Pressurized water reactor core oxidation corrosion product deposition multi-physical coupling hardware-in-loop device

Abstract

A pressurized water reactor core oxidation corrosion product deposition multi-physical coupling hardware-in-loop device comprises a corrosion product accelerated deposition system, an element online testing system and an axial power offset digital mirror image system. According to the method, the complex multi-physics field coupling process of hydrochemistry, material corrosion, flow heat transfer, neutron physics and the like involved in oxidation corrosion product deposition can be achieved, off-line data transmission between single physics fields is avoided, the growth rule of a deposition layer is directly obtained, the deposition mechanism of oxidation corrosion products is analyzed, and the deposition efficiency is improved. The defects that an existing device cannot perform entity verification and cannot obtain element concentration and distribution in a corrosion product deposition layer are overcome.

Description

Technical Field

[0001] This invention relates to a technology in the field of reactor control, specifically a hardware-in-the-loop device for multi-physics coupling of pressurized water reactor core oxidation corrosion product deposition. Background Technology

[0002] Due to the high temperature, high pressure, and high radioactivity within nuclear reactors, it is impossible to directly analyze the multi-physics coupling processes involved in the deposition of core oxidation and corrosion products, or the deposition mechanism of these products, through in-reactor measurements. Currently, the most representative research method is offline characterization, which involves extracting fuel assemblies from the reactor core for external cooling and oxidation, cutting the cladding, and preparing samples of the oxidation and corrosion product deposition layer for microscopic characterization by electron microscopy (SEM) and elemental analysis by energy dispersive spectroscopy (EDS). Based on this, the deposition mechanism of oxidation and corrosion products on the cladding, and the influence of oxidation and corrosion product deposition on cladding heat transfer and elemental distribution, can be deduced through data transfer between individual physical fields. However, the aforementioned data transfer method between individual physical fields cannot realize the multi-physics coupling processes involved in the deposition of oxidation and corrosion products. Furthermore, since the solubility of the materials constituting the oxide corrosion product deposition layer (such as NiO, NiFe2O4 and Li2B4O7) is closely related to temperature, the deposition layer materials may dissolve or precipitate again during the preparation of oxide corrosion product deposition layer samples, leading to deviations in the measurement of oxide corrosion product deposition and element migration behavior. Therefore, it is impossible to accurately analyze the deposition mechanism of oxide corrosion products in the reactor core. Summary of the Invention

[0003] To address the aforementioned shortcomings of existing technologies, this invention proposes a hardware-in-the-loop device for multi-physics coupling in the deposition of oxidation and corrosion products in pressurized water reactor cores. This device can realize the complex process of multi-physics coupling involved in the deposition of oxidation and corrosion products, including water chemistry, material corrosion, flow heat transfer, and neutron physics. It avoids offline data transmission between individual physical fields, directly obtains the growth law of the deposition layer, and analyzes the deposition mechanism of oxidation and corrosion products. This invention overcomes the shortcomings of existing devices that cannot be physically verified and cannot obtain the elemental concentration and distribution inside the corrosion product deposition layer.

[0004] This invention is achieved through the following technical solution:

[0005] The present application relates to a kind of pressurized water reactor core oxidation corrosion product deposition multi-physics coupling hardware-in-the-loop device, comprising: corrosion product accelerated deposition system, element online testing system and axial power offset digital mirror system, wherein: corrosion product accelerated deposition system is according to the rapid deposition of precursor on cladding, obtains oxidation corrosion product deposition layer;Element online testing system is by prompt gamma activation technology, online analysis oxidation corrosion product deposition layer Growth rule and the element distribution in deposition layer;Axial power offset digital mirror system is according to the element distribution of deposition layer Calculation section information of neutron flux, and then calculate the axial power distribution, control heating unit cladding surface heat transfer boundary, realize oxidation corrosion product deposition-element migration distribution-axial power offset coupling.

[0006] The present application relates to a kind of control method based on the above system, comprising:

[0007] Step one, accelerated deposition precursor preparation, specifically comprising:

[0008] 1.1 by simulating the upper and lower loop of the reactor coolant loop and the containment system, according to Gibbs free energy change under typical pressurized water reactor conditions, determine the thermodynamic equilibrium constant of each reaction in high-transmission solution, so as to obtain the concentration of Li-B-D2O system and pH value, specifically: Gibbs free energy change in high-transmission solution is obtained by formula Determination, wherein: The corrected Gibbs free energy of formation of the reactants at high temperature and high pressure Difference.

