Bubble dynamic characteristic prediction method and system considering phase change effect near water area boundary

Abstract

The invention discloses a bubble dynamic characteristic prediction method and system considering a phase change effect near a water area boundary, and relates to the field of cavitation bubble dynamics. The method solves the problems that when bubbles near a boundary are processed by an existing analytical model, due to the fact that the wall effect and the flow field heterogeneity are ignored, deformation and migration tracks of the bubbles are difficult to accurately reflect, and a prediction result deviates from the actual situation, the method comprises the steps that initial conditions and environment parameters of the bubbles are input; calculating a boundary induced flow field pressure, and calculating a flow field environment pressure based on the boundary induced pressure and the hydrostatic pressure; calculating bubble internal pressure based on a thermodynamic phase change effect; calculating the bubble surface enthalpy difference based on the flow field environment pressure and the bubble internal pressure; and substituting the obtained result into a uniform-form bubble equation considering the phase change and migration effects, and solving to obtain a bubble equivalent radius and migration distance which change along with time. The method is also suitable for the field of equivalent radius calculation for predicting a single cavitation bubble in the boundary movement process.

Description

Technical Field

[0001] The present invention relates to the technical field of cavitation bubble dynamics, and in particular to a method and system for predicting bubble dynamics characteristics considering phase change effects near a water area boundary. Background Art

[0002] Cavitation is the process in which bubbles are generated and developed in liquids under certain special conditions (for example, when the local pressure drops below the saturated vapor pressure). It is widely found in the fields of hydraulic machinery, ship propellers, and microfluidic devices. The nucleation, growth, collapse, and interaction of bubbles in the fluid with the surrounding boundaries will not only lead to a decrease in the operating efficiency of the equipment, but may also cause erosion on the surface of the material or cause noise and vibration. At the same time, people are constantly exploring and utilizing the characteristics of high temperature, high pressure impact, and strong turbulence brought by cavitation, and applying it to the fields of ultrasonic cleaning, sewage treatment, material modification, and microfluidic chips. For example, sound-induced cavitation can generate strong local high temperature and high pressure at the moment of collapse of tiny cavitation bubbles, promoting the increase of chemical reaction rate; and in water treatment or emulsification processes, the turbulence generated by cavitation can enhance mixing and promote dissolution, thereby further improving the treatment efficiency. Therefore, how to avoid or reduce the harm caused by cavitation and effectively utilize its advantageous effects has become an important research topic in fluid mechanics and engineering applications.

[0003] At present, the research methods for predicting the motion characteristics of bubbles under cavitation conditions mainly include theoretical analytical models and numerical simulations. Among them, the analytical method based on the Rayleigh–Plesset equation and its improved model can provide a relatively simplified description of the growth and collapse process of a single bubble, with high computational efficiency. However, in the dynamic process of bubbles near the boundary, affected by the non-uniform distribution of the flow field and the wall effect, traditional analytical models are often difficult to accurately describe the bubble deformation and motion trajectory. At the same time, although the use of commercial CFD software or independently developed numerical simulation methods can better capture the dynamic evolution of the gas-liquid two-phase interface, when dealing with phase change effects (phase change between liquid and vapor inside the bubble) and the coupling of wall boundary conditions, higher requirements are put forward for the meshing accuracy, boundary condition setting and the rationality of the phase change model, and these requirements require more computing resources.

[0004] Most current studies still have the following shortcomings when simulating bubble motion near boundaries: First, traditional analytical models such as the Rayleigh–Plesset equation ignore the wall effect and flow field heterogeneity when dealing with bubbles near boundaries, making it difficult to accurately reflect the deformation and migration trajectory of the bubbles, resulting in the prediction results deviating from the actual situation; second, although the existing CFD method has advantages in simulating complex flow fields and gas-liquid interface dynamics, it still faces challenges in the accurate coupling of phase change effects and requires more computing resources; in addition, although the existing high-order theoretical models take some complex factors into account, they are still insufficient in the comprehensive coupling description of the phase change process and bubble dynamics, and the complexity of their analytical solutions limits their practicality in variable engineering environments. Summary of the invention

[0005] The present invention aims to solve the problems that analytical models in the prior art, such as the Rayleigh–Plesset equation, ignore the wall effect and flow field non-uniformity when dealing with bubbles near the boundary, making it difficult to accurately reflect the deformation and migration trajectory of the bubbles, resulting in the prediction results deviating from the actual situation; secondly, although the existing CFD method has advantages in simulating complex flow fields and gas-liquid interface dynamics, it still faces challenges in the precise coupling of phase change effects and requires more computing resources; in addition, although the existing high-order theoretical model takes some complex factors into consideration, it is still insufficient in the comprehensive coupling description of the phase change process and bubble dynamics, and the complexity of its analytical solution limits its practicality in a variable engineering environment.

