Method, device, equipment, medium and product for determining creep damage of high-temperature component coupled with fatigue damage

Abstract

The application discloses a high-temperature component creep damage determination method and device coupled with fatigue damage, a medium and a product, and relates to the field of high-temperature component safety evaluation. The method comprises the following steps: constructing a cyclic elastic-plastic constitutive model; constructing a high-temperature component finite element model; simulating the cyclic stress-strain and fatigue process of the high-temperature component under a service cyclic load; calculating the fatigue damage of the high-temperature component under a cyclic load spectrum; through the fatigue damage and the creep damage, taking the initial ratchet deformation as the initial deformation of the high-temperature component in the creep damage stage, applying a service temperature field and a service load of the creep damage stage to the high-temperature component, and obtaining the elastic-plastic deformation and the creep deformation of the component in the creep damage stage; constructing a failure criterion and judging whether the component fails. The application can analyze the structure integrity related to the creep of the high-temperature component that has experienced fatigue damage, and prevent the component from failing due to creep.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high-temperature component safety evaluation, and in particular to a high-temperature component creep damage determination method coupled with fatigue damage, device, equipment, medium and product. BACKGROUND

[0002] With the rapid development of industrial technology, the creep failure evaluation of high-temperature components of high-end equipment has attracted more and more attention in the academic and industrial circles. In particular, for high-temperature components that first experience fatigue damage and then experience sustained creep damage, the safety evaluation method is still a technical problem that puzzles the relevant field. Taking nuclear power equipment as an example, if an accident occurs in a nuclear facility, causing radioactive substances to leak, the harm is enormous. In order to prevent and prevent nuclear accidents, the In-Vessel Retention (IVR) technology is used as an important strategy for large advanced pressurized water reactor severe accident management. The reactor adopts IVR mitigation measures under severe accident conditions, which is generally through the cooling of the molten material inside the lower head and the cooling of the outer surface of the lower head. In the presence of external cooling water, the temperature difference between the inner and outer walls of the head is very large, often exceeding 1000℃, thereby causing a large thermal stress on the entire head, and thus the lower head material is prone to severe creep damage. Therefore, considering the fatigue damage of the pressure vessel in the early stage, preventing the creep failure of the pressure vessel over time is a necessary condition to ensure the integrity of the pressure vessel.

[0003] At present, the scheme in the prior art does not record the safety evaluation method for high-temperature components that first experience fatigue damage and then experience sustained creep damage.

[0004] Therefore, how to analyze the structure integrity related to creep of high-temperature components that have experienced fatigue damage and prevent them from occurring creep failure has become a problem to be solved in the field. SUMMARY

[0005] The purpose of the present application is to provide a high-temperature component creep damage determination method coupled with fatigue damage, device, equipment, medium and product, which can analyze the structure integrity related to creep of high-temperature components that have experienced fatigue damage and prevent them from occurring creep failure.

[0006] To achieve the above purpose, the present application provides the following scheme:

[0007] In a first aspect, the present application provides a high-temperature component creep damage determination method coupled with fatigue damage, comprising:

[0008] determining the parameters of a cyclic elastic-plastic constitutive model;

[0009] constructing a cyclic elastic-plastic constitutive model based on the parameters;

[0010] constructing a finite element model of the high-temperature component;

[0011] applying preset boundary conditions and service load spectrum based on the cyclic elastoplastic constitutive model and the finite element model of the high-temperature component, simulating cyclic stress-strain and fatigue process of the high-temperature component under service cyclic load;

[0012] calculating fatigue damage of the high-temperature component under the cyclic load spectrum based on the cyclic stress-strain and fatigue process of the high-temperature component under service cyclic load;

[0013] constructing a creep damage constitutive model coupled with fatigue damage based on the fatigue damage;

[0014] determining creep damage based on the creep damage constitutive model coupled with fatigue damage;

[0015] applying a service temperature field and a service load of a creep damage stage to the high-temperature component by the fatigue damage and the creep damage, taking an initial ratcheting deformation as an initial deformation of the high-temperature component in the creep damage stage, and obtaining elastoplastic deformation and creep deformation of the component in the creep damage stage;

[0016] constructing a failure criterion based on the elastoplastic deformation and the creep deformation;

[0017] judging whether the high-temperature component fails based on the failure criterion.

