Radioactive aerosol diffusion swimming movement determination method and device and storage medium

Abstract

The invention relates to a radioactive aerosol diffusion swimming motion determination method and device and a storage medium. The method comprises the following steps: acquiring the total duration of an accident and the initial spatial position distribution of aerosol particles; dividing the total duration into a plurality of time steps, dividing the computational domain of the containment into a plurality of computational domain nodes, and dividing the aerosol particles into a plurality of particle size intervals; selecting a first time step, and carrying out iterative computation on a plurality of computational domain nodes in the containment to obtain thermal hydraulic parameters; carrying out stress balance calculation on the aerosol particles to obtain diffusion swimming movement of the aerosol particles; updating the initial spatial position distribution of the aerosol particles to obtain target spatial position distribution of the aerosol particles; and traversing the thermal hydraulic parameters corresponding to the plurality of time steps and the target spatial position distribution, and determining the movement result of the radioactive aerosol. According to the invention, fine space division is realized, so that the steam condensation removal speed of the aerosol under the containment cooling condition can be evaluated more accurately.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear emergency response, and in particular to a method, a device and a storage medium for determining radioactive aerosol diffusion phoresis motion. Background Art

[0002] After a nuclear accident occurs in a third-generation nuclear power plant, a large amount of high-temperature water vapor and radioactive aerosols will be released into the containment. The third-generation nuclear power has good heat removal performance. Cooling will cause water vapor cooling on the heat exchanger wall of the containment, thereby removing the radioactive aerosols and preventing the leakage of radioactive materials. Therefore, it is necessary to evaluate the steam condensation removal rate of aerosols under the cooling conditions of the containment, which is of great significance to the assessment of radioactive source items and safety design of passive containment.

[0003] In the event of an accident, the assessment of aerosol removal rate within the containment space is usually analyzed using theoretical models based on a large number of simplifying assumptions; in terms of experimental analysis, the current diffusion phoresis research methods mostly focus on a single spatial uniformity parameter.

[0004] However, under actual cooling conditions, the environment inside the containment is very complex, and the comprehensive effect of steam condensation on aerosol removal is strong. In addition, the diffusiophoretic motion of aerosol particles in actual conditions is directly related to the water vapor condensation condition on the wall, and is not a single spatial distribution. The current experimental homogenization analysis method is difficult to describe the diffusiophoretic effect when the thermal-hydraulic parameters are unevenly distributed, and the spatial refinement is insufficient, resulting in errors in the evaluation of the steam condensation removal rate of aerosols under containment cooling conditions.

[0005] The above problems need to be solved urgently. Summary of the invention

[0006] The invention discloses a method, a device and a storage medium for determining radioactive aerosol diffusivitation movement, aiming to solve the technical problems existing in the prior art.

[0007] The present invention adopts the following technical solutions:

[0008] On the one hand, the present invention provides a method for determining the diffusiophoretic motion of radioactive aerosols, which includes: obtaining the total duration from the occurrence of an accident to the end of the accident, and the initial spatial position distribution of aerosol particles in the containment during the accident; dividing the total duration into multiple time steps, dividing the computational domain of the containment into multiple computational domain nodes, and dividing the aerosol particles into multiple particle size intervals; selecting a first time step, iteratively calculating the multiple computational domain nodes in the containment, and obtaining thermal-hydraulic parameters corresponding to the first time step, wherein the first time step is the current time step among the multiple time steps; based on the thermal-hydraulic parameters, performing force balance calculations on the aerosol particles corresponding to the multiple particle size intervals, respectively, to obtain the diffusiophoretic motion of the aerosol particles; based on the diffusiophoretic motion, updating the initial spatial position distribution of the aerosol particles, and obtaining the target spatial position distribution of the aerosol particles; traversing the thermal-hydraulic parameters corresponding to the multiple time steps, and the target spatial position distribution of the aerosol particles corresponding to the multiple time steps, to determine the motion results of the non-steady-state radioactive aerosol on the containment computational domain.

[0009] Optionally, the first time step is selected, and the multiple computational domain nodes in the containment are iteratively calculated to obtain thermal-hydraulic parameters corresponding to the first time step, including: at multiple computational domain nodes, based on the transport equation of the Euler system, solving the airflow movement in the computational domain in the containment; based on the component transport model of fluid mechanics, calculating the mixed flow of the accident water vapor source term and air, wherein the accident water vapor source term is used to indicate the amount, temperature and pressure of water vapor released from the source of the containment in the event of an accident; based on the airflow movement and the mixed flow, simplifying the mass transfer and heat transfer model to obtain thermal-hydraulic parameters, wherein the mass transfer and heat transfer model is used to indicate the condensation process of water vapor on the wall of the containment.

[0010] Optionally, the mass transfer and heat transfer model is simplified based on the airflow movement and the mixed flow to obtain thermal-hydraulic parameters, including: determining the water vapor partial pressure value of the water vapor in the containment; when the water vapor partial pressure value reaches the critical point of condensation, obtaining the mass transfer flow rate based on the mass transfer and heat transfer model, wherein the mass transfer flow rate is used to indicate the amount of mass reduction of water vapor components caused by the condensation process of the water vapor on the wall; obtaining the heat transfer flow rate based on the mass transfer and heat transfer model and the mass transfer flow rate, wherein the heat transfer flow rate is used to indicate the amount of heat transfer caused by the condensation process of the water vapor on the wall; based on the mass transfer flow rate and the heat transfer flow rate, coupled with the airflow movement and the mixed flow, the thermal-hydraulic parameters are obtained.

[0011] Optionally, determining the water vapor partial pressure value of the water vapor in the containment includes: determining the water vapor partial pressure value based on the Clapeyron equation; the Clapeyron equation is calculated as follows:

[0012]

[0013] Where p is the partial pressure of water vapor, T is the temperature in the heat trap connected to the containment, ΔH vap is the latent heat of vaporization of water vapor, and R is the gas constant.

[0014] Optionally, obtaining the mass transfer flow rate based on the mass transfer and heat transfer model includes: determining the mass transfer flow rate based on a condensation formula; the condensation formula is calculated as follows:

[0015]

[0016] Among them, q m is the mass transfer rate, W s is the mass fraction of water vapor, ρ is the gas density, D is the mass effective diffusion coefficient, v is the volume of water vapor, and n is the number concentration of the accident water vapor source term and the mixed gas of air.