[0006] To solve the above technical problems, the present invention is achieved through the following technical solutions:

[0007] Solution 1: The present invention proposes a method for predicting bubble dynamic characteristics near a water area boundary taking into account phase change effects, the method comprising the following steps:

[0008] S1, input the initial conditions and environmental parameters of the bubble;

[0009] S2, using the mirror method to set the mirror bubble parameters and calculate the boundary-induced flow field pressure, and calculating the flow field environmental pressure based on the boundary-induced pressure and the hydrostatic pressure;

[0010] S3, calculating the internal pressure of the bubble based on the thermodynamic phase change effect;

[0011] S4, calculating the bubble surface enthalpy difference based on the flow field ambient pressure described in S2 and the bubble internal pressure described in S3;

[0012] S5. Substitute the results obtained from S2 to S4 into the unified form of the bubble equation that takes into account the phase change and migration effects and solve it to obtain the bubble equivalent radius and migration distance that change with time, and complete the prediction of the bubble dynamic characteristics considering the phase change effect near the water boundary.

[0013] Furthermore, a preferred embodiment is provided, wherein the initial conditions of the bubble input in S1 include the initial radius of the bubble, the initial internal pressure of the bubble, the water depth at the center of the bubble, and the distance between the bubble and the boundary; the environmental parameters include fluid density, flow field reference sound velocity, fluid saturated vapor pressure, fluid surface tension, fluid dynamic viscosity, flow field temperature, and gravitational acceleration.

[0014] Further, a preferred embodiment is provided, in which the method for setting the parameters of the mirror bubble by using the mirror method in S2 is:

[0015]

[0016] Among them, R and v are the radius and migration speed of the real bubble, R I 、v I is the mirror bubble v I The radius and migration speed.

[0017] Further, a preferred embodiment is provided, in which the method for calculating the flow field ambient pressure based on the boundary induced pressure in S2 is:

[0018]

[0019] Among them, R is the position vector of the real bubble, ρ is the fluid density, is the velocity potential induced by the mirror bubble, u I is the flow field velocity induced by the mirror bubble; where u I and The expression is:

[0020]

[0021] Where H is the enthalpy difference and d is the distance between the bubble center and the boundary at time t.

[0022] Further, a preferred embodiment is provided, in which the method for calculating the internal pressure of the bubble based on the thermodynamic phase change effect in step 3 is:

[0023]

[0024] Where P g is the pressure of the gas inside the bubble, that is, the steam and non-condensable gas, σ is the surface tension, μ is the viscosity of the fluid, ρ g is the average density of gas inside the bubble; It is the evaporation or condensation rate per unit area of ​​the bubble surface.

[0025] Further, a preferred embodiment is provided, the evaporation or condensation rate per unit area of ​​the bubble surface The calculation method is:

[0026]

[0027] Among them, α m is the adaptation factor; P v (T l ) is the liquid at T l Saturated vapor pressure at temperature, P vb is the actual vapor pressure inside the bubble; β is the correction factor.

[0028] Further, a preferred implementation is provided, in which the unified form of the bubble equation considering the phase change and migration effects in step 4 is:

[0029]

[0030] Among them, υ is the migration velocity vector and γ is the drag force coefficient.

[0031] Solution 2: A bubble dynamics characteristics prediction system considering phase change effects near the water boundary, the system comprising:

[0032] An input module, used to input the initial conditions and environmental parameters of the bubble;

[0033] A flow field environment pressure calculation module is used to set the mirror bubble parameters and calculate the boundary-induced flow field pressure by using the mirror method, and calculate the flow field environment pressure based on the boundary-induced pressure and the hydrostatic pressure;

[0034] A bubble internal pressure calculation module is used to calculate the bubble internal pressure based on the thermodynamic phase change effect;

[0035] A bubble surface enthalpy difference calculation module, used to calculate the bubble surface enthalpy difference based on the flow field environment pressure described in the flow field environment pressure calculation module and the bubble internal pressure described in the bubble internal pressure calculation module;

[0036] The prediction module is used to substitute the results obtained from the flow field environmental pressure calculation module to the bubble surface enthalpy difference calculation module into the unified form of the bubble equation that considers the phase change and migration effects and solve it, so as to obtain the bubble equivalent radius and migration distance that change with time, and complete the prediction of the bubble dynamic characteristics considering the phase change effect near the water area boundary.

