Surface electric field intensity simulation method and system based on two-phase flow field

Abstract

The invention relates to the technical field of electric field intensity analysis, and discloses a surface electric field intensity simulation method and system based on a two-phase flow field, and the method comprises the steps: determining the motion process of bubbles in a two-phase flow field material in a non-uniform field, and carrying out the simulation modeling of the motion process of the bubbles through a bubble motion control equation, a two-dimensional electric field model of the insulating surface of each bubble is established through a plurality of bubbles adsorbed on the surface in a simulation cavity area obtained through modeling, and the surface electric field intensity distribution of the two-phase flow field material is determined by using the two-dimensional electric field models, so that the control of the bubble motion dynamic process is accurately determined; and the surface electric field intensity distribution simulation precision and the insulation performance evaluation precision are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric field strength analysis, and in particular to a surface electric field strength simulation method and system based on a two-phase flow field. Background Art

[0002] Gas-liquid two-phase flow refers to a flow system involving the interaction of gas and liquid phases, which is widely used in the fields of nuclear power, energy, machinery, aerospace and daily life, such as chemical reactors, bubbling beds, heat exchangers, high-speed pumps, etc. For example, in the thermal design of thermal systems, boiling heat transfer is usually required in the heat exchange channel to fully utilize its latent heat and greatly enhance the heat transfer capacity.

[0003] The movement of bubbles in the gas-liquid mixed state will be affected by factors such as the electric field and liquid flow. Even under the same heating temperature and voltage conditions, the bubble size is still relatively random. The electric field strength distribution when the bubbles are attached to the insulating surface can easily have a greater impact on the insulation in the gas-liquid mixed state.

[0004] Therefore, it is necessary to analyze the surface electric field intensity distribution under the bubble motion in the two-phase flow field to evaluate the influence of the bubble on the insulation performance. The existing process of analyzing the surface electric field intensity distribution under the bubble motion in the two-phase flow field is difficult to accurately perform dynamic analysis on the bubble motion process, which easily leads to poor simulation accuracy of the surface electric field intensity distribution and affects the evaluation of the insulation performance. Summary of the invention

[0005] In view of this, the present invention provides a surface electric field strength simulation method and system based on a two-phase flow field, which solves the technical problem that the existing process of analyzing the surface electric field strength distribution under the bubble motion in the two-phase flow field is difficult to accurately perform dynamic analysis on the bubble motion process, which easily leads to poor simulation accuracy of the surface electric field strength distribution and affects the evaluation of insulation performance.

[0006] A first aspect of the present invention provides a surface electric field intensity simulation method based on a two-phase flow field, comprising:

[0007] According to the movement process of bubbles in the two-phase flow field material in the inhomogeneous field, the bubble movement control equation is determined;

[0008] The motion process of the bubble is simulated and modeled according to the bubble motion control equation to obtain a simulated cavity area; wherein the simulated cavity area is used to limit the motion space of the bubble;

[0009] According to a plurality of bubbles adsorbed on the surface of the simulation cavity region in the simulation cavity region, a two-dimensional electric field model of the insulating surface of each bubble is established;

[0010] The surface electric field intensity distribution of the two-phase flow field material is determined according to the two-dimensional electric field models respectively corresponding to the plurality of bubbles.

[0011] Preferably, the bubble motion control equation is determined according to the motion process of the bubbles in the two-phase flow field material in the inhomogeneous field, including:

[0012] Decomposing the movement process of bubbles in the two-phase flow field material in the non-uniform field to obtain multiple movement stages of the movement process of the bubbles; the movement stages include an acceleration stage, a uniform speed stage and a deflection stage;

[0013] Analyzing the dynamic characteristics of the bubble at each movement stage to obtain a dynamic model of the bubble at each movement stage;

[0014] The bubble motion control equation is determined using the dynamic model of the bubble at each motion stage.

[0015] Preferably, the bubble motion control equation is:

[0016]

[0017] In the formula, To find the derivative symbol, is the bubble position vector, For time, and are the gas density and the phase change cooling medium density, is the acceleration due to gravity, is the dynamic viscosity of the medium, is the fluid flow velocity, is the bubble movement speed, is the bubble radius, is the dielectric constant inside the bubble, , represent the relative dielectric constants of the medium outside and inside the sphere, respectively. is the electric field strength at the bubble, and D is the bubble diameter.

