Method of determining the deposition rate of an aerosol system

Abstract

Embodiments of the present application relate to the technical field of reactor accident analysis, and particularly relate to a method for determining deposition rate of aerosol system, comprising: S1, determining the gas space parameters of the aerosol system under a predetermined working condition, the gas parameters under the predetermined working condition, and the physical property parameters of each type of aerosol in the aerosol system; S2, determining the deposition mode of the aerosol system under the predetermined working condition; S3, determining the deposition speed of all aerosols in the aerosol system according to the deposition mode determined in S2 and the gas parameters under the predetermined working condition and the physical property parameters of each type of aerosol in the aerosol system determined in S1; and S4, determining the deposition rate of the aerosol system according to the deposition speed determined in S3 and the gas space parameters determined in S1. The method of the embodiments of the present application can realize the research on the deposition behavior of the aerosol system composed of two aerosols of different components, so as to make up for the deficiency of the current aerosol behavior research and analysis model.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of reactor accident analysis, and in particular to a method for determining deposition rate of aerosol system. BACKGROUND

[0002] The statements herein are merely provided to give general background information on the present application, and do not necessarily constitute the prior art.

[0003] When a severe accident occurs in a nuclear power plant, radioactive substances are mainly released in the form of fission gas and aerosol. The fission gas can include Kr, Xe and other gases, and the aerosol can include I, Br, Cs, Rb, Te, Sb, Se, Ba, Sr and other nuclides. Aerosol refers to liquid or solid particles suspended in gas, and the particle size range is generally 0.1 μm to 100 μm.

[0004] The release and migration of aerosol are mainly affected by the behavior of the particulate matter itself and the environmental conditions of the severe accident. In the severe accident analysis model, the deposition behavior of aerosol of a single component is generally modeled, but due to the coagulation behavior of the particulate matter, the particulate matter of different components can also be aggregated together due to coagulation. The deposition behavior of the aerosol system composed of particulate matter of different components is not considered in the existing aerosol behavior analysis model, and therefore the existing aerosol behavior analysis model is not applicable. SUMMARY

[0005] A brief summary of the present application is presented in the following to provide a basic understanding of some aspects of the present application. It should be understood that this summary is not an extensive overview of the present application. It is not intended to identify key or critical elements of the present application, nor is it intended to limit the scope of the present application. Its purpose is merely to present some concepts in a simplified form as a prelude to the more detailed description of a later discussion.

[0006] The embodiment of the present application provides a method for determining the deposition rate of an aerosol system, the aerosol system comprising a first aerosol and a second aerosol, which comprises the following steps: S1, determining the gas space parameters of the aerosol system under a predetermined working condition, the gas parameters under the predetermined working condition, and the physical property parameters of each type of aerosol in the aerosol system; S2, determining the deposition mode of the aerosol under the predetermined working condition; S3, determining the deposition speed of all aerosols in the aerosol system according to the deposition mode determined in the step S2 and the gas parameters under the predetermined working condition and the physical property parameters of each type of aerosol in the aerosol system determined in the step S1; S4, determining the deposition rate of the aerosol system according to the deposition speed determined in the step S3 and the gas space parameters determined in the step S1; wherein the gas space parameters comprise length, width and height values of the gas space, the gas parameters comprise gas humidity and gas temperature, and the physical property parameters comprise density and particle size range of the aerosol.

[0007] The method provided by the embodiment of the present application can determine the deposition rate of the aerosol system by determining the gas space parameters of the aerosol system under a predetermined working condition and the physical property parameters of each type of aerosol in the aerosol system, so that the deposition behavior of the aerosol system composed of two aerosols of different components can be researched, and the deficiency of the current aerosol behavior research and analysis model can be made up.

[0008] These and other advantages of the present application will no doubt become apparent to those of ordinary skill in the art after having read the following detailed description of the preferred embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0009] In order to further illustrate the above and other advantages and features of the present application, the specific embodiments of the present application are further described in detail below with reference to the accompanying drawings. The drawings, together with the following detailed description, are incorporated in and constitute a part of this specification. Elements having the same function and structure are denoted by the same reference signs. It should be understood that these drawings only describe typical examples of the present application and should not be regarded as limiting the scope of the present application.