[0037] Solution three: A computer device includes a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor executes any one of the methods described in Solution one.

[0038] Solution 4: A computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps of the method described in any one of Solution 1.

[0039] The present invention is beneficial in that:

[0040] The method and system for predicting bubble dynamic characteristics considering phase change effects near the boundary of water area described in the present invention proposes a method for calculating bubble motion near the boundary taking into account phase change effects, which has important research necessity and application value. The method can not only accurately predict the dynamic changes of bubble radius, but also synchronously simulate the spatiotemporal migration behavior of bubbles, comprehensively consider the influence of phase change process on bubble dynamics, thereby significantly improving the accuracy and reliability of cavitation bubble motion prediction, and saving a lot of computing resources.

[0041] The present invention is based on a bubble equation with a unified form that takes into account phase change and migration effects, and adopts a mirror method to design the flow field pressure induced by the boundary on the bubble. At the same time, the migration and compressibility of the thermodynamic effect are considered to achieve the purpose of accurately predicting the movement behavior of bubbles near the boundary, providing a theoretical basis and basic technical support for engineering construction.

[0042] The present invention is also applicable to the field of theoretical calculation methods for accurately predicting the equivalent radius and migration of a single cavitation bubble during its movement near a boundary. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is a flow chart of the method for predicting bubble dynamic characteristics considering phase change effects near the water area boundary described in Implementation Example 1.

[0044] Figure 2 This is a schematic diagram of the mirror method described in Implementation Method 1.

[0045] Figure 3 Schematic diagram of the phase change effect on the surface of the bubble in the first embodiment.

[0046] Figure 4 This is a time history curve effect diagram of the predicted equivalent radius of the electric spark bubble near the free surface as described in the eleventh embodiment.

[0047] Figure 5 This is a time history curve effect diagram of predicting the migration distance of the spark bubble near the free surface described in the first implementation mode.

[0048] Figure 6This is a time history curve effect diagram of the predicted equivalent radius of the laser pulse bubble near the rigid boundary described in Implementation Example 1.

[0049] Figure 7 This is a time history curve effect diagram of predicting the migration distance of laser pulse bubbles near a rigid boundary as described in Implementation Example 1. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solutions and advantages of the implementation methods of the present application clearer, the technical solutions in the implementation methods of the present application will be clearly and completely described below in conjunction with the drawings in the implementation methods of the present application. Obviously, the described implementation methods are only part of the implementation methods of the present application, not all of the implementation methods.

[0051] Embodiment 1: This embodiment proposes a method for predicting bubble dynamic characteristics near a water area boundary taking into account phase change effects, the method comprising the following steps:

[0052] S1, input the initial conditions and environmental parameters of the bubble;

[0053] S2, using the mirror method to set the mirror bubble parameters and calculate the boundary-induced flow field pressure, and calculating the flow field environmental pressure based on the boundary-induced pressure and the hydrostatic pressure;

[0054] S3, calculating the internal pressure of the bubble based on the thermodynamic phase change effect;

[0055] S4, calculating the bubble surface enthalpy difference based on the flow field ambient pressure described in S2 and the bubble internal pressure described in S3;

[0056] S5. Substitute the results obtained from S2 to S4 into the unified form of the bubble equation that takes into account the phase change and migration effects and solve it to obtain the bubble equivalent radius and migration distance that change with time, and complete the prediction of the bubble dynamic characteristics considering the phase change effect near the water boundary.

[0057] Implementation method 2. This implementation method is a further limitation of the method for predicting bubble dynamic characteristics considering the phase change effect near the water boundary described in implementation method 1. The initial conditions of the bubble input in S1 include the initial radius of the bubble, the initial internal pressure of the bubble, the water depth at the center of the bubble, and the distance between the bubble and the boundary; the environmental parameters include fluid density, flow field reference sound velocity, fluid saturated vapor pressure, fluid surface tension, fluid dynamic viscosity, flow field temperature, and gravitational acceleration.

[0058] Embodiment 3: This embodiment further limits the method for predicting bubble dynamic characteristics considering phase change effect near the water area boundary described in embodiment 1. The method for setting the parameters of the mirror bubble using the mirror method in S2 is:

[0059]

[0060] Among them, R and v are the radius and migration speed of the real bubble, R I 、v I is the mirror bubble v I The radius and migration speed.