[0018] Optionally, the cyclic elastoplastic constitutive model has the following expression:

[0019] ε = ε e + ε p

[0020] ε e = D -1 : σ

[0021]

[0022]

[0023] wherein ε is a total strain tensor, ε e is an elastic strain tensor, ε p is a plastic strain tensor, D is an elastic matrix, σ is a stress tensor, F y is a yield criterion, s is a deviatoric stress tensor, α is a back stress tensor, R is an isotropic deformation resistance, is a plastic strain rate, is an equivalent plastic strain rate, J is a second invariant of deviatoric stress, is a tensor in ij component, z is a number of segments of the back stress superposition, k is a cyclic parameter, Ck is the initial hardening modulus, γ k is the rate at which the hardening modulus C k decreases with increasing plastic deformation, ij is each component, α ij is the component of back stress, R0 is the initial yield stress, is the equivalent plastic strain, R ∞ is the maximum change in size of the yield surface, b is the rate at which the size of the yield surface changes with increasing plastic strain.

[0024] Optionally, the determining the parameters of the cyclic elastoplastic constitutive model specifically comprises the following steps:

[0025] obtaining a stress-plastic strain curve of the high-temperature component material;

[0026] dividing the stress-plastic strain curve into three stages according to the curvatures of the stages;

[0027] determining the initial value of the hardening modulus C k according to the slopes of the three stages; wherein k = 1, 2 or 3;

[0028] determining the initial value of γ k based on the initial value of C k ; wherein k = 1, 2 or 3; C k / γ k = σ maxi -R0, wherein σ maxi represents the maximum stress value of each stage, R0 represents the initial yield stress of the material, and γ k is the rate at which the hardening modulus C k decreases with increasing plastic deformation;

[0029] optimizing the initial value of C k and the initial value of γ k to obtain the final C k and γ k .

[0030] Optionally, the calculating the fatigue damage of the high-temperature component under a cyclic load spectrum specifically adopts the following formula:

[0031]

[0032] wherein τ max and σ h,max respectively represent the maximum shear stress and the maximum normal stress in one cycle, Δγ / 2 and Δε / 2 respectively represent the shear strain amplitude and the normal strain amplitude, τ' f , γ' f respectively represent the shear fatigue strength and the shear ductility strength, and σ' fis the fatigue strength constant, ε f is the fatigue ductility coefficient, G represents the shear modulus, b and c represent two exponents related to fatigue strength and ductility, N f is the parameter describing fatigue loss, E represents the elastic modulus, v' represents the Poisson ratio.

[0033] Optionally, the expression of the creep damage constitutive model coupled with fatigue damage is as follows:

[0034]

[0035] wherein, is the component of the creep strain rate, A, n, m are material parameters, ω f is the initial fatigue damage of the material, f(ω f ) is the creep rate amplification factor, σ eq is the equivalent stress, S ij is the deviatoric stress, t is time, ω c is the creep damage.

[0036] Optionally, the failure criterion is constructed based on the elastic-plastic deformation and the creep deformation, and the failure criterion specifically adopts the following formula:

[0037]

[0038] wherein, is the equivalent plastic strain, is the equivalent creep strain, is the plastic fracture strain, is the creep fracture strain, and D is the total damage, and failure occurs when D exceeds 1.

[0039] In a second aspect, the application provides a high-temperature component creep damage determination device coupled with fatigue damage, comprising:

[0040] a parameter determination module configured to determine parameters of a cyclic elastic-plastic constitutive model;

[0041] a cyclic elastic-plastic constitutive model construction module configured to construct a cyclic elastic-plastic constitutive model based on the parameters;

[0042] a finite element model construction module configured to construct a high-temperature component finite element model;

[0043] a cyclic stress-strain and fatigue process simulation module configured to simulate cyclic stress-strain and fatigue processes of a high-temperature component under service cyclic loading based on the cyclic elastic-plastic constitutive model and the high-temperature component finite element model, and by applying a predetermined boundary condition and a service load spectrum;