[0017] Optionally, obtaining the heat transfer flow rate based on the mass transfer and heat transfer model and the mass transfer flow rate includes: determining the heat transfer flow rate based on a condensation heat flow formula; the condensation heat flow formula is calculated as follows:

[0018] H m =q m h s

[0019] Among them, H m is the heat transfer flow rate, q m is the mass transfer rate, h s is the specific enthalpy of saturated steam at the corresponding pressure.

[0020] Optionally, based on the thermal-hydraulic parameters, force balance calculation is performed on the aerosol particles corresponding to the multiple particle size intervals respectively to obtain the diffusophore motion of the aerosol particles, including: constructing a force balance equation for the aerosol particles in a Lagrangian system based on the thermal-hydraulic parameters; determining the modal region in which the aerosol particles are located, wherein the modal region is used to indicate the motion state of the aerosol particles; determining the diffusophore force corresponding to the aerosol particles in the modal region, wherein the diffusophore force is used to indicate the force of the aerosol particles being swept toward the wall by the flow formed by the water vapor in the condensation process; based on the diffusophore force, obtaining the diffusophore motion of the aerosol particles.

[0021] Optionally, constructing a force balance equation for aerosol particles in a Lagrangian system based on thermal hydraulic parameters includes: obtaining the movement of aerosol particles in a flow field; constructing a force balance equation for aerosol particles; the force balance equation is calculated as follows:

[0022]

[0023] in, is the inertial force of the aerosol particles, F D (uu p ) is the drag force, is the difference between gravity and buoyancy, F a is the diffusivitation force of the aerosol particles, u p is the velocity of the aerosol particles, u is the gas velocity, ρ p is the density of the aerosol particles.

[0024] Optionally, determining the modal zone in which the aerosol particles are located includes: determining the flow state of the water vapor in the condensation process based on a particle flow equation; determining the modal zone based on the flow state, wherein, when the flow state is greater than a first preset value, the aerosol particles are in a free molecule state, when the flow state is equal to a second preset value, the aerosol particles are in a transition zone, and when the flow state is less than the second preset value, the aerosol particles are in a slip zone, and the first preset value is greater than or equal to the second preset value; wherein the particle flow equation is calculated as follows:

[0025]

[0026] Among them, K n is the flow state, λ is the mean free path of the mixed gas of the accident water vapor source term and air; d p is the diameter of the aerosol particles.

[0027] Optionally, when the modal region is a slip region, determining the diffusophore corresponding to the aerosol particle in the modal region includes: calculating the diffusophore of the aerosol particle in the slip region as follows:

[0028]

[0029] Where: SD is the slip zone, η is the viscosity of the mixed gas, R0 is the radius of the aerosol particle, σ 12 is the ratio of the diameter to the mass of the mixed gas, is the gradient of the water vapor molar composition, D 12 is the diffusion coefficient, F SD ∈F a .

[0030] Optionally, when the modal region is a transition region, determining the diffusion phoretic force corresponding to the aerosol particles in the modal region includes: calculating the diffusion phoretic force of the aerosol particles in the transition region as follows:

[0031]

[0032] Where D is the transition zone, R is the radius of the aerosol particle, n is the number concentration of the gas mixture, m is the mass of the aerosol particle, k is the Boltzmann constant, T is the temperature in the heat trap device connected to the containment, and F D ∈F a .

[0033] According to another aspect of an embodiment of the present invention, a device for determining radioactive aerosol diffusion and phoretic motion is also provided, including: an acquisition module, used to obtain the total time from the start of the accident to the end of the accident, and the initial spatial position distribution of aerosol particles in the containment during the accident; a division module, used to divide the total time into multiple time steps, divide the calculation domain of the containment into multiple calculation domain nodes, and divide the aerosol particles into multiple particle size intervals; a thermal-hydraulic parameter determination module, used to select a first time step, iteratively calculate the multiple calculation domain nodes in the containment, and obtain the thermal-hydraulic parameters corresponding to the first time step, wherein the first time step step is the current time step among the multiple time steps; a diffusion-phoresis motion determination module is used to perform force balance calculation on the aerosol particles corresponding to the multiple particle size intervals respectively based on the thermal-hydraulic parameters, so as to obtain the diffusion-phoresis motion of the aerosol particles; an updating module is used to update the initial spatial position distribution of the aerosol particles based on the diffusion-phoresis motion, so as to obtain the target spatial position distribution of the aerosol particles; a motion result module is used to traverse the thermal-hydraulic parameters corresponding to the multiple time steps, and the target spatial position distribution of the aerosol particles corresponding to the multiple time steps, so as to determine the motion result of the non-steady-state radioactive aerosol on the containment calculation domain.

[0034] According to another aspect of an embodiment of the present invention, a non-volatile storage medium is provided, wherein the non-volatile storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded by a processor and executing any one of the radioactive aerosol diffusophore movement determination methods.

[0035] According to another aspect of an embodiment of the present invention, a computer program product is provided, comprising a computer program, wherein when the computer program is executed by a processor, the steps of any one of the methods for determining the diffusivities of radioactive aerosols are implemented.

[0036] The technical solution adopted by the present invention can achieve at least one of the following beneficial effects:

[0037] In an embodiment of the present invention, the total time from the occurrence of the accident to the end of the accident and the initial spatial position distribution of aerosol particles in the containment during the accident are obtained; the total time is divided into multiple time steps, the calculation domain of the containment is divided into multiple calculation domain nodes, and the aerosol particles are divided into multiple particle size intervals; a first time step is selected, and the multiple calculation domain nodes in the containment are iteratively calculated to obtain thermal-hydraulic parameters corresponding to the first time step, wherein the first time step is the current time step in the multiple time steps; based on the thermal-hydraulic parameters, a force balance calculation is performed on the aerosol particles corresponding to the multiple particle size intervals respectively to obtain the diffusion phoresis motion of the aerosol particles; based on the diffusion phoresis motion, the aerosol particles are updated. The initial spatial position distribution of the aerosol particles is obtained to obtain the target spatial position distribution of the aerosol particles; the thermal-hydraulic parameters corresponding to the multiple time steps and the target spatial position distribution of the aerosol particles corresponding to the multiple time steps are traversed to determine the movement results of the non-steady-state radioactive aerosol on the containment calculation domain, thereby achieving the purpose of dividing the time, the containment calculation domain and the aerosol particle interval, and performing fine analysis on the multiple containment calculation domains and the aerosol particle intervals in each time step, thereby realizing the technical effect of fine spatial division, making the steam condensation removal rate evaluation of the aerosol under the containment cooling condition more accurate, and further solving the technical problem of error in the steam condensation removal rate evaluation of the aerosol under the containment cooling condition due to the lack of spatial refinement. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments, which constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions explain the present invention and do not constitute improper limitations on the present invention. In the drawings:

