Mass spectrometer ion source transmission efficiency characteristic simulation analysis method based on multi-physics field coupling

Abstract

The invention discloses a mass spectrometer ion source transmission efficiency characteristic simulation analysis method based on multi-physics field coupling, and relates to the technical field of mass spectrometry, and the method comprises the steps: carrying out discretization processing through a grid division method, and generating a grid model suitable for multi-physics field simulation; on the basis of the grid model, ions generated by electrospray are equivalent to particles by coupling a turbulence model, a dispersed phase model and a magnetohydrodynamic model, and a multi-physical field simulation model is constructed; obtaining internal flow field distribution, electric field intensity distribution and ion trajectory data of the mass spectrometer ion source through a numerical calculation method according to the multi-physical field simulation model and preset boundary conditions, and calculating ion transmission efficiency data according to the flow field distribution, the electric field intensity distribution and the ion trajectory data; and generating a transmission efficiency characteristic curve of the mass spectrometer ion source prototype through a parameterized simulation method according to the ion transmission efficiency data. The method is used for realizing accurate simulation of the internal physical process of the ion source.

Description

Technical Field

[0001] The present invention relates to the technical field of mass spectrometry analysis, and in particular to a method for simulating and analyzing transmission efficiency characteristics of an ion source of a mass spectrometer based on multi-physical field coupling. Background Art

[0002] In modern scientific research and analytical testing, the mass spectrometer is a critical piece of equipment, and the performance of its ion source plays a decisive role in overall analytical accuracy. The ion source is responsible for ionizing the sample and transmitting ions to the mass analyzer. This process involves complex multi-physics interactions, such as flow fields, electric fields, and the interaction of discrete phases.

[0003] Currently, research on mass spectrometer ion sources faces numerous challenges. For one thing, the lack of comprehensive and accurate coupled analysis of multiple physical fields when simulating the physical processes within the ion source results in significant deviations from actual predictions of ion trajectories and transmission efficiency. Traditional research methods often consider either the flow field or the electric field in isolation, ignoring the strong interplay between the two. For example, when analyzing ion motion in an electric field, the interference of flow field drag on the ion path is not fully considered, resulting in distorted simulation results.

[0004] On the other hand, existing technologies have significant shortcomings when dealing with the complex process of ion generation in electrospray ionization sources. During the electrospray process, the initial droplets undergo solvent evaporation and Coulomb explosion to form smaller droplets that ultimately ionize. However, traditional methods struggle to accurately describe this dynamic process. The lack of accuracy in estimating key parameters such as the initial droplet radius, the number of small droplets after fragmentation, and the charge they carry makes it impossible to accurately simulate ion generation and transmission, severely impacting the evaluation and optimization of ion source performance. Summary of the Invention

[0005] The present invention aims to solve at least one of the above problems. The present invention provides a simulation and analysis method for the transmission efficiency characteristics of a mass spectrometer ion source based on multi-physical field coupling. By constructing a multi-physical field coupling simulation model of a mass spectrometer ion source, the interaction between the flow field, electric field and discrete phase is fully considered to achieve accurate simulation of the physical process inside the ion source.

[0006] To achieve the above object, the present invention provides a method for simulating and analyzing the transmission efficiency characteristics of an ion source of a mass spectrometer, comprising the following steps:

[0007] Obtaining structural parameter data of a mass spectrometer ion source prototype to be simulated and analyzed;

[0008] Constructing a three-dimensional geometric model of the mass spectrometer ion source prototype using three-dimensional modeling software according to the structural parameter data;

[0009] Based on the three-dimensional geometric model, a discretization process is performed using a meshing method to generate a mesh model suitable for multi-physics field simulation;

[0010] Based on the grid model, by coupling the turbulence model, discrete phase model and magnetohydrodynamic model, the ions generated by electrospray are equivalent to particles, and a multi-physics field simulation model is constructed;

[0011] According to the multi-physics field simulation model and preset boundary conditions, the internal flow field distribution, electric field intensity distribution and ion trajectory data of the mass spectrometer ion source are obtained by numerical calculation method, and the ion transmission efficiency data is calculated based on the flow field distribution, electric field intensity distribution and ion trajectory data;

[0012] According to the ion transmission efficiency data, a transmission efficiency characteristic curve of the mass spectrometer ion source prototype is generated by a parameterized simulation method.