[0009] 1.2 control the temperature of coolant, and regulate the concentration of boron, lithium and oxidation corrosion product in loop, determine Fe, Ni stable phase distribution by Gibbs free energy minimization of multicomponent solute-solvent system chemical equilibrium, so as to adjust the ratio of soluble Fe, Ni and suspended particles, form oxidation corrosion product precursor, specifically: by simultaneously solving the equilibrium equation of each reaction, element mass conservation equation and charge conservation equation, the concentration of each component at system equilibrium is obtained by Newton-Raphson iteration calculation.

[0010] 1.3 accelerated deposition of corrosion products: according to the parameters obtained in step 1.2, the obtained precursor is added to the coolant loop, and the oxidation corrosion product deposition layer is formed on the cladding by accelerated deposition.

[0011] Step two, using neutron beam to irradiate the oxidation corrosion product deposition layer obtained in step one, calculate the three-dimensional distribution of Fe, Ni and B according to the prompt gamma rays of different energy released by different elements and neutron nuclear reaction, specifically including:

[0012] 2.1 Use total reflection neutron lens to simulate the convergence behavior of rays by Monte Carlo method, calculate the optimal convergence and gain conditions. Use the optimal convergence gain to irradiate the oxidation corrosion product deposition layer obtained in step one with cold neutron beam, and induce prompt gamma activation.

[0013] 2.2 Use high-purity germanium detector to receive activated gamma rays and obtain the activated gamma spectrum of oxidation corrosion products, calculate the content information of each element in the oxidation corrosion product deposition layer by identifying the characteristic peaks of each element and combining the background.

[0014] 2.3 Use Compton camera to receive activated gamma rays, make gamma rays undergo Compton scattering inside, and analyze and calculate the obtained Compton scattering information to output the location of gamma activation in the oxidation corrosion product deposition layer and the spatial distribution information of each element in the oxidation corrosion product deposition layer.

[0015] Step three, according to the spatial distribution information of each element, use data-driven proper orthogonal decomposition (POD) reduction algorithm to obtain the three-dimensional axial power distribution of the fuel rod, and then realize feedback control of the cladding surface heat flux, thereby actively adjusting the deposition of corrosion products and the migration distribution of elements, which specifically includes:

[0016] 3.1 According to the spatial distribution information of each element, use the background grid mixed layer cross section homogenization method to construct a multi-dimensional multi-group neutron cross section database.

[0017] 3.2 On the basis of the background grid method, according to the multi-dimensional multi-group neutron cross section database obtained by the variational principle and the background grid mixed layer cross section homogenization method, obtain full-order matrix equations respectively representing the neutron balance relationship inside the finite element block and the neutron continuity relationship on the surface of the block.

[0018] 3.3 Use data-driven proper orthogonal decomposition reduction algorithm to construct a reduced-order model for neutron transport simulation and solve the reduced-order basis. Use linear interpolation, Gaussian process regression, decision tree, neural network and other methods to obtain the prediction model between parameters and coefficients. Using the reduced-order basis obtained by the reduced-order algorithm and the prediction model trained, the full-order matrix obtained in step 3.2 can be reduced and accelerated to solve, and then the three-dimensional power distribution of the fuel rod under different oxidation corrosion product deposition layer thicknesses can be quickly predicted.

[0019] 3.4 Based on the power distribution information predicted in step 3.3, set the power source and adjust the heating power to realize feedback control, and then adjust the deposition of oxidation corrosion products and the migration distribution of elements in real time.