[0061] Embodiment 4: This embodiment further limits the method for predicting bubble dynamic characteristics considering phase change effect near the water area boundary described in embodiment 1. The method for calculating the flow field ambient pressure based on the boundary induced pressure in S2 is:

[0062]

[0063] Among them, R is the position vector of the real bubble, ρ is the fluid density, is the velocity potential induced by the mirror bubble, u I is the flow field velocity induced by the mirror bubble; where u I and The expression is:

[0064]

[0065] Where H is the enthalpy difference and d is the distance between the bubble center and the boundary at time t.

[0066] Embodiment 5: This embodiment further limits the method for predicting bubble dynamic characteristics considering phase change effect near the water boundary described in embodiment 1. The method for calculating the internal pressure of the bubble based on the thermodynamic phase change effect in step 3 is:

[0067]

[0068] Where P g is the pressure of the gas inside the bubble, that is, the steam and non-condensable gas, σ is the surface tension, μ is the viscosity of the fluid, ρ g is the average density of gas inside the bubble; It is the evaporation or condensation rate per unit area of ​​the bubble surface.

[0069] Embodiment 6: This embodiment further limits the prediction method of bubble dynamic characteristics considering phase change effect near the water boundary described in Embodiment 5. The evaporation or condensation rate per unit area of ​​the bubble surface The calculation method is:

[0070]

[0071] Among them, α m is the adaptation factor; P v (T l) is the liquid at T l Saturated vapor pressure at temperature, P vb is the actual vapor pressure inside the bubble; β is the correction factor.

[0072] Embodiment 7: This embodiment further limits the method for predicting bubble dynamic characteristics considering phase change effect near the water boundary described in embodiment 1. The unified form of the bubble equation considering phase change and migration effect in step 4 is:

[0073]

[0074] Among them, υ is the migration velocity vector and γ is the drag force coefficient.

[0075] Embodiment 8: This embodiment proposes a bubble dynamics characteristics prediction system considering phase change effects near the water boundary, the system comprising:

[0076] An input module, used to input the initial conditions and environmental parameters of the bubble;

[0077] A flow field environment pressure calculation module is used to set the mirror bubble parameters and calculate the boundary-induced flow field pressure by using the mirror method, and calculate the flow field environment pressure based on the boundary-induced pressure and the hydrostatic pressure;

[0078] A bubble internal pressure calculation module is used to calculate the bubble internal pressure based on the thermodynamic phase change effect;

[0079] A bubble surface enthalpy difference calculation module, used to calculate the bubble surface enthalpy difference based on the flow field environment pressure described in the flow field environment pressure calculation module and the bubble internal pressure described in the bubble internal pressure calculation module;

[0080] The prediction module is used to substitute the results obtained from the flow field environmental pressure calculation module to the bubble surface enthalpy difference calculation module into the unified form of the bubble equation that considers the phase change and migration effects and solve it, so as to obtain the bubble equivalent radius and migration distance that change with time, and complete the prediction of the bubble dynamic characteristics considering the phase change effect near the water area boundary.

[0081] Embodiment 9. This embodiment proposes a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor executes the method described in any one of embodiments 1 to 7.

[0082] Embodiment 10: This embodiment proposes a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the steps of the method described in any one of Embodiments 1 to 7 are implemented.

[0083] Embodiment 11: This embodiment provides an example, which is used to explain the above embodiments 1 to 8. Figures 1 to 7 To illustrate this implementation mode, the embodiments are specifically as follows:

[0084] Step 1: Input the initial conditions and environmental parameters of the bubble.

[0085] Step 2: Based on the boundary type and the distance between the bubble and the boundary at the initial moment, design the expression of the ambient pressure at the center of the bubble under the influence of the boundary.

[0086] Step three, based on the phase change effect, calculate the internal pressure of the bubble, and calculate the bubble surface enthalpy difference in combination with step two.

[0087] Step 4: Substitute the results obtained in steps 2 and 3 into the bubble equation with a unified form that takes into account phase change and migration effects and solve it to obtain the bubble equivalent radius and migration distance that change with time.

