A mechanical seal performance testing method integrating experimental data and theoretical models

Abstract

The present invention discloses a mechanical seal performance test method integrating test data and theoretical model. The present invention can establish a first theoretical model through the coupling relationship between the relevant equations of the mechanical seal structure, so that the fluid leakage of the mechanical seal structure can be solved by using the finite element method combined with the multiple numerical iteration method, etc., and the influence of the wear amount of the mechanical seal structure on the fluid leakage is introduced through the second theoretical model, and a new boundary condition is provided for the first theoretical model of the next cycle process for iteration, and whether the mechanical seal structure reaches its service life can be judged according to the amount of fluid leakage determined by multiple cycles; through the first theoretical model and the second theoretical model, the service life of the mechanical seal structure and the performance parameters at certain specific moments can be accurately simulated based on the physical factors that the mechanical seal structure is affected by during operation. The present invention is widely used in the field of mechanical seal technology.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical seals, and in particular to a mechanical seal performance testing method integrating test data and theoretical models. Background Art

[0002] Mechanical seal refers to a device that prevents fluid leakage by at least one pair of end faces perpendicular to the axis of rotation, which are kept in contact and slide relative to each other under the action of fluid pressure and the elastic force (or magnetic force) of the compensation mechanism and the cooperation of auxiliary seals. Mechanical seals are often used in various industrial equipment such as liquid pumps, compressors, agitators, stirring equipment, etc., and are suitable for a variety of fluid media, such as water, oil, gas, etc.

[0003] The state of mechanical seals directly affects the performance and life of the equipment. As the working time increases, the mechanical seals gradually wear and age, which seriously affects the reliability of the system. Therefore, understanding the performance of mechanical seals throughout their life cycle can detect possible failures and performance degradation trends of mechanical seals in advance, thereby avoiding unplanned downtime and production interruptions and improving production efficiency. Secondly, it helps to plan maintenance activities, ensure the timing of repairs and replacements of sealing components, maximize the service life of seals, and reduce maintenance costs. In addition, it helps to improve workplace safety, reduce the risk of leakage and accidents, and ensure a safe working environment. Finally, through the full life cycle management of seals, the life of related equipment can be extended, the frequency of equipment replacement and repair can be reduced, and the overall operating cost can be reduced.

[0004] However, the service life of a mechanical seal structure is as long as several thousand hours. It is time-consuming and unrealistic to rely on test equipment to measure the performance of the mechanical seal structure at any period during its life cycle. Summary of the invention

[0005] In view of the technical problems in the current mechanical seal technology, such as the difficulty in measuring the service life of the mechanical seal structure, the object of the present invention is to provide a mechanical seal performance testing method that integrates test data and theoretical models.

[0006] The embodiment of the present invention includes a mechanical seal performance test method integrating test data and theoretical model, and the mechanical seal performance test method integrating test data and theoretical model includes the following steps:

[0007] Establish the first theoretical model;

[0008] Based on the first theoretical model, executing the second theoretical model; executing the second theoretical model for several cycles, calling the first theoretical model in each cycle, and determining the total wear amount according to the execution result of calling the first theoretical model;

[0009] Determining the service life of the mechanical sealing structure by using the second theoretical model;

[0010] The first theoretical model includes the following steps:

[0011] Solving the temperature field distribution of the mechanical seal structure according to the thermal conductivity coefficient of the sealing ring material of the mechanical seal structure;

[0012] Determining the deformation distribution of the sealing ring of the mechanical sealing structure according to the temperature field distribution of the mechanical sealing structure and the Poisson's ratio of the sealing ring;

[0013] Setting an initial liquid film thickness, and solving the liquid film thickness between the sealing end faces of the mechanical seal structure according to the initial liquid film thickness and the deformation distribution of the sealing ring;

[0014] Obtaining the liquid film viscosity of the mechanical seal structure, and solving the end surface liquid film pressure of the mechanical seal structure according to the liquid film thickness between the sealing end surfaces and the liquid film viscosity;

[0015] Acquiring contour boundary parameters of the mechanical seal structure, solving a force balance equation of the mechanical seal structure according to the end surface liquid film pressure and the contour boundary parameters, and obtaining the end surface contact force of the mechanical seal structure;

[0016] The sealing end face leakage and the friction torque are obtained by solving the solution according to the liquid film viscosity, the liquid film thickness between the sealing end faces and the contour boundary parameters.

[0017] Furthermore, any one cycle process in the second theoretical model includes the following steps:

[0018] Solving the temperature field distribution of the mechanical seal structure according to the thermal conductivity coefficient of the sealing ring material of the mechanical seal structure;

[0019] Determining the deformation distribution of the sealing ring of the mechanical sealing structure according to the temperature field distribution of the mechanical sealing structure and the Poisson's ratio of the sealing ring;

[0020] Setting an initial liquid film thickness, and solving the liquid film thickness between the sealing end faces of the mechanical seal structure according to the initial liquid film thickness and the deformation distribution of the sealing ring;

[0021] Obtaining the liquid film viscosity of the mechanical seal structure, and solving the end surface liquid film pressure of the mechanical seal structure according to the liquid film thickness between the sealing end surfaces and the liquid film viscosity;

[0022] Acquire the contour boundary parameters of the mechanical seal structure during this cycle, solve the force balance equation of the mechanical seal structure according to the end surface liquid film pressure and the contour boundary parameters, and obtain the end surface contact force of the mechanical seal structure;

[0023] The sealing end face leakage of the current cycle process is obtained by solving the sealing end face leakage of the current cycle process according to the liquid film viscosity, the liquid film thickness between the sealing end faces and the contour boundary parameters of the current cycle process;

[0024] The accumulated time of each executed cycle process is obtained. When the accumulated value of the sealing end face leakage of each executed cycle process reaches the critical leakage, the service life of the mechanical seal structure is determined according to the accumulated time. Otherwise, the total wear of this cycle process is determined according to the end face contact force and the accumulated time. The contour boundary parameters of the next cycle process are determined according to the total wear, and the execution of the next cycle process is triggered.

[0025] Further, solving the temperature field distribution of the mechanical seal structure according to the thermal conductivity coefficient of the sealing ring material of the mechanical seal structure includes:

[0026] Differential equation for heat conduction

[0027]

[0028] Solve to obtain the temperature field distribution T; where k i is the thermal conductivity coefficient of the sealing ring material, k=1 represents one end face in the mechanical sealing structure, k=2 represents the other end face in the mechanical sealing structure, q is the heat generated by end face friction, r is the radial axis of the plane where the mechanical sealing structure is located, and z is the coordinate axis perpendicular to the plane where the mechanical sealing structure is located;

[0029] The step of solving the deformation distribution of the sealing ring of the mechanical sealing structure according to the temperature field distribution of the mechanical sealing structure and the Poisson's ratio of the sealing ring comprises:

[0030] For the Lame-Navier equation

[0031]

[0032] Solve to obtain the sealing ring deformation distribution δ, where T is the temperature field distribution and v is the sealing ring Poisson's ratio.