[0018] Preferably, the step of establishing a two-dimensional electric field model of the insulating surface of each bubble according to a plurality of bubbles adsorbed on the surface of the simulation cavity region in the simulation cavity region comprises:

[0019] For each bubble adsorbed on the surface of the simulation cavity region, a tangent line is drawn between the bubble and the surface of the simulation cavity region to obtain a contact angle formed by the tangent line and the surface of the simulation cavity region;

[0020] A two-dimensional electric field model of the insulating surface of each bubble is determined according to the contact angles, bubble positions and surface electric field strengths corresponding to the plurality of bubbles.

[0021] Preferably, determining the surface electric field intensity distribution of the two-phase flow field material according to the two-dimensional electric field models corresponding to the plurality of bubbles respectively includes:

[0022] Performing fitting according to the two-dimensional electric field models respectively corresponding to the plurality of bubbles, to obtain a fitting relationship between the surface electric field strength and the contact angle and the bubble position;

[0023] Based on the fitting relationship, the surface electric field intensity distribution of the two-phase flow field material is determined according to the contact angles and bubble positions corresponding to all bubbles in the two-phase flow field material adsorbed on the surface of the simulation cavity area.

[0024] Preferably, the method further comprises:

[0025] The electric field enhancement coefficient is determined according to the surface electric field intensity corresponding to each bubble adsorbed on the surface of the simulated cavity area and the surface electric field intensity at the corresponding position on the surface of the simulated cavity area when there is no bubble; wherein the electric field enhancement coefficient is used to characterize the degree to which the bubble enhances the surface electric field intensity at different bubble positions and contact angles;

[0026] The electric field enhancement coefficients corresponding to the plurality of bubbles are fitted to obtain an electric field enhancement coefficient curve.

[0027] In a second aspect, the present invention further provides a surface electric field intensity simulation system based on a two-phase flow field, comprising:

[0028] A bubble motion control module is used to determine the bubble motion control equation according to the motion process of the bubbles in the two-phase flow field material in the inhomogeneous field;

[0029] A simulation modeling module, used for performing simulation modeling on the movement process of the bubble according to the bubble movement control equation to obtain a simulation cavity area; wherein the simulation cavity area is used to limit the movement space of the bubble;

[0030] An electric field modeling module, used for establishing a two-dimensional electric field model of the insulating surface of each bubble according to a plurality of bubbles adsorbed on the surface of the simulation cavity region in the simulation cavity region;

[0031] The field intensity distribution determination module is used to determine the surface electric field intensity distribution of the two-phase flow field material according to the two-dimensional electric field models corresponding to the multiple bubbles.

[0032] In a third aspect, the present invention further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the surface electric field strength simulation method based on the two-phase flow field as described in the first aspect.

[0033] In a fourth aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the steps of the surface electric field intensity simulation method based on the two-phase flow field as described in the first aspect.

[0034] In a fifth aspect, the present invention further provides a computer program product, comprising a computer program stored on a non-transitory computer-readable storage medium, wherein the computer program comprises program instructions, wherein when the program instructions are executed by a computer, the computer executes the steps of the surface electric field strength simulation method based on a two-phase flow field as described in the first aspect.

[0035] It can be seen from the above technical scheme that the present invention determines the movement process of bubbles in the two-phase flow field material in the inhomogeneous field, uses the bubble motion control equation to simulate and model the movement process of the bubbles, and establishes a two-dimensional electric field model of the insulating surface of each bubble through the multiple bubbles adsorbed on the surface in the simulated cavity area obtained by modeling, and uses the two-dimensional electric field model to determine the surface electric field intensity distribution of the two-phase flow field material, thereby accurately determining the control of the dynamic process of the bubble movement and improving the simulation accuracy of the surface electric field intensity distribution and the evaluation accuracy of the insulation performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] 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 or the description of the prior art 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.

[0037] Figure 1 A flow chart of a surface electric field intensity simulation method based on a two-phase flow field provided by an embodiment of the present invention;

[0038] Figure 2 is a schematic diagram of the simulated cavity area;

[0039] Figure 3 Schematic diagram of the force acting on the bubble;

[0040] Figure 4 Schematic diagram of bubble contact angle on rigid surface;

[0041] Figure 5 is the contour map of electric field strength on the insulation surface;

[0042] Figure 6 This is a schematic diagram of the simulation of the electric field strength on the surface of the insulator at position 1;

[0043] Figure 7 This is a schematic diagram of the simulation of the electric field strength on the surface of the insulator at position 2;

[0044] Figure 8 This is a schematic diagram of the simulation of the electric field strength on the surface of the insulator at position 3;

[0045] Fig. 9 A schematic diagram of the structure of a surface electric field intensity simulation system based on a two-phase flow field provided by an embodiment of the present invention;

[0046] Fig.10 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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.