[0020] Technical effects

[0021] The present application adopts the analysis system of multi-physical coupling processes of water chemistry-material corrosion-flow heat transfer-neutron physics and the multi-physical coupling hardware-in-the-loop device of oxidation corrosion product deposition, realizes the multi-physical coupling processes of water chemistry-material corrosion-flow heat transfer-neutron physics involved in oxidation corrosion product deposition, so as to analyze the growth rule of oxidation corrosion product deposition layer and the deposition mechanism of oxidation corrosion product; the on-line measurement of oxidation corrosion product deposition can be realized, and the measurement error caused by the property change of the deposition layer due to the change of the environment (temperature, pressure, etc.) during off-line measurement can be avoided. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a system schematic diagram of the present application;

[0023] Figure 2 It is a corrosion product accelerated deposition system schematic diagram;

[0024] In the figure: neutron spectrometer 1, preheater 2, centrifugal pump 3, heat exchanger 4, pressure stabilizer 5, control and collection system 6, plate heat exchanger 7, injection pump 8, water chemistry instrument box 9, precursor 10, boron-containing water 11, lithium-containing water 12, pressure gauge 13, pressure relief valve 14, flow meter 15;

[0025] Figure 3 It is an element on-line test system schematic diagram;

[0026] Figure 4 It is a neutron algorithm reduced-order model and heating unit schematic diagram. DETAILED DESCRIPTION

[0027] As shown in Figure 1 , it is a pressurized water reactor core oxidation corrosion product deposition multi-physical coupling hardware-in-the-loop device involved in the present embodiment, which comprises: a corrosion product accelerated deposition system for reproducing the water chemistry and flow heat transfer environment in a typical pressurized water reactor primary loop system, providing a scene for oxidation corrosion product deposition on the cladding surface, an element on-line test system for measuring the element distribution information in the oxidation corrosion product deposition layer in real time, and an axial power offset digital mirror system for realizing the coupling of corrosion product deposition-element migration distribution-axial power offset.

[0028] As shown in Figure 2As shown, the corrosion product accelerated deposition system comprises a control and collection system 6, a neutron spectrometer 1, a preheater 2, a centrifugal pump 3, a heat exchanger 4, a pressure stabilizer 5 arranged between the neutron spectrometer 1 and the heat exchanger 4, an injection pump 8 arranged between the centrifugal pump 3 and the heat exchanger 4, a water chemical instrument box 9, a pressure relief valve 14 and a plate heat exchanger 7, wherein: a precursor 10, boron-containing water 11 and lithium-containing water 12 are arranged between the injection pump 8 and the water chemical instrument box 9 in sequence, the control and collection system 6 is connected with valves, pumps, measuring instruments and other devices of the entire system, collects information such as temperature, flow rate, pressure and chemical indicators of the loop, and performs real-time monitoring of loop information and terminal control of loop devices.

[0029] The neutron spectrometer 1, the preheater 2, the centrifugal pump 3, the heat exchanger 4 and the pressure stabilizer 5 constitute an analog reactor coolant loop; the plate heat exchanger 7, the injection pump 8, the water chemical instrument box 9, the precursor 10, the boron-containing water 11, the lithium-containing water 12 constitute an upper charging and lower discharging loop of the chemical control system, control the temperature of the coolant, and regulate the concentration of boron, lithium and oxidized corrosion products in the loop.

[0030] Due to the strict water chemical control of the pressurized water reactor, the deposition of oxidized corrosion products on the surface of the fuel cladding is a long solute migration process. Due to the dependence of the online test technology of prompt gamma activation on the experimental reactor resources, the matching element online test system needs to accelerate the deposition of oxidized corrosion products.

[0031] The accelerated deposition refers to: Fe and Ni suspended particles are prepared by using ammonium iron sulfate dodecahydrate, tetramethylammonium hydroxide and nickel chloride hexahydrate, and soluble Fe and Ni are synthesized by using ethylenediaminetetraacetic acid, ammonia water, ultra-fine Fe powder and nickel hydroxide. Heavy water is used as a solvent for dissolving oxidized corrosion products (high-transmission neutron solvent) to reduce the interference with the neutron beam and realize online measurement of elements. The Helgeson-Kirkham-Flowers equation is used to obtain the Gibbs free energy of multiple components in heavy water under high temperature and high pressure, so as to determine the reaction equilibrium constant. The stable phase distribution of Fe and Ni is determined through the chemical equilibrium of the Gibbs free energy minimization of the multi-component solute-solvent system, so as to adjust the ratio of soluble Fe and Ni to suspended particles, dissolve the soluble Fe and Ni meeting the target ratio into the heavy water solvent, and then add chemical reagents containing B, Li and other elements to complete the preparation of the high-concentration and high-transmission oxidized corrosion product deposition precursor.

