxidation corrosion product deposit layer according to embodiments of the present invention, by coupling the growth of the oxidation corrosion product deposit layer with the heat and mass transfer phenomena inside the oxidation corrosion product deposit layer in real time, and by updating the growth of the oxidation corrosion product deposit layer and the internal mass and heat transfer in real time, can more accurately describe the outer surface temperature, thickness, and internal temperature distribution of the oxidation corrosion product deposit layer. This allows for more accurate prediction of the changes in boron migration distribution as the oxidation corrosion product deposit layer grows, which plays an important role in predicting the core axial power shift phenomenon.

[0132] Figure 2 This is a schematic flowchart illustrating another method for predicting boron migration and distribution within the deposited layer of pressurized water reactor oxidation corrosion products, provided in an embodiment of the present invention. Figure 2 As shown, based on the above embodiments, Figure 1 The implementation process of step 103 includes the following steps:

[0133] Step 201: Determine the growth rate of the oxide corrosion product deposit layer based on the external surface temperature and the growth model of the oxide corrosion product deposit layer; wherein, the growth model of the oxide corrosion product deposit layer is used to characterize the growth process of the oxide corrosion product deposit layer.

[0134] In some embodiments, the oxide corrosion product deposit layer can be a neural network model that has learned the mapping relationship between the outer surface temperature of the oxide corrosion product deposit layer and its growth rate. The current outer surface temperature and the thickness at the previous time step are input into the oxide corrosion product deposit layer growth model to obtain the growth rate at the current time output by the oxide corrosion product deposit layer growth model.

[0135] The growth rate can be either the rate of change of thickness or the rate of mass increase.

[0136] In some embodiments, the oxidation corrosion product deposition layer growth model can characterize the deposition process of soluble corrosion products and the deposition process of insoluble corrosion products in the coolant. Based on the current external surface temperature and the oxidation corrosion product deposition layer growth model, the precipitation rate of soluble corrosion products and the deposition rate of insoluble corrosion products can be obtained. Based on the precipitation rate of soluble corrosion products and the deposition rate of insoluble corrosion products, the growth rate at the current moment can be obtained.

[0137] Step 202: Update the thickness of the oxidative corrosion product deposit layer.

[0138] In some embodiments, if the growth rate is the mass growth rate of the oxidative corrosion product deposit layer per unit area, the thickness at the current moment can be calculated using the following formula (31) based on the thickness and growth rate at the previous moment.

[0139] (31);

[0140] in, The thickness of the oxidative corrosion product deposit layer; t represents the start time of deposition; t represents the current time. Growth rate; It is the density of the deposited layer of oxidation and corrosion products.

[0141] The boron migration distribution prediction method in the pressurized water reactor oxidation corrosion product deposit layer according to the present invention introduces an oxidation corrosion product deposit layer growth model, which can calculate the thickness of the oxidation corrosion product deposit layer in real time. Therefore, heat and mass transfer calculations can be performed based on the updated thickness of the oxidation corrosion product deposit layer to obtain a more accurate boron migration distribution.

[0142] In some embodiments, supercooled nucleus boiling is the driving force for the deposition of most corrosion products on the fuel cladding. The oxidative corrosion product deposit is formed via a soluble / particle transport mechanism, a combination of soluble precipitation and particle aggregation. Under supercooled boiling conditions, soluble corrosion products first reach supersaturation at the gas-liquid interface, precipitating as particles, and then agglomerate with insoluble particles present in the coolant and are transported together. Simultaneously, the chemical equilibrium among various solutes is affected by temperature, thereby altering the solute concentration.

[0143] In some embodiments, sparingly soluble corrosion products are considered to be deposited on the fuel cladding via mass transfer, while soluble corrosion products first reach saturation or react with other ions, precipitating as particles and then depositing on the fuel cladding via mass transfer. Due to the erosive effect of the high-speed flow field, particles on the surface of the deposited layer can also enter the coolant. When deposition and erosion reach a dynamic equilibrium, the oxidative corrosion product deposit layer exhibits no further macroscopic growth. Figure 3This is an example diagram illustrating the growth mechanism of an oxidation corrosion product deposition layer in an embodiment of the present invention, such as... Figure 3 As shown, soluble substances and particles (insoluble substances) in the main coolant enter the near-wall coolant through mass transfer. The soluble substances reach saturation on the surface of the deposit layer or react with other ions, precipitate and deposit, and are deposited on the fuel cladding through mass transfer. The particles are deposited on the fuel cladding through mass transfer, resulting in the continuous growth of the oxidative corrosion product deposit layer.