[0010] Figure 1 is a schematic diagram of an aerosol system according to an embodiment of the present application;

[0011] Figure 2 is a schematic flow chart of a method for determining the deposition rate of an aerosol system according to an embodiment of the present application;

[0012] Figure 3 is a schematic diagram of aerosol gravitational settling according to an embodiment of the present application;

[0013] Figure 4 is a schematic diagram of aerosol Brownian diffusion according to an embodiment of the present application.

[0014] It should be noted that the accompanying drawings are included to provide a further understanding of the present application and are incorporated in and constitute a part of this specification, illustrate embodiments of the present application and together with the description serve to explain the principles of the present application. In the drawings:

[0015] BRIEF DESCRIPTION OF DRAWINGS

[0016] 10, aerosol system; 101, first aerosol; 102, second aerosol;

[0017] 301, third aerosol; 302, first thermal member;

[0018] 401, fourth aerosol; 402, second thermal member. DETAILED DESCRIPTION

[0019] Embodiments of the present application will be described herein below with reference to the drawings. In the description, all the features of the practical embodiments are not described in order to make the present application clear and brief. It should be appreciated that, in the development of any such actual embodiment, numerous implementation-specific decisions must be made in order to achieve the developer's specific goals, such as compliance with system- and business-related constraints, which will vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of those of ordinary skill in the art having the benefit of this disclosure.

[0020] It should also be noted that, in the drawings, only the structures and / or processing steps closely related to the solution according to the present application are shown, and other details not closely related to the present application are omitted in order not to obscure the present application with unnecessary details.

[0021] It should be noted that the technical or scientific terms used in the present application should be understood as the usual meaning understood by those skilled in the art, unless otherwise defined.

[0022] In the description of embodiments of the present application, the meaning of "a plurality of" is at least two, for example two, three, etc., unless otherwise explicitly specified.

[0023] In the current aerosol behavior analysis model, the main principle is to use mathematical methods to describe the general dynamic equation (GDE) based on the Smoluchowski mean field theory. The GDE equation is a number density function control equation with the volume or mass of the aerosol as the internal variable, and the general variable symbol is written as n ( v , t ), wherein, n represents the number of aerosols, and the unit is piece.v represents the volume size of the aerosol, and the unit is m 3 ; t represents time, and the unit is s. The particle system described by the GDE equation is generally only distinguished by the volume or mass size, and is not distinguished in terms of material properties.

[0024] In the related art, the aerosol behavior analysis model in the field of nuclear engineering is mostly established on the basis of solving the zero-dimensional single-variable GDE equation by using a numerical method. However, in actual situations, due to the condensation / aggregation behaviors between aerosols, the aerosol system may be an agglomerate composed of aerosols of different components. The existing GDE equation cannot be applied to the application scenario of describing the aerosol behavior of the agglomerate composed of particles of different components.

[0025] To solve the above technical problems, embodiments of the present application provide a method for determining the deposition rate of an aerosol system. Figure 1 is a schematic diagram of an aerosol system according to an embodiment of the present application, as Figure 1 shown, the aerosol system 10 can include a first aerosol 101 and a second aerosol 102.

[0026] In some embodiments, the aerosol system 10 is a mixture composed of the first aerosol 101 and the second aerosol 102 having different properties (for example, different densities).

[0027] In some embodiments, the mass of the first aerosol 101 and the mass of the second aerosol 102 satisfy the following expressions (1) and (2), respectively:

[0028] (1);

[0029] (2).

[0030] wherein, represents the mass of the first aerosol 101; represents the volume of the first aerosol 101; represents the density of the first aerosol 101; represents the mass of the second aerosol 102; represents the volume of the second aerosol 102; represents the density of the second aerosol 102.

[0031] In some embodiments, the mass percentage and the volume percentage of the first aerosol 101 in the aerosol system 10 satisfy the following expressions (3) to (6):

[0032] (3);

[0033] (4);

[0034] (5);

[0035] (6).

[0036] wherein, represents the mass of the aerosol system 10; represents the volume of the aerosol system 10; represents the density of the aerosol system 10; represents the mass percentage of the first aerosol 101 in the aerosol system 10; represents the volume percentage of the first aerosol 101 in the aerosol system 10.

[0037] Figure 2 is a schematic flow chart of a method for determining the deposition rate of an aerosol system according to an embodiment of the present application, as shown in FIG. 1, the method can include the following steps S1 to S4. Figure 2

[0038] S1, determining the gas space parameters of the aerosol system 10 under a predetermined working condition, the gas parameters under the predetermined working condition, and the physical property parameters of each type of aerosol in the aerosol system 10, wherein the gas space parameters include the length value, width value and height value of the gas space, the gas parameters include the gas humidity and gas temperature, and the physical property parameters include the density and particle size range of the aerosol.