[0048] An embodiment of the present application provides a surface electric field strength simulation method based on a two-phase flow field. The embodiment of the present application can be applicable to the situation of simulating the surface electric field strength of a two-phase flow field. The method can be executed by a surface electric field strength simulation device for a two-phase flow field. The surface electric field strength simulation device for a two-phase flow field can be implemented in the form of hardware and / or software. The surface electric field strength simulation device for a two-phase flow field can be configured in a computer device.

[0049] like Figure 1 As shown, the embodiment of the present application provides a surface electric field intensity simulation method based on a two-phase flow field, including the following steps S1 to S4. Among them:

[0050] Step S1, determining a bubble motion control equation according to the motion process of bubbles in a two-phase flow field material in an inhomogeneous field.

[0051] Since the volume of the bubble is extremely small compared to the entire extremely inhomogeneous field, the bubble can be simplified as a spherical bubble. In addition, the interaction force between bubbles, the spatial field strength generated by charged bubbles, and the electrostatic force between them can be ignored. The bubble is mainly affected by buoyancy, gravity, flow field drag, and electric field dielectrophoresis force.

[0052] The embodiment of the present application proposes to divide the movement of bubbles in an extremely non-uniform field into three stages: an acceleration stage, a uniform speed stage, and a deflection stage. Through the dynamic characteristics of the movement process of the bubbles in the non-uniform field, the control equation of the bubble motion can be derived, thereby determining the movement of the bubbles under the extremely non-uniform electric field.

[0053] Step S2, simulating and modeling the movement process of the bubble according to the bubble movement control equation to obtain a simulated cavity area; wherein the simulated cavity area is used to limit the movement space of the bubble.

[0054] The two-phase flow field material is simulated to determine the movement space of the bubbles inside the two-phase flow field material, thereby determining the simulation cavity area.

[0055] For example, Figure 2 As shown, the embodiment of the present application selects a simplified two-phase flow insulation test device as a simulation research object, and establishes a 100mm×100mm×100mm simulation cavity area to simulate the three movement processes of bubbles in an extremely non-uniform electric field.

[0056] The regional material of the simulated cavity area is set according to the actual value of FC-72 refrigerant (perfluorohexane). The density of FC-72 liquid is 1680kg / m 3 , conductivity is 10-15S / m, dynamic viscosity is 0.64Pa•s, relative dielectric constant is 1.75. The density of FC-72 gas is 15kg / m 3 , the conductivity is 0, and the relative dielectric constant is 1. When the medium flow rate is below 10 m / s, the fluid flow rate and pressure change is small, and the medium can be regarded as an incompressible fluid. The needle electrode applies the working voltage, and the plate electrode is grounded. In the extremely inhomogeneous field bubble simulation model, select the bubble inlet and set the radial velocity, and select the upper boundary of the cavity as the vanishing outlet.

[0057] Step S3: establishing a two-dimensional electric field model of the insulating surface of each bubble according to the plurality of bubbles adsorbed on the surface of the simulation cavity region in the simulation cavity region.

[0058] Among them, the bubbles of the phase change cooling two-phase flow flow through the extremely non-uniform field area and are affected by the dielectrophoretic force, and will deviate to varying degrees from the strong field area. As the two-phase flow rises, the bubbles will approach or adsorb on the insulating surface (the inner surface of the simulation cavity area), which will affect the insulation of the insulating surface. By establishing a two-dimensional electric field model of the insulating surface, the surface electric field strength simulation can be performed.

[0059] Step S4: determining the surface electric field intensity distribution of the two-phase flow field material according to the two-dimensional electric field models corresponding to the multiple bubbles.

[0060] The surface electric field intensity is simulated by using two-dimensional electric field models corresponding to a plurality of bubbles, so that the surface electric field intensity distribution of the entire two-phase flow field material can be determined.

[0061] It can be understood that the global surface electric field intensity distribution of the two-phase flow field material includes the surface electric field intensity at the locations where bubbles are adsorbed in the simulation cavity area, and also includes the surface electric field intensity at the locations where bubbles are not adsorbed in the simulation cavity area.