[0144] Due to the ionization of water in the coolant, hydroxide ions combine with metal cations to form hydroxides, and different metal hydroxides have different deposition sensitivities. In the above process, the change in the outer surface temperature of the oxidative corrosion product deposit layer affects the chemical balance between solutes in the near-wall coolant, and also affects the solute concentration and corrosion product deposition, thereby affecting the growth of the oxidative corrosion product deposit layer. Therefore, it is necessary to consider the influence of the chemical reactions present in the coolant on the growth of the oxidative corrosion product deposit layer. The relevant deposition model does not consider H3BO3, LiOH and H2, and the results are all derived from the pH value of the assumed pure B-Li-H2O system. However, Fe and Ni also affect the pH and other conditions of the coolant, and thus affect their own solubility. In some embodiments of the present invention, the chemical reactions in the coolant considered are shown in the following equations (32) to (42), and the above equations (25) to (28).

[0145] (32);

[0146] (33);

[0147] (34);

[0148] (35);

[0149] (36);

[0150] (37);

[0151] (38);

[0152] (39);

[0153] (40);

[0154] (41);

[0155] (42);

[0156] Figure 4This is a flowchart illustrating another method for predicting boron migration and distribution within a pressurized water reactor oxidation corrosion product deposit layer, provided in an embodiment of the present invention. In this embodiment, the oxidation corrosion product deposit layer growth model includes a soluble corrosion product deposition model, a sparingly soluble corrosion product deposition model, and a coolant erosion model. The soluble corrosion product deposition model characterizes the mass transfer process of soluble corrosion products in the coolant and the precipitation process of soluble corrosion products on the cladding surface. The sparingly soluble corrosion product deposition model characterizes the mass transfer process of sparingly soluble corrosion products. The coolant erosion model characterizes the erosion effect of the coolant on the deposits.

[0157] Based on the growth process of the oxidation and corrosion product deposit layer, the mass and heat transfer processes within the oxidation and corrosion product deposit layer are as follows: Figure 5 As shown, corrosion products are deposited on the cladding surface, and the coolant erodes the deposits. Coolant-soluble substances such as boric acid and lithium hydroxide enter the interior of the oxidation corrosion product deposit layer via Darcy flow caused by internal boiling. When the coolant evaporates on the chimney surface, the soluble components concentrate to a supersaturated state and eventually precipitate within the oxidation corrosion product deposit layer. The heat carried away by chimney boiling within the oxidation corrosion product deposit layer, along with heat conduction in the wet zone, constitutes an energy conservation within the oxidation corrosion product deposit layer.

[0158] like Figure 4 As shown, based on the above embodiments, Figure 2 The implementation process of step 201 includes the following steps:

[0159] Step 401: Based on the external surface temperature, determine the saturation concentration of soluble corrosion products, the concentration of insoluble corrosion products, the precipitation coefficient of soluble corrosion products, the mass transfer coefficient of insoluble corrosion products, and the coolant shear force.

[0160] The soluble corrosion products in the coolant may include the soluble substances in the above chemical reaction equations, such as Fe. 2+ FeOH + Fe(OH)2, Fe(OH)3 - Ni 2+ NiOH +- The insoluble corrosion products in the coolant may include nickel ferrite (NiFe2O4), iron oxide (Fe3O4), and nickel oxide (NiO), etc.

[0161] In some embodiments, soluble corrosion products can be precipitated by the chemical reactions shown in equations (39) and (40) above, and the precipitation coefficient of soluble corrosion products can be calculated by equation (43) below.

[0162] (43);

[0163] (44);

[0164] in, It is the precipitation coefficient of soluble corrosion products; It is the constant of the precipitation coefficient of soluble corrosion products. It is the activation energy of the precipitation reaction, which can be solved by the above equation (44). It is the ideal gas constant. It is the near-wall coolant temperature. It is the pre-exponential factor in the Arrhenius equation for precipitation reactions. It is the precipitation reaction equilibrium constant, which can be the average of the chemical reaction equilibrium constants shown in equation (39) and (40) above, or any one of the chemical reaction equilibrium constants shown in equation (39) and (40) above. The chemical reaction equilibrium constant is determined based on the external surface temperature at the current moment.