[0039] Figure 1 is a flow chart of a method for determining radioactive aerosol diffusivitation movement in Example 1 of the present invention;

[0040] Figure 2 It is a distribution diagram of the computational domain nodes in the containment of a method for determining the diffusivitation movement of a radioactive aerosol in Example 1 of the present invention;

[0041] Figure 3 is a water vapor concentration distribution diagram of a method for determining radioactive aerosol diffusophore movement in Example 1 of the present invention;

[0042] Figure 4is a force diagram of aerosol particles in a method for determining radioactive aerosol diffusivitation motion in Example 1 of the present invention;

[0043] Figure 5 is a flow chart of an optional method for determining radioactive aerosol diffusivitation movement in Example 2 of the present invention;

[0044] Figure 6 It is a schematic diagram of the structure of a radioactive aerosol diffusivitation movement determination device in Example 3 of the present invention. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. In the description of the present invention, it should be noted that the term "or" is usually used in the sense of including "and / or", unless the content clearly indicates otherwise.

[0046] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a magnetic connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three or more, etc., unless otherwise clearly and specifically limited.

[0047] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] First, to facilitate understanding of the embodiments of the present invention, some terms or nouns involved in the present invention are explained below:

[0049] Radioactive aerosol refers to a dispersed system formed by solid or liquid particles containing radionuclides suspended in the air or other gases.

[0050] Diffusion phoresis refers to the net movement of particles due to uneven distribution of gas molecules. When there is a concentration gradient in the gas medium, the diffusion rate of the substance in one direction will be significantly greater than that in other directions, causing the particles to move in the same direction as the diffusion direction under the impact of the diffusing molecules.

[0051] In order to solve the problems existing in the prior art, the embodiments of the present application provide a method, device and storage medium for determining the diffusivitation movement of radioactive aerosols.

[0052] Example 1

[0053] This embodiment provides a method for determining the diffusivitation movement of radioactive aerosols, such as Figure 1 As shown, Figure 1 is a flow chart of a method for determining radioactive aerosol diffusivitation in embodiment 1 of the present invention, the method comprising:

[0054] Step S102, obtaining the total duration from the start of the accident to the end of the accident, and the initial spatial position distribution of aerosol particles in the containment during the accident;

[0055] Optionally, a nuclear reaction accident occurs in a nuclear reactor core, during which some radioactive aerosol particles are generated. These aerosol particles diffuse into the containment vessel, where they are collected to prevent them from diffusing into the external environment and causing radioactive damage to on-site workers.

[0056] Optionally, the time from the beginning to the end of the nuclear reaction accident is taken as the accident time. During the accident time, it is necessary to determine the movement process of the diffused aerosol particles, so as to infer whether the aerosol particles are completely removed, and then the passive containment radioactive source item assessment and safety design can be carried out.

[0057] Step S104, dividing the total duration into multiple time steps, dividing the calculation domain of the containment into multiple calculation domain nodes, and dividing the aerosol particles into multiple particle size intervals;

[0058] Optionally, the computational domain division of the containment should ensure that the multiple computational domain nodes are encrypted in the area where diffusion and phoresis mainly occur, and judged by the corresponding judgment criteria to ensure the applicability of the subsequent wall model. After the accident, a large amount of water vapor is generated to form a condensation process on the wall of the containment. The condensed water vapor will remove the aerosol particles. Therefore, the applicability of the wall model is the applicability of the computational domain of the containment. Figure 2 As shown, Figure 2 It is a distribution diagram of the computational domain nodes in the containment of a method for determining radioactive aerosol diffusivitation in Example 1 of the present invention.

[0059] Optionally, the judgment criterion is to judge the applicability of the wall model according to the wall y+ value judgment criterion to ensure that each selected wall model has a suitable application range. The specific wall y+ value judgment criterion is as follows:

[0060]

[0061] Where y is the distance from a point on the boundary layer to the wall, u τ is the friction velocity near the wall, v is the kinematic viscosity. It should be noted that the boundary layer refers to a fluid layer with a large velocity gradient formed near the wall due to the viscosity of the fluid when the water vapor in the containment flows through the solid wall. The velocity of the water vapor in the boundary layer gradually increases with the distance from the wall until it reaches the mainstream velocity. The thickness of the boundary layer is an important parameter to describe the characteristics of the boundary layer. It represents the distance from the wall to the point where the velocity reaches 99% of the mainstream velocity.

[0062] Optionally, node independence verification and time step independence verification are required for the computational domain node division process and the total time division process; among them, node independence verification mainly evaluates the sensitivity of the calculation results to the density of the computational domain nodes. In numerical calculations, the density of the computational domain nodes will directly affect the accuracy and efficiency of the calculation results. Time step independence verification evaluates the sensitivity of the calculation results to the size of the time step. In transient calculations, the selection of the time step affects the convergence and accuracy of the calculation.

[0063] Specifically, the process of node independence verification usually includes: Changing node density: Observe the changes in calculation results by continuously changing the density of nodes in the computational domain, that is, increasing or decreasing the number of nodes. Evaluating result changes: Analyze the differences in calculation results under different computational domain node densities. If the differences are within the allowed range, it is considered that the calculation results are no longer related to the computational domain node density, that is, the influence of the density of the computational domain nodes on the calculation results can be ignored. Determine the optimal node density: Under the premise of meeting the calculation accuracy requirements, select the computational domain node density with the highest calculation efficiency as the final computational domain node division criterion.

[0064] Specifically, the process of time step independence verification usually includes: Select different time steps: Select different time steps for calculation while keeping other calculation parameters unchanged. Observe the calculation results: Analyze the differences in calculation results under different time steps, especially pay attention to the parameters and physical quantities that are sensitive to the time step. Determine a reasonable time step: Under the premise of ensuring the accuracy and stability of the calculation results, select a time step that is neither too large nor too small to balance the calculation accuracy and efficiency.

