Method, system and equipment for solving aerosol particle size composition based on deposition simulation

Abstract

The present invention relates to a method, system, medium and equipment for solving aerosol particle size composition based on deposition simulation. The method includes establishing an atmospheric transmission model that takes into account aerosol particle size distribution and solubility. The model can simulate the special performance behaviors of aerosols of different particle sizes and solubility in meteorological processes such as transmission, diffusion, dry and wet deposition in the atmosphere, and provide reasonable data support for solving particle size distribution. The atmospheric transmission model that accurately simulates cumulative deposition is used to simulate, and the cumulative deposition characteristics of aerosols of different particle sizes are extracted as a basis for solving particle size distribution, thereby improving the accuracy of particle size distribution results. The non-negative least squares algorithm is used to solve the equation group. According to the compliance of the deposition simulation results and the monitoring, as well as the restriction that the sum of the percentages of aerosol components of each particle size is 1, the particle size distribution of the aerosol is solved with a non-negative numerical value, and the optimal solution of the aerosol particle size distribution is obtained and normalized, thereby improving the rationality of the particle size distribution results.

Description

Technical Field

[0001] The invention relates to a method, system, medium and equipment for solving aerosol particle size composition based on deposition simulation, and belongs to the technical field of environmental engineering. Background Art

[0002] The spatiotemporal distribution of aerosol pollutants under atmospheric transport and deposition is a crucial basis for assessing the consequences of a pollutant leak or emission, as well as for environmental impact assessments. Model simulations are typically used to reflect the consequences of aerosol transport. However, pollutant leaks can occur under complex meteorological conditions. The primary deposition mode of aerosol cesium-137 in the Fukushima nuclear accident was wet deposition, which is influenced by the aerosol's physical and chemical properties, particularly its particle size distribution.

[0003] Aerosol size distribution is closely linked to wet deposition processes, including in-cloud and subcloud wet removal. Aerosols in the boundary layer are carried into clouds by air currents and enriched through nucleation, condensation, and condensation. Upon reaching a certain threshold, condensation nuclei, which have absorbed radioactive aerosols, are activated into cloud droplets. Larger aerosols have a greater surface area and are more likely to collide with droplets, leading to their removal through in-cloud wet removal. When cloud droplets grow to a certain size, they form raindrops and fall to the ground, participating in the subcloud wet removal process. The mechanisms involved include Brownian diffusion, interception, and inertial collisions. The primary mechanism is primarily determined by aerosol size. For example, Brownian diffusion is more effective for aerosols with diameters less than 0.01 microns, while inertial collisions dominate for aerosols with diameters greater than 2 microns. Aerosol size distribution plays a crucial role in aerosol wet deposition. Therefore, obtaining an aerosol size distribution spectrum is crucial for accurately predicting and reproducing the spatial and temporal distribution of radionuclides and improving simulation accuracy. In addition, solubility also affects the wet deposition process. Aerosols that are easily soluble in water are more easily absorbed by cloud droplets and raindrops and removed by wet deposition.

[0004] However, in the event of a pollutant leak or emission, monitoring sites for aerosol size distribution are too sparse in both time and space, resulting in high human and material costs for mobile monitoring and difficulty obtaining sufficient information on measured aerosol particle size. Furthermore, aerosol size distribution measurement techniques are time-consuming and subject to high uncertainty, making them unrepresentative for aerosols released after a pollutant leak or emission. Establishing a reasonable aerosol size distribution spectrum based solely on particle size monitoring is currently a challenge in simulating microphysical processes in atmospheric diffusion models. Summary of the Invention

[0005] To address the above issues, one objective of the present invention is to provide a method for calculating aerosol particle size composition based on deposition simulation, capable of accurately calculating the aerosol particle size composition generated by pollutant leaks or emissions. Another objective of the present invention is to provide a system, medium, and equipment for calculating aerosol particle size composition based on deposition simulation.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for solving aerosol particle size composition based on deposition simulation, comprising the steps of:

[0008] Establish an atmospheric transport model that takes into account aerosol particle size distribution and solubility, and use the model to simulate deposition and calculate the cumulative deposition distribution data of different particle sizes;

[0009] Extract the cumulative sedimentation distribution data of different particle sizes and establish a particle size distribution solution equation set;

[0010] Solving the particle size distribution equations with non-negative numerical values ​​to obtain the aerosol particle composition;

[0011] Output aerosol particle size composition.

[0012] Furthermore, based on the online coupled model WRF-Chem, an atmospheric transport model considering aerosol particle size distribution and solubility was established.