[0165] In some embodiments, the mass transfer coefficient of the sparingly soluble corrosion products can be calculated using equations (45) to (48). The concentration of the sparingly soluble corrosion products can be determined based on the chemical reaction equilibrium constant determined by the external surface temperature at the current moment.

[0166] (45);

[0167] (46);

[0168] (47);

[0169] (48);

[0170] in, It is the mass transfer coefficient of sparingly soluble corrosion products. and These are the Sherwood number and the Schmitt number for mass transfer of sparingly soluble corrosion products, respectively. It is the diffusion coefficient of sparingly soluble corrosion products. It is Boltzmann's constant. It is the particle radius of the sparingly soluble corrosion products, which can be the average value of the particle radius of the sparingly soluble corrosion products; It is the density of the coolant. It refers to the viscosity of the coolant; , , , and The values ​​are all corresponding to the current external surface temperature.

[0171] Since the coolant shear force is also related to the outer surface temperature of the oxide corrosion product deposit layer, the coolant shear force at the current moment can be calculated based on the outer surface temperature of the oxide corrosion product deposit layer. The calculation method for coolant shear force is consistent with the calculation method in related technologies, and will not be repeated here.

[0172] Step 402: Determine the deposition rate of soluble corrosion products based on the soluble corrosion product deposition model, the saturation concentration of soluble corrosion products, and the precipitation coefficient of soluble corrosion products.

[0173] In some embodiments, driven by coolant turbulence and concentration difference, the mass transfer equations for the transfer of soluble corrosion products from the coolant to the cladding surface are shown in equations (49) to (53). Driven by supercooled boiling, the coolant near the cladding wall becomes supersaturated, and soluble corrosion products precipitate, as shown in equation (54). When precipitation and mass transfer reach a steady state, equation (55) is satisfied. Combining equations (49) and (54) above, the soluble corrosion product deposition model shown in equation (56) is obtained.

[0174] (49);

[0175] (50);

[0176] (51);

[0177] (52);

[0178] (53);

[0179] in, It is the mass transfer quality of soluble corrosion products. It is the mass transfer coefficient of soluble corrosion products. and These are the concentrations of soluble corrosion products in the mainstream coolant zone and the concentrations of soluble corrosion products near the wall surface. , and These are the Sherwood number, Reynolds number, and Schmitt number for the mass transfer of soluble corrosion products. It is the diffusion coefficient of soluble corrosion products. It is the equivalent diameter of the coolant channel. It is the density of the coolant. It is the coolant flow rate. It is the viscosity of the coolant. The parameters in equations (49) to (53) above are all determined based on the temperature of the mainstream coolant zone.

[0180] (54);

[0181] (55);

[0182] (56);

[0183] in, It refers to the quality of soluble corrosion product precipitation. It is the precipitation coefficient of soluble corrosion products. It is the saturation concentration of soluble corrosion products. It is the deposition rate of soluble corrosion products. It is the code for soluble corrosion products, including Fe. 2+ FeOH + Fe(OH)2, Fe(OH)3 - Ni 2+ NiOH + Fe(OH)2, Fe(OH)3 - wait.

[0184] In other words, by substituting the saturation concentration of the soluble corrosion product and the precipitation coefficient of the soluble corrosion product determined in step 402 into the above formula (56), the deposition rate of the soluble corrosion product is obtained.

[0185] Step 403: Determine the deposition rate of sparingly soluble corrosion products based on the deposition model of sparingly soluble corrosion products, the concentration of sparingly soluble corrosion products, and the mass transfer coefficient of sparingly soluble corrosion products.

[0186] It should be noted that, unlike soluble corrosion products, the mass transfer behavior of particles in coolant is controlled by Brownian motion. For small particles that can enter the reactor core, since the particle adhesion probability is close to 1, once the particles reach the cladding surface or the outer surface of the oxide corrosion product deposit layer, they detach from the coolant and adhere to the surface of the oxide corrosion product deposit layer.

[0187] In some embodiments of the present invention, the deposition model of the sparingly soluble corrosion products is shown in the following formula (57). The concentration of the sparingly soluble corrosion products and the mass transfer coefficient of the corrosion products obtained in step 401 are substituted into the following formula (57) to obtain the deposition rate of the sparingly soluble corrosion products at the current time.