[0062] It should be noted that the embodiment of the present application determines the movement process of bubbles in a two-phase flow field material in an inhomogeneous field, uses the bubble motion control equation to simulate and model the movement process of the bubbles, and establishes a two-dimensional electric field model of the insulating surface of each bubble through the multiple bubbles adsorbed on the surface in the simulated cavity area obtained by modeling. The two-dimensional electric field model is used to determine the surface electric field intensity distribution of the two-phase flow field material, thereby accurately determining the control of the dynamic process of the bubble movement and improving the simulation accuracy of the surface electric field intensity distribution and the evaluation accuracy of the insulation performance.

[0063] In some embodiments, the step S1 determines the bubble motion control equation according to the motion process of the bubble in the two-phase flow field material in the inhomogeneous field, including:

[0064] Step S101, decomposing the movement process of the bubble in the two-phase flow field material in the non-uniform field to obtain multiple movement stages of the bubble movement process; the movement stages include an acceleration stage, a uniform speed stage and a deflection stage.

[0065] Step S102: Analyze the dynamic characteristics of the bubble at each movement stage to obtain the dynamic model of the bubble at each movement stage.

[0066] Among them, 1) Acceleration stage:

[0067] In the initial stage of generation, the bubbles move vertically upward. At this time, the bubbles are far away from the extremely non-uniform electric field and are not considered to be affected by the electric field dielectrophoretic force. The dynamic equation of the bubble movement in the phase change cooling medium is as follows:

[0068]

[0069]

[0070] In the formula, is the bubble mass; t is the time; is the bubble movement speed; It is the viscous resistance, and its direction is opposite to the direction of bubble movement; and are the buoyancy and gravity of the bubble respectively. Among them, the mass of the bubble is:

[0071]

[0072] The buoyancy force on the bubble is:

[0073]

[0074] The drag force on the bubble is:

[0075]

[0076] In the formula, is the bubble radius; is the bubble diameter; and are the gas density and the phase change cooling medium density respectively; is the acceleration due to gravity; is the drag coefficient. The Reynolds number of the bubble will affect the drag coefficient term in the fluid drag. Here is a brief description of the classic formula:

[0077] Reynolds number formula:

[0078]

[0079] In the formula, is the fluid flow velocity; is the dynamic viscosity of the medium.

[0080] when hour,

[0081]

[0082] when hour,

[0083]

[0084] The viscous resistance of the bubble always exists during the entire floating process. Due to the limitation of flow rate, this study only uses the above two empirical formulas. The vertical force in the acceleration stage is:

[0085]

[0086] 2) Constant speed stage

[0087] The bubble rises rapidly in the acceleration phase, and the fluid drag increases accordingly, and after oscillation, it will reach a uniform speed state. In the uniform speed stage, the bubble is affected by buoyancy, gravity, and fluid drag.

[0088] Among them, gravity is several orders of magnitude different from buoyancy and fluid drag, and can be simplified in the derivation process. Under uniform speed, the buoyancy is equal to the drag, and the speed is calculated as:

[0089]

[0090] The formula shows that the square of the bubble velocity is proportional to the bubble diameter. Under the condition of sub-millimeter bubbles and corresponding liquid flow velocity, the velocity range of the bubble after entering the extremely inhomogeneous field is 66-130 mm / s.

[0091] 3) Deflection phase

[0092] The field forces exerted on bubbles in a highly non-uniform electric field mainly include electrophoresis force and dielectrophoresis force.

[0093] Electrophoretic force refers to the Coulomb force on the bubble, which is based on the premise that the bubble is charged. There is no need to charge the bubbles. Due to the inhomogeneity of the field, the Coulomb forces on the equal but opposite charges at both ends of the dipole are different, causing the particles to be affected by the field force under the inhomogeneous electric field. The principle of bubbles in dielectric liquids is the same as that of solid particles in gas environments, and both can be described by the spherical medium model. The dielectrophoretic force on the bubbles can be expressed as:

[0094]

[0095] In the formula, is the electric field strength at the bubble, is the equivalent electric dipole moment of the bubble. For a spherical bubble formed by a uniform isotropic gas, the electric dipole moment can be expressed as:

[0096]

[0097] In the formula, is the bubble volume, is the electric polarization intensity vector, which can be expressed as:

[0098]

[0099] In the formula, is the electric field inside the bubble. The equivalent electric polarization intensity vector after the bubble and the liquid environment are superimposed is:

[0100]

[0101] In the formula, and They represent the relative dielectric constants of the medium outside and inside the sphere, respectively. In an ideal uniform field, the electric field inside the bubble and the ambient electric field strength have the following relationship:

[0102]

[0103] The dielectrophoretic force of a spherical bubble can be expressed as:

[0104]

[0105] The direction of the dielectrophoretic force reflected in the dielectrophoretic force of the spherical bubble is related to the electric field distribution and also depends on the dielectric constant relationship between the medium inside the bubble and the liquid surrounding medium. The dielectric constant of the liquid medium is usually greater than that of the gas. Therefore, under the non-uniform electric field, the bubble moves in the direction of the attenuation of the electric field strength under the action of the dielectrophoretic force. The schematic diagram of the force on the bubble is shown in Figure 3 As shown, fluid drag The direction of the velocity is on the same line as the bubble velocity, but in the opposite direction. represents the flow direction of the flow field, Indicates the possible movement path of bubbles after being affected by a very non-uniform electric field.