[0013] The mass spectrometer ion source transmission efficiency characteristic simulation analysis method described above, further, the mass spectrometer ion source prototype specifically includes:

[0014] ion source chamber;

[0015] an atomizing gas inlet, a drying gas inlet and a curtain gas inlet connected to the ion source cavity;

[0016] An ion source exhaust chamber connected to the ion source chamber, wherein the ion source exhaust chamber is connected to an exhaust port;

[0017] A sampling cone is located in the center of the ion source cavity.

[0018] In the above-mentioned simulation analysis method for the transmission efficiency characteristics of the mass spectrometer ion source, further, the coupled turbulence model is determined according to the following formula:

[0019] Assuming that the flow is incompressible, the K equation and ε equation are used to describe the dynamic characteristics of the turbulent field of particles:

[0020]

[0021] Where, It represents the rate of change of the turbulent kinetic energy k of unit volume fluid per unit time, represents the convection term of turbulent kinetic energy k, u i represents the macroscopic velocity of the fluid, is the diffusion term of turbulent kinetic energy k, μ is the molecular viscosity coefficient, μ t is the turbulent viscosity, σ k is the turbulent kinetic energy diffusion coefficient; G krepresents the generation term of turbulent kinetic energy k caused by the mean velocity gradient, -ρε represents the dissipation term of turbulent kinetic energy, ρ is the fluid density, and ε is the turbulent kinetic energy dissipation rate;

[0022] represents the rate of change of turbulent kinetic energy dissipation rate ε with time, The convective term representing the turbulent kinetic energy dissipation rate ε, represents the effect of the turbulent kinetic energy generated by the mean velocity gradient on the turbulent kinetic energy dissipation rate, represents the effect of the turbulent kinetic energy generated by the mean velocity gradient on the turbulent kinetic energy dissipation rate; is the dissipation term of the turbulent kinetic energy dissipation rate ε, C 1ε and C 2ε and C μ All are empirical constants.

[0023] In the above-mentioned simulation analysis method for the transmission efficiency characteristics of the mass spectrometer ion source, the magnetohydrodynamic model is further determined according to the following formula:

[0024] Magnetohydrodynamic model based on electric potential method:

[0025]

[0026] represents the electric field strength, and are scalar electric potential and vector electric potential respectively.

[0027] In the above-mentioned simulation analysis method for the transmission efficiency characteristics of the mass spectrometer ion source, further, the discrete phase model is determined according to the following formula:

[0028] The equation for the force acting on the particle is:

[0029]

[0030] Among them, m p is the particle mass, is the fluid velocity, is the particle velocity, ρ is the fluid density, ρ p is the particle density, τ r is the relaxation time, q is the particle charge, is the electric field strength, represents the fluid drag force on the particle, represents gravity, Represents the electric field force.

[0031] As described above, the simulation and analysis method of the mass spectrometer ion source transmission efficiency characteristics, further, the ion transmission efficiency is determined by statistically obtaining the number of ion particles entering the sampling cone based on the flow field distribution, electric field intensity distribution and ion trajectory data, and is determined based on the ratio of the number of ion particles entering the sampling cone to the preset total number of particles.

[0032] The mass spectrometer ion source transmission efficiency characteristic simulation analysis method as described above further includes preset boundary conditions including flow field simulation boundary conditions, electric field simulation boundary conditions and discrete phase boundary conditions.

[0033] The mass spectrometer ion source transmission efficiency characteristic simulation analysis method described above further adjusts the spray voltage, atomizing gas flow rate, drying gas flow rate, curtain gas flow rate and exhaust pressure through a single variable control method to generate a quantitative curve of the transmission efficiency as a function of each parameter.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] This paper constructs a multi-physics coupled simulation model of the mass spectrometer ion source, comprehensively considering the interactions between the flow field, electric field, and discrete phases to achieve precise simulation of the physical processes within the ion source. By utilizing user-defined functions and scalars, the model effectively couples the flow field drag and electric field forces, accurately estimating key parameters in the electrospray ionization process. Based on this model, the ion source transmission efficiency is accurately calculated, providing solid theoretical support for the optimized design of the mass spectrometer ion source and fundamentally improving the analytical performance of the mass spectrometer. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 Schematic diagram of the flow of a method for simulating and analyzing the transmission efficiency characteristics of an ion source of a mass spectrometer in an embodiment of the present invention;

[0038] Figure 2 Schematic diagram of the structure of the mass spectrometer ion source prototype in an embodiment of the present invention;

