A method and system for calculating airflow-ice crystal coupling in a compressor

Abstract

The present invention discloses a calculation method and system for the coupling effect of airflow and ice crystals in a compressor, and relates to the technical field of ice crystal icing in aircraft and engines. The method comprises: solving the Navier-Stokes equations using a CFD method to obtain an initial airflow field; the initial airflow field comprises the pressure, velocity, temperature and shear stress of the air in the compressor; based on the initial airflow field, constructing an air flow field calculation model and an ice crystal particle motion phase change model respectively, and coupling calculations are performed on the air flow field calculation model and the ice crystal particle motion phase change model to obtain ice crystal particle impact characteristic results; the ice crystal particle impact characteristic results are used to represent the airflow-ice crystal coupling effect in the compressor. The present invention can obtain the coupled heat and mass transfer process of airflow and ice crystals in the engine structure, which helps to improve the recognition and understanding of the coupled heat and mass transfer characteristics between ice crystals and air when they move inside the engine.

Description

Technical Field

[0001] The invention relates to the technical field of ice crystal icing of aircraft and engines, and in particular to a calculation method and system for airflow-ice crystal coupling in a compressor. Background Art

[0002] The icing problem of aircraft and engines has always been an important factor threatening flight safety. Earlier related research mainly focused on the icing of supercooled water droplets. Relevant investigations and studies have shown that commercial aircraft often experience engine failure accidents at altitudes exceeding 7,000 meters, and the cause of the accident is ice crystal icing caused by high-altitude ice crystals entering the engine.

[0003] A large number of studies have shown that the premise of ice crystal freezing is the presence of liquid water, which comes from supercooled water droplets in the environment or the melting of ice crystals during movement. Therefore, it is necessary to conduct numerical simulation research on the phase change process of ice crystal particles in the compressor. The simulation of ice crystal motion trajectory basically follows the Lagrangian method and Euler method commonly used in supercooled water droplet trajectory calculation.

[0004] However, current research on ice crystal icing mainly focuses on the impact of warm air flow environment on the phase change of ice crystal particle movement. A few studies have considered the impact of humid air on engine performance, and few have considered the interaction between ice crystal particles and ambient airflow, especially the coupling process between airflow and ice crystal particles in a real compressor structure. Summary of the invention

[0005] The purpose of the present invention is to provide a calculation method and system for the airflow-ice crystal coupling effect in a compressor, which can obtain the coupled heat and mass transfer process of the airflow-ice crystals in the engine structure, and help to improve the recognition and understanding of the coupled heat and mass transfer characteristics between ice crystals and air when they move inside the engine.

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

[0007] A method for calculating airflow-ice crystal coupling in a compressor, comprising:

[0008] The CFD method is used to solve the Navier-Stokes equation to obtain the initial airflow field; the initial airflow field includes the pressure, velocity, temperature and shear stress of the air in the compressor;

[0009] Based on the initial airflow field, an air flow field calculation model and an ice crystal particle motion phase change model are respectively constructed, and the air flow field calculation model and the ice crystal particle motion phase change model are coupled and calculated to obtain ice crystal particle impact characteristic results; the ice crystal particle impact characteristic results are used to represent the airflow-ice crystal coupling effect in the compressor.

[0010] Optionally, the air flow field calculation model includes a multi-component model, each of the component models is used to calculate the flow of humid air, and the humid air includes two components: dry air and water vapor.

[0011] Optionally, the mass, momentum and energy conservation equations of the humid air are respectively as follows:

[0012]

[0013]

[0014]

[0015]

[0016] Among them, ρ a is the density of moist air, t is the time, u a is the air speed, Y i is the mass fraction of water vapor, u, v, w are the velocity components of air in three directions, S i is the water vapor source phase generated by the sublimation and evaporation of ice crystal particles, S u ,S v ,S w is the generalized source phase of the momentum equation, μ a is the air viscosity, Φ s is the part of mechanical energy converted into heat energy due to viscosity, S h is the source phase generated by the heat exchange between ice crystal particles and fluid; h is the enthalpy value; λ a is the thermal conductivity of air; T a is the air temperature.