[0033] Further, solving the liquid film thickness between the sealing end faces of the mechanical seal structure according to the initial liquid film thickness and the deformation distribution of the sealing ring includes:

[0034] For the equation

[0035] h=h m -δ r -δ s

[0036] Solve to obtain the thickness h of the liquid film between the sealing end faces; where h m is the initial liquid film thickness, δ r is the axial component of the seal ring deformation distribution δ on one end face of the mechanical seal structure, δ s is the axial component of the seal ring deformation distribution δ on the other end surface of the mechanical seal structure.

[0037] Further, solving the end surface liquid film pressure of the mechanical seal structure according to the liquid film thickness between the sealing end surfaces and the liquid film viscosity includes:

[0038] Reynolds equation

[0039]

[0040] Solve to obtain the end surface liquid film pressure p, where h is the liquid film thickness between the sealing end surfaces, and μ is the liquid film viscosity.

[0041] Further, the obtaining of the liquid film viscosity of the mechanical sealing structure includes:

[0042] For the equation

[0043] μ=μ0[αp-β(T-T0)]

[0044] Solve to obtain the liquid film viscosity μ, where μ0 is the fluid injection viscosity, T0 is the fluid injection temperature, α is the viscosity-pressure coefficient, β is the point temperature coefficient, and T is the temperature field distribution.

[0045] Further, solving the force balance equation of the mechanical seal structure according to the end surface liquid film pressure and the contour boundary parameter to obtain the end surface contact force of the mechanical seal structure includes:

[0046] Force balance equation

[0047] F open -F close =0

[0048]

[0049]

[0050] Solve to obtain the end contact force p c ; Among them, r o and r i is the contour boundary parameter, p is the end surface liquid film pressure, p static is the macro contact pressure extracted from the macro finite element model of the mechanical seal structure.

[0051] Further, the sealing end face leakage of the current cycle process is obtained by solving the sealing end face leakage of the current cycle process according to the liquid film viscosity, the liquid film thickness between the sealing end faces and the contour boundary parameters of the current cycle process, including:

[0052] For the equation

[0053]

[0054] Solve to obtain the sealing end face leakage Q i(o) ; Wherein, h is the thickness of the liquid film between the sealing end faces, μ is the viscosity of the liquid film, r i(o) is the contour boundary parameter, and p is the end surface liquid film pressure.

[0055] Further, the total wear amount of the current cycle process is determined according to the end face contact force and the accumulated time, and the contour boundary parameters of the next cycle process are determined according to the total wear amount, including:

[0056] For the equation

[0057]

[0058] y=δ-W

[0059] Solve to obtain the profile deviation y of this cycle process; where W is the total wear amount of this cycle process, k w is the wear rate, p c is the end face contact force, ω is the rotation speed, H is the material yield strength of the mechanical seal structure, t tot is the accumulated time, Δt is the calculation step length of each cycle process that has been executed, and δ is the deformation distribution of the sealing ring.

[0060] Furthermore, the mechanical seal performance testing method integrating the test data with the theoretical model further includes:

[0061] Testing the mechanical seal structure by a first testing device to obtain first test data;

[0062] Testing the mechanical seal structure by a second testing device to obtain second test data;

[0063] Before executing a second theoretical model based on the first theoretical model, modifying the first theoretical model using the first test data;

[0064] Before determining the service life of the mechanical seal structure by using the second theoretical model, the second theoretical model is corrected using the second test data.

[0065] The beneficial effects of the present invention are as follows: the mechanical seal performance testing method integrating test data and theoretical model in the embodiment can establish a first theoretical model through the coupling relationship between the heat conduction equation, thermal deformation equation, end face liquid film lubrication equation, mixed friction heat generation equation and sealing ring force balance equation of the mechanical seal structure, so that the fluid leakage of the mechanical seal structure can be solved by using the finite element method combined with multiple numerical iteration methods, and the influence of the wear amount of the mechanical seal structure on the fluid leakage is introduced through the second theoretical model, so as to provide new boundary conditions for the first theoretical model of the next cycle process for iteration, and it can be judged whether the mechanical seal structure has reached its service life according to the amount of fluid leakage determined by multiple cycles; through the first theoretical model and the second theoretical model, it is possible to accurately simulate the service life of the mechanical seal structure and the performance parameters at certain specific moments based on the physical factors on which the mechanical seal structure is subjected during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 It is a schematic flow chart of a mechanical seal performance testing method integrating test data and theoretical model in an embodiment;

[0067] Figure 2 Schematic diagram of the structure of the dynamic and static rings of the mechanical seal in the embodiment;

[0068] Figure 3 Schematic diagram of the structure of the first test device and the second test device in the embodiment. DETAILED DESCRIPTION

[0069] In this embodiment, refer to Figure 1 The mechanical seal performance test method integrating the test data and the theoretical model includes the following steps:

[0070] S1. Establish the first theoretical model;

[0071] S2. Based on the first theoretical model, establish a second theoretical model;

[0072] S3. Determine the service life of the mechanical seal structure through the second theoretical model.

[0073] In this embodiment, the mechanical seal dynamic and static rings are used as an example of the mechanical seal structure for description, wherein the dynamic ring in the mechanical seal dynamic and static rings is one end surface in the mechanical seal structure, and the static ring in the mechanical seal dynamic and static rings is the other end surface in the mechanical seal structure.

[0074] In step S1, the first theoretical model to be established specifically includes the following equations:

[0075] Heat conduction differential equation

[0076] Lame-Navier equation

[0077] h=h m -δ r -δ s (3)

[0078] Reynolds equation

[0079] μ=μ0[αp-β(T-T0)] (5)

[0080] Force Balance Equation

[0081] F open -F close =0 (6)

[0082]

[0083]

[0084] as well as

[0085]

[0086]

[0087] The first theoretical model uses equations (1)-(10) to perform the following steps:

[0088] S101. Calculate the temperature field distribution of the mechanical seal structure according to the heat conductivity coefficient of the sealing ring material of the mechanical seal structure;

[0089] S102. Determine the deformation distribution of the sealing ring of the mechanical sealing structure according to the temperature field distribution of the mechanical sealing structure and the Poisson's ratio of the sealing ring;

[0090] S103. Setting the initial liquid film thickness, and calculating the liquid film thickness between the sealing end faces of the mechanical seal structure according to the initial liquid film thickness and the deformation distribution of the sealing ring;

[0091] S104. Obtain the liquid film viscosity of the mechanical seal structure, and solve the end surface liquid film pressure of the mechanical seal structure according to the liquid film thickness and liquid film viscosity between the sealing end surfaces;

[0092] S105. Obtaining contour boundary parameters of the mechanical seal structure, solving the force balance equation of the mechanical seal structure according to the end surface liquid film pressure and the contour boundary parameters, and obtaining the end surface contact force of the mechanical seal structure;

[0093] S106. According to the liquid film viscosity, the liquid film thickness between the sealing end faces and the contour boundary parameters, the sealing end face leakage and the friction torque are solved.