[0032] The Helgeson-Kirkham-Flowers equation is as follows: wherein: is the correction value of the Gibbs generation free energy under the target temperature T (K) and the target pressure P (bar), and The reference temperature and the reference pressure are respectively 298.15 K and 1 bar, The Gibbs free energy of formation at the reference temperature and the reference pressure, The absolute entropy value at the reference temperature and the reference pressure, The solvent pressure parameter is 2600 bar; The solvent temperature parameter is 228 K. , , And The volume integral constant; And The specific heat integral constant; The Born constant; The dielectric constant of water; The Born function, usually .

[0033] As shown in Figure 3 The element online testing system comprises a neutron beam flow converging unit and a prompt gamma activation testing unit, wherein the neutron beam flow converging unit converges cold neutron beam flow led out by a research reactor to obtain cold neutron beam flow with gain and irradiate the cold neutron beam flow to an oxidation corrosion product deposition layer; the prompt gamma activation testing unit detects prompt gamma rays generated by the interaction of cold neutrons and the deposition layer to obtain the axial Fe, Ni and B element concentration distribution of the deposition layer and calculate the thickness of the deposition layer.

[0034] The neutron beam flow converging unit of the element online testing system adopts an ellipsoidal total reflection neutron lens to enhance the intensity of the neutron beam flow, realize the focusing of the neutron beam flow and the gain of the neutron flux density. In order to expand the angle range of the captured neutrons, a concentric multi-stage ellipsoid nesting system is adopted, a plurality of large ellipsoids with the same focal point are superimposed on the periphery of the original small ellipsoid to realize the grading and screening, so that better converging gain effect is realized.

[0035] The prompt gamma activation testing unit of the element online testing system utilizes the prompt gamma activation technology to characterize the Fe, Ni and B elements in the oxidation corrosion product deposition layer. The content of Fe, Ni and B is determined by measuring the intensity of the characteristic gamma rays, and the thickness of the oxidation corrosion product deposition layer is determined by the total amount of Fe and Ni elements, so as to analyze the deposition mechanism of the oxidation corrosion product. By detecting the intensity of the characteristic gamma rays and 10 The content of the boron element can be determined by the abundance of B, so as to provide reference data for the neutron cross section database calculation of the power distribution unit in the axial power offset digital mirror system.

[0036] As shown in Figure 4The axial power offset digital mirror system comprises a power distribution unit and a heating unit, wherein: the power distribution unit obtains three-dimensional axial power distribution information of the fuel rod by high-resolution neutron algorithm combined with deposition layer element distribution as cross-section input information of neutron flux; and the heating unit controls the cladding surface heat flow in real time according to the power distribution information calculated by the digital mirror system.

[0037] The power distribution unit constructs a multi-dimensional multi-group neutron cross-section database by using a background grid mixed layer cross-section homogenization method based on the deposition layer element distribution of the oxidation corrosion product obtained by the prompt gamma activation analysis. By introducing the simplification of mixed materials, the axial cells of the deposition layer with different thicknesses are described by using the same set of finite element grids, the physical parameters between the axial grids are directly mapped, the quality of the finite element grid is improved without the need for circumferential encryption, and the precision loss of high-fidelity simulation caused by the complete homogenization of the deposition layer and the background material is avoided. On the basis of the background grid method, the full-order matrix equation representing the neutron balance relationship inside the finite element block and the neutron continuity relationship on the block surface is obtained according to the variational principle. A data-driven proper orthogonal decomposition (POD) reduction algorithm is used to construct a reduced-order model of neutron transport simulation in a certain parameter space. On this basis, the prediction model between the parameters and the coefficients is obtained by using linear interpolation, Gaussian process regression, decision tree, neural network and other methods. The trained prediction model and the reduced-order basis are used to accelerate the above full-order model, and the three-dimensional power distribution of the fuel rod under different oxidation corrosion product deposition layer thicknesses is quickly predicted.

[0038] The full-order matrix equation is specifically: , , , , , is a response matrix.

[0039] The heating unit adopts a distributed heating ring with a spatial resolution of 10 mm to real-time regulate the axial heat flux density. A special Bragg (FBG) optical fiber made of an ultraviolet writing grating and a polyimide coating layer is used to realize quasi-three-dimensional measurement of the cladding temperature, and the cladding surface temperature boundary under the axial power offset is accurately obtained. Based on the element distribution obtained by the prompt gamma activation technology, combined with the axial power distribution of the power distribution unit, the independent dynamic control of the axial power of the heating unit is realized, and according to the cladding wall temperature and the oxidation corrosion product deposition layer thickness information, the mechanism analysis of the oxidation corrosion product deposition in the pressurized water reactor core is realized.