[0106] Step S103: Determine the bubble motion control equation using the bubble's dynamics model at each motion stage.

[0107] In the embodiment of the present application, a multiphase flow numerical simulation method based on the finite volume method is used to establish a bubble motion trajectory simulation calculation model, and a fluid flow bubble tracking method is used to track the bubble motion trajectory. In a flowing fluid:

[0108]

[0109] In the formula, is the net force on the bubble; is the position vector of the bubble.

[0110]

[0111]

[0112] The ones used here The drag force expression comes from Stokes drag law.

[0113] Among them, the influence of bubble size, bubble velocity and electric field strength on bubble motion characteristics can be determined through the dynamic model of the bubble at each motion stage. Assuming that the mass of the bubble remains unchanged during the entire motion process, the bubble motion control equation is obtained by combining equations (16)-(19):

[0114]

[0115] In the formula, To find the derivative symbol, is the bubble position vector, For time, and are the gas density and the phase change cooling medium density, is the acceleration due to gravity, is the dynamic viscosity of the medium, is the fluid flow velocity, is the bubble movement speed, is the bubble radius, is the dielectric constant inside the bubble, , represent the relative dielectric constants of the medium outside and inside the sphere, respectively. is the electric field strength at the bubble, and D is the bubble diameter.

[0116] In some embodiments, the step S3 of establishing a two-dimensional electric field model of the insulating surface of each bubble according to the plurality of bubbles adsorbed on the surface of the simulation cavity region in the simulation cavity region includes:

[0117] Step S301 : for each bubble adsorbed on the surface of the simulated cavity region, a tangent line is drawn between the bubble and the surface of the simulated cavity region to obtain a contact angle formed by the tangent line and the surface of the simulated cavity region.

[0118] Among them, the bubbles of the phase change cooling two-phase flow flow through the extremely inhomogeneous field area and are affected by the dielectrophoretic force, and deviate to varying degrees from the strong field area. As the two-phase flow rises, the bubbles will approach or adsorb on the insulating surface, which will affect the insulation of the insulating surface.

[0119] A tangent line is drawn at the contact point between the bubble and the surface (rigid surface) of the simulated cavity area. The angle between the surface of the simulated cavity area and the contact line is the contact angle, such as Figure 4 As shown in Figure 2. According to the Young-Laplace equation, bubbles on oleophobic or hydrophobic surfaces usually have a large contact angle, generally above 90 degrees. The probability of bubbles with small contact angles appearing on oleophobic surfaces in engineering applications is low.

[0120] Step S302: determining a two-dimensional electric field model of the insulating surface of each bubble according to the contact angles, bubble positions and surface electric field strengths corresponding to the plurality of bubbles.

[0121] The surface electric field strength is simulated by establishing a two-dimensional electric field model of the insulating surface of the bubble, and the two-dimensional electric field model of the insulating surface of the bubble includes the contact angle corresponding to each bubble, the bubble position and the surface electric field strength at the position.

[0122] The locations 1, 2, and 3 where the contour lines are densely packed are the weak insulation locations on the insulation surface. Figure 5As shown. When bubbles leave the extremely non-uniform electric field and move to the insulating surface, these positions are more likely to cause insulation degradation. The vertical position is used as a reference, and the effect of surface bubbles on insulation will also be discussed. The bubble contact angle is set to 90°, 120°, 135°, 150°, and 180°. The insulation is set to ceramic material, the liquid environment is fluorocarbon FC-72, and the bubble particle size is 1mm. The lower end of the insulation is defined as 10kV high voltage, and the upper end is grounded. Among them, this simulation does not involve thermal expansion, bubble movement, and electrical stress.

[0123] In some embodiments, determining the surface electric field intensity distribution of the two-phase flow field material according to the two-dimensional electric field models corresponding to the multiple bubbles in step S4 includes:

[0124] Step S401 : fitting is performed according to the two-dimensional electric field models corresponding to the plurality of bubbles, so as to obtain the fitting relationship between the surface electric field intensity, the contact angle and the bubble position.