[0094] Thermal conductivity k of the sealing ring material in the first theoretical model i , end face friction heat q, sealing ring Poisson's ratio v, fluid injection viscosity μ0, fluid injection temperature T0, viscosity-pressure coefficient α and point temperature coefficient β are parameters that describe the properties of the system medium and sealing material of the dynamic and static rings of the mechanical seal. The values ​​of the above parameters can be set according to experience when establishing the first theoretical model.

[0095] In step S101, the heat conduction differential equation in the first theoretical model, that is, formula (1), can be used:

[0096]

[0097] Solve and obtain the temperature field distribution T. Among them, k i is the thermal conductivity coefficient of the sealing ring material, k=1 represents one end face in the mechanical sealing structure, i.e., the dynamic ring in the dynamic and static rings of the mechanical seal in this embodiment, k=2 represents the other end face in the mechanical sealing structure, i.e., the static ring in the dynamic and static rings of the mechanical seal, and q is the heat generated by end face friction.

[0098] In formula (1), r is the radial axis of the plane where the mechanical seal structure is located, and z is the coordinate axis perpendicular to the plane where the mechanical seal structure is located. Therefore, the heat conduction differential equation is solved in the polar coordinate system. The range of t and z is the boundary condition of formula (1).

[0099] The numerical iteration method can be used to solve formula (1). By solving formula (1), the temperature field distribution T can be obtained, which can be expressed in the form of T = T (r, z), that is, the temperature of each point in the dynamic and static rings of the mechanical seal.

[0100] In step S102, the Lame-Navier equation in the first theoretical model can be used, that is, formula (2):

[0101]

[0102] The deformation distribution of the sealing ring of the mechanical seal structure is obtained by solving the equation (1). Formula (1) represents the influence of the heat generated by the relative movement between the two end faces in the mechanical seal structure on the temperature of the two end faces, while formula (2) represents the influence of the temperature change of the two end faces in the mechanical seal structure on the deformation of the two end faces.

[0103] Formula (2) can be solved by numerical iteration. By solving formula (2), the deformation distribution δ of the sealing ring can be obtained, which can be expressed in the form of δ = δ (r, z), that is, the deformation of each point in the dynamic and static rings of the mechanical seal. Among them, δ is a positive number, indicating that the corresponding end face in the dynamic and static rings of the mechanical seal has expanded and deformed, and δ is a negative number, indicating that the corresponding end face in the dynamic and static rings of the mechanical seal has contracted and deformed.

[0104] In step S103, the following formula (3) can be used in the first theoretical model:

[0105] h=h m -δ r -δ s

[0106] The thickness h of the liquid film between the sealing end faces of the mechanical seal structure is obtained by solving the problem. Among them, the initial liquid film thickness h m Indicates the initial value of the liquid film thickness between the dynamic and static rings of the mechanical seal.

[0107] In formula (3), δ r is the part of the seal ring deformation distribution δ that is axially aligned with one end face of the mechanical seal structure (the moving ring in this embodiment), δ s It is the part of the seal ring deformation distribution δ in the axial direction of the other end face of the mechanical seal structure (the stationary ring in this embodiment). r A positive number indicates that the dynamic ring of the mechanical seal has expanded and deformed. r A negative number indicates that the dynamic ring of the mechanical seal has contracted and deformed. Similarly, δ s A positive number indicates that the static ring of the mechanical seal dynamic and static rings has expanded and deformed. s A negative number indicates that the static ring in the dynamic and static rings of the mechanical seal has shrunk and deformed.

[0108] In step S103, the Reynolds equation in the first theoretical model can be used, that is, formula (4):

[0109]

[0110] Solve and obtain the end surface liquid film pressure p, where μ is the liquid film viscosity.

[0111] When the pressure on the fluid between the end faces increases, the molecular distance decreases and the intermolecular force increases, so the viscosity increases. However, the increase in temperature causes the fluid viscosity to decrease sharply. In the study of thermoelastic flow, the viscosity μ of the liquid film is taken as a function of both pressure and temperature. Therefore, formula (4) uses the exponential form of the liquid film viscosity μ formed by the Barus viscosity-pressure relationship and the Reynolds viscosity-temperature relationship, that is, formula (5) is used in formula (4):

[0112] μ=μ0[αp-β(T-T0)]

[0113] Calculated liquid film viscosity μ.

[0114] In formula (5), μ0 is the fluid injection viscosity of the fluid (water, oil, gas, etc.) between the two end faces of the mechanical seal structure, and T0 is the fluid injection temperature of the liquid between the two end faces of the mechanical seal structure.

[0115] By using the numerical iteration method and boundary conditions used in solving formulas (1) and (2), formula (4) is solved to obtain the end surface liquid film pressure p, which can be expressed in the form of p = p (r, z), that is, the liquid film pressure at each point between the dynamic ring and the static ring of the mechanical seal.

[0116] In step S105, the force balance equation in the first theoretical model, namely, formulas (6), (7) and (8), can be used:

[0117] F open (h m )-F close =0

[0118]

[0119]

[0120] Solve. In the force balance equation, r o and r i is the contour boundary parameter. Specifically, for the dynamic and static rings of the mechanical seal, r o is the outer diameter of the sealing end face, r i is the inner diameter of the sealing end face. F calculated according to formula (7) open The meaning is the opening force of the sealing end face, which is the thickness of the liquid film h m The function of F is calculated according to formula (8): close The meaning is the closing force of the sealing end face. close When using static The meaning is the macro contact pressure. The macro finite element model of the mechanical seal structure (mechanical seal dynamic and static rings) can be established, and the macro contact pressure p can be extracted from the macro finite element model. static Perform calculation according to formula (8).

[0121] Formula (6) means the force balance between the dynamic ring and the static ring in the mechanical seal. By combining formulas (6)-(8), the end contact force p can be calculated by numerical iteration. c .

[0122] In step S106, by formula (9):

[0123]

[0124] Among them, formula (9) actually includes two formulas, namely:

[0125]

[0126]

[0127] and formula (10):

[0128]

[0129] Substitute the data obtained from steps S101-S105 into formula (9) and formula (10) to solve them, so as to obtain the sealing end face leakage Q i(o) And friction torque M. Sealing end face leakage Q i The meaning is: the amount of fluid leakage on the inner diameter of the seal end face due to the wear of the seal end face during the working process of the dynamic and static rings of the mechanical seal simulated by this cycle; the seal end face leakage Q o The meaning is: the fluid leakage of the outer diameter of the seal end face caused by the wear of the seal end face during the simulated working process of the dynamic and static rings of the mechanical seal. The meaning of the friction torque M is the friction torque between the two end faces of the mechanical seal structure (such as the dynamic and static rings of the mechanical seal).