[0017] Optionally, the water vapor source phase generated by the sublimation / evaporation of the ice crystal particles and the source phase generated by the heat exchange between the ice crystal particles and the fluid are obtained from the evaporation model and the convection heat transfer model of the ice crystal particles, respectively:

[0018]

[0019]

[0020] Among them, α is the ice crystal volume fraction, V is the control volume, φ is the particle sphericity, d p is the equivalent diameter of ice particles, ρ p is the ice particle density, LWC is the liquid water content, Sh is the Sherwood number, D v is the diffusion coefficient, Y v,s and Y v,∞ represent the mass fraction of the particle surface and the vapor in the ambient airflow, respectively; Nu is the Nusselt number, and T p is the ice particle temperature.

[0021] Optionally, the ice crystal particle motion phase transition model is constructed based on the total volume fraction of ice crystal particles and the motion phase transition process principle of ice crystal particles, and includes three-stage control equations; wherein the total volume fraction of ice crystal particles includes the volume fraction α of solid ice i and the volume fraction of liquid water α w The total volume fraction of the ice crystal particles is specifically: α = α i +α w , represents the volume occupied by particles per unit volume; the relationship between the volume fraction change rate and mass change rate of ice crystal particles is as follows:

[0022]

[0023] Among them, ρ p is the density of ice crystal particles; is the melting mass; d p is the equivalent diameter of the ice particle.

[0024] Optionally, the three-stage control equation specifically includes:

[0025] In the first stage, the ice crystal particles are in solid state and the temperature T<T m ,α=α i ,Φ=Φ0:

[0026]

[0027]

[0028]

[0029]

[0030] Among them, L sub is the latent heat of sublimation, u is the velocity vector of ice crystal particles, ρ i is the density of ice, ρ w is the density of water, is the volume fraction change rate of sublimation, c p,i is the specific heat capacity of solid ice at constant pressure, C D is the drag coefficient, Re is the Reynolds number, n is the particle number density, ρ a is the density of moist air, D v is the diffusion coefficient, Sh is the Sherwood number, Φ is the thermal energy, d p is the equivalent diameter of ice particles, Y v,s and Y v,∞ represent the mass fraction of the vapor on the particle surface and in the ambient airflow, α is the ice crystal volume fraction, μ a is the air viscosity, ua is the air velocity, λ a is the thermal conductivity of air, Nu is the Nusselt number, t is the time, T is the current temperature, T m is the melting temperature of ice crystals;

[0031] In the second stage, the ice crystal particles gradually melt, and a liquid water film surrounds the ice core, forming a solid-liquid mixed state. The temperature in this stage is T = T m ,α=α i +α w ,Φ∈(Φ0,1]:

[0032]

[0033]

[0034]

[0035]

[0036]

[0037] Among them, L ev is the latent heat of evaporation, L m is the latent heat of melting, is the volume fraction change rate of evaporation, is the melting volume fraction change rate, c p,w is the specific heat capacity of liquid water at constant pressure;

[0038] In the third stage, the ice crystal particles completely melt into spherical water droplets, which are in liquid state, and the temperature T>T m ,α=α w ,Φ=1:

[0039]

[0040]

[0041]

[0042]

[0043]

[0044] The present invention also provides a calculation system for airflow-ice crystal coupling in a compressor, comprising:

[0045] The initial field providing module is used to solve the Navier-Stokes equations using the CFD method to obtain the initial airflow field; the initial airflow field includes the pressure, velocity, temperature and shear stress of the air in the compressor;

[0046] The airflow-ice crystal coupling calculation module is used to construct an air flow field calculation model and an ice crystal particle motion phase change model based on the initial airflow field, and to couple the air flow field calculation model and the ice crystal particle motion phase change model to obtain ice crystal particle impact characteristic results; the ice crystal particle impact characteristic results are used to represent the airflow-ice crystal coupling effect in the compressor.