[0039] S2, determining the deposition mode of the aerosol system under the predetermined working condition.

[0040] S3, determining the deposition speed of all aerosols in the aerosol system 10 according to the deposition mode determined in step S2 and the gas parameters under the predetermined working condition and the physical property parameters of each type of aerosol in the aerosol system 10 determined in step S1.

[0041] S4, determining the deposition rate of the aerosol system 10 according to the deposition speed determined in step S3 and the gas space parameters determined in step S1.

[0042] The method provided by the embodiments of the present application can determine the deposition rate of the aerosol system 10 by determining the gas space parameters of the aerosol system 10 under a predetermined working condition, the physical property parameters of each type of aerosol in the aerosol system 10, and the deposition mode of the aerosol system, which can realize the research on the deposition behavior of the aerosol system 10 composed of two aerosols of different components, so as to make up for the deficiency of the current aerosol behavior research and analysis model.

[0043] In some embodiments, the deposition mode of the aerosol can include gravitational settling​S ed Brownian diffusion D if thermophoresis T ph diffusiophoresis D ph , etc.

[0044] In some embodiments, the particle size of each aerosol in the aerosol system 10 is in the range of 0.01-10 μm.

[0045] In some embodiments, in the S4 step, the deposition rate of the aerosol system 10 and the deposition speed, the gas space parameters satisfy the following first expression (7):

[0046]

[0047] (7).

[0048] wherein, denotes the moment of the deposition system, and satisfies the following expression (8):

[0049] (8).

[0050] wherein, k denotes the Taylor expansion order of the aerosol system 10, k =0, 1, 2, 3…, and k is an integer; l denotes the Taylor expansion order of the first aerosol 101, l =0, 1, 2, 3…, and l is an integer; V denotes the volume of the gas space in which the aerosol system 10 is located; A Sed denotes the deposition area of the aerosol system under the gravitational sedimentation deposition mode; A Dif denotes the deposition area of the aerosol system under the Brownian diffusion deposition mode; A Tph denotes the deposition area of the aerosol system under the thermophoresis deposition mode; A Dph denotes the deposition area of the aerosol system under the diffusiophoresis deposition mode; v Sed denotes the deposition speed of the aerosol system on the deposition area corresponding to the gravitational sedimentation deposition mode; v Dif denotes the deposition speed of the aerosol system on the deposition area corresponding to the Brownian diffusion deposition mode; v TphThis indicates the deposition rate of the aerosol system over the deposition area corresponding to the thermophoretic deposition method; v Dph This represents the deposition rate of the aerosol system over the deposition area corresponding to the diffusion-coated deposition method; u 1 represents the center point of the Taylor expansion of aerosol system 10; u 2 represents the center point of the Taylor expansion of the first aerosol 101; , , , , and These represent different initial moments.

[0051] The embodiments of this application determine the deposition rate of the aerosol system 10 through the first expression (7), which is relatively efficient and accurate.

[0052] In some embodiments, for the number density function of two-component aerosols An expression of the following form (9) can be constructed:

[0053] (9).

[0054] in, k This represents the Taylor expansion order of aerosol system 10. k =0,1,2,3… and k It is an integer; l This represents the Taylor expansion order of the first aerosol 101. l =0,1,2,3… and l It is an integer.

[0055] For expression (9), by... This can be addressed by removing the integral form. (Regarding internal variables...) and The expression containing this can be subjected to Taylor expansion. u 1 and u 2, which satisfies the following expression (10):

[0056] (10).

[0057] in, u 1 represents The center point of the Taylor expansion is typically taken as the average volume of the aerosol system, i.e. ; u 2 indicates The center point of the Taylor expansion is usually taken as the average volume of the first aerosol 101, i.e. .

[0058] In some embodiments, the expression (10) is brought into the expression (9), and the above expression (8) can be obtained.

[0059] In some embodiments, according to the principle of the two-component aerosol Taylor expansion moment method, the evolution expressions (11) of the six initial moments , , , , and can be obtained by solving the following equation group:

[0060] (11).

[0061] wherein, is a dimensionless moment, ; is a constant related to the properties of the aerosol, , is the Boltzmann constant, is the temperature, in K, is the gas viscosity, in Pa∙s; t is time.