[0130] In this embodiment, before executing step S2 to execute the second theoretical model based on the first theoretical model, a first test device is used to obtain first test data, and the first theoretical model is corrected using the first test data.

[0131] In this embodiment, the first test device used is as follows Figure 3 As shown, it includes a mechanical system, a measurement and control system, and an auxiliary system, which can be used to simulate high pressure, high speed and other working conditions, and measure the first test data. In this embodiment, the measured first test data includes five mechanical seal state parameters: end surface temperature, end surface film thickness, end surface film pressure, friction torque, and leakage.

[0132] In this embodiment, taking the first test device as an example, refer to Figure 3 The mechanical system mainly includes a test chamber, a power and transmission device, and a base. The test chamber is mainly used to install the dynamic and static rings of the mechanical seal and simulate the actual operating conditions of the mechanical seal. The power and transmission device is used to complete the connection between the motor, the rotating shaft and the mechanical seal. The motor is installed on the base to provide power for the test device and is connected to the rotating shaft through a coupling.

[0133] Reference Figure 3 The measurement and control system is mainly composed of an automatic control system and a data acquisition system to realize automatic control of the test device and real-time acquisition and display of various test parameters. The automatic control system uses the PLC controller as the core to realize various operating logic control, automatic fault protection and other functions.

[0134] Reference Figure 3 The control inverter adopts PLC output analog signal and Modbus RTU communication to realize stepless speed regulation of the motor and achieve the purpose of adjustable speed of mechanical seal test.

[0135] Reference Figure 3 The data acquisition system mainly consists of field sensors, signal junction boxes, communication cables, data acquisition cards, etc., which can complete the real-time and accurate reading of various parameters on site.

[0136] Reference Figure 3 ,Both the automatic control system and the data acquisition system realize human-computer interaction through the host computer system; the host computer system is composed of several functional modules, and has the functions of function setting, equipment operation, real-time data display, data processing and storage, and historical data query.

[0137] Reference Figure 3 The auxiliary systems mainly include medium circulation system, medium cooling system and bearing lubrication system. Among them, the low-pressure medium circulation system can complete the medium circulation with a circulation pump, and the high-pressure system completes the medium circulation through the siphon function. The medium cooling system cools the circulating medium to ensure that the fluid medium does not cause excessive temperature due to friction heat during the circulation process, affecting the end face friction state. The bearing lubrication system can achieve bearing lubrication through circulating lubricating oil, spraying oil mist, etc. to ensure the stable operation of the transmission system.

[0138] When testing the mechanical seal structure by the first test device to obtain the first test data, the following steps may be specifically performed:

[0139] P101. Leakage measurement: The leakage is measured by collecting and weighing. Since the leakage is very small, the average leakage is calculated over a long period of time.

[0140] P102. Friction torque measurement: Install a torque sensor between the motor and the power input shaft. By measuring the power input shaft torque minus the friction torque of the main bearing under no-load conditions and the stirring torque generated by the rotating parts of the mechanical seal in the medium under normal pressure in the test chamber, the friction torque of the seal end face can be obtained.

[0141] P103. End surface temperature measurement: To measure the end surface temperature of the mechanical seal using a thermocouple, it is necessary to drill a hole in the static ring from the back, and place several groups of thermocouple sensors at different circumferential directions and depths from the inside to the outside of the static ring. Each group of sensors is installed at different depths in the same radial direction. According to the measured temperature, several groups of T=f(h) relationship equations at different depths can be obtained. According to the sensors placed at the same depth, several groups of T=f(r) relationship equations at different radii can be obtained. The above groups of relationship equations at different radii and depths are subjected to matrix operations and fitting to obtain the T=f(r,h) relationship equation, thereby obtaining the entire temperature field relationship equation;

[0142] P104. End face pressure measurement: MEMS pressure micro sensor is installed on the end face of the mechanical seal static ring through drilling, so as to measure the membrane pressure of the mechanical seal end face;

[0143] P105. End face film thickness measurement, using eddy current method to measure end face film thickness measurement, eddy current sensor to convert mechanical displacement into electrical signal output, with the advantages of large linear range, high sensitivity, fast dynamic response, small structure size, non-contact measurement, no influence of measured medium, etc. The measured material must be a metal conductor, the sensor probe diameter should be less than about 1 / 2 of the measured sealing surface width.

[0144] In this embodiment, before formally executing step S2, several groups of steps identical to steps S101-S106 may be pre-executed. Referring to the principles of steps S101-S106, data such as temperature field distribution, sealing ring deformation distribution, liquid film thickness between sealing end faces, liquid film pressure between end faces, leakage between sealing end faces and friction torque obtained by pre-execution of the first theoretical model may be obtained. These data are respectively compared with the leakage, friction torque, end face temperature, end face pressure and end face film thickness obtained by actually executing steps P101-P105. If the deviation between the theoretical data obtained by pre-execution of the first theoretical model and the actually measured data obtained by executing steps P101-P105 is large (for example, the error is greater than 10%), then the thermal conductivity coefficient k of the sealing ring material in the first theoretical model is adjusted. i , end face friction heat q, sealing ring Poisson's ratio v, fluid injection viscosity μ0, fluid injection temperature T0, viscosity-pressure coefficient α and point temperature coefficient β and other parameters, so as to correct the first theoretical model, and return to compare the theoretical data calculated by the first theoretical model with the measured data again, until the deviation between the theoretical data calculated by the first theoretical model and the measured data is less than the threshold, and the correction of the first theoretical model is completed.

[0145] The completed and revised first theoretical model can provide a correct foundation for the second theoretical model.

[0146] In this embodiment, the second theoretical model to be executed will call the first theoretical model, so the second theoretical model contains all the equations in the first theoretical model, that is, equations (1)-(10). On this basis, the second theoretical model also uses the following equations:

[0147]

[0148] y=δ-W (12)

[0149] That is, the second theoretical model includes equations (1)-(12). Since the first theoretical model has been corrected, when the second theoretical model calls the first theoretical model, the thermal conductivity coefficient k of the sealing ring material used in equations (1)-(10) is i , end face friction heat q, sealing ring Poisson's ratio v, fluid injection viscosity μ0, fluid injection temperature T0, viscosity-pressure coefficient α and point temperature coefficient β are parameters that have been corrected through experiments.

[0150] The wear rate k used in equations (11)-(12) in the second theoretical model is w Parameters such as the material yield strength H of the mechanical seal structure are parameters that describe the properties of the system medium and the sealing material of the dynamic and static rings of the mechanical seal. When establishing the second theoretical model, the values ​​of the above parameters can be set separately according to experience.