[0044] a fatigue damage calculation module configured to calculate fatigue damage of the high-temperature component under a cyclic load spectrum based on cyclic stress-strain and fatigue process of the high-temperature component under a service cyclic load;

[0045] a creep damage constitutive model construction module configured to construct a creep damage constitutive model coupled with fatigue damage based on the fatigue damage;

[0046] a creep damage determination module configured to determine creep damage based on the creep damage constitutive model coupled with fatigue damage;

[0047] an elastic-plastic deformation and creep deformation determination module configured to, by the fatigue damage and the creep damage, take an initial ratcheting deformation as an initial deformation of the high-temperature component in a creep damage stage, apply a service temperature field and a service load of the creep damage stage to the high-temperature component, and obtain elastic-plastic deformation and creep deformation of the component in the creep damage stage;

[0048] a failure criterion determination module configured to construct a failure criterion based on the elastic-plastic deformation and the creep deformation;

[0049] a failure judgment module configured to judge whether the high-temperature component fails based on the failure criterion.

[0050] In a third aspect, the present application provides a computer device, comprising: a memory, a processor, a computer program stored in the memory and executable on the processor, and the processor executes the computer program to implement the steps of the creep damage determination method of the high-temperature component coupled with fatigue damage according to any one of the above.

[0051] In a fourth aspect, the present application provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the steps of the creep damage determination method of the high-temperature component coupled with fatigue damage according to any one of the above.

[0052] In a fifth aspect, the present application provides a computer program product, which comprises a computer program, and the computer program is executed by a processor to implement the steps of the creep damage determination method of the high-temperature component coupled with fatigue damage according to any one of the above.

[0053] According to the embodiments provided in the present application, the following technical effects are achieved:

[0054] The application provides a high-temperature component creep damage determination method coupled with fatigue damage, a device, equipment, medium and product, a creep damage constitutive model of a high-temperature component coupled with fatigue damage is established and numerically implemented, meanwhile, a user subroutine and APDL language are secondarily developed in cooperation with a related cyclic constitutive model and a fatigue damage calculation method, continuity and data transmission of the entire numerical simulation process are realized, a complete creep damage analysis process of a high-temperature component coupled with fatigue damage is established, and the structural integrity related to creep of a high-temperature component experiencing fatigue damage can be analyzed to prevent creep failure. BRIEF DESCRIPTION OF DRAWINGS

[0055] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0056] Figure 1 The application environment diagram of a high-temperature component creep damage determination method coupled with fatigue damage in an embodiment of the present application;

[0057] Figure 2 The flowchart of a high-temperature component creep damage determination method coupled with fatigue damage provided by an embodiment of the present application;

[0058] Figure 3 The strain cyclic deformation behavior diagram of a cyclic elastoplastic constitutive model simulation after determining parameters in an embodiment of the present application under 1% strain amplitude at 1100 degrees;

[0059] Figure 4 The fatigue load spectrum diagram applied in an embodiment of the present application;

[0060] Figure 5 The fatigue simulation of three cycles in an embodiment of the present application, (a) is the peak value of the first cycle, and (b) is the peak value of the third cycle;

[0061] Figure 6 The stress-strain curve diagram of a dangerous point under cyclic load in an embodiment of the present application;

[0062] Figure 7 The initial stress diagram obtained by a cyclic elastoplastic model of Chaboche nonlinear follow-up hardening evolution equation and Voce nonlinear isotropic equation in an embodiment of the present application;

[0063] Figure 8The initial strain diagram obtained by the cyclic elastoplastic model of the Chaboche nonlinear follow-up hardening evolution equation and the Voce nonlinear isotropic equation in an embodiment of the present application;

[0064] Figure 9 The creep rate amplification factor distribution diagram of the lower head in an embodiment of the present application;

[0065] Figure 10 The final creep deformation cloud chart of the lower head after 72 hours in an embodiment of the present application, (a) is the creep distribution cloud chart without considering fatigue damage, and (b) is the creep distribution cloud chart coupled with fatigue damage

[0066] Figure 11 The final plastic deformation cloud chart of the lower head after 72 hours in an embodiment of the present application, (a) is the plastic deformation distribution cloud chart without considering fatigue damage, and (b) is the plastic deformation distribution cloud chart coupled with fatigue damage