[0125] By determining the fitting relationship between the surface electric field strength and the contact angle and the bubble position, the surface electric field strength can be determined by the contact angle or the bubble position of the bubble, wherein the fitting relationship between the surface electric field strength and the contact angle and the bubble position is a quadratic function, that is, y=ax 1 2 +bx 2 +c, where y is the surface electric field strength, x 1 、x 2 are the contact angle and bubble position respectively, a, b, c are all constants.

[0126] Step S402: Based on the fitting relationship, the surface electric field intensity distribution of the two-phase flow field material is determined according to the contact angles and bubble positions corresponding to all bubbles adsorbed on the surface of the simulation cavity region in the two-phase flow field material.

[0127] It should be noted that for the position where there is no bubble adsorbed on the surface, the contact angle corresponding to the bubble on the surface of the simulation cavity area is zero, and the bubble position is the current surface position, thereby determining the surface electric field intensity distribution of the two-phase flow field material at the current position.

[0128] In some embodiments, the influence of the contact angle and position on the electric field strength on the insulating surface is determined according to the surface electric field strength simulation results.

[0129] To this end, the method further comprises:

[0130] Step S501, determine the electric field enhancement coefficient according to the surface electric field strength corresponding to each bubble adsorbed on the surface of the simulated cavity area and the surface electric field strength at the corresponding position on the surface of the simulated cavity area when there are no bubbles; wherein the electric field enhancement coefficient is used to characterize the degree to which the bubble enhances the surface electric field strength at different bubble positions and contact angles.

[0131] Step S502: Fitting the electric field enhancement coefficients corresponding to the multiple bubbles to obtain an electric field enhancement coefficient curve.

[0132] For example, through the simulation of the surface electric field strength, the influence of bubbles with contact angles of 180°, 150°, 135°, 120°, and 90° at insulating positions 1, 2, and 3 on the insulating surface field strength is obtained as follows: Figure 6 , 7 , as shown in Figure 8.

[0133] The simulation results show that bubbles will affect the electric field strength on the insulating surface. The ratio of the electric field strength on the insulating surface under the influence of bubbles to the electric field strength on the surface without bubbles is defined as the enhancement coefficient, which is used to characterize the degree of enhancement of the electric field on the insulating surface by bubbles at different positions and contact angles. The enhancement coefficients of the surface electric field under different positions and contact angles are shown in Table 1.

[0134] Table 1 Effect of bubbles on surface electric field strength

[0135]

[0136] As shown in Table 1, bubbles will have a certain degree of influence on insulation when they are at weak insulation positions 1, 2, and 3. The smaller the bubble contact angle, the greater the corresponding enhancement coefficient, that is, the greater the degree of enhancement of the surface electric field strength. When the bubble is in a vertical position, it will have a greater impact on the surface electric field strength relative to the weak insulation position, and the degree of enhancement of the field strength on the insulator surface is about 10%.

[0137] The enhancement coefficient of the surface electric field is fitted according to the bubbles at different positions and contact angles, and the electric field enhancement coefficient curve of the bubbles and the surface electric field is obtained. The electric field enhancement coefficient curve is used to provide inspiration for the insulation design of the phase change cooling valve system. For example, the evacuation path of the bubbles is adjusted by using a reasonable extremely non-uniform field electrical structure, thereby improving the insulation performance of the phase change cooling valve system.

[0138] Based on the same inventive concept, an embodiment of the present application also provides a surface electric field intensity simulation system based on a two-phase flow field for implementing the above-mentioned surface electric field intensity simulation method based on a two-phase flow field.

[0139] The implementation solution to the problem provided by the system is similar to the implementation solution recorded in the above method. Therefore, the specific limitations in one or more embodiments of the surface electric field strength simulation system based on two-phase flow field provided below can be referred to the above limitations on the surface electric field strength simulation method based on two-phase flow field, and will not be repeated here.

[0140] like Fig. 9As shown, the embodiment of the present application provides a surface electric field intensity simulation system based on a two-phase flow field, comprising:

[0141] The bubble motion control module 100 is used to determine the bubble motion control equation according to the motion process of the bubbles in the two-phase flow field material in the inhomogeneous field.

[0142] The simulation modeling module 200 is used to simulate and model the movement process of the bubble according to the bubble movement control equation to obtain a simulation cavity area; wherein the simulation cavity area is used to limit the movement space of the bubble.