[0013] Furthermore, the calculation of the cumulative deposition distribution data of different particle sizes includes:

[0014] 1) Extracting variables, including rainfall, temperature, humidity, and air pressure;

[0015] 2) Calculating cloud water content using the variables;

[0016] 3) calculating the wet deposition coefficients within and below the cloud based on the cloud water content;

[0017] 4) Calculating the deposition amount based on the in-cloud and under-cloud wet deposition coefficients, specifically by calculating the in-cloud and under-cloud wet deposition coefficients and the nuclide concentrations of the grids, and summing them in the vertical grid direction to obtain a two-dimensional spatial distribution of the deposition amount.

[0018] Furthermore, the atmospheric transmission model calculates the cloud wet deposition coefficient Λ according to formula (1):

[0019]

[0020] Where Λ is the cloud wet deposition coefficient, LWC is the cloud water content, p0 is the rainfall intensity, Δz is the vertical grid height, and f inc is the activation coefficient, finc Affected by aerosol particle size distribution and solubility

[0021] Furthermore, the atmospheric transmission model calculates the cloud wet deposition coefficient Λ according to formula (2):

[0022]

[0023] g(r)w-0.15+0.32r-3×10 -2 r 2 +9.34×10 -4 r 3

[0024] f(p0)=2.7×10 -4 p0-3.618×10 -6 p0 2

[0025] Where r is the aerosol radius, p0 is the rainfall intensity, g(r) is a function related only to the particle size, and f(p0) is a function related only to the rainfall intensity.

[0026] Furthermore, the extraction of the cumulative deposition distribution data of different particle sizes and the establishment of a particle size distribution solution equation group include:

[0027] Extracting n-1 grid deposition data of n particle sizes, and establishing n-1 equations based on the deposition simulation results and the monitoring compliance, wherein the n-1 equations and the equation whose particle size components add up to 1 form an equation system of n equations, wherein the equation system is a linear equation system;

[0028] The equation group is shown in formula (3):

[0029]

[0030] Among them, x is the vector composed of the percentage of each particle size, a i is the n-1 grid data randomly selected in the two-dimensional cumulative sedimentation distribution grid, μ i The n-1 grid data corresponding to the cumulative sedimentation monitoring.

[0031] Furthermore, in step S3, the n sets of equations are solved using a non-negative least squares algorithm, and the n particle sizes are normalized.

[0032] In a second aspect, the present invention provides an online coupled prediction system for aerosol in-cloud and below-cloud wet deposition, comprising:

[0033] a raw data calculation unit configured to establish an atmospheric transport model that takes into account aerosol particle size distribution and solubility, and to perform deposition simulation using the model to calculate cumulative deposition distribution data of different particle sizes;

[0034] a particle size distribution calculation unit configured to extract cumulative deposition results of different particle sizes, establish a particle size distribution solution equation group, and perform non-negative numerical solutions on the particle size distribution solution equation group;

[0035] The particle size distribution output unit is configured to output an aerosol particle size distribution result.

[0036] In a third aspect, the present invention provides a computer storage medium having computer-readable instructions stored thereon, wherein the computer-readable instructions can be executed by a processor to implement the method described.

[0037] In a fourth aspect, the present invention provides an electronic device, which includes at least a processor and a memory, wherein a computer program is stored in the memory, and when the processor runs the computer program, the computer program is executed to implement the method described.

[0038] The present invention has the following advantages due to the adoption of the above technical solution:

[0039] 1. This invention uses an atmospheric transport model that considers aerosol particle size distribution and solubility. It can simulate the unique behaviors of aerosols of different particle sizes and solubilities in the atmosphere during transport, diffusion, dry and wet deposition, and other meteorological processes, providing reasonable data support for solving particle size distribution problems.

[0040] 2. This invention uses a solution method based on deposition simulation, using an atmospheric transport model that accurately simulates cumulative deposition, extracting the cumulative deposition characteristics of aerosols of different particle sizes, and performing a non-negative numerical solution for the aerosol size distribution, thereby improving the accuracy of the particle size distribution results;

[0041] 3. The present invention uses a non-negative least squares algorithm to solve the aerosol particle size distribution based on the consistency between the deposition simulation results and the monitoring results, as well as the restriction that the sum of the percentages of aerosol components of each particle size is 1. The optimal solution of the aerosol particle size distribution is obtained and normalized to improve the rationality of the particle size distribution results.

[0042] In summary, the present invention can be widely applied to the calculation of particle size spectra of aerosols in pollutant leakage accidents or emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those skilled in the art. The accompanying drawings are only used to illustrate the preferred embodiment and are not to be considered as limitations of the present invention. Throughout the accompanying drawings, the same reference numerals are used to represent the same components.