[0039] Figure 3 A cross-sectional potential distribution diagram of an ion source of a mass spectrometer according to an embodiment of the present invention;

[0040] Figure 4 This is a flow field distribution diagram in the ion source of a mass spectrometer according to an embodiment of the present invention;

[0041] Figure 5ion trajectory diagram in the absence of an electric field in the ion source of a mass spectrometer according to an embodiment of the present invention;

[0042] Figure 6 This is a diagram of ion trajectories under an electric field in an ion source of a mass spectrometer according to an embodiment of the present invention;

[0043] Figure 7 2. The characteristic curve of the ion source transmission efficiency changing with the spray voltage according to the embodiment of the present invention;

[0044] Figure 8 2. The characteristic curve of the ion source transmission efficiency changing with the atomizing gas flow rate according to the embodiment of the present invention;

[0045] Figure 9 2 is a characteristic curve of the ion source transmission efficiency changing with the drying gas flow rate according to an embodiment of the present invention;

[0046] Figure 10 2 is a characteristic curve of the ion source transmission efficiency changing with the air curtain gas flow rate according to an embodiment of the present invention;

[0047] Figure 11 1 is a characteristic curve of ion source transmission efficiency changing with exhaust pressure according to an embodiment of the present invention.

[0048] In the attached figure: 1. atomizing gas inlet; 2. drying gas inlet; 3. air curtain gas inlet; 4. exhaust port; 5. sampling cone hole; 6. ion source cavity; 7. ion source exhaust cavity. DETAILED DESCRIPTION

[0049] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0050] Example:

[0051] It should be noted that the terms "including" and "having" in the embodiments of the present invention and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or devices.

[0052] When simulating the physical processes within an ion source, the lack of comprehensive and accurate coupled analysis of multiple physical fields results in significant deviations from actual predictions of ion trajectories and transmission efficiency. Traditional research methods often consider either the flow field or the electric field in isolation, ignoring the strong interplay between the two. For example, when analyzing ion motion in an electric field, the interference of flow drag on the ion's path is not fully considered, resulting in distorted simulation results.

[0053] Figure 1 FIG. 1 is a flow chart of a method for simulating and analyzing the transmission efficiency characteristics of an ion source of a mass spectrometer according to an embodiment of the present invention. Figure 1 As shown, an embodiment of the present invention provides a method for simulating and analyzing the transmission efficiency characteristics of an ion source of a mass spectrometer, comprising the following steps:

[0054] Step 1: Obtain the structural parameter data of the mass spectrometer ion source prototype to be simulated and analyzed.

[0055] Figure 2 FIG. 1 is a schematic structural diagram of a prototype of the mass spectrometer ion source in an embodiment of the present invention. Figure 1 As shown, the mass spectrometer ion source prototype specifically includes:

[0056] Ion source chamber; illustratively, the ion source chamber is a cylindrical structure;

[0057] The atomizing gas inlet, drying gas inlet and air curtain gas inlet are connected to the ion source cavity; for example, the atomizing gas inlet is arranged at the top center of the ion source cavity, and is used to inject atomizing gas into the ion source cavity; there are two drying gas inlets distributed circumferentially around the ion source cavity, and are used to transport drying gas into the ion source cavity to help remove the solvent during the ionization process; the air curtain gas inlet is arranged at the front of the ion source cavity, and is used to form an air curtain to block external impurities and guide the movement of ions

[0058] The ion source exhaust chamber is connected to the ion source chamber, and the ion source exhaust chamber is connected to an exhaust port; illustratively, the ion source exhaust chamber is arranged at the bottom of the ion source chamber, and the exhaust port is connected to the bottom of the ion source exhaust chamber, and the exhaust port is used to exhaust the gas in the system to maintain a suitable air pressure environment; the ion source exhaust chamber assists in exhausting and ensures the stability of the air pressure in the ion source

[0059] The sampling cone hole is located at the center of the ion source cavity. For example, the sampling cone hole is responsible for capturing ions and is the location where the ion source transmission efficiency is calculated.

[0060] The structural parameter data of the mass spectrometer ion source prototype mainly includes its external dimension data.

[0061] Step 2: Construct a three-dimensional geometric model of the mass spectrometer ion source prototype using three-dimensional modeling software based on the structural parameter data.

[0062] Use professional 3D modeling software, such as SolidWorks, ANSYS Design Modeler, etc., to perform modeling operations based on the acquired structural parameter data.