[0047] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0048] The present invention discloses a calculation method and system for airflow-ice crystal coupling in a compressor, the method comprising using a CFD method to solve the Navier-Stokes equations to obtain an initial airflow field; the initial airflow field comprises the pressure, velocity, temperature and shear stress of the air in the compressor; based on the initial airflow field, an air flow field calculation model and an ice crystal particle motion phase change model are respectively constructed, and the air flow field calculation model and the ice crystal particle motion phase change model are coupled and calculated to obtain ice crystal particle impact characteristic results; the ice crystal particle impact characteristic results are used to represent the airflow-ice crystal coupling in the compressor. The present invention can obtain the coupled heat and mass transfer process of airflow-ice crystals in the engine structure, which helps to improve the recognition and understanding of the coupled heat and mass transfer characteristics between ice crystals and air when they move inside the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0050] Figure 1 It is a two-dimensional cross-sectional schematic diagram of the Stage35 stator rotor in this embodiment;

[0051] Figure 2 This is a comparison chart of the calculated pressure ratio and the experimental results in this embodiment;

[0052] Figure 3 This is the Langmuir-D distribution diagram in this embodiment;

[0053] Figure 4 : is a cloud diagram of ice crystal content in this embodiment; wherein, part (a) is a schematic diagram of solid ice volume fraction; part (b) is a schematic diagram of liquid water volume fraction;

[0054] Figure 5 : is a cloud diagram of water vapor mass fraction in this embodiment;

[0055] Figure 6 Schematic diagram of the surface melting rate of the stator and rotor blades under different particle size conditions in this embodiment; wherein, part (a) is a schematic diagram of the surface melting rate of the rotor blades; part (b) is a schematic diagram of the surface melting rate of the stator blades;

[0056] Figure 7 Schematic diagram of the collection coefficient of the surface of the rotor blade under different particle size conditions in this embodiment; wherein, part (a) is a schematic diagram of the collection coefficient of the surface of the rotor blade; part (b) is a schematic diagram of the collection coefficient of the surface of the stator blade;

[0057] Figure 8 Schematic diagram of air flow temperature change along the process in this embodiment;

[0058] Fig. 9 Schematic diagram of the change of air flow moisture content along the process in this embodiment;

[0059] Fig.10 Schematic diagram of the flow chart of the method for calculating the airflow-ice crystal coupling effect in the compressor according to the present embodiment. DETAILED DESCRIPTION

[0060] The following will be combined with the 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 described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] The purpose of the present invention is to provide a calculation method and system for the airflow-ice crystal coupling effect in a compressor, which can obtain the coupled heat and mass transfer process of the airflow-ice crystals in the engine structure, and help to improve the recognition and understanding of the coupled heat and mass transfer characteristics between ice crystals and air when they move inside the engine.

[0062] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0063] like Figure 1-Figure 10 As shown, the present invention provides a method for calculating the airflow-ice crystal coupling effect in a compressor, comprising:

[0064] Step 100: Solve the Navier-Stokes equations using the CFD method to obtain the initial airflow field; the initial airflow field includes the distribution of physical quantities such as pressure, velocity, temperature and shear stress of the air in the compressor.

[0065] Step 200: Based on the initial airflow field, considering the movement phase change process of ice crystal particles in the compressor structure under ice crystal icing weather conditions, an air flow field calculation model and an ice crystal particle movement phase change model are constructed respectively, and the air flow field calculation model and the ice crystal particle movement phase change model are coupled and calculated to obtain ice crystal particle impact characteristic results; the ice crystal particle impact characteristic results are used to represent the airflow-ice crystal coupling effect in the compressor.