[0044] In the attached figure:

[0045] Figure 1 This is a flow chart of a method for solving aerosol particle size composition based on deposition simulation according to an embodiment of the present invention;

[0046] Figure 2 This is a structural diagram of an aerosol particle size composition solution system based on deposition simulation according to an embodiment of the present invention;

[0047] Figure 3 Schematic diagram of the electronic device structure according to an embodiment of the present invention. DETAILED DESCRIPTION

[0048] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0049] The embodiment of the present invention provides a method for solving aerosol particle size composition based on deposition simulation, which includes establishing an atmospheric transmission model that takes into account aerosol particle size distribution and solubility, and can simulate the special performance behaviors of aerosols of different particle sizes and solubility in the atmosphere during meteorological processes such as transmission, diffusion, dry and wet deposition, and provide reasonable data support for solving particle size distribution. Deposition simulation is used for solution, and an atmospheric transmission model that accurately simulates cumulative deposition is used to extract the cumulative deposition characteristics of aerosols of different particle sizes, and a non-negative numerical solution is performed on the particle size distribution of aerosols to improve the accuracy of the particle size distribution results. A non-negative least squares algorithm is used to solve the set of equations. According to the compliance of the deposition simulation results and the monitoring, as well as the restriction that the sum of the percentages of aerosol components of each particle size is 1, a non-negative numerical solution is performed on the particle size distribution of aerosols to obtain the optimal solution of the aerosol particle size distribution and normalize it, thereby improving the rationality of the particle size distribution results.

[0050] Example 1

[0051] like Figure 1 As shown, embodiment 1 of the present invention provides a method for solving aerosol particle size composition based on deposition simulation, the method comprising the steps of:

[0052] S1. Establish an atmospheric transport model that takes into account aerosol particle size distribution and solubility, and use the model to perform deposition simulation to calculate the cumulative deposition distribution data of n particle sizes;

[0053] Based on the online coupled model WRF-Chem, an atmospheric transport model that considers aerosol particle size distribution and solubility is established. In the WRF-Chem model, cloud-in and cloud-below wet deposition schemes that consider particle size distribution and solubility are added. The specific steps include:

[0054] 1) Extracted variables include rainfall, temperature, humidity, and air pressure, and read variables include particle size and soluble aerosol ratio;

[0055] 2) Calculate the cloud water content. The cloud water content (LWC) refers to the mass of water contained in a unit of air mass in a unit cloud. It is calculated based on humidity, air pressure, temperature, and air molar mass.

[0056] 3) calculating the in-cloud and under-cloud wet deposition coefficients according to the cloud water content using formulas (1) and (2);

[0057] 4) Calculating the deposition amount based on the in-cloud and under-cloud wet deposition coefficients, calculating the deposition amount by the in-cloud and under-cloud wet deposition coefficients and the nuclide concentrations of the grids, and summing them in the vertical grid direction to obtain a two-dimensional spatial distribution of the deposition amount.

[0058] The atmospheric transport model considering aerosol particle size distribution and solubility calculates the cloud wet deposition coefficient Λ according to formula (1):

[0059]

[0060] Where Λ is the cloud wet deposition coefficient, LWC is the cloud water content, p0 is the rainfall intensity, Δz is the vertical grid height, and f inc is the activation coefficient, f inc Affected by aerosol particle size distribution and solubility

[0061] The atmospheric transport model considering aerosol particle size distribution and solubility calculates the cloud wet deposition coefficient Λ according to formula (2):

[0062]

[0063] g(r)=-0.15+0.32r-3×10 -2 r 2 +9.34×10 -4 r 3

[0064] f(p0)=2.7×10 -4 p0-3.618×10 -6 p02

[0065] Where r is the aerosol radius, p0 is the rainfall intensity, g(r) is a function related only to the particle size, and f(p0) is a function related only to the rainfall intensity.

[0066] S2. Extract the cumulative sedimentation distribution data of different particle sizes and establish a particle size distribution solution equation group, specifically including:

[0067] S2-1, extracting n-1 grid deposition data of n particle sizes, and establishing n-1 equations based on the deposition simulation results and the monitored compliance, wherein the n-1 equations and the equation whose particle size components add up to 1 form an equation system of n equations, wherein the equation system is a linear equation system;

[0068] The extracting of n-1 grid deposition data of n particle sizes includes randomly selecting n-1 grid data (a i ) and the n-1 grid data corresponding to the cumulative sedimentation monitoring (μ i ), and combined with the constraint that the particle size composition adds up to 1, the following system of equations consisting of n linear equations is formed:

[0069]

[0070] Where x is a vector consisting of the percentages of each particle size.