[0040] Compared with the prior art, the device can realize online measurement and characterization of the oxidation corrosion product deposition layer, obtain the content and distribution of elements in the deposition layer, and further study the mechanism of oxidation corrosion product deposition; through the digital mirror system, the device can calculate the axial power offset in real time and quickly feedback to the physical heating element, so as to timely and accurately regulate the heat flux density of the cladding surface.

[0041] The above specific embodiments can be adjusted in different ways by those skilled in the art without departing from the principles and purposes of the present application, the protection scope of the present application is subject to the claims and is not limited by the above specific embodiments, and each implementation scheme within the scope is subject to the present application.

Claims

1. A hardware-in-the-loop device for multi-physics coupling of oxidation corrosion product deposition in a pressurized water reactor core, characterized in that, include: The system comprises an accelerated deposition system for corrosion products, an online elemental analysis system, and an axial power offset digital mirroring system. The accelerated deposition system rapidly deposits precursors onto a cladding layer to obtain an oxidative corrosion product deposition layer. The online elemental analysis system uses transient gamma activation technology to analyze the growth pattern and elemental distribution within the deposition layer. The axial power offset digital mirroring system calculates the neutron flux cross-sectional information based on the elemental distribution of the deposition layer, calculates the axial power distribution, controls the heat transfer boundary on the cladding surface of the heating unit, and achieves the coupling of oxidative corrosion product deposition, elemental migration and distribution, and axial power offset.

2. The multi-physics coupled hardware-in-the-loop device for depositing oxidation and corrosion products in a pressurized water reactor core according to claim 1, characterized in that, The corrosion product accelerated deposition system includes: a control and acquisition system, a neutron spectrometer connected in sequence to form a loop, a preheater, a centrifugal pump, a heat exchanger, a voltage regulator located between the neutron spectrometer and the heat exchanger, an injection pump located between the centrifugal pump and the heat exchanger, a water chemistry instrument box, a pressure relief valve, and a plate heat exchanger. The precursor, boron-containing water, and lithium-containing water are sequentially located between the injection pump and the water chemistry instrument box. The control and acquisition system is connected to the valves, pumps, measuring instruments, and other devices of the entire system to acquire information such as loop temperature, flow rate, pressure, and chemical parameters, enabling real-time monitoring of loop information and terminal control of loop devices.

3. The multi-physics coupled hardware-in-the-loop device for depositing oxidation and corrosion products in a pressurized water reactor core according to claim 2, characterized in that, The neutron spectrometer, preheater, centrifugal pump, heat exchanger, and pressure regulator constitute the coolant loop of the simulated reactor; the plate heat exchanger, injection pump, water chemistry instrument box, precursor, boron-containing water, and lithium-containing water constitute the charging and discharging loop of the chemical capacity system, which controls the temperature of the coolant and regulates the concentration of boron, lithium, and oxidation corrosion products in the loop.

4. The multi-physics coupled hardware-in-the-loop device for depositing oxidation and corrosion products in a pressurized water reactor core according to claim 1 or 2, characterized in that, The accelerated deposition process involves preparing Fe and Ni suspended particles using ferric ammonium sulfate dodecahydrate, tetramethylammonium hydroxide, and nickel chloride hexahydrate; synthesizing soluble Fe and Ni using ethylenediaminetetraacetic acid, ammonia, ultrafine Fe powder, and nickel hydroxide; using heavy water as a high-permeability neutron solvent to dissolve the oxidation corrosion products, reducing interference with the neutron beam and enabling online elemental measurement; using the Helgeson-Kirkham-Flowers equation to obtain the Gibbs free energy of multiple components in heavy water under high temperature and pressure, thereby determining the reaction equilibrium constant; determining the stable phase distribution of Fe and Ni through the chemical equilibrium of minimizing the Gibbs free energy of the multi-component solute-solvent system; adjusting the ratio of soluble Fe and Ni to the suspended particles; dissolving soluble Fe and Ni in the heavy water solvent to the target ratio; and then adding chemical reagents containing elements such as B and Li to complete the preparation of a high-concentration, high-permeability oxidation corrosion product deposition precursor. The Helgeson-Kirkham-Flowers equations are as follows: ,in: This is a correction value for the Gibbs free energy of formation at the target temperature T (K) and target pressure P (bar). and For reference temperature and reference pressure, To provide the Gibbs free energy of formation at the reference temperature and pressure, For reference temperature and pressure, the absolute entropy value, Solvent pressure parameters Solvent temperature parameters , , and Volume integral constant; and Specific heat integral constant; Born constant; Dielectric constant of water; Born function .