[0066] As a further solution of step 200, the air flow field calculation model uses a multi-component model to calculate the flow of humid air, including two components: dry air and water vapor. The mass, momentum and energy conservation equations are as follows:

[0067]

[0068]

[0069]

[0070]

[0071] Among them, ρ a is the density of moist air, t is the time, u a is the air speed, Y i is the mass fraction of water vapor, u, v, w are the velocity components of air in three directions, S i is the water vapor source phase generated by the sublimation and evaporation of ice crystal particles, S u ,S v ,S w is the generalized source phase of the momentum equation, μ a is the air viscosity, Φ s is the part of mechanical energy converted into heat energy due to viscosity, S h is the source phase generated by the heat exchange between ice crystal particles and fluid; h is the enthalpy value; λ a is the thermal conductivity of air; T a is the air temperature.

[0072] The water vapor source phase generated by the sublimation\evaporation of the ice crystal particles and the source phase generated by the heat exchange between the ice crystal particles and the fluid are obtained from the evaporation model of the ice crystal particles and the convection heat transfer model, respectively:

[0073]

[0074]

[0075] Among them, α is the ice crystal volume fraction, V is the control volume, φ is the particle sphericity, d p is the equivalent diameter of ice particles, ρ pis the ice particle density, LWC is the liquid water content, Sh is the Sherwood number, D v is the diffusion coefficient, Y v,s and Y v,∞ represent the mass fraction of the particle surface and the vapor in the ambient airflow, respectively; Nu is the Nusselt number, and T p is the ice particle temperature.

[0076] Ice crystal particles will appear in the form of solid ice and liquid water at the same time during the phase change process. Therefore, the total volume fraction of ice crystal particles is divided into two parts, namely, the volume fraction of solid ice α i and the volume fraction of liquid water α w , respectively described in their respective Euler governing equations. The total volume fraction of ice crystal particles α = α i +α w , which represents the volume occupied by particles per unit volume. The relationship between the volume fraction change rate and mass change rate of ice crystal particles is as follows:

[0077]

[0078] Among them, ρ p is the density of ice crystal particles; is the melting mass; d p is the equivalent diameter of the ice particle.

[0079] The motion phase change process of ice crystal particles takes into account the resistance, heat transfer and phase change model encountered by the above-mentioned ice crystal particles during their motion process, and the three-stage control equation of the ice crystal particles is obtained, which is specifically expressed as follows:

[0080] In the first stage, the ice crystal particles are in solid state and the temperature T<T m ,α=α i ,Φ=Φ0:

[0081]

[0082]

[0083]

[0084]

[0085]

[0086] Among them, L sub is the latent heat of sublimation, u is the velocity vector of ice crystal particles, ρ i is the density of ice, ρ w is the density of water, is the volume fraction change rate of sublimation, c p,i is the specific heat capacity of solid ice at constant pressure, CD is the drag coefficient, Re is the Reynolds number, n is the particle number density, ρ a is the density of moist air, D v is the diffusion coefficient, Sh is the Sherwood number, Φ is the thermal energy, d p is the equivalent diameter of ice particles, Y v,s and Y v,∞ represent the mass fraction of the vapor on the particle surface and in the ambient airflow, α is the ice crystal volume fraction, μ a is the air viscosity, u a is the air velocity, λ a is the thermal conductivity of air, Nu is the Nusselt number, t is the time, T is the current temperature, T m is the melting temperature of ice crystals;

[0087] In the second stage, the ice crystal particles gradually melt, and a liquid water film surrounds the ice core, forming a solid-liquid mixed state. The temperature in this stage is T = T m ,α=α i +α w ,Φ∈(Φ0,1]:

[0088]

[0089]

[0090]

[0091]

[0092]

[0093] Among them, L ev is the latent heat of evaporation, L m is the latent heat of melting, is the volume fraction change rate of evaporation, is the melting volume fraction change rate, c p,w is the specific heat capacity of liquid water at constant pressure;

[0094] In the third stage, the ice crystal particles completely melt into spherical water droplets, which are in liquid state, and the temperature T>T m ,α=α w ,Φ=1:

[0095]

[0096]

[0097]

[0098]

[0099]

[0100] Model application results

[0101] Existing ice crystal particle motion phase change models only consider the influence of the airflow environment on the ice crystal particle motion phase change process, and ignore the influence of the heat and mass transfer process of ice crystal particles on the air flow field. Therefore, for the coupled heat and mass transfer process of ice crystal particles and air flow field in the compressor, the present invention establishes an airflow-ice crystal coupling model and calculation method, and performs calculations in the actual compressor structure.