[0063] Step 3: Based on the three-dimensional geometric model, discretization is performed using a meshing method to generate a mesh model suitable for multi-physics field simulation.

[0064] By dividing the grid, the complex three-dimensional geometric model of the mass spectrometer ion source prototype is divided into many small, simple grid cells. After grid division, the three-dimensional geometric model is discretized. Originally continuous physical quantities, such as velocity and pressure in the flow field, and electric potential and field intensity in the electric field, can be solved at the nodes of each grid cell. In this way, the partial differential equations describing physical phenomena (such as equations in turbulence models and magnetohydrodynamic models) can be converted into a set of algebraic equations at discrete nodes, and solved using numerical calculation methods (such as finite element method, finite volume method, etc.), thereby obtaining the distribution of physical quantities in the entire mass spectrometer ion source and the motion trajectory of particles.

[0065] Step 4: Based on the grid model, by coupling the turbulence model, discrete phase model and magnetohydrodynamic model, the ions generated by electrospray are equivalent to particles and a multi-physics field simulation model is constructed.

[0066] The coupled turbulence model, discrete phase model and magnetohydrodynamic model means that the turbulence model is used to describe the turbulent characteristics of the gas flow in the ion source cavity, the magnetohydrodynamic model is used to describe the force of the electric field on the particles, and the discrete phase model is used for the motion trajectory of the particles in the flow field and the electric field. For example, the airflow vortex predicted by the turbulence model (such as the vortex barrier formed by the air curtain) constrains the range of ion motion and reduces ion loss. The axial electric field gradient generated by the magnetohydrodynamic model (such as the high pressure difference near the sampling cone) accelerates the migration of ions to the cone. Combining the flow field drag and the electric field driving force, the discrete phase model counts the number of particles (n) entering the sampling cone.

[0067] Specifically, the coupled turbulence model is determined according to the following formula:

[0068] Assuming that the flow is incompressible, the K equation and ε equation are used to describe the dynamic characteristics of the turbulent field of particles:

[0069]

[0070] Where, It represents the rate of change of the turbulent kinetic energy k of unit volume fluid per unit time, represents the convection term of turbulent kinetic energy k, u i represents the macroscopic velocity of the fluid, is the diffusion term of turbulent kinetic energy k, μ is the molecular viscosity coefficient, μ t is the turbulent viscosity, σ k is the turbulent kinetic energy diffusion coefficient; G k represents the generation term of turbulent kinetic energy k caused by the mean velocity gradient, -ρε represents the dissipation term of turbulent kinetic energy, ρ is the fluid density, and ε is the turbulent kinetic energy dissipation rate;

[0071] The magnetohydrodynamic model is determined by the following formula:

[0072] Magnetohydrodynamic model based on electric potential method:

[0073]

[0074] represents the electric field strength, and are scalar electric potential and vector electric potential respectively.

[0075] The discrete phase model is determined according to the following formula:

[0076] The equation for the force acting on the particle is:

[0077]

[0078] Among them, m p is the particle mass, is the fluid velocity, is the particle velocity, ρ is the fluid density, ρ p is the particle density, τ r is the relaxation time, q is the particle charge, is the electric field strength, represents the fluid drag force on the particle, represents gravity, Represents the electric field force.

[0079] is the relaxation time τ r Determine according to the following formula

[0080]

[0081] Where: ρ p is the particle density, d p is the particle diameter, μ is the fluid dynamic viscosity, C d is the drag coefficient, Re is the Reynolds number, ρ is the fluid density, is the particle velocity, is the fluid velocity.

[0082] The drag coefficient C is determined using the dynamic drag model theory. d :

[0083]

[0084] To achieve the coupling between flow drag and electric forces, the electric field and its associated forces are introduced through user-defined functions (UDFs) and user-defined scalars (UDSs). Specifically, UDSs introduce the Laplace equation, which is used in electrostatics to describe the electric potential distribution. Incorporating this equation into the simulation model helps determine the potential distribution within the ion source. By solving the Laplace equation using UDSs, the simulation software can calculate the potential at each point within the ion source.

[0085] Next, the influence of the electric field on the discrete phase model is incorporated through UDF. The electric field is introduced using four custom scalars, which are used to store the electric potential and the electric field strength in the X, Y, and Z directions respectively. In the simulation of the mass spectrometer ion source, the movement of ion particles is affected not only by the drag force of the flow field, but also by the electric field force. By integrating the influence of the electric field on the momentum equation through UDF, the effects of these two forces can be considered simultaneously when calculating the motion of ion particles. Specifically, the simulation software calculates the electric field force based on the electric field strength and the charge of the ion particles, and incorporates it into the momentum equation, so that the simulation can more accurately reflect the movement of ions under the combined action of the flow field and the electric field.