[0143] The electric field modeling module 300 is used to establish a two-dimensional electric field model of the insulating surface of each bubble according to a plurality of bubbles adsorbed on the surface of the simulated cavity region in the simulated cavity region.

[0144] The field intensity distribution determination module 400 is used to determine the surface electric field intensity distribution of the two-phase flow field material according to the two-dimensional electric field models corresponding to the multiple bubbles.

[0145] In some embodiments, the bubble motion control module 100 is used to decompose the motion process of the bubble in the two-phase flow field material in the non-uniform field to obtain multiple motion stages of the bubble motion process; the motion stages include an acceleration stage, a uniform speed stage, and a deflection stage;

[0146] The dynamic characteristics of the bubble in each movement stage are analyzed to obtain the dynamic model of the bubble in each movement stage;

[0147] The dynamic model of the bubble at each stage of motion is used to determine the control equation of the bubble motion.

[0148] In some embodiments, the bubble motion governing equation is:

[0149]

[0150] In the formula, To find the derivative symbol, is the bubble position vector, For time, and are the gas density and the phase change cooling medium density, is the acceleration due to gravity, is the dynamic viscosity of the medium, is the fluid flow velocity, is the bubble movement speed, is the bubble radius, is the dielectric constant inside the bubble, , represent the relative dielectric constants of the medium outside and inside the sphere, respectively. is the electric field strength at the bubble, and D is the bubble diameter.

[0151] In some embodiments, the electric field modeling module 300 is used to draw a tangent line between the bubble and the surface of the simulated cavity region for each bubble adsorbed on the surface of the simulated cavity region, and obtain a contact angle formed by the tangent line and the surface of the simulated cavity region;

[0152] A two-dimensional electric field model of the insulating surface of each bubble is determined according to the contact angles corresponding to the multiple bubbles, the bubble positions and the surface electric field strength at the positions.

[0153] In some embodiments, the field intensity distribution determination module 400 is used to perform fitting according to the two-dimensional electric field models corresponding to the multiple bubbles, to obtain the fitting relationship between the surface electric field intensity and the contact angle and the bubble position;

[0154] Based on the fitting relationship, the surface electric field intensity distribution of the two-phase flow field material is determined according to the contact angles and bubble positions corresponding to all bubbles adsorbed on the surface of the simulation cavity area in the two-phase flow field material.

[0155] In some embodiments, the system also includes: an enhanced fitting module, which is used to determine the electric field enhancement coefficient based on the surface electric field strength corresponding to each bubble adsorbed on the surface of the simulated cavity area and the surface electric field strength at the corresponding position on the surface of the simulated cavity area when there are no bubbles; wherein the electric field enhancement coefficient is used to characterize the degree to which the bubble enhances the surface electric field strength at different bubble positions and contact angles; and the electric field enhancement coefficients corresponding to multiple bubbles are fitted to obtain an electric field enhancement coefficient curve.

[0156] like Fig.10 As shown, an embodiment of the present application provides an electronic device, the electronic device 10 includes a memory 20 and a processor 30, the memory 20 stores a computer program, and when the computer program is executed by the processor 30, the processor 30 executes the steps of the surface electric field strength simulation method based on the two-phase flow field in any of the above embodiments.

[0157] An embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed, the steps of the surface electric field intensity simulation method based on the two-phase flow field in any of the above embodiments are implemented.

[0158] An embodiment of the present application provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer executes the steps of the surface electric field strength simulation method in any of the above embodiments.

[0159] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described systems, electronic devices, computer storage media and computer program products can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0160] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising 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 inherent to these processes, methods, products or apparatus.

[0161] In several embodiments provided by the present invention, it is understood that each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and a part of a module, a program segment or a code includes one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved.

[0162] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, electronic devices, computer storage media, computer program products and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0163] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0164] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0165] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for executing all or part of the steps of the method described in each embodiment of the present invention through a computer device (which can be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (full name in English: Read-Only Memory, English abbreviation: ROM), random access memory (full name in English: Random Access Memory, English abbreviation: RAM), disk or optical disk and other media that can store program codes.

[0166] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A surface electric field intensity simulation method based on two-phase flow field, characterized in that: include: According to the movement process of bubbles in the two-phase flow field material in the inhomogeneous field, the bubble movement control equation is determined; The motion process of the bubble is simulated and modeled according to the bubble motion control equation to obtain a simulated cavity area; wherein the simulated cavity area is used to limit the motion space of the bubble; According to a plurality of bubbles adsorbed on the surface of the simulation cavity region in the simulation cavity region, a two-dimensional electric field model of the insulating surface of each bubble is established; The surface electric field intensity distribution of the two-phase flow field material is determined according to the two-dimensional electric field models respectively corresponding to the plurality of bubbles.