[0188] (57);

[0189] in, The deposition rate of sparingly soluble corrosion products; For the first The concentration of sparingly soluble corrosion products.

[0190] Step 404: Based on the coolant erosion model and coolant shear force, determine the erosion rate of the coolant on the corrosion products.

[0191] In some embodiments, the coolant erosion model is shown in equations (58) and (59) below. Substituting the thickness at the previous moment and the coolant shear force obtained in step 401, the erosion rate of the coolant on the corrosion products is obtained.

[0192] (58);

[0193] (59);

[0194] in, It is the erosion rate of the coolant on corrosion products. It is the coolant erosion constant. It is the coolant shear force. It is the deposition work, a constant value; It is the total adhesion energy, a constant value; It is the thickness of the previous moment.

[0195] Step 405: Determine the growth rate based on the deposition rate of soluble corrosion products, the deposition rate of insoluble corrosion products, and the erosion rate of corrosion products by the coolant.

[0196] In some embodiments, the growth rate of the oxide corrosion product deposit layer at the current moment can be obtained based on the following formula (60).

[0197] (60);

[0198] The boron migration distribution prediction method in the pressurized water reactor oxidation corrosion product deposit layer according to the present invention combines the deposition of soluble and insoluble corrosion products with the erosion effect of coolant when calculating the growth rate of the oxidation corrosion product deposit layer, making the thickness of the obtained oxidation corrosion product deposit layer more accurate, thereby improving the accuracy of boron migration distribution prediction.

[0199] To achieve the above embodiments, the present invention also provides a device for predicting the boron migration distribution within the deposited layer of pressurized water reactor oxidation corrosion products.

[0200] Figure 6 This is a schematic diagram of a device for predicting the migration and distribution of boron within a pressurized water reactor oxidation corrosion product deposit layer, provided as an embodiment of the present invention. Figure 6 As shown, the device may include an acquisition module 610, a first determination module 620, a second determination module 630, a third determination module 640, and a fourth determination module 650.

[0201] The acquisition module 610 is used to acquire the total heat flux density of the outer surface of the oxide corrosion product deposit layer.

[0202] The first determining module 620 is used to determine the outer surface temperature of the oxidative corrosion product deposit layer based on the distribution principle of the total heat flux density of the outer surface for convective heat transfer and boiling heat transfer.

[0203] The second determining module 630 is used to determine the growth rate of the oxide corrosion product deposit layer based on the external surface temperature and update the thickness of the oxide corrosion product deposit layer.

[0204] The third determining module 640 is used to determine the temperature distribution within the oxide corrosion product deposition layer based on the outer surface temperature and thickness, as well as the energy conservation equation within the oxide corrosion product deposition layer.

[0205] The fourth determining module 650 is used to obtain the boron migration distribution within the oxide corrosion product deposition layer based on the convection-diffusion reaction transport equation and temperature distribution of boron within the oxide corrosion product deposition layer.

[0206] In some embodiments, the first determining module 620 is specifically used for:

[0207] Assume an initial outer surface temperature;

[0208] Based on the initial external surface temperature, the theoretical supercooled boiling heat flux density and the theoretical convective heat flux density of the external surface of the oxide corrosion product deposition layer are determined.

[0209] Based on the external surface theory of supercooled boiling heat flux density, external surface theory of convective heat flux density, and external surface total heat flux density, the power-order coupling relationship is determined.

[0210] Based on the total heat flux density of the outer surface, the power coupling relationship, the theoretical supercooled boiling heat flux density of the outer surface, and the theoretical convective heat flux density of the outer surface, the actual supercooled boiling heat flux density and the actual convective heat flux density of the outer surface of the oxidative corrosion product deposit layer are determined respectively.

[0211] If the actual supercooled boiling heat flux density, the actual convective heat flux density, and the total heat flux density of the outer surface satisfy the power law, the initial outer surface temperature is determined as the outer surface temperature; otherwise, the initial outer surface temperature is adjusted and the power law verification is continued.