5. The multi-physics coupled hardware-in-the-loop device for depositing oxidation and corrosion products in a pressurized water reactor core according to claim 1, characterized in that, The aforementioned online elemental testing system includes: a neutron beam focusing unit and a transient gamma activation testing unit, wherein: the neutron beam focusing unit focuses the cold neutron beam extracted from the research reactor to obtain an amplified cold neutron beam, and irradiates it onto the oxide corrosion product deposition layer; the transient gamma activation testing unit detects the transient gamma rays generated by the interaction between the cold neutrons and the deposition layer, obtains the axial elemental concentration distribution of Fe, Ni, and B in the deposition layer, and estimates the thickness of the deposition layer.

6. The multi-physics coupled hardware-in-the-loop device for depositing oxidation and corrosion products in a pressurized water reactor core according to claim 5, characterized in that, The neutron beam focusing unit employs an ellipsoidal total reflection neutron lens and a concentric multi-level ellipsoid nesting system to enhance the neutron beam intensity. By superimposing multiple large ellipsoids with the same focus around the original small ellipsoid, hierarchical screening is achieved, thereby realizing a better focusing gain effect.

7. The multi-physics coupled hardware-in-the-loop device for depositing oxidation and corrosion products in a pressurized water reactor core according to claim 5, characterized in that, The aforementioned instantaneous gamma activation testing unit determines the contents of Fe, Ni, and B by measuring the intensity of characteristic gamma rays, and determines the thickness of the oxide corrosion product deposition layer by measuring the total amount of Fe and Ni elements, thereby analyzing the deposition mechanism of the oxide corrosion products; by detecting the intensity of characteristic gamma rays and 10 The abundance of B can determine the boron content, thus providing reference data for neutron cross-section database calculations in the power distribution unit of the axial power offset digital mirror system.

8. The multi-physics coupled hardware-in-the-loop device for depositing oxidation and corrosion products in a pressurized water reactor core according to claim 1, characterized in that, The axial power offset digital mirror system includes a power distribution unit and a heating unit. The power distribution unit obtains the three-dimensional axial power distribution information of the fuel rod by using a high-resolution neutron algorithm and combining the elemental distribution of the deposition layer as the cross-sectional input information of the neutron flux. The heating unit controls the heat flow on the cladding surface in real time based on the power distribution information calculated by the digital mirror system.

9. The multi-physics coupled hardware-in-the-loop device for depositing oxidation and corrosion products in a pressurized water reactor core according to claim 8, characterized in that, The power distribution unit is based on the elemental distribution of the oxidative corrosion product deposit layer obtained by transient gamma activation analysis, and a multi-dimensional multi-group neutron cross-section database is constructed by using the background grid mixing layer cross-section homogenization method. By introducing the simplification of hybrid materials, the same finite element mesh is used to describe axial grid elements of different thickness deposit layers, directly mapping the physical parameters between axial grids. This improves the quality of the finite element mesh without the need for circumferential refinement, while avoiding the accuracy loss in high-fidelity simulation caused by the complete homogenization of the deposit layer and background material. Based on the background mesh method, and according to the variational principle, full-order matrix equations representing the neutron balance relationship inside the finite element block and the neutron continuity relationship on the block surface are obtained. A data-driven intrinsic orthogonal decomposition (POD) reduction algorithm is used to construct a reduced-order model for neutron transport simulation within a certain parameter space. Based on this, linear interpolation, Gaussian process regression, decision trees, neural networks, and other methods are used to obtain a predictive model between parameters and coefficients. The trained predictive model and the reduced-order basis are used to accelerate the above full-order model, enabling rapid prediction of the three-dimensional power distribution of fuel rods under different oxide corrosion product deposit layer thicknesses. The full-order matrix equation is specifically as follows: ,in: , , , , This is the response matrix.