[0065] Optionally, the aerosol is divided into different particle size intervals according to a source term particle size distribution density function, and the actual source term particle size distribution is fitted using a probability density function, which uses a log-normal distribution function or a Rosen-Rammler distribution function (Rosin-Rammler).

[0066] Step S106, selecting a first time step, performing iterative calculations on multiple computational domain nodes in the containment, and obtaining thermal-hydraulic parameters corresponding to the first time step, wherein the first time step is the current time step among the multiple time steps;

[0067] In some preferred embodiments, a first time step is selected, and multiple computational domain nodes in the containment are iteratively calculated to obtain thermal-hydraulic parameters corresponding to the first time step, including: at multiple computational domain nodes, based on the transport equation of the Euler system, solving the airflow movement in the computational domain in the containment; based on the component transport model of fluid mechanics, calculating the mixed flow of the accident water vapor source term and air, wherein the accident water vapor source term is used to indicate the amount, temperature and pressure of water vapor released from the source of the containment in the event of an accident; based on the airflow movement and the mixed flow, simplifying the mass transfer and heat transfer model to obtain thermal-hydraulic parameters, wherein the mass transfer and heat transfer model is used to indicate the condensation process of water vapor on the wall of the containment.

[0068] Optionally, the transport equation of the Euler system is used to solve the airflow motion in the containment computational domain at each computational domain node position, wherein the solution of the airflow motion is specifically the general fluid conservation equation of computational fluid dynamics. The mixed flow of the accident water vapor source term and air is determined using the component transport equation of computational fluid dynamics.

[0069] Optionally, the purpose of simplifying the mass transfer and heat transfer model is to calculate the condensation of high-temperature and high-pressure water vapor on the wall in the heat sink environment connected to the containment, and provide input for the aerosol diffusophoresis calculation. The specific method of simplifying the mass transfer and heat transfer model is to ignore the droplets generated by the condensation process of water vapor when it encounters cooling, and only consider the mass reduction of water vapor components and the heat transfer process generated by the condensation process of water vapor when it encounters cooling near the wall, thereby simplifying the mass transfer and heat transfer model.

[0070] It should be noted that the cold condensation process near the wall refers to the condensation of water vapor only at the first layer of nodes near the wall, where the first layer of nodes refers to the first computational domain node that is adjacent to the wall and exchanges heat with it. This computational domain node is located at the interface between the fluid and the wall. Specifically, when water vapor flows over a cold wall, the water vapor will undergo a phase change near the wall, from gas to liquid, which is a condensation process. The temperature, pressure, humidity and other parameters of the first computational domain node will change as the condensation process progresses, thereby affecting the flow field and temperature field of the entire computational domain. For example Figure 3 As shown, Figure 3 is a water vapor concentration distribution diagram of a radioactive aerosol diffusivitation motion determination method in Example 1 of the present invention. It should be noted that, Figure 3 for Figure 2 The water vapor concentration distribution in the area circled by the middle rectangle.

[0071] In some preferred embodiments, based on the air flow movement and mixed flow, the mass transfer and heat transfer model is simplified to obtain thermal-hydraulic parameters, including: determining the water vapor partial pressure value of water vapor in the containment; when the water vapor partial pressure value reaches the critical point of condensation, based on the mass transfer and heat transfer model, obtaining the mass transfer flow rate, wherein the mass transfer flow rate is used to indicate the amount of mass reduction of water vapor components caused by the condensation process of water vapor on the wall; based on the mass transfer and heat transfer model and the mass transfer flow rate, obtaining the heat transfer flow rate, wherein the heat transfer flow rate is used to indicate the amount of heat transfer caused by the condensation process of water vapor on the wall; based on the mass transfer flow rate and the heat transfer flow rate, coupled with the air flow movement and mixed flow, the thermal-hydraulic parameters are obtained.

[0072] Optionally, the mass reduction of water vapor components caused by the cold condensation process needs to be determined by determining whether the partial pressure of water vapor reaches the critical point of condensation, that is, determining the saturated vapor pressure of water vapor at the heat sink temperature. When the partial pressure of water vapor is large, it means that water vapor forms pressure in the containment, causing the movement speed of water vapor molecules to accelerate, making it easier to collide with the wall, thus forming a condensation process; when the partial pressure of water vapor is small, it means that water vapor may not hit the wall quickly, resulting in no condensation. The mass reduction of water vapor components caused by the cold condensation process of water vapor near the wall requires the calculation of the mass transfer flow of water vapor condensation. It should be noted that the mass transfer flow calculation method ignores the heat transfer of the condensation liquid film and only considers convective mass transfer and condensation mass transfer; in the heat transfer process generated by the cold condensation process of water vapor near the wall, the mass of water vapor decreases (it becomes liquid after condensation, resulting in a decrease in water vapor), and the condensation heat flow caused by the condensation of water vapor needs to be calculated.

[0073] In some preferred embodiments, determining the water vapor partial pressure value of water vapor in the containment vessel includes: determining the water vapor partial pressure value based on the Clapeyron equation; the Clapeyron equation is calculated as follows:

[0074]

[0075] Where p is the partial pressure of water vapor, T is the temperature inside the heat trap connected to the containment, ΔH vap is the latent heat of vaporization of water vapor, and R is the gas constant.

[0076] In some preferred embodiments, based on the mass transfer and heat transfer model, the mass transfer flow rate is obtained, including: determining the mass transfer flow rate based on the condensation formula; the condensation formula is calculated as follows:

[0077]

[0078] Among them, q m is the mass transfer rate, W s is the mass fraction of water vapor, ρ is the gas density, D is the mass effective diffusion coefficient, v is the volume of water vapor, and n is the number concentration of the accident water vapor source term and the mixed gas of air.

[0079] In some preferred embodiments, based on the mass transfer and heat transfer model and the mass transfer flow rate, the heat transfer flow rate is obtained, including: determining the heat transfer flow rate based on the condensation heat flow formula; the condensation heat flow formula is calculated as follows:

[0080] H m =q m h s

[0081] Among them, H m is the heat transfer flow rate, q m is the mass transfer rate, h s is the specific enthalpy of saturated steam at the corresponding pressure.