[0212] In some embodiments, the second determining module 630 is specifically used for:

[0213] Based on the external surface temperature and the growth model of the oxide corrosion product deposit layer, the growth rate of the oxide corrosion product deposit layer is determined; wherein, the growth model of the oxide corrosion product deposit layer is used to characterize the growth process of the oxide corrosion product deposit layer.

[0214] As one possible implementation, the oxidation corrosion product deposition layer growth model includes a soluble corrosion product deposition model, a sparingly soluble corrosion product deposition model, and a coolant erosion model; the soluble corrosion product deposition model is used to characterize the mass transfer process of soluble corrosion products in the coolant and the precipitation process of soluble corrosion products on the cladding surface; the sparingly soluble corrosion product deposition model is used to characterize the mass transfer process of sparingly soluble corrosion products; the second determining module is also used for:

[0215] Based on the external surface temperature, the saturation concentration of soluble corrosion products, the concentration of sparingly soluble corrosion products, the precipitation coefficient of soluble corrosion products, the mass transfer coefficient of sparingly soluble corrosion products, and the coolant shear force are determined.

[0216] Based on the deposition model of soluble corrosion products, the saturation concentration of soluble corrosion products, and the precipitation coefficient of soluble corrosion products, the deposition rate of soluble corrosion products is determined.

[0217] Based on the deposition model of sparingly soluble corrosion products, the concentration of sparingly soluble corrosion products, and the mass transfer coefficient of sparingly soluble corrosion products, the deposition rate of sparingly soluble corrosion products is determined.

[0218] Based on the coolant erosion model and coolant shear force, the erosion rate of the coolant on corrosion products is determined.

[0219] The growth rate is determined based on the deposition rate of soluble corrosion products, the deposition rate of sparingly soluble corrosion products, and the erosion rate of corrosion products by the coolant.

[0220] In some embodiments, the third determining module 640 is specifically used for:

[0221] Using the outer surface temperature and thickness as boundary conditions, the temperature distribution is determined based on the energy conservation equation within the oxide corrosion product deposition layer.

[0222] In some embodiments, the third determining module 640 is further configured to:

[0223] The first heat transfer equation is constructed for the wet zone within the oxide corrosion product deposit layer; the wet zone refers to the cylindrical region surrounding the chimney within the oxide corrosion product deposit layer.

[0224] A second heat transfer equation is constructed for the surface of the chimney within the oxide corrosion product deposit layer; both the first and second heat transfer equations are related to the temperature distribution.

[0225] Based on the first and second heat transfer equations, an energy conservation equation for the oxidative corrosion product deposition layer is constructed.

[0226] In some embodiments, the boron migration distribution includes the concentration distribution of various boron-containing solutes within the oxide corrosion product deposition layer; the fourth determining module 650 is specifically used for:

[0227] For each boron-containing solute, based on the temperature distribution and at least one chemical reaction in which the boron-containing solute participates, the theoretical concentration distribution of the boron-containing solute after chemical reaction equilibrium is determined for each chemical reaction.

[0228] Based on the theoretical concentration distribution of boron-containing solutes for each chemical reaction and the convection-diffusion reaction transport equation, the concentration distribution of boron-containing solutes in the oxidative corrosion product deposition layer is determined.

[0229] It should be noted that the explanations and descriptions in the above embodiments regarding the method for predicting the boron migration and distribution in the pressurized water reactor oxidation corrosion product deposit layer can also be applied to the device for predicting the boron migration and distribution in the pressurized water reactor oxidation corrosion product deposit layer in the embodiments of the present invention, and will not be repeated here.

[0230] Figure 7 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 7 As shown, the electronic device may include a processor 710, a communication interface 720, a memory 730, and a communication bus 740, wherein the processor 710, the communication interface 720, and the memory 730 communicate with each other via the communication bus 740. The processor 710 can call the computer program in the memory 730 to execute the steps of the boron migration and distribution prediction method in the pressurized water reactor oxidation corrosion product deposit layer provided in the above embodiment.

[0231] For example, the method includes: obtaining the total heat flux density of the outer surface of the oxide corrosion product deposit layer; determining the outer surface temperature of the oxide corrosion product deposit layer based on the distribution principle of the total heat flux density of the outer surface for convective heat transfer and boiling heat transfer; determining the growth rate of the oxide corrosion product deposit layer based on the outer surface temperature and updating the thickness of the oxide corrosion product deposit layer; determining the temperature distribution within the oxide corrosion product deposit layer according to the outer surface temperature and thickness, as well as the energy conservation equation within the oxide corrosion product deposit layer; and obtaining the boron migration distribution within the oxide corrosion product deposit layer based on the convective-diffusion reaction transport equation and temperature distribution regarding boron within the oxide corrosion product deposit layer.