[0086] To more accurately describe the characteristics of the electric field in space, four custom scalars are used. One scalar stores the electric potential, while the other three store the electric field strength in the X, Y, and Z directions. Within the ion source, the electric field is a vector field, and its magnitude and direction can vary at different locations. These four custom scalars record this electric field information at different spatial locations and are updated in real time during the simulation based on the calculated results, thus achieving a precise description of the electric field.

[0087] Step 5: Based on the multi-physics field simulation model and the preset boundary conditions, the internal flow field distribution, electric field intensity distribution and ion trajectory data of the mass spectrometer ion source are obtained by numerical calculation methods, and the ion transmission efficiency data is calculated based on the flow field distribution, electric field intensity and ion trajectory data.

[0088] The preset boundary conditions include flow field simulation boundary conditions, electric field simulation boundary conditions, and discrete phase boundary conditions. For example, the flow field simulation conditions include an atomizing gas inlet velocity of 5-10 m / s, a drying gas inlet velocity of 35-50 m / s, a curtain gas inlet velocity of 5-12 m / s, and an exhaust pressure of -45,000 to 65,000 Pa. The electric field simulation conditions include a spray voltage of 5,000-5,500 V, a curtain baffle voltage of 1,000 V, and a sampling cone voltage of 100 V. The discrete phase boundary conditions include a conical jet pattern, jet direction, a cone angle of 15°, a jet spatial position, a particle diameter, and a wall type.

[0089] Among them, the existing technology has obvious defects when dealing with the complex process of ion generation by electrospray ionization sources. During the electrospray process, the initial droplets undergo solvent evaporation and Coulomb explosion to form smaller droplets and eventually ionize. However, traditional methods are difficult to accurately describe this dynamic process. The estimation of key parameters such as the initial droplet radius, the number of small droplets after splitting, and the charge is inaccurate, and thus the generation and transmission of ions cannot be accurately simulated, which seriously affects the evaluation and optimization of ion source performance. In the process of ion particle generation by electrospray, the size of the particle diameter (2R) is relatively critical, and it is closely related to the droplet density ρ p , volume flow rate Q p , the solvent surface tension is related to δ, and the particle radius R can be estimated using the following formula:

[0090] R∝(ρ p Q p δ) 1 / 3

[0091] During the electrospray process, the initial droplets will undergo two important processes: solvent evaporation and Coulomb explosion. Solvent evaporation gradually reduces the solvent in the droplets, resulting in a reduction in the droplet volume. Coulomb explosion is due to the accumulation of surface charges on the droplets. When the repulsive force between the charges exceeds the surface tension of the droplets, the droplets will explode and split. After these two processes, the initial droplets will form smaller droplets. The number of small droplets n is related to the initial droplet radius R and the final droplet radius r. n = R 3 / r 3 This means that the larger the initial droplet radius, the more small droplets will be produced by the final splitting; and the smaller the final droplet radius, the more small droplets will be produced. This formula provides a quantitative basis for studying the splitting behavior of droplets during the electrospray process and helps analyze the generation and distribution of ions in the ion source.

[0092] The initial droplet forms smaller droplets through solvent evaporation and Coulomb explosion, and after splitting, n small droplet particles are produced, n = R 3 / r 3 , r is the radius of the final droplet. The charge on the droplet particles is estimated using the following formula:

[0093]

[0094] Here, δ is the surface tension of the solvent, and e is the dielectric constant of the solution. As can be seen from the formula, the charge carried by the droplet is proportional to the 3 / 2 power of the final droplet radius, and is also related to the dielectric constant of the solution and the surface tension of the solvent. The dielectric constant reflects the response characteristics of the solution to the electric field, while the surface tension affects the stability of the droplet. Together, they determine the amount of charge carried by the droplet. This formula is very important when studying the movement of ions in an electric field, because the charge carried by the droplet directly affects the magnitude of the electric field force on the ion, which in turn affects the ion's trajectory and transmission efficiency within the mass spectrometer's ion source.