[0151] In this embodiment, the process and principle of executing the second theoretical model are as follows: Figure 2 See Figure 2 After executing step S1, establishing the first theoretical model and setting the system medium parameters and sealing material parameters, step S2 is executed. Step S2 includes multiple cycles, and each cycle executes steps S201-S207 once. The steps S201-S207 executed in one cycle (for example, the i-th cycle) are taken as an example for explanation.

[0152] Reference Figure 2 In step S201 of the second theoretical model, the heat conduction differential equation in the first theoretical model is called, that is, formula (1):

[0153]

[0154] Solve and obtain the temperature field distribution T. Among them, k i is the thermal conductivity coefficient of the sealing ring material, k=1 represents one end face in the mechanical sealing structure, i.e., the dynamic ring in the dynamic and static rings of the mechanical seal in this embodiment, k=2 represents the other end face in the mechanical sealing structure, i.e., the static ring in the dynamic and static rings of the mechanical seal, and q is the heat generated by end face friction.

[0155] In formula (1), r is the radial axis of the plane where the mechanical seal structure is located, and z is the coordinate axis perpendicular to the plane where the mechanical seal structure is located. Therefore, the heat conduction differential equation is solved in the polar coordinate system. The range of r and z, i.e., the boundary condition of formula (1), is the range occupied by the dynamic and static rings of the mechanical seal in the polar coordinate system during the current (i-th) cycle, i.e., the contour boundary parameters during the current (i-th) cycle. If the current cycle is the first cycle, then the initial value can be set as the contour boundary parameter, i.e., the boundary condition of formula (1). If the current cycle is not the first cycle, then the contour boundary parameter during the current (i-th) cycle, i.e., the boundary condition of formula (1), is determined by the previous (i-1-th) cycle.

[0156] The numerical iteration method can be used to solve formula (1). By solving formula (1), the temperature field distribution T can be obtained, which can be expressed in the form of T = T (r, z), that is, the temperature of each point in the dynamic and static rings of the mechanical seal.

[0157] Reference Figure 2 In step S202 of the second theoretical model, the Lame-Navier equation in the first theoretical model is called, that is, formula (2):

[0158]

[0159] The deformation distribution of the sealing ring of the mechanical seal structure is obtained by solving the equation (1). Formula (1) represents the influence of the heat generated by the relative movement between the two end faces in the mechanical seal structure on the temperature of the two end faces, while formula (2) represents the influence of the temperature change of the two end faces in the mechanical seal structure on the deformation of the two end faces.

[0160] Formula (2) can be solved by numerical iteration. By solving formula (2), the deformation distribution δ of the sealing ring can be obtained, which can be expressed in the form of δ = δ (r, z), that is, the deformation of each point in the dynamic and static rings of the mechanical seal. Among them, δ is a positive number, indicating that the corresponding end face in the dynamic and static rings of the mechanical seal has expanded and deformed, and δ is a negative number, indicating that the corresponding end face in the dynamic and static rings of the mechanical seal has contracted and deformed.

[0161] Reference Figure 2 In step S203 of the second theoretical model, formula (3) in the first theoretical model is called:

[0162] h=h m -δ r -δ s

[0163] The thickness h of the liquid film between the sealing end faces of the mechanical seal structure is obtained by solving the problem. Among them, the initial liquid film thickness h mIt indicates the initial value of the thickness of the liquid film between the dynamic and static rings of the mechanical seal. If this cycle is the first cycle, the initial setting h can be used when executing this cycle. m If the current cycle is not the first cycle, the end face of the mechanical seal structure is deformed after executing multiple cycles, and the thickness of the liquid film between the two end faces is also changed. Then, after determining the contour boundary parameters of the current cycle (i-th cycle) according to the previous cycle (i-1th cycle), adjust h accordingly according to the change of the contour boundary parameters. m The size of the liquid film between the new sealing end faces is calculated.

[0164] In formula (3), δ r is the part of the seal ring deformation distribution δ that is axially aligned with one end face of the mechanical seal structure (the moving ring in this embodiment), δ s It is the part of the seal ring deformation distribution δ in the axial direction of the other end face of the mechanical seal structure (the stationary ring in this embodiment). r A positive number indicates that the dynamic ring of the mechanical seal has expanded and deformed. r A negative number indicates that the dynamic ring of the mechanical seal has contracted and deformed. Similarly, δ s A positive number indicates that the static ring of the mechanical seal dynamic and static rings has expanded and deformed. s A negative number indicates that the static ring in the dynamic and static rings of the mechanical seal has shrunk and deformed.

[0165] Reference Figure 2 In step S203 of the second theoretical model, the Reynolds equation in the first theoretical model is called, that is, formula (4):

[0166]

[0167] Solve and obtain the end surface liquid film pressure p, where μ is the liquid film viscosity.

[0168] When the pressure on the fluid between the end faces increases, the molecular distance decreases and the intermolecular force increases, so the viscosity increases. However, the increase in temperature causes the fluid viscosity to decrease sharply. In the study of thermoelastic flow, the viscosity μ of the liquid film is taken as a function of both pressure and temperature. Therefore, formula (4) uses the exponential form of the liquid film viscosity μ formed by the Barus viscosity-pressure relationship and the Reynolds viscosity-temperature relationship, that is, formula (5) is used in formula (4):

[0169] μ=μ0[αp-β(T-T0)]

[0170] Calculated liquid film viscosity μ.

[0171] In formula (5), μ0 is the fluid injection viscosity of the fluid (water, oil, gas, etc.) between the two end faces of the mechanical seal structure, and T0 is the fluid injection temperature of the liquid between the two end faces of the mechanical seal structure.

[0172] By using the numerical iteration method and boundary conditions when solving formula (1) and formula (2), formula (4) is solved to obtain the end surface liquid film pressure p, which can be expressed in the form of p = p (r, z), that is, the liquid film pressure at each point between the dynamic ring and the static ring of the mechanical seal.

[0173] Reference Figure 2 In step S205 of the second theoretical model, the force balance equation in the first theoretical model is called, that is, formulas (6), (7) and (8):

[0174] F open (h m )-F close =0

[0175]

[0176]

[0177] Solve. In the force balance equation, r o and r i is the contour boundary parameter. Specifically, for the dynamic and static rings of the mechanical seal, r o is the outer diameter of the sealing end face, r i is the inner diameter of the sealing end face. F calculated according to formula (7) open The meaning is the opening force of the sealing end face, which is the thickness of the liquid film h m The function of F is calculated according to formula (8): close The meaning is the closing force of the sealing end face. close When using static The meaning is the macro contact pressure, refer to Figure 2 , a macroscopic finite element model of the mechanical seal structure (mechanical seal dynamic and static rings) can be established, and the macroscopic contact pressure p can be extracted from the macroscopic finite element model. static Perform calculation according to formula (8).