2. The surface electric field intensity simulation method based on two-phase flow field according to claim 1 is characterized in that: The bubble motion control equation is determined according to the motion process of the bubbles in the two-phase flow field material in the non-uniform field, including: Decomposing the movement process of bubbles in the two-phase flow field material in the non-uniform field to obtain multiple movement stages of the movement process of the bubbles; the movement stages include an acceleration stage, a uniform speed stage and a deflection stage; Analyzing the dynamic characteristics of the bubble at each movement stage to obtain a dynamic model of the bubble at each movement stage; The bubble motion control equation is determined using the dynamic model of the bubble at each motion stage.

3. The surface electric field intensity simulation method based on two-phase flow field according to claim 1 or 2, characterized in that: The bubble motion control equation is: ； In the formula, To find the derivative symbol, is the bubble position vector, For time, and are the gas density and the phase change cooling medium density, is the acceleration due to gravity, is the dynamic viscosity of the medium, is the fluid flow velocity, is the bubble movement speed, is the bubble radius, is the dielectric constant inside the bubble, , represent the relative dielectric constants of the medium outside and inside the sphere, respectively. is the electric field strength at the bubble, and D is the bubble diameter.

4. The surface electric field intensity simulation method based on two-phase flow field according to claim 1 is characterized in that: The method of establishing a two-dimensional electric field model of the insulating surface of each bubble according to a plurality of bubbles adsorbed on the surface of the simulation cavity region in the simulation cavity region comprises: For each bubble adsorbed on the surface of the simulation cavity region, a tangent line is drawn between the bubble and the surface of the simulation cavity region to obtain a contact angle formed by the tangent line and the surface of the simulation cavity region; A two-dimensional electric field model of the insulating surface of each bubble is determined according to the contact angles, bubble positions and surface electric field strengths corresponding to the plurality of bubbles.

5. The surface electric field intensity simulation method based on two-phase flow field according to claim 4 is characterized in that: The determining the surface electric field intensity distribution of the two-phase flow field material according to the two-dimensional electric field models respectively corresponding to the plurality of bubbles comprises: Performing fitting according to the two-dimensional electric field models respectively corresponding to the plurality of bubbles, to obtain a fitting relationship between the surface electric field strength and the contact angle and the bubble position; Based on the fitting relationship, the surface electric field intensity distribution of the two-phase flow field material is determined according to the contact angles and bubble positions corresponding to all bubbles in the two-phase flow field material adsorbed on the surface of the simulation cavity area.

6. The surface electric field intensity simulation method based on two-phase flow field according to claim 1 is characterized in that: Also includes: The electric field enhancement coefficient is determined according to the surface electric field intensity corresponding to each bubble adsorbed on the surface of the simulated cavity area and the surface electric field intensity at the corresponding position on the surface of the simulated cavity area when there is no bubble; wherein the electric field enhancement coefficient is used to characterize the degree to which the bubble enhances the surface electric field intensity at different bubble positions and contact angles; The electric field enhancement coefficients corresponding to the plurality of bubbles are fitted to obtain an electric field enhancement coefficient curve.

7. A surface electric field strength simulation system based on two-phase flow field, characterized in that: include: A bubble motion control module is used to determine the bubble motion control equation according to the motion process of the bubbles in the two-phase flow field material in the inhomogeneous field; A simulation modeling module, used for performing simulation modeling on the movement process of the bubble according to the bubble movement control equation to obtain a simulation cavity area; wherein the simulation cavity area is used to limit the movement space of the bubble; An electric field modeling module, used for establishing a two-dimensional electric field model of the insulating surface of each bubble according to a plurality of bubbles adsorbed on the surface of the simulation cavity region in the simulation cavity region; The field intensity distribution determination module is used to determine the surface electric field intensity distribution of the two-phase flow field material according to the two-dimensional electric field models corresponding to the multiple bubbles.

8. An electronic device, characterized in that: The electronic device includes a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of the surface electric field strength simulation method based on a two-phase flow field as described in any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the steps of the surface electric field intensity simulation method based on the two-phase flow field as described in any one of claims 1 to 6 are implemented.

10. A computer program product, characterized in that The computer program product includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer is caused to execute the steps of the surface electric field strength simulation method based on a two-phase flow field as described in any one of claims 1-6.

Images