[0095] This step requires determining a series of boundary conditions, covering multiple aspects such as flow field, electric field and discrete phase boundary conditions. These boundary conditions simulate the physical environment of the mass spectrometer ion source in actual operation, such as the atomizing gas inlet velocity set at 5-10m / s, the spray voltage set at 5000-5500V, etc. By applying these boundary conditions to the previously established multi-physics field coupling simulation model, the real physical process inside the ion source can be simulated, making the simulation as close to the actual situation as possible. In this way, the physical phenomena inside the ion source can be reproduced on the computer, including the flow of gas, the distribution of the electric field and the movement of ion particles.

[0096] Through the above-mentioned multi-physics field simulation, the flow field, electric field, and ion particle motion trajectory inside the ion source can be obtained. Flow field information can display the flow velocity and pressure distribution of the gas in the ion source, which is very important for understanding the transport process of ions in the gas, because the flow of gas will generate drag on the ions, affecting their movement direction and speed. Electric field information reflects the distribution of electric field strength and potential within the ion source. The electric field force is one of the key factors driving ion motion and determines the acceleration and deflection of the ions. The ion particle motion trajectory intuitively presents the movement path of ions under the combined action of the flow field and electric field. By observing the motion trajectory, the behavior of ions in the ion source can be analyzed.

[0097] Figure 4 This is a flow field distribution diagram in the ion source of a mass spectrometer according to an embodiment of the present invention; Figure 5 ion trajectory diagram in the absence of an electric field in the ion source of a mass spectrometer according to an embodiment of the present invention; Figure 6 This is a diagram of ion trajectories under an electric field in the ion source of a mass spectrometer according to an embodiment of the present invention.

[0098] In practical applications, it is hoped that as many ions as possible can be captured by the sampling cone to improve the detection sensitivity of the mass spectrometer. By counting the number of ion particles entering the sampling cone (set as n) and comparing it with the total number of ions (set as N), the ion transmission efficiency is calculated as follows:

[0099]

[0100] Where η is the transmission efficiency, n is the number of particles captured by the sampling cone, and N is the total number of particles. The transmission efficiency is determined by the ratio of the number of ions captured by the sampling cone to the total number of ions. It directly reflects the proportion of ions generated by the ion source that are successfully captured by the sampling cone.

[0101] Step 5: Generate a transmission efficiency characteristic curve of the mass spectrometer ion source prototype through a parameterized simulation method based on the ion transmission efficiency data.

[0102] Parametric simulation refers to the process of expressing various influencing factors (such as physical quantities, geometric dimensions, boundary conditions, etc.) in the model using parameters when establishing the simulation model. By changing the values of these parameters, the model can be easily simulated and analyzed under different working conditions.

[0103] Specifically, the spray voltage, atomizing gas flow rate, drying gas flow rate, curtain gas flow rate and exhaust pressure are adjusted by a single variable control method, and a parameterized simulation method is used to generate a quantitative curve of the transmission efficiency as a function of each parameter. For example, by changing the main atomizing gas flow rate, a characteristic curve of the mass spectrometer ion source transmission efficiency as a function of the main atomizing gas flow rate is obtained by simulation; by changing the auxiliary atomizing gas flow rate, a characteristic curve of the mass spectrometer ion source transmission efficiency as a function of the auxiliary atomizing gas flow rate is obtained by simulation; by changing the curtain gas flow rate, a characteristic curve of the mass spectrometer ion source transmission efficiency as a function of the curtain gas flow rate is obtained by simulation; and by changing the exhaust pressure, a characteristic curve of the mass spectrometer ion source transmission efficiency as a function of the exhaust pressure is obtained by simulation. Figure 7 2. The characteristic curve of the ion source transmission efficiency changing with the spray voltage according to the embodiment of the present invention; Figure 8 2. The characteristic curve of the ion source transmission efficiency changing with the atomizing gas flow rate according to the embodiment of the present invention; Figure 9 2 is a characteristic curve of the ion source transmission efficiency changing with the drying gas flow rate according to an embodiment of the present invention; Figure 10 2 is a characteristic curve of the ion source transmission efficiency changing with the air curtain gas flow rate according to an embodiment of the present invention; Figure 11 1 is a characteristic curve of ion source transmission efficiency changing with exhaust pressure according to an embodiment of the present invention.