[0088] Specifically, in step 1, the initial conditions and environmental parameters of the bubble are input. The initial conditions of the bubble include the initial radius of the bubble, the initial internal pressure of the bubble, the water depth at the center of the bubble, and the distance between the bubble and the boundary; the environmental parameters include fluid density, flow field reference sound velocity, fluid saturated vapor pressure, fluid surface tension, fluid dynamic viscosity, flow field temperature, and gravity acceleration. By modifying the above initial information parameters, the initial state of the bubble and the environmental conditions of the water area can be set.

[0089] Furthermore, in step 2, according to the boundary type, the boundary reflection coefficient α is set, a coordinate system is established and the x-axis coincides with the boundary surface, and the parameters of the mirror bubble are set using the mirror method:

[0090]

[0091] Where R and v are the radius and migration speed of the real bubble, R I 、v I is the mirror bubble v I The radius and migration speed of the mirror image method. Figure 2 shown.

[0092] Furthermore, based on the Bernoulli equation, the flow field pressure P induced by the boundary at the center of the bubble at time t is obtained: B expression:

[0093]

[0094] Among them, R is the position vector of the real bubble, ρ is the fluid density, is the velocity potential induced by the mirror bubble, u Iis the flow field velocity induced by the mirror bubble. I and The expression is:

[0095]

[0096] Where H is the enthalpy difference, and d is the distance between the bubble center and the boundary at time t. According to formula (2), the ambient pressure P at the bubble center can be obtained: a =P B +P ∞ , P ∞ =ρgh is the hydrostatic pressure.

[0097] Furthermore, in step three, a thermodynamic model is introduced to consider the phase change effect, and the bubble surface pressure calculation formula taking into account the phase change is obtained according to the bubble surface pressure balance relationship:

[0098]

[0099] Where P g is the pressure of the gas (steam and non-condensable gas) inside the bubble, σ is the surface tension, μ is the viscosity of the fluid, ρ g is the average density of gas inside the bubble; is the evaporation or condensation rate per unit area of ​​the bubble surface. The steam and non-condensable gas in the bubble are regarded as ideal gases, and both are treated to be uniformly distributed inside the bubble. The principle of the phase change effect on the bubble surface is as follows Figure 3 As shown. g Calculated according to the ideal gas state equation:

[0100]

[0101] Where M is the total mass of steam and non-condensable gases, T b is the internal temperature of the bubble, V is the volume of the bubble, R g is the mixed gas constant in the bubble. b and R g Calculate as follows:

[0102]

[0103] Among them, c v and c p are the specific heat capacity of gas at constant volume and constant pressure, S b is the bubble surface area, is the heat exchange rate of the bubble surface per unit time, κ is the heat transfer coefficient, T l is the temperature of the surrounding fluid; M v and M n are the masses of steam and non-condensable gas, Rv and R n are the gas constants for the masses of steam and non-condensable gases, respectively.

[0104] Furthermore, the phase transition rate in (4) Calculate as follows:

[0105]

[0106] Among them, α m is the adaptation factor; P v (T l ) is the liquid at T l Saturated vapor pressure at temperature, P vb is the actual vapor pressure inside the bubble; Γ is the correction factor.

[0107] Furthermore, combining equation (4) with the ambient pressure P obtained in step 2 a , calculate the enthalpy difference H according to the following formula:

[0108]

[0109] Steps 2 and 3 are an iterative solution process. In step 2, P is initially solved. a When the enthalpy difference in formula (3) is H = (P b -P ∞ ) / ρ calculation, and then solve for P B , and then proceed to step 3 to obtain the enthalpy difference after the first iteration. Next, the initial enthalpy difference in each time step is calculated according to the enthalpy difference after the previous iteration.

[0110] Furthermore, in step 4, the bubble equation with a unified form for describing bubble pulsation and migration is:

[0111]

[0112] Where υ is the migration velocity vector and γ is the drag coefficient. Solving equation (9), we can obtain the equivalent radius and migration distance that change with time during the bubble movement. Figure 4 , Figure 5 They are respectively the time history curve effect diagrams of the present invention for predicting the equivalent radius and migration distance of the electric spark bubble near the free surface; Figure 6 , Figure 7 They are respectively time history curve effect diagrams of the present invention for predicting the equivalent radius and migration distance of the laser pulse bubble near the rigid boundary.