[0067] Figure 12 The structural schematic diagram of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0068] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0069] In order to make the above purposes, features and advantages of the present application more obvious and understandable, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0070] The creep damage determination method of the high-temperature component coupled with fatigue damage provided in the embodiments of the present application can be applied to, for example Figure 1The application environment shown. Among them, the terminal 102 communicates with the server 104 through the network. The data storage system can store the data required by the server 104 to process. The data storage system can be separately arranged, or integrated on the server 104, or placed on the cloud or other servers. The terminal 102 can send the high-temperature component data to be processed to the server 104, and after receiving the high-temperature component data to be processed, the server 104 first determines the parameters of the cyclic elastic-plastic constitutive model for the high-temperature component data to be processed; construct the cyclic elastic-plastic constitutive model based on the parameters; construct the high-temperature component finite element model; based on the cyclic elastic-plastic constitutive model and the high-temperature component finite element model, apply the preset boundary conditions and service load spectrum, simulate the cyclic stress-strain and fatigue process of the high-temperature component under the service cyclic load; calculate the fatigue damage of the high-temperature component under the cyclic load spectrum based on the cyclic stress-strain and fatigue process of the high-temperature component under the service cyclic load; construct the creep damage constitutive model coupled with fatigue damage based on the fatigue damage; determine the creep damage based on the creep damage constitutive model coupled with fatigue damage; by fatigue damage and creep damage, take the initial ratchet deformation as the initial deformation of the high-temperature component in the creep damage stage, apply the service temperature field and the service load in the creep damage stage to the high-temperature component, and obtain the elastic-plastic deformation and creep deformation of the component in the creep damage stage; construct the failure criterion based on the elastic-plastic deformation and the creep deformation; determine whether the high-temperature component fails based on the failure criterion. The server 104 can feed back the obtained high-temperature component failure result to the terminal 102. In addition, in some embodiments, the high-temperature component creep damage determination method coupled with fatigue damage can also be implemented by the server 104 or the terminal 102 alone, such as being processed by the terminal 102 directly for the high-temperature component data to be processed to obtain the failure result, or being processed by the server 104 to obtain the failure result from the data storage system.

[0071] Among them, the terminal 102 can be but not limited to various desktop computers, notebook computers, smart phones, tablet computers, Internet of Things devices and portable wearable devices, and the Internet of Things devices can be smart speakers, smart televisions, smart air conditioners, smart vehicle devices, etc. The portable wearable device can be a smart watch, a smart bracelet, a head-mounted device, etc. The server 104 can be implemented by an independent server or a server cluster composed of multiple servers, and can also be a cloud server.

[0072] In an exemplary embodiment, as Figure 2 shown, a high-temperature component creep damage determination method coupled with fatigue damage is provided, which is executed by a computer device, specifically can be executed by a terminal or a server alone, or can be executed by a terminal and a server together. In the embodiments of the present application, the method is applied to Figure 1The server 104 in the example is used as an example to illustrate the process, including the following steps 201 to 210. In which:

[0073] Step 201: Determine the parameters of the cyclic elastic-plastic constitutive model.

[0074] Specifically, the stress-plastic strain curve of the material is obtained by processing the experimental single-tension curve, and the stress-plastic strain curve is divided into three stages according to the curvature of each stage, and the C is determined according to the slope of the three stages. k (k=1, 2 or 3), and then calculate γ according to formula (1) k (k=1, 2 or 3) initial value.

[0075] C k / γ k =σ maxi -R0 (1)

[0076] where σ maxi Represents the maximum stress value of each stage, and R0 represents the initial yield stress of the material. Finally, the initial value is optimized through error iteration to obtain the final C k and γ k .

[0077] Step 202: Constructing a cyclic elastic-plastic constitutive model based on the parameters.

[0078] Among them, the cyclic elastic-plastic constitutive model is based on the superposition of Chaboche nonlinear kinematic hardening evolution equation and Voce nonlinear isotropic hardening evolution equation.