[0082] Step S108, based on the thermal hydraulic parameters, force balance calculation is performed on the aerosol particles corresponding to the plurality of particle size intervals to obtain the diffusion phoresis motion of the aerosol particles;

[0083] In some preferred embodiments, based on thermal-hydraulic parameters, force balance calculations are performed on aerosol particles corresponding to multiple particle size intervals to obtain the diffusophore motion of the aerosol particles, including: constructing a force balance equation for the aerosol particles in a Lagrangian system based on the thermal-hydraulic parameters; determining the modal region in which the aerosol particles are located, wherein the modal region is used to indicate the motion state of the aerosol particles; determining the diffusophore force corresponding to the aerosol particles in the modal region, wherein the diffusophore force is used to indicate the force of the aerosol particles being swept toward the wall by the flow formed by the water vapor in the condensation process; based on the diffusophore force, obtaining the diffusophore motion of the aerosol particles.

[0084] Optionally, in the Lagrangian system, a force balance model of aerosol particles is constructed. Specifically, the movement of a single aerosol particle in the flow field is tracked. By constructing a force balance equation for the aerosol particles, the diffusion-phoretic force, drag force, and inertial force on the aerosol particles in the flow field are considered, and the influence of changes in the thermal-hydraulic environment on the movement of aerosol particles is calculated, thereby realizing mechanistic calculations. Based on mechanistic calculations, the behavior process of the diffusion-phoretic movement of aerosol particles can be obtained. Figure 4 As shown, Figure 4 It is a force diagram of aerosol particles in a method for determining radioactive aerosol diffusivitation motion in Example 1 of the present invention.

[0085] In some preferred embodiments, based on thermal hydraulic parameters, a force balance equation is constructed for aerosol particles in a Lagrangian system, including: obtaining the movement of aerosol particles in a flow field; constructing a force balance equation for aerosol particles; the force balance equation is calculated as follows:

[0086]

[0087] in, is the inertial force of aerosol particles, F D (uu p ) is the drag force, is the difference between gravity and buoyancy, F a is the diffusion-phoretic force of aerosol particles, u p is the velocity of aerosol particles, u is the gas velocity, ρ p is the density of aerosol particles.

[0088] In some preferred embodiments, determining the modal region in which the aerosol particles are located includes: determining the flow state of water vapor in the condensation process based on the particle flow equation; determining the modal region based on the flow state, wherein, when the flow state is greater than a first preset value, the aerosol particles are in a free molecule state, when the flow state is equal to a second preset value, the aerosol particles are in a transition zone, and when the flow state is less than the second preset value, the aerosol particles are in a slip zone, and the first preset value is greater than or equal to the second preset value; wherein the particle flow equation is calculated as follows:

[0089]

[0090] Among them, K n is the flow state, λ is the mean free path of the mixed gas between the accident water vapor source term and air; d p is the diameter of aerosol particles.

[0091] It should be noted that, in actual conditions, the first preset value is much larger than the second preset value. When the flow state is larger than the first preset value, the aerosol particles are in a free molecular state. The aerosol particles in the free molecular state need to be removed by spraying droplets, and they cannot be completely removed by water vapor alone. Therefore, in this state, it is not taken into consideration. Only the situation where the aerosol particles are in the slip zone and the transition zone is considered.

[0092] In some preferred embodiments, when the modal region is a slip region, determining the diffusophore corresponding to the aerosol particle in the modal region includes: calculating the diffusophore of the aerosol particle in the slip region as follows:

[0093]

[0094] Where: SD is the slip zone, η is the viscosity of the mixed gas, R0 is the radius of the aerosol particle, σ 12 is the ratio of the diameter to the mass of the mixed gas, is the gradient of the water vapor molar composition, D 12 is the diffusion coefficient, F SD ∈F a .

[0095] It should be noted that in the slip zone, there is a phenomenon of water vapor diffusing in the non-condensable gas, and the diffusion and phoretic force of aerosol particles needs to take this factor into account.

[0096] Optional, σ 12 is the ratio of the diameter to the mass of the mixed gas, which is determined as follows:

[0097]

[0098] Where d1 is the molecular diameter of water vapor, d 12 is the average molecular diameter of water vapor and non-condensable gas, m1 is the molecular mass of water vapor, and m2 is the molecular mass of non-condensable gas.

[0099] In some preferred embodiments, when the modal region is a transition region, determining the diffusivitational force corresponding to the aerosol particles in the modal region includes: the diffusivitational force of the aerosol particles in the transition region is calculated as follows:

[0100]

[0101] Where D is the transition zone, R is the radius of the aerosol particle, n is the number concentration of the gas mixture, m is the mass of the aerosol particle, k is the Boltzmann constant, T is the temperature inside the heat trap connected to the containment, and F D ∈F a .

[0102] Step S110, based on the diffusion phoresis movement, updating the initial spatial position distribution of the aerosol particles to obtain the target spatial position distribution of the aerosol particles;

[0103] Optionally, based on the diffusion phoresis motion, the moving position of the aerosol particles can be obtained, thereby determining the target spatial position distribution of the aerosol particles in the next time step.

[0104] Step S112, traverses the thermal-hydraulic parameters corresponding to multiple time steps and the target spatial position distribution of aerosol particles corresponding to multiple time steps to determine the movement result of the non-steady-state radioactive aerosol on the containment calculation domain.

[0105] Optionally, the movement process of radioactive aerosol particles is a time-dependent movement. In the above method, the target spatial position distribution of aerosol particles in the first time step is obtained, and the target spatial position distribution corresponding to the aerosol particles in each time step is obtained. According to the order of time steps, the above target spatial position distribution is formed into a dynamic movement, which is the movement result of the non-steady-state radioactive aerosol.

[0106] Through the above steps S102 to S112, the purpose of dividing the time, containment calculation domain and aerosol particle interval, and performing fine analysis on multiple containment calculation domains and aerosol particle intervals in each time step is achieved, thereby realizing the spatial fine division, making the evaluation of the steam condensation removal rate of aerosol under containment cooling conditions more accurate, and further solving the technical problem of errors in the evaluation of the steam condensation removal rate of aerosol under containment cooling conditions due to insufficient spatial refinement.