[0178] Formula (6) means the force balance between the dynamic ring and the static ring in the mechanical seal. By combining formulas (6)-(8), the end contact force p can be calculated by numerical iteration. c .

[0179] Reference Figure 2 In step S206 of the second theoretical model, formula (9) in the first theoretical model is called:

[0180]

[0181] and formula (10):

[0182]

[0183] Substitute the data obtained from steps S201-S205 into formula (9) and formula (10) to solve them, so as to obtain the sealing end face leakage Q of this cycle process: i(o) And friction torque M. The sealing end face leakage Q in this cycle i The meaning is: the fluid leakage of the inner diameter of the sealing end face caused by the wear of the sealing end face during the working process of the dynamic and static rings of the mechanical seal simulated by this cycle process; the sealing end face leakage Q of this cycle process o The meaning is: the fluid leakage of the outer diameter of the seal end face caused by the wear of the seal end face during the working process of the dynamic and static rings of the mechanical seal simulated by this cycle process. The meaning of the friction torque M is the friction torque between the two end faces of the mechanical seal structure (such as the dynamic and static rings of the mechanical seal).

[0184] In formula (9), θ is the other axis of the spatial polar coordinate system where the r axis is located.

[0185] Reference Figure 2 After executing step S206, the sealing end face leakage of this round (i-th round) of the cycle process is obtained. Since the sealing end face leakage of each previously executed round (1st round, 2nd round...i-1th round) of the cycle process is calculated, the sealing end face leakage of each round (from the 1st round to the i-th round) of the cycle process that has been executed is added up to obtain the cumulative value of the sealing end face leakage of each cycle process, which represents the total amount of fluid leakage caused by the wear of the sealing end face during the working process of the dynamic and static rings of the simulated mechanical seal.

[0186] Reference Figure 2, a critical leakage amount can be set, and the cumulative value of the sealing end face leakage amount of each cycle process is compared with the critical leakage amount. If it is greater than or equal to the critical leakage amount, it can be judged that the cumulative value of the sealing end face leakage amount of each cycle process is at a higher level, and correspondingly simulated that the dynamic and static rings of the mechanical seal have reached their service life, then the cycle process can be stopped (that is, the i+1th and subsequent cycle processes are no longer executed, and this round, i.e., the i-th cycle process is the last cycle process), and step S207 is executed to determine the service life of the mechanical seal structure according to the cumulative time of each cycle process that has been executed; if it is less than the critical leakage amount, it can be judged that the cumulative value of the sealing end face leakage amount of each cycle process is at a lower level, and correspondingly simulated that the dynamic and static rings of the mechanical seal have not reached their service life, then the calculation formula attached to the second theoretical model, i.e., formula (11) and formula (12) in this embodiment, is called to calculate the total wear amount of this cycle process and determine the contour boundary parameters of the next cycle process, that is, to update the contour boundary parameters (for example, update the radius r of the dynamic ring o and the radius r of the static ring i , and update the boundary conditions of each equation accordingly), triggering the execution of the next cycle process. During the execution of the next cycle process, the new contour boundary parameters (new boundary conditions) are used to solve equations (1)-(12).

[0187] In this embodiment, a certain calculation step size can be set for each cycle process, for example, the calculation step sizes of the 1st, 2nd, ..., i-1th, and i-th cycle processes are Δt1, Δt2, ..., Δt i-1 , Δt i , the calculation step length can be regarded as the execution time. After the i-th cycle is completed, the cumulative time of each cycle that has been executed is

[0188] t tot =Δt1+Δt2+…+Δt i-1 +Δt i

[0189] Since each cycle simulates the wear process of the mechanical seal structure, each cycle corresponds to the actual time when the mechanical seal structure reaches the corresponding wear degree, such as Δt1, Δt2, ... Δt i-1 , Δt i Corresponding to real time T1, T2...T i-1 , T i , so we can use the accumulated time t tot To determine the service life of the mechanical seal structure, for example, the service life of the mechanical seal structure is determined to be T1+T2+…+T i-1 +T i .

[0190] In this embodiment, if after executing steps S201-S206 of the current round (i-th round) of the loop process, it is determined that the next round (i+1-th round) of the loop process needs to be executed, then reference can be made to Figure 2 , using the additional calculation formulas in the second theoretical model, namely formula (11) and formula (12):

[0191]

[0192] y=δ-W

[0193] Solve and obtain the contour deviation y of this cycle.

[0194] In formula (11), the calculation step lengths of each cycle process can generally be Δt1, Δt2, ... Δt i-1 , Δt i Set to be equal, that is, Δt1 = Δt2 = ... = Δt i-1 =Δt i =Δt, W obtained by solving formula (11) represents the total wear of the mechanical seal structure after executing this cycle.

[0195] In formula (12), by calculating the difference between the deformation distribution δ of the sealing ring of the mechanical sealing structure and the total wear amount W, the profile deviation y obtained represents the position deviation of the end face in the mechanical sealing structure after executing this cycle process relative to the position before any cycle process is started.

[0196] The contour deviation y obtained in this round (i-th round) is superimposed on the r coordinate (for example, superimposed on the radius r of the moving ring). o and the radius r of the static ring i The contour boundary parameters are updated, and the updated contour boundary parameters are used when executing the next round (i+1th round) of the cycle.

[0197] In this embodiment, by executing steps S1-S3, including executing steps S101-S106 and steps S201-S207, a first theoretical model can be established through the coupling relationship between the heat conduction equation, the thermal deformation equation, the end face liquid film lubrication equation, the mixed friction heat generation equation and the sealing ring force balance equation of the mechanical seal structure (mechanical seal dynamic and static ring), so that the fluid leakage of the mechanical seal structure can be solved by using a finite element method combined with a multiple numerical iteration method; when executing the second theoretical model, the second theoretical model calls the first theoretical model to perform calculations, and on this basis, the influence of the wear amount of the mechanical seal structure on the fluid leakage amount is introduced, thereby providing a new boundary condition for the first theoretical model called by the next cycle process to iterate, and it can be judged whether the mechanical seal structure has reached its service life according to the amount of fluid leakage determined by multiple rounds of cycle processes; through the second theoretical model and the first theoretical model called by it, the service life of the mechanical seal structure and the performance parameters at certain specific moments can be accurately simulated based on the physical factors that the mechanical seal structure is subject to during operation.

[0198] In this embodiment, before executing step S3 to determine the service life of the mechanical seal structure by using the second theoretical model, a second test device is used to obtain second test data, and the second theoretical model is corrected using the second test data.