[0102] This example uses the stage 35 compressor as the calculation object. NASA Stage 35 is a typical impeller product designed for the inlet stage of the compressor in the current engine. It includes a first-stage rotor and a first-stage stator. There are 36 rotor blades and 46 stator blades. The two-dimensional cross-sectional diagram of the first-stage stator rotor is as follows: Figure 1 In order to save computing resources, one of the rotor blades and one stator blade is selected and calculated in combination with periodic boundary conditions.

[0103] The compressor inlet total pressure is 101325Pa, the inlet total temperature is 288.15K, the pressure outlet is 17188.7rpm. The calculated results of the compressor under dry conditions are compared with the experimental results. The compressor performance curve can be obtained by changing the outlet pressure. The calculated compressor performance curve results are shown in Figure 2 As shown, the pressure ratio results are consistent with the experimental results, the maximum pressure ratio differs by 4.47%, and the overall flow field calculation results are in good agreement with the experimental data.

[0104] The above-mentioned airflow-ice crystal coupling calculation model and method are used to calculate the motion phase change process of ice crystal particles inside the compressor when stage 35 is running under ice crystal icing meteorological conditions. In order to make the motion phase change phenomenon more obvious, the average diameter of ice crystal particles is taken as 20 μm. At the same time, considering that the size of ice crystal particles in the actual atmospheric environment is not uniform, this embodiment uses 7 particles with different particle sizes that conform to the Langmuir-D distribution for calculation. The cumulative content of ice crystals with different particle sizes is as follows: Figure 3 By iteratively solving the control equations of the air flow field and ice crystal motion phase change in the entire computational domain, the distribution of the air flow field in the compressor under ice crystal freezing conditions and the volume fraction of solid ice of ice crystal particles, the volume fraction of liquid water, particle velocity, temperature, particle size, and density field distribution results are finally obtained.

[0105] Figure 4 This is a cloud diagram of the volume fraction of solid ice and liquid water in ice crystal particles in stage 35. Figure 4It can be seen in (a) that the ice crystal particles are mainly concentrated on the pressure side of the rotor blade, while there are almost no ice crystal particles on the suction side of the rotor blade, which is similar to the "water droplet shielding area" in the flow of supercooled water. Figure 4 (b) is a cloud diagram of the volume fraction of liquid water in ice crystal particles in stage 35. It can be seen that the liquid water in the ice crystal particles begins to appear at the rotor blades, because at the rotor blades, the air flow field temperature rises to a temperature higher than the melting temperature of the ice crystal particles, and the ice crystals begin to melt under the action of convective heat exchange with the warm air flow. Figure 5 This is a cloud diagram of water vapor mass fraction. The water vapor content at the entrance is zero. With the sublimation and evaporation of ice crystal particles during movement, the water vapor content also increases significantly.

[0106] Figure 6 is the melting rate of ice crystal particles under different particle size conditions, and the position of the two-dimensional curve is 0.22m away from the axis of rotation. Whether on the surface of the rotor or the stator blade, the change law of the melting rate of ice crystal particles is consistent. The melting rate is the lowest when it just reaches the surface of the rotor blade, and then as the ice crystal particles move backward, the melting rate gradually increases. The melting rate of ice crystal particles with a diameter of 6.2μm on the stator surface has reached 0.404, while the melting rate of ice crystal particles with a diameter of 44.4μm is only 0.015. When the ice crystal particles move to the surface of the stator blade, the overall melting rate of the particles is greater than that of the rotor blade. The melting rate of ice crystal particles with a diameter of 6.2μm has reached 0.7, which is almost completely melted. On the one hand, it is because the particles move for a longer time and the endothermic melting process is more complete; on the other hand, the compressor structure heats and pressurizes the airflow, making the ambient airflow temperature at the stator blade higher, and the heat exchange between the ice crystal particles and the airflow more intense.