[0071] S3. performing non-negative numerical solutions to the particle size distribution equations to obtain aerosol particle size composition;

[0072] In step S3, the n equations are solved using a non-negative least squares (NNLS) algorithm, and the n particle sizes are normalized.

[0073] Specifically, based on the consistency between the deposition simulation results and the monitoring, as well as the restriction that the sum of the percentages of aerosol components of each particle size is 1, the aerosol particle size distribution is solved by non-negative numerical methods, the optimal solution of the aerosol particle size distribution is obtained and normalized to improve the rationality of the particle size distribution results.

[0074] S4. Output aerosol particle size composition.

[0075] The deposition results in this example represent the two-dimensional distribution of aerosol deposition within the computational domain. These results can be used to assess the consequences of pollutant leaks or releases, radioactive leaks, and other incidents, including the atmospheric dispersion of aerosols. They can also provide input for predicting aerosol migration in water or soil.

[0076] Example 2

[0077] This embodiment 2 provides a system for solving aerosol particle size composition based on deposition simulation. The system provided in this embodiment 2 can implement the method for solving aerosol particle size composition based on deposition simulation of embodiment 1, and the system can be implemented by software, hardware, or a combination of software and hardware. For the convenience of description, this embodiment is described by dividing the functions into various units and describing them separately. Of course, the functions of each unit can be implemented in the same or multiple software and / or hardware during implementation. For example, the system may include integrated or separate functional modules or functional units to perform the corresponding steps in each method of embodiment 1. Since the system of this embodiment is basically similar to the method embodiment, the description process of this embodiment is relatively simple, and the relevant parts can be referred to the method part of embodiment 1. The embodiment of the system for solving aerosol particle size composition based on deposition simulation provided by the present invention is merely illustrative.

[0078] Specifically, if Figure 2 As shown, the system for solving aerosol particle size composition based on deposition simulation provided in this embodiment includes:

[0079] a raw data calculation unit configured to establish an atmospheric transport model that takes into account aerosol particle size distribution and solubility, and to perform deposition simulation using the model to calculate cumulative deposition distribution data of different particle sizes;

[0080] a particle size distribution calculation unit configured to extract cumulative deposition results of different particle sizes, establish a particle size distribution solution equation group, and perform non-negative numerical solutions to the particle size distribution solution equation group;

[0081] The particle size distribution output unit is configured to output an aerosol particle size distribution result.

[0082] Example 3

[0083] The method for solving aerosol particle size composition based on deposition simulation in this embodiment 3 can be specifically implemented as a computer program product, which may include a computer-readable storage medium carrying computer-readable program instructions for executing the method for solving aerosol particle size composition based on deposition simulation described in this embodiment 1.

[0084] In some implementations, a computer-readable storage medium may be a tangible device that holds and stores instructions used by an instruction execution device. The computer-readable storage medium may be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof.

[0085] Example 4

[0086] This embodiment 4 provides an electronic device corresponding to the method for solving aerosol particle size composition based on deposition simulation provided in this embodiment 1. The electronic device can be an electronic device used for a client, such as a mobile phone, a laptop computer, a tablet computer, a desktop computer, etc., to execute the method of embodiment 1.

[0087] like Figure 3 As shown, the electronic device includes a processor, a memory, a communication interface and a communication bus, and the processor, the memory and the communication interface are connected through the communication bus to complete the communication between them. It can be understood by those skilled in the art that Figure 3 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computing device to which the solution of the present application is applied. The specific computing device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0088] In some implementations, the processor may be a central processing unit (CPU), a digital signal processor (DSP), or other general-purpose processors, which are not limited here.

[0089] In other implementations, a computer program that can be run on a processor is stored in the memory, and when the processor runs the computer program, it executes the method for solving the aerosol particle size composition based on deposition simulation provided in the first embodiment of the present invention. The computer program in the above-mentioned memory can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling an electronic device to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), optical disk and other media that can store program codes.