[0199] In this embodiment, the same as the first test device can also be used. Figure 3 The device shown is used as the second test device. The structure of the second test device used can be the same as the first test device, mainly composed of a mechanical system, a measurement and control system, and an auxiliary system. The second test device can also simulate a variety of working conditions, but can only measure friction and leakage as the second test data. The measurement method of the second test device does not destroy the static ring structure of the mechanical seal structure, and the measurement result is authentic.

[0200] In this embodiment, the same steps as steps P1-P5 can be performed to obtain the second test data. Before formally executing step S3, several groups of steps identical to steps S201-S207 can be pre-executed. Referring to the principles of steps S201-S207, the temperature field distribution, sealing ring deformation distribution, liquid film thickness between sealing end faces, liquid film pressure between end faces, leakage between sealing end faces, and friction torque data obtained by the pre-execution of the second theoretical model can be obtained. These data are compared with the leakage, friction torque, end face temperature, end face pressure, and end face film thickness obtained by the actual measurement of steps P101-P105. If the deviation between the theoretical data obtained by the pre-execution of the second theoretical model and the actual measured data obtained by executing steps P101-P105 is large (for example, the error is greater than 10%), then the thermal conductivity coefficient k of the sealing ring material in the second theoretical model is adjusted.i , end face friction heat q, sealing ring Poisson's ratio v, fluid injection viscosity μ0, fluid injection temperature T0, viscosity-pressure coefficient α, point temperature coefficient β, wear rate k w and the material yield strength H of the mechanical seal structure, so as to correct the second theoretical model, and then return to compare the theoretical data calculated by the second theoretical model with the measured data again, until the deviation between the theoretical data calculated by the second theoretical model and the measured data is less than a threshold value, and the correction of the second theoretical model is completed.

[0201] By correcting the second theoretical model, appropriate model parameters can be set for the first theoretical model and the second theoretical model, which is beneficial for more accurately calculating the service life of the mechanical sealing structure when step S3 is formally executed.

[0202] When executing step S3, the modified second theoretical model is used to execute steps S201-S207, thereby predicting the service life of the mechanical sealing structure.

[0203] A computer program that executes the mechanical sealing performance testing method that integrates the test data and the theoretical model in this embodiment can be written and written into a computer device or storage medium. When the computer program is read out and executed, the mechanical sealing performance testing method that integrates the test data and the theoretical model in this embodiment is executed, thereby achieving the same technical effect as the mechanical sealing performance testing method that integrates the test data and the theoretical model in the embodiment.

[0204] It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly fixed or connected to the other feature, or it may be indirectly fixed or connected to the other feature. In addition, the descriptions of up, down, left, right, etc. used in the present disclosure are only relative to the relative positional relationship of the components of the present disclosure in the accompanying drawings. The singular forms of "a", "" and "the" used in the present disclosure are also intended to include the plural forms, unless the context clearly indicates other meanings. In addition, unless otherwise defined, all technical and scientific terms used in this embodiment have the same meaning as those generally understood by those skilled in the art. The terms used in the specification of this embodiment are only for describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in this embodiment includes any combination of one or more related listed items.

[0205] It should be understood that, although the term first, second, third etc. may be adopted to describe various elements in the present disclosure, these elements should not be limited to these terms. These terms are only used to distinguish the same type of elements from each other. For example, without departing from the scope of the present disclosure, the first element may also be referred to as the second element, and similarly, the second element may also be referred to as the first element. The use of any and all examples or exemplary language ("for example", "such as" etc.) provided by the present embodiment is only intended to better illustrate embodiments of the present invention, and unless otherwise required, the scope of the present invention will not be limited.

[0206] It should be appreciated that embodiments of the present invention may be implemented or enforced by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable memory. The method may be implemented in a computer program using standard programming techniques - including a non-transitory computer-readable storage medium configured with a computer program, wherein the storage medium so configured causes the computer to operate in a specific and predefined manner - according to the methods and drawings described in the specific embodiments. Each program may be implemented in a high-level procedural or object-oriented programming language to communicate with a computer system. However, if desired, the program may be implemented in assembly or machine language. In any case, the language may be a compiled or interpreted language. In addition, the program may be run on a programmed dedicated integrated circuit for this purpose.

[0207] In addition, the operations of the process described in this embodiment may be performed in any suitable order, unless otherwise indicated in this embodiment or otherwise clearly contradicted by the context. The process described in this embodiment (or variations and / or combinations thereof) may be performed under the control of one or more computer systems configured with executable instructions, and may be implemented as a code (e.g., executable instructions, one or more computer programs, or one or more applications) executed on one or more processors in common, by hardware or a combination thereof. A computer program includes a plurality of instructions that may be executed by one or more processors.

[0208] Further, the method can be implemented in any type of computing platform that is operably connected to a suitable computer, including but not limited to a personal computer, a minicomputer, a mainframe, a workstation, a network or distributed computing environment, a separate or integrated computer platform, or in communication with a charged particle tool or other imaging device, etc. Various aspects of the present invention can be implemented in machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, an optical read and / or write storage medium, a RAM, a ROM, etc., so that it can be read by a programmable computer, and when the storage medium or device is read by the computer, it can be used to configure and operate the computer to perform the process described herein. In addition, the machine-readable code, or part thereof, can be transmitted via a wired or wireless network. When such media includes instructions or programs that implement the above steps in conjunction with a microprocessor or other data processor, the invention of this embodiment includes these and other different types of non-transitory computer-readable storage media. When programmed according to the methods and techniques of the present invention, the present invention also includes the computer itself.

[0209] The computer program can be applied to input data to perform the functions of the present embodiment, thereby converting the input data to generate output data stored in a non-volatile memory. The output information can also be applied to one or more output devices such as a display. In a preferred embodiment of the present invention, the converted data represents a physical and tangible object, including a specific visual depiction of the physical and tangible object produced on the display.

[0210] The above are only preferred embodiments of the present invention. The present invention is not limited to the above embodiments. As long as the technical effects of the present invention are achieved by the same means, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention. Within the scope of protection of the present invention, its technical solutions and / or implementation methods may have various modifications and changes.

Claims

1. A mechanical seal performance testing method integrating test data and theoretical model, characterized in that: The mechanical seal performance test method integrating test data and theoretical model includes: Establish the first theoretical model; Based on the first theoretical model, executing the second theoretical model; executing the second theoretical model for several cycles, calling the first theoretical model in each cycle, and determining the total wear amount according to the execution result of calling the first theoretical model; Determining the service life of the mechanical seal structure by using the second theoretical model; The first theoretical model includes the following steps: According to the heat conductivity coefficient of the sealing ring material of the mechanical sealing structure, the temperature field distribution of the mechanical sealing structure is solved; Determining the deformation distribution of the sealing ring of the mechanical sealing structure according to the temperature field distribution of the mechanical sealing structure and the Poisson's ratio of the sealing ring; Setting an initial liquid film thickness, and solving the liquid film thickness between the sealing end faces of the mechanical seal structure according to the initial liquid film thickness and the deformation distribution of the sealing ring; Obtaining the liquid film viscosity of the mechanical seal structure, and solving the end surface liquid film pressure of the mechanical seal structure according to the liquid film thickness between the sealing end surfaces and the liquid film viscosity; Acquiring contour boundary parameters of the mechanical seal structure, solving a force balance equation of the mechanical seal structure according to the end surface liquid film pressure and the contour boundary parameters, and obtaining the end surface contact force of the mechanical seal structure; The sealing end face leakage and the friction torque are obtained by solving the solution according to the liquid film viscosity, the liquid film thickness between the sealing end faces and the contour boundary parameters.