[0062] In some embodiments, by solving the moment equation group corresponding to the expression (11), the results of the six initial moments can be obtained, and then the evolution law of the moment model of any order can be obtained by bringing the expression (8) as needed, and the migration of the aerosol can be calculated according to the physical model involved in the aerosol behavior analysis model. Compared with the traditional partition method, the number of equations to be solved in the method of the embodiments of the present application is less, which is conducive to improving the calculation efficiency.

[0063] In some embodiments, for the four deposition behaviors of the aerosol, the deposition rate of the aerosol system 10 satisfies the following expression (12):

[0064] (12).

[0065] wherein, is the deposition rate of the aerosol system 10, in pieces / s; is the volume of the gas space where the aerosol system 10 is located, in m 3 ; A Sed is the deposition area of the aerosol system under the gravitational settling deposition mode, in m 2 ; A Dif is the deposition area of the aerosol system under the Brownian diffusion deposition mode; ATph This represents the deposition area of ​​the aerosol system under thermophoretic deposition. A Dph This represents the deposition area of ​​the aerosol system under the diffusion-coated deposition method; v Sed This represents the deposition rate of an aerosol system over the depositional area corresponding to gravity sedimentation, expressed in m / s. v Dif This represents the deposition rate of the aerosol system over the deposition area corresponding to Brownian diffusion deposition. v Tph This indicates the deposition rate of the aerosol system over the deposition area corresponding to the thermophoretic deposition method; v Dph This indicates the deposition rate of the aerosol system over the deposition area corresponding to the diffusion-electrophoretic deposition method.

[0066] By transforming expression (12) into a moment equation, we can obtain the first expression (7) above:

[0067]

[0068]

[0069] (7).

[0070] The inventors of this application have discovered that, for the four mechanisms leading to aerosol deposition (gravitational sedimentation, Brownian diffusion, thermophoresis, and diffraction), gravity sedimentation is related to aerosol density, Brownian diffusion is only related to aerosol volume, while the aerosol deposition behavior caused by thermophoresis and diffraction is unrelated to aerosol properties. Therefore, the following embodiments will describe in detail the two deposition mechanisms of aerosol gravity sedimentation and Brownian diffusion.

[0071] In some embodiments, in step S3, the deposition method is gravity sedimentation deposition. Under gravity sedimentation deposition, the deposition rate of all aerosols in aerosol system 10 and the gas parameters and physical property parameters of each type of aerosol in aerosol system 10 under the predetermined operating conditions determined in step S1 satisfy the following second expression (13):

[0072] (13).

[0073] in, This represents the deposition rate of all aerosols in aerosol system 10 under gravity sedimentation deposition, expressed in m / s. This indicates the density of the first aerosol 101. This indicates the density of the second aerosol 102; This indicates the volume of the first aerosol 101. This indicates the volume of aerosol system 10; Represents gravitational acceleration; For Cunningham slip correction factor, representing the correction factor related to gas temperature, pressure, and aerosol particle size; Indicates aerodynamic viscosity; This indicates the shape parameters of the aerosol system 10.

[0074] The embodiments of this application can calculate the deposition rate of the aerosol system 10 under gravity sedimentation deposition mode relatively accurately and quickly through the above expression (13), with relatively high reliability and efficiency.

[0075] In some embodiments, Figure 3 This is a schematic diagram of aerosol gravity settling according to an embodiment of this application, as shown below. Figure 3 As shown, if the third aerosol 301 is composed of a single-component aerosol, then the deposition rate of the aerosol on the surface of the first thermal member 302 due to gravity settling satisfies the following expression (14):

[0076] (14).

[0077] in, The deposition rate of the third aerosol 301, a single component, under gravity sedimentation deposition is expressed in m / s. The number density of the third aerosol 301, representing the single component, is expressed in kg / m³. 3 ; This represents the acceleration due to gravity, with units of m / s². 2 ; The diameter of the third aerosol 301 of this single component is indicated in meters (m). Cunningham slip correction factor, representing the correction factor related to gas temperature, pressure, and aerosol particle size; This represents aerodynamic viscosity, measured in Pa·s. The shape parameters of the third aerosol 301 of this single component are indicated.

[0078] It is understandable that aerosol systems composed of aerosol particles with different components can be treated as a single particulate matter in aerosol behavior analysis models. Therefore, Figure 3 and in the following embodiments Figure 4 Each aerosol in the equation can be considered as an aerosol system.