[0090] In some other implementations, the communication bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Component (EISA) bus, or the like.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for calculating aerosol particle size composition based on deposition simulation, characterized in that: Including steps: Establish an atmospheric transport model that takes into account aerosol particle size distribution and solubility, and use the model to simulate deposition and calculate the cumulative deposition distribution data of different particle sizes; Extract the cumulative sedimentation distribution data of different particle sizes and establish a particle size distribution solution equation set; Solving the particle size distribution equations with non-negative numerical values ​​to obtain the aerosol particle size composition; Output aerosol particle size composition; The calculation of the cumulative deposition distribution data of different particle sizes includes: Extracting variables, wherein the variables include rainfall, temperature, humidity, and air pressure; Calculate cloud water content using the variables; Calculating the wet deposition coefficients inside and below the cloud based on the cloud water content; Calculating the deposition amount based on the in-cloud and under-cloud wet deposition coefficients, specifically by calculating the in-cloud and under-cloud wet deposition coefficients and the nuclide concentrations of the grids, and summing them in the vertical grid direction to obtain a two-dimensional spatial distribution of the deposition amount; The extraction of the cumulative deposition distribution data of different particle sizes and the establishment of a particle size distribution solution equation group include: Extracting n-1 grid deposition data of n particle sizes, and establishing n-1 equations based on the deposition simulation results and the monitoring compliance, wherein the n-1 equations and the equation whose particle size components add up to 1 form an equation system of n equations, wherein the equation system is a linear equation system; The equation group is shown in formula (3): （3） Where x is the vector composed of the percentages of each particle size, are n-1 randomly selected grid data in the two-dimensional cumulative sedimentation distribution grid, n-1 grid data corresponding to cumulative sedimentation monitoring; The formula It means: [1,1,1, ...,1]*[x1,x2,x3,...,xn]' = 1, which is a horizontal quantity of all 1s multiplied by the vertical quantity x. The effect is to accumulate all the elements in x and finally equal 1.

2. The method for calculating aerosol particle size composition based on deposition simulation according to claim 1, characterized in that: Based on the online coupled model WRF-Chem, an atmospheric transport model considering aerosol particle size distribution and solubility was established.

3. The method for calculating aerosol particle size composition based on deposition simulation according to claim 1, characterized in that: The atmospheric transport model calculates the cloud wet deposition coefficient according to formula (1): （1） in, That is, the cloud wet deposition coefficient, LWC is the cloud water content, is the rainfall intensity, is the vertical grid height, is the activation coefficient, Affected by the particle size distribution and solubility of the aerosol.

4. The method for calculating aerosol particle size composition based on deposition simulation according to claim 1, characterized in that: The atmospheric transport model calculates the cloud wet deposition coefficient according to formula (2): （2） Where r is the aerosol radius, is the rainfall intensity, is a function related only to particle size, is a function related only to rainfall intensity.

5. The method for calculating aerosol particle size composition based on deposition simulation according to claim 1, characterized in that: The n equations are solved using a non-negative least squares algorithm and normalized to the n particle sizes.

6. A system for calculating aerosol particle size composition based on deposition simulation, characterized in that: include: a raw data calculation unit configured to establish an atmospheric transport model that takes into account aerosol particle size distribution and solubility, and to perform deposition simulation using the model to calculate cumulative deposition distribution data of different particle sizes; a particle size distribution calculation unit configured to extract cumulative deposition results of different particle sizes, establish a particle size distribution solution equation group, perform non-negative numerical solutions on the particle size distribution solution equation group, and obtain an aerosol particle size distribution result; A particle size distribution output unit is configured to output an aerosol particle size distribution result; The calculation of the cumulative deposition distribution data of different particle sizes includes: Extracting variables, wherein the variables include rainfall, temperature, humidity, and air pressure; Calculate cloud water content using the variables; Calculating the wet deposition coefficients inside and below the cloud based on the cloud water content; Calculating the deposition amount based on the in-cloud and under-cloud wet deposition coefficients, specifically by calculating the in-cloud and under-cloud wet deposition coefficients and the nuclide concentrations of the grids, and summing them in the vertical grid direction to obtain a two-dimensional spatial distribution of the deposition amount; The extraction of the cumulative deposition distribution data of different particle sizes and the establishment of a particle size distribution solution equation group include: Extracting n-1 grid deposition data of n particle sizes, and establishing n-1 equations based on the deposition simulation results and the monitoring compliance, wherein the n-1 equations and the equation whose particle size components add up to 1 form an equation system of n equations, wherein the equation system is a linear equation system; The equation group is shown in formula (3): （3） Where x is the vector composed of the percentages of each particle size, are n-1 randomly selected grid data in the two-dimensional cumulative sedimentation distribution grid, n-1 grid data corresponding to cumulative sedimentation monitoring; The formula It means: [1,1,1, ...,1]*[x1,x2,x3,...,xn]' = 1, which is a horizontal quantity of all 1s multiplied by the vertical quantity x. The effect is to accumulate all the elements in x and finally equal 1.

7. A computer storage medium, characterized in that Computer-readable instructions are stored thereon, and the computer-readable instructions can be executed by a processor to implement the method according to any one of claims 1 to 5.

8. An electronic device comprising at least a processor and a memory, wherein a computer program is stored in the memory, wherein: When the processor runs the computer program, the computer program is executed to implement the method according to any one of claims 1 to 5.

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