[0113] Those skilled in the art will appreciate that the above are only preferred embodiments of the present invention, and the various embodiments of the present disclosure and / or the features described in the claims may be combined or combined in various ways, even if such combinations or combinations are not explicitly described in the present disclosure. It is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or perform equivalent substitutions on some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

[0114] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for predicting bubble dynamic characteristics near the water boundary considering phase change effects, characterized in that: The method comprises the following steps: S1, input the initial conditions and environmental parameters of the bubble; S2, using the mirror method to set the mirror bubble parameters and calculate the boundary-induced flow field pressure, and calculating the flow field environmental pressure based on the boundary-induced pressure and the hydrostatic pressure; S3, calculating the internal pressure of the bubble based on the thermodynamic phase change effect; S4, calculating the bubble surface enthalpy difference based on the flow field ambient pressure described in S2 and the bubble internal pressure described in S3; S5. Substitute the results obtained from S2 to S4 into the unified form of the bubble equation that takes into account the phase change and migration effects and solve it to obtain the bubble equivalent radius and migration distance that change with time, and complete the prediction of the bubble dynamic characteristics considering the phase change effect near the water boundary.

2. The method for predicting bubble dynamic characteristics considering phase change effect near the water area boundary according to claim 1 is characterized in that: The initial conditions of the bubble input in S1 include the initial radius of the bubble, the initial internal pressure of the bubble, the water depth at the center of the bubble, and the distance between the bubble and the boundary; the environmental parameters include fluid density, flow field reference sound velocity, fluid saturated vapor pressure, fluid surface tension, fluid dynamic viscosity, flow field temperature, and gravitational acceleration.

3. The method for predicting bubble dynamic characteristics considering phase change effect near the water area boundary according to claim 1 is characterized in that: The method for setting the parameters of the mirror bubble using the mirror method in S2 is: Among them, R and v are the radius and migration speed of the real bubble, R I 、v I is the mirror bubble v I The radius and migration speed.

4. The method for predicting bubble dynamic characteristics considering phase change effect near the water area boundary according to claim 1 is characterized in that: The method for calculating the flow field ambient pressure based on the boundary induced pressure in S2 is: Among them, R is the position vector of the real bubble, ρ is the fluid density, is the velocity potential induced by the mirror bubble, u I is the flow field velocity induced by the mirror bubble; where u I and The expression is: Where H is the enthalpy difference and d is the distance between the bubble center and the boundary at time t.

5. The method for predicting bubble dynamic characteristics considering phase change effect near the water area boundary according to claim 1 is characterized in that: The method for calculating the internal pressure of the bubble based on the thermodynamic phase change effect in step 3 is: Where P g is the pressure of the gas inside the bubble, that is, the steam and non-condensable gas, σ is the surface tension, μ is the viscosity of the fluid, ρ g is the average density of gas inside the bubble; It is the evaporation or condensation rate per unit area of ​​the bubble surface.

6. The method for predicting bubble dynamic characteristics considering phase change effect near the water area boundary according to claim 5 is characterized in that: The evaporation or condensation rate per unit area of ​​the bubble surface The calculation method is: Among them, α m is the adaptation factor; P v (T l ) is the liquid at T l Saturated vapor pressure at temperature, P vb is the actual vapor pressure inside the bubble; β is the correction factor.

7. The method for predicting bubble dynamic characteristics considering phase change effect near the water area boundary according to claim 1 is characterized in that: The unified form of the bubble equation considering phase change and migration effects in step 4 is: Among them, υ is the migration velocity vector and γ is the drag force coefficient.

8. A bubble dynamics prediction system considering phase change effects near the water boundary, characterized by: The system comprises: An input module, used to input the initial conditions and environmental parameters of the bubble; A flow field environment pressure calculation module is used to set the mirror bubble parameters and calculate the boundary-induced flow field pressure by using the mirror method, and calculate the flow field environment pressure based on the boundary-induced pressure and the hydrostatic pressure; A bubble internal pressure calculation module is used to calculate the bubble internal pressure based on the thermodynamic phase change effect; A bubble surface enthalpy difference calculation module, used to calculate the bubble surface enthalpy difference based on the flow field environment pressure described in the flow field environment pressure calculation module and the bubble internal pressure described in the bubble internal pressure calculation module; The prediction module is used to substitute the results obtained from the flow field environmental pressure calculation module to the bubble surface enthalpy difference calculation module into the unified form of the bubble equation that considers the phase change and migration effects and solve it, so as to obtain the bubble equivalent radius and migration distance that change with time, and complete the prediction of the bubble dynamic characteristics considering the phase change effect near the water area boundary.

9. A computer device comprising a memory and a processor, characterized in that A computer program is stored in the memory. When the processor runs the computer program stored in the memory, the processor executes the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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