[0107] Example 2

[0108] Based on the above embodiments and optional embodiments, the present invention also proposes an optional implementation mode: Figure 5 is a flow chart of an optional method for determining radioactive aerosol diffusivitation in Example 2 of the present invention, such as Figure 5 As shown, the method includes:

[0109] Step S1, dividing the containment calculation domain of the accident object into a number of calculation domain nodes, dividing the physical time t during the accident into different time steps (t0, t1...tn), and dividing the aerosol particles into different particle size intervals;

[0110] Step S2, iteratively solving the transport equation, component transport model and simplified mass transfer and heat transfer model for the containment calculation domain nodes at the current time step (first time step) to obtain the thermal hydraulic parameters of the containment under condensation conditions at the current time step;

[0111] Step S3, solving the aerosol particle force balance equation for each radioactive aerosol particle in the computational domain node at the current time step, wherein the required physical parameters are obtained based on the computational domain node where the radioactive aerosol particle is located;

[0112] Step S4, updating the distribution of thermal hydraulic parameters in the containment calculation domain nodes and the target spatial position distribution of radioactive aerosol particles at the current time step;

[0113] Step S5, update the current time step to the next time step, start step S2 to continue iterative execution, if the calculation time physical time t has been reached, stop the calculation, at this time the non-steady-state radioactive aerosol motion results on the containment calculation domain have been obtained.

[0114] Through the above steps S1 to S5, it can be applied to evaluate the physical phenomenon of removing radioactive source terms when steam condenses during cooling in passive third-generation nuclear power. The simplified mass transfer and heat transfer model proposed can analyze the time evolution process of thermal hydraulic phenomena in the containment. The simplified mass transfer and heat transfer model also simplifies the two-phase flow into a single-phase flow to improve the calculation efficiency. The proposed diffusion-phoresis force balance model realizes the mechanism study related to the diffusion-phoresis behavior of aerosol particles and the water vapor condensation condition on the wall by coupling the thermal calculation process. The proposed refined calculation method can perform iterative calculations in the spatial and temporal dimensions in the containment calculation domain to realize the diffusion-phoresis analysis of the uneven distribution of thermal-hydraulic parameters.

[0115] Example 3

[0116] In this embodiment, a radioactive aerosol diffusion phoresis motion determination device is also provided, which is used to implement the above-mentioned embodiments and preferred embodiments, and the descriptions that have been made will not be repeated. As used below, the terms "module" and "device" can be a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0117] According to an embodiment of the present invention, there is also provided an embodiment of a device for implementing the above-mentioned method for determining the diffusivitation movement of radioactive aerosols. Figure 6 : is a schematic diagram of the structure of a radioactive aerosol diffusivitation movement determination device in Example 3 of the present invention, such as Figure 6 As shown, the above-mentioned radioactive aerosol diffusivation phoresis motion determination device includes: an acquisition module 401, a division module 402, a thermal hydraulic parameter determination module 403, a diffusivation phoresis motion determination module 404, an update module 405 and a motion result module 406, wherein:

[0118] The acquisition module 401 is used to obtain the total duration from the start of the accident to the end of the accident, and the initial spatial position distribution of aerosol particles in the containment during the accident;

[0119] A division module 402, connected to the acquisition module 401, is used to divide the total duration into a plurality of time steps, divide the calculation domain of the containment into a plurality of calculation domain nodes, and divide the aerosol particles into a plurality of particle size intervals;

[0120] The thermal hydraulic parameter determination module 403 is connected to the division module 402, and is used to select a first time step, perform iterative calculations on multiple computational domain nodes in the containment, and obtain thermal hydraulic parameters corresponding to the first time step, wherein the first time step is the current time step among the multiple time steps;

[0121] The diffusion phoresis motion determination module 404 is connected to the thermal hydraulic parameter determination module 403, and is used to calculate the force balance of aerosol particles corresponding to a plurality of particle size intervals based on the thermal hydraulic parameters to obtain the diffusion phoresis motion of the aerosol particles;

[0122] An updating module 405, connected to the diffusion phoresis motion determination module 404, is used to update the initial spatial position distribution of the aerosol particles based on the diffusion phoresis motion to obtain the target spatial position distribution of the aerosol particles;

[0123] The motion result module 406 is connected to the update module 405 and is used to traverse the thermal hydraulic parameters corresponding to multiple time steps and the target spatial position distribution of aerosol particles corresponding to multiple time steps to determine the motion result of the non-steady-state radioactive aerosol on the containment calculation domain.

[0124] It should be noted that the above modules can be implemented by software or hardware. For example, for the latter, it can be implemented in the following ways: the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0125] It should be noted that the acquisition module 401, the division module 402, the thermal hydraulic parameter determination module 403, the diffusion phoresis motion determination module 404, the update module 405 and the motion result module 406 are the same as the examples and application scenarios implemented by the corresponding steps, but are not limited to the contents disclosed in the above embodiments. It should be noted that the above modules can be run in a computer terminal as part of the device.

[0126] It should be noted that the optional or preferred implementation of this embodiment can refer to the relevant description in the embodiment, which will not be repeated here.

[0127] The above-mentioned radioactive aerosol diffusion phoresis motion determination device may also include a processor and a memory. The above-mentioned acquisition module 401, division module 402, thermal-hydraulic parameter determination module 403, diffusion phoresis motion determination module 404, update module 405 and motion result module 406 are all stored in the memory as program modules, and the processor executes the above-mentioned program modules stored in the memory to realize the corresponding functions.

[0128] The processor includes a kernel, which retrieves the corresponding program module from the memory. The kernel may be one or more. The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. The memory includes at least one memory chip.

[0129] According to an embodiment of the present application, an embodiment of a non-volatile storage medium is also provided. Optionally, in this embodiment, the non-volatile storage medium includes a stored program, wherein when the program is executed, the device where the non-volatile storage medium is located is controlled to execute any of the above-mentioned radioactive aerosol diffusivitation movement determination methods.

[0130] Optionally, in this embodiment, the non-volatile storage medium may be located in any computer terminal in a computer terminal group in a computer network, or in any mobile terminal in a mobile terminal group, and the non-volatile storage medium includes a stored program.

[0131] Optionally, when the program is running, the device where the non-volatile storage medium is located is controlled to perform the following functions: obtain the total duration from the start of the accident to the end of the accident, and the initial spatial position distribution of aerosol particles in the containment during the accident; divide the total duration into multiple time steps, divide the calculation domain of the containment into multiple calculation domain nodes, and divide the aerosol particles into multiple particle size intervals; select a first time step, iteratively calculate the multiple calculation domain nodes in the containment, and obtain the thermal-hydraulic parameters corresponding to the first time step, wherein the first time step is the current time step among the multiple time steps; based on the thermal-hydraulic parameters, perform force balance calculations on the aerosol particles corresponding to the multiple particle size intervals, and obtain the diffusion-phoretic motion of the aerosol particles; based on the diffusion-phoretic motion, update the initial spatial position distribution of the aerosol particles, and obtain the target spatial position distribution of the aerosol particles; traverse the thermal-hydraulic parameters corresponding to multiple time steps, and the target spatial position distribution of the aerosol particles corresponding to multiple time steps, and determine the motion results of the non-steady-state radioactive aerosol on the containment calculation domain.