10. A control method based on the device according to any one of claims 1-9, characterized in that, include: Step 1: Accelerate the preparation of deposition precursors, specifically including: 1.1 By simulating the reactor coolant loop and the charging and discharging loop of the chemical and volumetric system, and based on the Gibbs free energy change under typical pressurized water reactor conditions, the thermochemical equilibrium constants of each reaction in the high-permeability solution are determined, thereby obtaining the substance concentration and pH value in the Li-B-D2O system. Specifically, the Gibbs free energy change in the high-permeability solution is given by the formula... Confirmed, among which: Gibbs free energy of formation after modification of reactants under high temperature and high pressure Obtained by subtraction; 1.2 Control the temperature of the coolant and regulate the concentrations of boron, lithium, and oxidation corrosion products in the circuit. Determine the stable phase distribution of Fe and Ni through the chemical equilibrium of minimizing the Gibbs free energy of the multi-component solute-solvent system. This allows for the adjustment of the ratio of soluble Fe, Ni, and suspended particles to form precursors for oxidation corrosion products. Specifically, the concentrations of each component at equilibrium are obtained by solving the equilibrium equations, element mass conservation equations, and charge conservation equations of each reaction simultaneously using Newton-Raphson iterative calculations. 1.3 Accelerated deposition of corrosion products: According to the parameters obtained in step 1.2, the prepared precursor is added to the coolant circuit to accelerate deposition on the cladding and form an oxide corrosion product deposition layer. Step 2: Irradiate the oxide corrosion product deposit layer obtained in Step 1 with a neutron beam. Based on the different energies of transient gamma rays released by the nuclear reactions of different elements with neutrons, calculate the three-dimensional distribution of Fe, Ni, and B. Specifically, this includes: 2.1 Using a total internal reflection neutron lens, the focusing behavior of the rays was simulated by the Monte Carlo method, and the optimal focusing and gain conditions were calculated. The oxide corrosion product deposit layer obtained in step one was irradiated with a cold neutron beam after the optimal focusing gain, resulting in transient gamma activation. 2.2 A high-purity germanium detector was used to receive activated gamma rays and obtain the activated gamma spectrum of the oxidation corrosion products. By identifying the characteristic peaks of each element and combining them with the background, the content information of each element in the deposition layer of oxidation corrosion products was calculated. 2.3 Use a Compton camera to receive activated gamma rays, causing Compton scattering of the gamma rays within the gamma rays. Analyze and calculate the obtained Compton scattering information to output the location of gamma activation within the oxide corrosion product deposit layer and the spatial distribution information of each element within the oxide corrosion product deposit layer. Step 3: Based on the spatial distribution information of each element, a data-driven intrinsic orthogonal decomposition (POD) order reduction algorithm is used to obtain the three-dimensional axial power distribution of the fuel rod, thereby achieving feedback control of the heat flux on the cladding surface and actively adjusting the deposition of corrosion products and the migration distribution of elements. include: 3.1 Based on the spatial distribution information of each element, a multi-dimensional multi-group neutron cross-section database is constructed using the background grid mixing layer cross-section homogenization method; 3.2 Based on the background mesh method, and using the multi-dimensional multi-group neutron cross-section database obtained by the variational principle and the background mesh mixed layer cross-section homogenization method, full-order matrix equations representing the neutron equilibrium relationship inside the finite element block and the neutron continuity relationship on the block surface are obtained respectively. 3.3 A data-driven intrinsic orthogonal decomposition reduction algorithm is adopted to construct a reduced-order model for neutron transport simulation, and the reduced-order basis is obtained. Using methods such as linear interpolation, Gaussian process regression, decision tree, and neural network, a prediction model between parameters and coefficients is obtained. The reduced-order basis obtained by the reduction algorithm and the prediction model obtained by training are used to accelerate the reduction of the full-order matrix obtained in step 3.2, thereby realizing the rapid prediction of the three-dimensional power distribution of fuel rods under different oxide corrosion product deposition layer thicknesses. 3.4 Based on the power distribution information predicted in step 3.3, the power supply is set and the heating power is adjusted to achieve feedback control, thereby adjusting the deposition of oxidation corrosion products and the migration distribution of elements in real time.

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