[0232] Furthermore, the logical instructions in the aforementioned memory 730 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0233] On the other hand, embodiments of the present invention also provide a computer program product, the computer program product including a computer program that can be stored on a computer-readable storage medium, and when the computer program is executed by a processor, the computer is able to perform the steps of the method for predicting the boron migration distribution in the pressurized water reactor oxidation corrosion product deposit layer provided in the above embodiments.

[0234] On the other hand, embodiments of the present invention also provide a non-transitory computer-readable storage medium storing a computer program thereon, the computer program being used to cause a processor to execute the method for predicting the boron migration distribution within the pressurized water reactor oxidation corrosion product deposit layer provided in the above embodiments.

[0235] The non-transitory computer-readable storage medium can be any available medium or data storage device that the processor can access, including but not limited to magnetic memory (e.g., floppy disk, hard disk, magnetic tape, magneto-optical disk (MO)), optical memory (e.g., CD, DVD, BD, HVD), and semiconductor memory (e.g., ROM, EPROM, EEPROM, non-volatile memory (NAND FLASH), solid-state drive (SSD)).

[0236] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0237] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0238] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for predicting the boron migration and distribution within the deposited layer of oxidation corrosion products in a pressurized water reactor, characterized in that, include: Obtain the total heat flux density of the outer surface of the oxide corrosion product deposit layer; Based on the principle of the distribution of the total heat flux density of the outer surface to convective heat transfer and boiling heat transfer, the outer surface temperature of the oxidative corrosion product deposition layer is determined. Based on the external surface temperature, the growth rate of the oxide corrosion product deposit layer is determined, and the thickness of the oxide corrosion product deposit layer is updated. The temperature distribution within the oxidation corrosion product deposition layer is determined based on the outer surface temperature, the thickness, and the energy conservation equation within the deposition layer. Based on the convection-diffusion transport equation for boron within the oxide corrosion product deposit layer and the temperature distribution, the boron migration distribution within the oxide corrosion product deposit layer is obtained.

2. The method according to claim 1, characterized in that, The allocation principle satisfies a power law; the determination of the outer surface temperature of the oxidative corrosion product deposit layer based on the allocation principle of the total heat flux density of the outer surface for convective heat transfer and boiling heat transfer includes: Assume an initial outer surface temperature; Based on the initial outer surface temperature, the theoretical supercooled boiling heat flux density and the theoretical convective heat flux density of the outer surface of the oxide corrosion product deposition layer are determined. Based on the theoretical supercooled boiling heat flux density of the outer surface, the theoretical convective heat flux density of the outer surface, and the total heat flux density of the outer surface, the power-order coupling relationship is determined. Based on the total heat flux density of the outer surface, the power coupling relationship, the theoretical supercooled boiling heat flux density of the outer surface, and the theoretical convective heat flux density of the outer surface, the actual supercooled boiling heat flux density and the actual convective heat flux density of the outer surface of the oxidative corrosion product deposition layer are determined respectively. If the actual supercooled boiling heat flux density, the actual convective heat flux density, and the total heat flux density of the outer surface satisfy a power law, the initial outer surface temperature is determined as the outer surface temperature; otherwise, the initial outer surface temperature is adjusted to continue the power law verification.

3. The method according to claim 1, characterized in that, Determining the growth rate of the oxidation corrosion product deposit layer based on the outer surface temperature includes: The growth rate is determined based on the external surface temperature and the growth model of the oxide corrosion product deposit layer; wherein, the growth model of the oxide corrosion product deposit layer is used to characterize the growth process of the oxide corrosion product deposit layer.