[0107] Figure 7 The results of the ice crystal particle collection coefficient for different particle sizes show that as the particle size increases, the collection coefficient on the rotor blade surface increases, while the collection coefficient on the stator blade surface decreases. This is because the larger the particle size, the greater the particle inertia, making it easier to hit the rotor blade surface, and the larger the particle size, the smaller the deflection of the airflow, resulting in fewer ice crystal particles hitting the stator blade surface. The particle collection coefficient determines the different content of ice crystal particles hitting the stator and rotor surfaces.

[0108] The movement and phase change of ice crystals in the compressor will change the temperature and humidity of the air flow inside the compressor. Figure 8This is the temperature change along the compressor under dry air conditions and ice crystal icing conditions with different particle sizes. It can be seen that under ice crystal icing meteorological conditions, the ambient temperature at the stage 35 outlet does not change much. Compared with dry air conditions, the temperature under icing meteorological conditions has different degrees of reduction. The static temperature of the airflow under each particle size condition has decreased by 0.25768K, and the total temperature has decreased by 0.30142K. Due to the small content of ice crystal particles, the heat exchange between ice crystal particles and ambient airflow is less than the specific heat of airflow, and the icing meteorological conditions have little effect on the overall temperature distribution (about 0.08%).

[0109] The change of humidity content of air flow along the way is as follows Fig. 9 As shown, assuming that the inlet moisture content is 0, the water vapor content in the air gradually increases as the ice crystal particles sublimate / evaporate along the flow direction. Under the condition of particle size of 6.2μm, more water vapor evaporates, and the moisture content reaches 0.11044g / kg(a), while under the condition of particle size of 44.4μm, it is only 0.00132g / kg(a). Because the smaller the particle size, the larger its relative surface area, the larger the heat and mass transfer area, and the more water vapor sublimates / evaporates under the same mass. Under icing meteorological conditions, considering the conditions under various particle sizes, the total moisture content of the ambient airflow increased by 0.06735g / kg(a).

[0110] In addition, the present invention also provides a calculation system for airflow-ice crystal coupling in a compressor, comprising:

[0111] The initial field providing module is used to solve the Navier-Stokes equations using the CFD method to obtain the initial airflow field; the initial airflow field includes the pressure, velocity, temperature and shear stress of the air in the compressor;

[0112] The airflow-ice crystal coupling calculation module is used to construct an air flow field calculation model and an ice crystal particle motion phase change model based on the initial airflow field, and to couple the air flow field calculation model and the ice crystal particle motion phase change model to obtain ice crystal particle impact characteristic results; the ice crystal particle impact characteristic results are used to represent the airflow-ice crystal coupling effect in the compressor.