[0079] In some embodiments, the aerosol deposition rate due to gravity settling is related to the aerosol density. For the aerosol system 10 in this embodiment (it can be understood that...),Figure 3 In the middle, the third aerosol 301 can also be regarded as an aerosol system composed of multi-component aerosols. The Taylor expansion moment method model equation for aerosol deposition caused by gravity sedimentation can be established, which satisfies the following expression (15):

[0080] (15).

[0081] To facilitate the execution of the Taylor expansion moment method, the above expression (14) can be modified based on expression (11) to obtain the following expression (16):

[0082]

[0083]

[0084] (16).

[0085] in, .

[0086] In some embodiments, the second expression (13) described above can be determined by expression (16).

[0087] In some embodiments, in step S4, the deposition rate of the aerosol system 10 and the deposition velocity, as well as the gas space parameters, satisfy the following third expression (17):

[0088] (17).

[0089] in, This represents the deposition area of ​​aerosol system 10 under gravity sedimentation, where the fractional moment... and Satisfy the following expression (18):

[0090] (18).

[0091] in, .

[0092] In some embodiments, the third expression (17) can be closed using the first three moments of the deposition system.

[0093] In some embodiments, in step S3, the deposition method is Brownian diffusion deposition. Under Brownian diffusion deposition, the deposition rate of aerosol system 10 and the gas parameters and physical properties of various types of aerosols in aerosol system 10 under predetermined operating conditions determined in step S1 satisfy the following fourth expression (19):

[0094] (19).

[0095] in, This represents the deposition rate of all aerosols in aerosol system 10 under Brownian diffusion deposition. This represents Boltzmann's constant. Indicates the temperature of the air space. Indicates aerodynamic viscosity. Indicates the thickness of the diffusion boundary layer. Indicates the shape parameters of aerosols. This indicates the volume of aerosol system 10. A correction factor indicating the degree of influence of gas molecule slippage on the flow. This represents the mean free path of gas molecules.

[0096] The embodiments of this application can calculate the deposition rate of the aerosol system 10 under Brownian diffusion deposition mode relatively accurately and quickly through the above expression (19), with high reliability and efficiency.

[0097] In some embodiments, Figure 4 This is a schematic diagram of aerosol Brownian diffusion according to an embodiment of this application, as shown below. Figure 4 As shown, if the fourth aerosol 401 is composed of a single-component aerosol, then its deposition rate on the surface of the second thermal member 402 due to Brownian diffusion satisfies the following expression (20):

[0098] (20).

[0099] in, This indicates the Brownian diffusion deposition rate, expressed in m / s. This represents the Boltzmann constant, which is 1.38 × 10⁻⁶. -23 J / K; This indicates the temperature of the air-filled space, expressed in Kelvin (K). This represents the thickness of the diffusion boundary layer, with a default value of 1×10⁻⁶. -5 m.

[0100] To facilitate the application of the Taylor expansion method to expression (20), expression (20) can be modified into the following expression (21):

[0101]

[0102]

[0103] (twenty one).

[0104] in, , .

[0105] In some embodiments, the fourth aerosol 401 is extended from a single-component aerosol to a two-component aerosol (i.e., the aerosol system 10 of this application embodiment), and the deposition rate, deposition velocity, and gas space parameters of the aerosol system 10 satisfy the following fifth expression (22):

[0106] (twenty two).

[0107] in, This represents the deposition area of ​​aerosol system 10 under Brownian diffusion deposition. Represents the aerosol volume, where the fractional moments involved in Brownian diffusion deposition are... and Satisfy the following expression (23):

[0108] (twenty three).

[0109] In some embodiments, the fifth expression (22) is enclosed, and the enclosed method is similar to that of the third expression (17), which will not be described again here.

[0110] Regarding the embodiments of this application, it should also be noted that, without conflict, the embodiments of this application and the features in the embodiments can be combined with each other to obtain new embodiments.

[0111] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. The scope of protection of this application shall be determined by the scope of the claims.