[0132] According to an embodiment of the present application, an embodiment of a processor is also provided. Optionally, in this embodiment, the processor is used to run a program, wherein when the program is run, any one of the above-mentioned methods for determining the diffusivities of radioactive aerosols is executed.

[0133] According to an embodiment of the present application, an embodiment of a computer program product is also provided. Optionally, in this embodiment, the computer program product includes a computer program, which, when executed by a processor, implements any of the steps of the radioactive aerosol diffusophore movement determination method.

[0134] Optionally, the above-mentioned computer program product, when executed on a data processing device, is suitable for executing a program that initializes the following method steps: obtaining the total time from the occurrence of the accident to the end of the accident, and the initial spatial position distribution of aerosol particles in the containment during the accident; dividing the total time into multiple time steps, dividing the calculation domain of the containment into multiple calculation domain nodes, and dividing the aerosol particles into multiple particle size intervals; selecting a first time step, iteratively calculating the multiple calculation domain nodes in the containment, and obtaining the thermal-hydraulic parameters corresponding to the first time step, wherein the first time step is the current time step among the multiple time steps; based on the thermal-hydraulic parameters, performing force balance calculations on the aerosol particles corresponding to the multiple particle size intervals, respectively, to obtain the diffusion-swimming motion of the aerosol particles; based on the diffusion-swimming motion, updating the initial spatial position distribution of the aerosol particles, and obtaining the target spatial position distribution of the aerosol particles; traversing the thermal-hydraulic parameters corresponding to multiple time steps, and the target spatial position distribution of the aerosol particles corresponding to multiple time steps, to determine the motion results of the non-steady-state radioactive aerosol on the containment calculation domain.

[0135] An embodiment of the present invention provides an electronic device, which includes a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, the following steps are implemented: obtaining the total duration from the occurrence of an accident to the end of the accident, and the initial spatial position distribution of aerosol particles in the containment during the accident; dividing the total duration into multiple time steps, dividing the calculation domain of the containment into multiple calculation domain nodes, and dividing the aerosol particles into multiple particle size intervals; selecting a first time step, iteratively calculating multiple calculation domain nodes in the containment, and obtaining thermal-hydraulic parameters corresponding to the first time step, wherein the first time step is the current time step among the multiple time steps; based on the thermal-hydraulic parameters, performing force balance calculations on aerosol particles corresponding to the multiple particle size intervals, respectively, to obtain the diffusion-swimming motion of the aerosol particles; based on the diffusion-swimming motion, updating the initial spatial position distribution of the aerosol particles, and obtaining the target spatial position distribution of the aerosol particles; traversing the thermal-hydraulic parameters corresponding to multiple time steps, and the target spatial position distribution of the aerosol particles corresponding to the multiple time steps, to determine the motion results of the non-steady-state radioactive aerosol on the calculation domain of the containment.

[0136] The above sequence of the embodiments of the present invention is for description only and does not represent the superiority or inferiority of the embodiments.

[0137] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0138] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the above modules can be a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, modules or indirect coupling or communication connection of modules, which can be electrical or other forms.

[0139] The modules described above as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on multiple modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment.

[0140] In addition, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of software functional modules.

[0141] If the above-mentioned integrated module is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable non-volatile storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a non-volatile storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of the various embodiments of the present invention. The aforementioned non-volatile storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0142] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for determining the diffusivitation movement of radioactive aerosols, characterized in that: include: Obtain the total duration from the start of the accident to the end of the accident, as well as the initial spatial position distribution of aerosol particles in the containment during the accident; Dividing the total time into a plurality of time steps, dividing the computational domain of the containment into a plurality of computational domain nodes, and dividing the aerosol particles into a plurality of particle size intervals; Selecting a first time step, performing iterative calculations on the multiple computational domain nodes in the containment shell, and obtaining thermal-hydraulic parameters corresponding to the first time step, wherein the first time step is a current time step among the multiple time steps; Based on the thermal hydraulic parameters, force balance calculation is performed on the aerosol particles corresponding to the multiple particle size intervals to obtain the diffusion phoresis motion of the aerosol particles; Based on the diffusion phoresis movement, updating the initial spatial position distribution of the aerosol particles to obtain the target spatial position distribution of the aerosol particles; The thermal-hydraulic parameters corresponding to the multiple time steps and the target spatial position distribution of the aerosol particles corresponding to the multiple time steps are traversed to determine the movement result of the non-steady-state radioactive aerosol on the containment calculation domain.

2. The method for determining radioactive aerosol diffusophore motion according to claim 1, characterized in that: The selecting of the first time step, performing iterative calculation on the plurality of computational domain nodes in the containment, and obtaining thermal hydraulic parameters corresponding to the first time step, comprises: At a plurality of computational domain nodes, solving the airflow motion in the computational domain within the containment based on the transport equation of the Euler system; Based on the component transport model of fluid mechanics, the mixed flow of accident water vapor source term and air is calculated, wherein the accident water vapor source term is used to indicate the amount, temperature and pressure of water vapor released from the containment source in the event of an accident; Based on the air flow movement and the mixed flow, a mass transfer and heat transfer model is simplified to obtain thermal hydraulic parameters, wherein the mass transfer and heat transfer model is used to indicate the condensation process of water vapor on the wall of the containment.

3. The method for determining radioactive aerosol diffusophore motion according to claim 2, characterized in that: The mass transfer and heat transfer model is simplified based on the air flow movement and the mixed flow to obtain thermal hydraulic parameters, including: determining a water vapor partial pressure value of the water vapor in the containment; When the water vapor partial pressure reaches the critical point of condensation, a mass transfer flow rate is obtained based on the mass transfer and heat transfer model, wherein the mass transfer flow rate is used to indicate the amount of mass reduction of the water vapor component caused by the condensation process of the water vapor on the wall; Based on the mass transfer and heat transfer model and the mass transfer flow rate, a heat transfer flow rate is obtained, wherein the heat transfer flow rate is used to indicate the amount of heat transfer caused by the condensation process of the water vapor on the wall surface; The thermal hydraulic parameters are obtained based on the mass transfer flow rate and the heat transfer flow rate, coupled with the air flow motion and the mixed flow.