[0113] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0114] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for calculating the airflow-ice crystal coupling effect in a compressor, characterized in that: include: The CFD method is used to solve the Navier-Stokes equation to obtain the initial airflow field; the initial airflow field includes the pressure, velocity, temperature and shear stress of the air in the compressor; Based on the initial airflow field, an air flow field calculation model and an ice crystal particle motion phase change model are respectively constructed, and the air flow field calculation model and the ice crystal particle motion phase change model are coupled and calculated to obtain ice crystal particle impact characteristic results; the ice crystal particle impact characteristic results are used to represent the airflow-ice crystal coupling effect in the compressor; The air flow field calculation model includes a plurality of component models, each of which is used to calculate the flow of moist air, wherein the moist air includes two components: dry air and water vapor; The mass, momentum and energy conservation equations of the moist air are as follows: Among them, ρ a is the density of moist air, t is the time, u a is the air speed, Y i is the mass fraction of water vapor, u, v, w are the velocity components of air in three directions, S i is the water vapor source phase generated by the sublimation and evaporation of ice crystal particles, S u ,S v ,S w is the generalized source phase of the momentum equation, μ a is the air viscosity, Φ s is the part of mechanical energy converted into heat energy due to viscosity, S h is the source phase generated by the heat exchange between ice crystal particles and fluid; h is the enthalpy value; λ a is the thermal conductivity of air; T a is the air temperature; The water vapor source phase generated by the sublimation\evaporation of the ice crystal particles and the source phase generated by the heat exchange between the ice crystal particles and the fluid are obtained from the evaporation model of the ice crystal particles and the convection heat transfer model, respectively: Among them, α is the ice crystal volume fraction, V is the control volume, φ is the particle sphericity, d p is the equivalent diameter of ice particles, ρ p is the ice particle density, LWC is the liquid water content, Sh is the Sherwood number, D v is the diffusion coefficient, Y v,s and Y v,∞ represent the mass fraction of the particle surface and the vapor in the ambient airflow, respectively; Nu is the Nusselt number, and T p is the ice particle temperature; The ice crystal particle motion phase transition model is constructed based on the total volume fraction of ice crystal particles and the motion phase transition process principle of ice crystal particles, and includes three-stage control equations; wherein the total volume fraction of ice crystal particles includes the volume fraction α of solid ice i and the volume fraction of liquid water α w The total volume fraction of the ice crystal particles is specifically: α = α i +α w , represents the volume occupied by particles per unit volume; the relationship between the volume fraction change rate and mass change rate of ice crystal particles is as follows: Among them, ρ p is the density of ice crystal particles; is the melting mass; d p is the equivalent diameter of ice particles, and α is the volume fraction of ice crystals.

2. The method for calculating the airflow-ice crystal coupling effect in the compressor according to claim 1, characterized in that: The three-stage control equation specifically includes: In the first stage, the ice crystal particles are in solid state and the temperature T<T m ,α=α i ,Φ=Φ0: Among them, L sub is the latent heat of sublimation, u is the velocity vector of ice crystal particles, ρ i is the density of ice, ρ w is the density of water, is the volume fraction change rate of sublimation, c p,i is the specific heat capacity of solid ice at constant pressure, C D is the drag coefficient, Re is the Reynolds number, n is the particle number density, ρ a is the density of moist air, D v is the diffusion coefficient, Sh is the Sherwood number, Φ is the thermal energy, d p is the equivalent diameter of ice particles, Y v,s and Y v,∞ represent the mass fraction of the vapor on the particle surface and in the ambient airflow, α is the ice crystal volume fraction, μ a is the air viscosity, u a is the air velocity, λ a is the thermal conductivity of air, Nu is the Nusselt number, t is the time, T is the current temperature, T m is the melting temperature of ice crystals; In the second stage, the ice crystal particles gradually melt, and a liquid water film surrounds the ice core, forming a solid-liquid mixed state. The temperature in this stage is T = T m ,α=α i +α w ,Φ∈(Φ0,1]: Among them, L ev is the latent heat of evaporation, L m is the latent heat of melting, is the volume fraction change rate of evaporation, is the melting volume fraction change rate, c p,w is the specific heat capacity of liquid water at constant pressure; In the third stage, the ice crystal particles completely melt into spherical water droplets, which are in liquid state, and the temperature T>T m ,α=α w ,Φ=1:

3. A system for calculating the coupling effect of airflow and ice crystals in a compressor, applied to the method according to any one of claims 1 to 2, characterized in that: include: The initial field providing module is used to solve the Navier-Stokes equations using the CFD method to obtain the initial airflow field; the initial airflow field includes the pressure, velocity, temperature and shear stress of the air in the compressor; The airflow-ice crystal coupling calculation module is used to construct an air flow field calculation model and an ice crystal particle motion phase change model based on the initial airflow field, and to couple the air flow field calculation model and the ice crystal particle motion phase change model to obtain ice crystal particle impact characteristic results; the ice crystal particle impact characteristic results are used to represent the airflow-ice crystal coupling effect in the compressor.

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