4. The method according to claim 3, characterized in that, The oxidation corrosion product deposition layer growth model includes a soluble corrosion product deposition model, a sparingly soluble corrosion product deposition model, and a coolant erosion model. The soluble corrosion product deposition model characterizes the mass transfer process of soluble corrosion products in the coolant and the precipitation process of the soluble corrosion products on the cladding surface. The sparingly soluble corrosion product deposition model characterizes the mass transfer process of the sparingly soluble corrosion products. The coolant erosion model characterizes the erosion effect of the coolant on the deposits. Determining the growth rate based on the outer surface temperature and the oxidation corrosion product deposition layer growth model includes: Based on the external surface temperature, the saturation concentration of soluble corrosion products, the concentration of sparingly soluble corrosion products, the precipitation coefficient of soluble corrosion products, the mass transfer coefficient of sparingly soluble corrosion products, and the coolant shear force are determined. Based on the soluble corrosion product deposition model, the saturation concentration of the soluble corrosion product, and the precipitation coefficient of the soluble corrosion product, the deposition rate of the soluble corrosion product is determined. Based on the deposition model of the sparingly soluble corrosion products, the concentration of the sparingly soluble corrosion products, and the mass transfer coefficient of the sparingly soluble corrosion products, the deposition rate of the sparingly soluble corrosion products is determined. Based on the coolant erosion model and the coolant shear force, the erosion rate of the coolant on the corrosion products is determined. The growth rate is determined based on the deposition rate of the soluble corrosion products, the deposition rate of the sparingly soluble corrosion products, and the erosion rate of the corrosion products by the coolant.

5. The method according to claim 1, characterized in that, The step of determining the temperature distribution within the oxidation corrosion product deposition layer based on the outer surface temperature, the thickness, and the energy conservation equation within the oxidation corrosion product deposition layer includes: Using the outer surface temperature and the thickness as boundary conditions, the temperature distribution is determined based on the energy conservation equation within the oxide corrosion product deposition layer.

6. The method according to claim 1, characterized in that, The energy conservation equation within the oxidative corrosion product deposit layer was pre-constructed in the following manner: A first heat transfer equation is constructed for the wet region within the oxide corrosion product deposit layer; the wet region refers to the cylindrical region surrounding the chimney within the oxide corrosion product deposit layer. A second heat transfer equation is constructed for the surface of the chimney within the oxide corrosion product deposition layer; both the first heat transfer equation and the second heat transfer equation are related to the temperature distribution. Based on the first heat transfer equation and the second heat transfer equation, an energy conservation equation for the oxidative corrosion product deposition layer is constructed.

7. The method according to claim 1, characterized in that, The boron migration distribution includes the concentration distribution of various boron-containing solutes within the oxidative corrosion product deposition layer; obtaining the boron migration distribution within the oxidative corrosion product deposition layer based on the convection-diffusion reaction transport equation for boron within the oxidative corrosion product deposition layer and the temperature distribution includes: For each boron-containing solute, based on the temperature distribution and at least one chemical reaction in which the boron-containing solute participates, the theoretical concentration distribution of the boron-containing solute after chemical reaction equilibrium is determined for each chemical reaction. Based on the theoretical concentration distribution of the boron-containing solute for each of the chemical reactions and the convection-diffusion reaction transport equation, the concentration distribution of the boron-containing solute within the oxidative corrosion product deposition layer is determined.

8. A device for predicting boron migration and distribution in pressurized water reactor oxidation corrosion product deposits, characterized in that, include: The acquisition module is used to acquire the total heat flux density of the outer surface of the oxide corrosion product deposit layer; The first determining module is used to determine the outer surface temperature of the oxidative corrosion product deposit layer based on the distribution principle of the total heat flux density of the outer surface for convective heat transfer and boiling heat transfer. The second determining module is used to determine the growth rate of the oxidation corrosion product deposition layer based on the outer surface temperature, and to update the thickness of the oxidation corrosion product deposition layer. The third determining module is used to determine the temperature distribution within the oxidation corrosion product deposition layer based on the outer surface temperature and the thickness, as well as the energy conservation equation within the oxidation corrosion product deposition layer. The fourth determining module is used to obtain the boron migration distribution within the oxide corrosion product deposition layer based on the convection-diffusion reaction transport equation for boron within the oxide corrosion product deposition layer and the temperature distribution.

9. An electronic device, characterized in that, The device includes a processor and a memory storing a computer program, wherein the processor executes the program to implement the method for predicting the boron migration distribution within the pressurized water reactor oxidation corrosion product deposit layer as described in any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method for predicting the boron migration distribution within the pressurized water reactor oxidation corrosion product deposit layer as described in any one of claims 1 to 7.

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