4. The method for determining radioactive aerosol diffusophore motion according to claim 3, characterized in that: Determining the water vapor partial pressure value of the water vapor in the containment vessel includes: Determining the water vapor partial pressure value based on the Clapeyron equation; The Clapeyron equation is calculated as follows: Where p is the partial pressure of water vapor, T is the temperature in the heat trap connected to the containment, ΔH vap is the latent heat of vaporization of water vapor, and R is the gas constant.

5. The method for determining radioactive aerosol diffusophore motion according to claim 3, characterized in that: The method of obtaining the mass transfer flow rate based on the mass transfer and heat transfer model includes: Based on the condensation formula, determining the mass transfer flow rate; The condensation formula is calculated as follows: Among them, q m is the mass transfer rate, W s is the mass fraction of water vapor, ρ is the gas density, D is the mass effective diffusion coefficient, v is the volume of water vapor, and n is the number concentration of the accident water vapor source term and the mixed gas of air.

6. The method for determining radioactive aerosol diffusophore motion according to claim 3, characterized in that: The step of obtaining the heat transfer flow rate based on the mass transfer and heat transfer model and the mass transfer flow rate includes: Determining the heat transfer flow rate based on the condensation heat flow formula; The condensation heat flow formula is calculated as follows: H m =q m h s Among them, H m is the heat transfer flow rate, q m is the mass transfer rate, h s is the specific enthalpy of saturated steam at the corresponding pressure.

7. The method for determining radioactive aerosol diffusophore motion according to claim 1, characterized in that: The method of performing force balance calculation on the aerosol particles corresponding to the plurality of particle size intervals based on the thermal hydraulic parameters to obtain the diffusion phoresis motion of the aerosol particles comprises: Based on the thermal hydraulic parameters, the force balance equation for aerosol particles is constructed in the Lagrangian system; Determining a modal region where the aerosol particles are located, wherein the modal region is used to indicate a motion state of the aerosol particles; Determining the diffusophore force corresponding to the aerosol particles in the modal region, wherein the diffusophore force is used to indicate the force of the aerosol particles being swept toward the wall by the flow formed by the water vapor in the condensation process; Based on the diffusophore force, the diffusophore motion of the aerosol particles is obtained.

8. The method for determining radioactive aerosol diffusophore motion according to claim 7, characterized in that: Based on the thermal hydraulic parameters, the force balance equation for aerosol particles is constructed in the Lagrangian system, including: Obtain the movement of aerosol particles in the flow field; Construct force balance equations for aerosol particles; The force balance equation is calculated as follows: in, is the inertial force of the aerosol particles, F D (uu p ) is the drag force, is the difference between gravity and buoyancy, F a is the diffusivitation force of the aerosol particles, u p is the velocity of the aerosol particles, u is the gas velocity, ρ p is the density of the aerosol particles.

9. The method for determining radioactive aerosol diffusophore motion according to claim 8, characterized in that: Determining the modal region where the aerosol particles are located comprises: Based on the particle flow equation, determine the flow state of the water vapor in the condensation process; Based on the flow state, the modal region is determined, wherein when the flow state is greater than a first preset value, the aerosol particles are in a free molecule state, when the flow state is equal to a second preset value, the aerosol particles are in a transition region, and when the flow state is less than a second preset value, the aerosol particles are in a slip region, and the first preset value is greater than or equal to the second preset value; Among them, the particle flow equation is calculated as follows: Among them, K n is the flow state, λ is the mean free path of the mixed gas of the accident water vapor source term and air; d p is the diameter of the aerosol particles.

10. The method for determining radioactive aerosol diffusophore motion according to claim 9, characterized in that: In the case where the modal region is a slip region, determining the diffusion phoretic force corresponding to the aerosol particles in the modal region includes: The diffusiophoretic force of the aerosol particles in the slip zone is calculated as follows: Where: SD is the slip zone, η is the viscosity of the mixed gas, R0 is the radius of the aerosol particle, σ 12 is the ratio of the diameter to the mass of the mixed gas, is the gradient of the water vapor molar composition, D 12 is the diffusion coefficient, F SD ∈F a .

11. The method for determining radioactive aerosol diffusophore motion according to claim 9, characterized in that: In the case where the modal region is a transition region, determining the diffusion phoretic force corresponding to the aerosol particles in the modal region includes: The diffusivities of the aerosol particles in the transition zone are calculated as follows: Where D is the transition zone, R is the radius of the aerosol particle, n is the number concentration of the gas mixture, m is the mass of the aerosol particle, k is the Boltzmann constant, T is the temperature in the heat trap device connected to the containment, and F D ∈F a .

12. A device for determining the diffusivitation movement of radioactive aerosols, characterized in that: include: The acquisition module is used to obtain the total duration from the start of the accident to the end of the accident, as well as the initial spatial position distribution of aerosol particles in the containment during the accident; A division module, used for dividing the total duration into a plurality of time steps, dividing the calculation domain of the containment into a plurality of calculation domain nodes, and dividing the aerosol particles into a plurality of particle size intervals; a thermal hydraulic parameter determination module, configured to select a first time step, perform iterative calculations on the plurality of computational domain nodes within the containment, and obtain thermal hydraulic parameters corresponding to the first time step, wherein the first time step is a current time step among the plurality of time steps; a diffusion phoresis motion determination module, configured to perform force balance calculation on the aerosol particles corresponding to the plurality of particle size intervals respectively based on the thermal hydraulic parameters, so as to obtain the diffusion phoresis motion of the aerosol particles; An updating module, configured to update the initial spatial position distribution of the aerosol particles based on the diffusion phoresis movement to obtain a target spatial position distribution of the aerosol particles; The motion result module is used to traverse the thermal-hydraulic parameters corresponding to the multiple time steps and the target spatial position distribution of the aerosol particles corresponding to the multiple time steps, and determine the motion results of the non-steady-state radioactive aerosol on the containment calculation domain.

13. A non-volatile storage medium, characterized in that: The non-volatile storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded by a processor and executing the method for determining the radioactive aerosol diffusivities according to any one of claims 1 to 11.

14. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method for determining the diffusivitation movement of a radioactive aerosol according to any one of claims 1 to 11 are implemented.

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