Claims

1. A method for determining the deposition rate of an aerosol system, said aerosol system comprising a first aerosol and a second aerosol, characterized in that, It includes the following steps: S1. Determine the gas space parameters of the aerosol system under the predetermined operating conditions, the gas parameters under the predetermined operating conditions, and the physical property parameters of each type of aerosol in the aerosol system. S2. Determine the deposition method of the aerosol system under the predetermined operating conditions; S3. Based on the deposition method determined in step S2 and the gas parameters under the predetermined working conditions determined in step S1, as well as the physical property parameters of each type of aerosol in the aerosol system, determine the deposition rate of all aerosols in the aerosol system. S4. Determine the deposition rate of the aerosol system based on the deposition rate determined in step S3 and the gas space parameters determined in step S1. The gas space parameters include the length, width, and height of the gas space; the gas parameters include gas humidity and gas temperature; and the physical property parameters include the density and particle size range of the aerosol.

2. The method according to claim 1, characterized in that, In step S4, the deposition rate of the aerosol system and the deposition velocity, along with the gas space parameters, satisfy the following first expression: ； in, The moments representing the deposition system satisfy the following expression: ； in, k This represents the Taylor expansion order of the aerosol system. k =0,1,2,3… and k It is an integer; l This represents the Taylor expansion order of the first aerosol. l =0,1,2,3… and l It is an integer; t Indicates time; V This indicates the volume of the gas space containing the aerosol system; A Sed This represents the deposition area of ​​the aerosol system under gravity sedimentation deposition. A Dif This represents the deposition area of ​​the aerosol system under Brownian diffusion deposition. A Tph This represents the deposition area of ​​the aerosol system under thermophoretic deposition. A Dph This represents the deposition area of ​​the aerosol system under the diffusion-coated deposition method; v Sed This indicates the deposition rate of the aerosol system over the deposition area corresponding to the gravity sedimentation deposition method; v Dif This represents the deposition rate of the aerosol system over the deposition area corresponding to the Brownian diffusion deposition method; v Tph This indicates the deposition rate of the aerosol system over the deposition area corresponding to the thermophoretic deposition method; v Dph This indicates the deposition rate of the aerosol system over the deposition area corresponding to the diffusion-coated deposition method; u 1 represents the center point of the Taylor expansion of the aerosol system; u 2 represents the center point of the Taylor expansion of the first aerosol; , , , and These represent different initial moments.

3. The method according to claim 2, characterized in that, In step S3, the deposition method is gravity sedimentation deposition. Under the gravity sedimentation deposition method, the deposition rate of all aerosols in the aerosol system, the gas parameters under the predetermined operating conditions determined in step S1, and the physical properties of each type of aerosol in the aerosol system satisfy the following second expression: ； in, This represents the deposition rate of all aerosols in the aerosol system under the gravity sedimentation deposition method. This represents the density of the first aerosol. This indicates the density of the second aerosol. This represents the volume of the first aerosol. This indicates the volume of the aerosol system. Represents gravitational acceleration. This represents the Cunningham slip correction factor. Indicates aerodynamic viscosity. This represents the shape parameters of the aerosol system.

4. The method according to claim 3, characterized in that, In step S4, the deposition rate of the aerosol system and the deposition velocity, along with the gas space parameters, satisfy the following third expression: ； in, The area of ​​the aerosol system under gravity sedimentation deposition represents the deposition area, where the fractional moment is... and Satisfy the following expression: ； in, .

5. The method according to claim 4, characterized in that, The third expression is enclosed.

6. The method according to claim 2, characterized in that, In step S3, the deposition method is Brownian diffusion deposition. Under this Brownian diffusion deposition method, the deposition rate of all aerosols in the aerosol system and the gas parameters under the predetermined operating conditions determined in step S1, as well as the physical property parameters of each type of aerosol in the aerosol system, satisfy the following fourth expression: ； in, This represents the deposition rate of all aerosols in the aerosol system under the Brownian diffusion deposition method. This represents Boltzmann's constant. Indicates the temperature of the air space. Indicates aerodynamic viscosity. Indicates the thickness of the diffusion boundary layer. Indicates the shape parameters of aerosols. This indicates the volume of the aerosol system. A correction factor indicating the degree of influence of gas molecule slippage on the flow. This represents the mean free path of gas molecules.

7. The method according to claim 6, characterized in that, In step S4, the deposition rate of the aerosol system and the deposition velocity, along with the gas space parameters, satisfy the following fifth expression: ； in, This represents the deposition area of ​​the aerosol system under the Brownian diffusion deposition method. Represents the aerosol volume, where the fractional moments involved in Brownian diffusion deposition are... and Satisfy the following expression: 。 8. The method according to claim 7, characterized in that, The fifth expression is enclosed.

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