2. The mechanical seal performance testing method integrating test data and theoretical model according to claim 1 is characterized in that: Any round of the cycle process in the second theoretical model includes the following steps: Solving the temperature field distribution of the mechanical seal structure according to the thermal conductivity coefficient of the sealing ring material of the mechanical seal structure; Determining the deformation distribution of the sealing ring of the mechanical sealing structure according to the temperature field distribution of the mechanical sealing structure and the Poisson's ratio of the sealing ring; Setting an initial liquid film thickness, and solving the liquid film thickness between the sealing end faces of the mechanical seal structure according to the initial liquid film thickness and the deformation distribution of the sealing ring; Obtaining the liquid film viscosity of the mechanical seal structure, and solving the end surface liquid film pressure of the mechanical seal structure according to the liquid film thickness between the sealing end surfaces and the liquid film viscosity; Acquire the contour boundary parameters of the mechanical seal structure during this cycle, solve the force balance equation of the mechanical seal structure according to the end surface liquid film pressure and the contour boundary parameters, and obtain the end surface contact force of the mechanical seal structure; The sealing end face leakage of the current cycle process is obtained by solving the sealing end face leakage of the current cycle process according to the liquid film viscosity, the liquid film thickness between the sealing end faces and the contour boundary parameters of the current cycle process; The accumulated time of each executed cycle process is obtained. When the accumulated value of the sealing end face leakage of each executed cycle process reaches the critical leakage, the service life of the mechanical seal structure is determined according to the accumulated time. Otherwise, the total wear of this cycle process is determined according to the end face contact force and the accumulated time. The contour boundary parameters of the next cycle process are determined according to the total wear, and the execution of the next cycle process is triggered.

3. The mechanical seal performance testing method integrating experimental data and theoretical model according to claim 2 is characterized in that: The step of solving the temperature field distribution of the mechanical seal structure according to the heat conductivity coefficient of the sealing ring material of the mechanical seal structure comprises: Differential equation for heat conduction Solve to obtain the temperature field distribution ;in, is the thermal conductivity coefficient of the sealing ring material, represents an end face in the mechanical seal structure, represents another end face in the mechanical seal structure, The end surface friction generates heat. is the radial coordinate of the plane where the mechanical seal structure is located, is the coordinate of the coordinate axis perpendicular to the plane where the mechanical seal structure is located; The step of solving the deformation distribution of the sealing ring of the mechanical sealing structure according to the temperature field distribution of the mechanical sealing structure and the Poisson's ratio of the sealing ring comprises: For the Lame-Navier equation Solve to obtain the deformation distribution of the sealing ring ;in, is the temperature field distribution, is the Poisson's ratio of the sealing ring.

4. The mechanical seal performance testing method integrating test data and theoretical model according to claim 3 is characterized in that: The step of solving the liquid film thickness between the sealing end faces of the mechanical seal structure according to the initial liquid film thickness and the deformation distribution of the sealing ring includes: For the equation Solve to obtain the thickness of the liquid film between the sealing end faces ;in, is the initial liquid film thickness, The deformation distribution of the sealing ring The axial component at one end face of the mechanical seal structure, The deformation distribution of the sealing ring The axial component at the other end surface of the mechanical seal structure.

5. The mechanical seal performance testing method integrating test data and theoretical model according to claim 4 is characterized in that: The step of solving the end surface liquid film pressure of the mechanical seal structure according to the liquid film thickness between the sealing end surfaces and the liquid film viscosity comprises: Reynolds equation Solve to obtain the end surface liquid film pressure ;in, is the thickness of the liquid film between the sealing end faces, is the liquid film viscosity.

6. The mechanical seal performance testing method integrating test data and theoretical model according to claim 5 is characterized in that: The step of obtaining the liquid film viscosity of the mechanical sealing structure comprises: For the equation Solve to obtain the liquid film viscosity ;in, Introducing viscosity into the fluid, Injection temperature for the fluid, is the viscosity-pressure coefficient, is the point temperature coefficient, is the temperature field distribution.

7. The mechanical seal performance testing method integrating test data and theoretical model according to claim 5 is characterized in that: The step of solving the force balance equation of the mechanical seal structure according to the end surface liquid film pressure and the contour boundary parameter to obtain the end surface contact force of the mechanical seal structure comprises: Force balance equation Solve to obtain the end contact force ;in, is the opening force of the sealing end face, is the closing force of the sealing end face, is the outer diameter of the sealing end face, is the inner diameter of the sealing face, is the end surface liquid film pressure, is the macro contact pressure extracted from the macro finite element model of the mechanical seal structure.

8. The mechanical seal performance testing method integrating test data and theoretical model according to claim 7 is characterized in that: The method of solving the sealing end face leakage of the current cycle process according to the liquid film viscosity, the liquid film thickness between the sealing end faces and the contour boundary parameters of the current cycle process comprises: For the equation Solve to obtain the sealing end face leakage ;in, yes The other axis of the polar coordinate system of the space where the axis is located, is the thickness of the liquid film between the sealing end faces, The liquid film viscosity, is the contour boundary parameter, is the end surface liquid film pressure.

9. The mechanical seal performance testing method integrating test data and theoretical model according to claim 8, characterized in that: Determining the total wear amount of the current cycle process according to the end face contact force and the accumulated time, and determining the contour boundary parameters of the next cycle process according to the total wear amount, includes: For the equation Solve and obtain the contour deviation of this cycle process ;in, is the total wear amount in this cycle, is the wear rate, is the end contact force, is the rotation speed, is the material yield strength of the mechanical seal structure, is the cumulative time, is the calculation step length of each cycle process that has been executed, is the deformation distribution of the sealing ring.

10. The mechanical seal performance testing method integrating test data and theoretical model according to any one of claims 1 to 9, characterized in that: The mechanical seal performance testing method integrating test data and theoretical model also includes: Testing the mechanical seal structure by a first testing device to obtain first test data; Testing the mechanical seal structure by a second testing device to obtain second test data; Before executing a second theoretical model based on the first theoretical model, modifying the first theoretical model using the first test data; Before determining the service life of the mechanical seal structure by using the second theoretical model, the second theoretical model is corrected using the second test data.

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