[0104] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0105] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the essence of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A method for simulating and analyzing the transmission efficiency characteristics of a mass spectrometer ion source, characterized in that: The following steps are involved: Obtaining structural parameter data of a mass spectrometer ion source prototype to be simulated and analyzed; Constructing a three-dimensional geometric model of the mass spectrometer ion source prototype using three-dimensional modeling software according to the structural parameter data; Based on the three-dimensional geometric model, a discretization process is performed using a meshing method to generate a mesh model suitable for multi-physics field simulation; Based on the grid model, by coupling the turbulence model, discrete phase model and magnetohydrodynamic model, the ions generated by electrospray are equivalent to particles, and a multi-physics field simulation model is constructed; According to the multi-physics field simulation model and preset boundary conditions, the internal flow field distribution, electric field intensity distribution and ion trajectory data of the mass spectrometer ion source are obtained by numerical calculation method, and the ion transmission efficiency data is calculated based on the flow field distribution, electric field intensity distribution and ion trajectory data; According to the ion transmission efficiency data, a transmission efficiency characteristic curve of the mass spectrometer ion source prototype is generated by a parameterized simulation method.

2. The method for simulating and analyzing the transmission efficiency characteristics of a mass spectrometer ion source according to claim 1, wherein: The mass spectrometer ion source prototype specifically comprises: ion source chamber; an atomizing gas inlet, a drying gas inlet and a curtain gas inlet connected to the ion source cavity; An ion source exhaust chamber connected to the ion source chamber, wherein the ion source exhaust chamber is connected to an exhaust port; A sampling cone is located in the center of the ion source cavity.

3. The method for simulating and analyzing the transmission efficiency characteristics of a mass spectrometer ion source according to claim 1, wherein: The coupled turbulence model is determined according to the following formula: Assuming that the flow is incompressible, the K equation and ε equation are used to describe the dynamic characteristics of the turbulent field of particles: Where, It represents the rate of change of the turbulent kinetic energy k of unit volume fluid per unit time, represents the convection term of turbulent kinetic energy k, u i represents the macroscopic velocity of the fluid, is the diffusion term of turbulent kinetic energy k, μ is the molecular viscosity coefficient, μ t is the turbulent viscosity, σ k is the turbulent kinetic energy diffusion coefficient; G k represents the generation term of turbulent kinetic energy k caused by the mean velocity gradient, -ρε represents the dissipation term of turbulent kinetic energy, ρ is the fluid density, and ε is the turbulent kinetic energy dissipation rate; represents the rate of change of turbulent kinetic energy dissipation rate ε with time, The convective term representing the turbulent kinetic energy dissipation rate ε, represents the effect of the turbulent kinetic energy generated by the mean velocity gradient on the turbulent kinetic energy dissipation rate, represents the effect of the turbulent kinetic energy generated by the mean velocity gradient on the turbulent kinetic energy dissipation rate; is the dissipation term of the turbulent kinetic energy dissipation rate ε, C 1ε and C 2ε and C μ All are empirical constants.

4. The method for simulating and analyzing the transmission efficiency characteristics of a mass spectrometer ion source according to claim 1, wherein: The magnetohydrodynamic model is determined by the following formula: Magnetohydrodynamic model based on electric potential method: represents the electric field strength, and are scalar electric potential and vector electric potential respectively.

5. The method for simulating and analyzing the transmission efficiency characteristics of a mass spectrometer ion source according to claim 1, wherein: The discrete phase model is determined according to the following formula: The equation for the force acting on the particle is: Among them, m p is the particle mass, is the fluid velocity, is the particle velocity, ρ is the fluid density, ρ p is the particle density, τ r is the relaxation time, q is the particle charge, is the electric field strength, represents the fluid drag force on the particle, represents gravity, Represents the electric field force.

6. The method for simulating and analyzing the transmission efficiency characteristics of a mass spectrometer ion source according to claim 1, wherein: The ion transmission efficiency is determined by the ratio of the number of ion particles entering the sampling cone to the preset total number of particles, based on the flow field distribution, electric field strength distribution and ion trajectory data.

7. The method for simulating and analyzing the transmission efficiency characteristics of a mass spectrometer ion source according to claim 1, wherein: The preset boundary conditions include flow field simulation boundary conditions, electric field simulation boundary conditions and discrete phase boundary conditions.

8. The method for simulating and analyzing the transmission efficiency characteristics of a mass spectrometer ion source according to claim 1, wherein: The spray voltage, atomizing gas flow, drying gas flow, curtain gas flow and exhaust pressure were adjusted by single variable control method to generate a quantitative curve of transmission efficiency as a function of each parameter.

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