[0079] The specific formula is as follows:

[0080] ε=ε e +ε p (2)

[0081] ε e =D -1 :σ(3)

[0082]

[0083] Among them, Formula 6 and Formula 7 are nonlinear kinematic hardening evolution equations, Formula 8 is nonlinear isotropic hardening evolution equation, ε is the total strain tensor, ε e is the elastic strain tensor, ε p is the plastic strain tensor, D is the elastic matrix, σ is the stress tension, F y is the yield criterion, s is the deviatoric stress tensor, α is the back stress tensor, R is the isotropic deformation resistance, is the plastic strain rate, where is the equivalent plastic strain rate, J is the second invariant of the deviatoric stress tensor, is the tensor in the ij component, z is the number of segments for back stress superposition, k is the cyclic parameter, C k is the initial hardening modulus, γ k is the hardening modulus C k decreases at a rate, ij is the component, α ij is the component of back stress, R0 is the initial yield stress, is the equivalent plastic strain, R ∞ and b are material constants, R ∞ is the maximum change of the size of the yield surface, b is the rate of change of the size of the yield surface with increasing plastic strain, which can be obtained by the evolution curve of the response stress amplitude of the material with the cycle number and trial and error method, respectively.

[0084] In this embodiment, taking the steel 16MND5 for the lower head of the pressure vessel as an example, based on the cyclic elastoplastic constitutive model of the superimposed Chaboche nonlinear follow-up hardening evolution equation and Voce nonlinear isotropic hardening evolution equation, the cyclic deformation of the steel 16MND5 for the lower head of the pressure vessel under cyclic load is described, and the corresponding C k and γ k are shown in Table 1. Figure 3 The model simulates the strain cyclic deformation behavior of 16MND5 material at 1100 degrees under a strain amplitude of 1%, and it can be seen that the model can describe the cyclic softening behavior of the 16MND5 material.

[0085] Step 203: constructing a finite element model of the high-temperature component.

[0086] Step 204: based on the cyclic elastoplastic constitutive model and the finite element model of the high-temperature component, applying a predetermined boundary condition and a service load spectrum, simulating the cyclic stress-strain and fatigue process of the high-temperature component under the service cyclic load.

[0087] Based on the secondary development of the large finite element software, the service process of the lower head structure under cyclic load is simulated to obtain the ratchet deformation value and the corresponding equivalent stress amplitude, and at the same time, the fatigue damage model based on the critical plane method is introduced to calculate the fatigue damage of the lower head under the cyclic load spectrum in real time. In this embodiment, the load spectrum of Pmax=50MPa and Pmin=-10MPa (see Figure 4 ) is used to perform three cycles of fatigue simulation, as shown in Figure 5 part (a) of Figure 5 is the peak value of the first cycle, Figure 5The part (b) in the figure is the third cycle peak value. It can be seen that under the cyclic load of Pmax=50 MPa and Pmin=-10 MPa, the peak stress gradually decreases with the cycle, showing the cyclic softening characteristics. At the same time, Figure 6 The stress-strain curve of the dangerous point can be seen that the reverse yield effect is generated under the valley value loading, and the gradually advancing hysteresis loop curve is generated, that is, the ratchet deformation is generated. In the process of the cycle, two aspects of fatigue damage are caused: one is the superposition of the ratchet deformation, and the other is the fatigue damage causing the crack initiation.

[0088] Step 205: fatigue damage of the high-temperature component under the cyclic load spectrum is calculated based on the cyclic stress-strain and fatigue process of the high-temperature component under the service cyclic load.

[0089] The present application adopts the critical plane (SWT) method, considers the contribution of shear strain and normal strain to the total strain damage, and realizes the MGSA fatigue damage model. The method combines the M-C equation to establish the fatigue damage model based on the critical plane method, and realizes the real-time calculation of the fatigue damage of the high-temperature component under the cyclic load spectrum.

[0090] The specific calculation formula is as follows:

[0091]

[0092] Wherein, τ max and σ h,max respectively represent the maximum shear stress and the maximum normal stress in one cycle, Δγ / 2 and Δε / 2 respectively represent the shear strain amplitude and the normal strain amplitude, τ' f , γ' f respectively represent the shear fatigue strength and the shear ductility strength, σ' f is the fatigue strength constant, ε' f is the fatigue ductility coefficient, G represents the shear modulus, b and c represent two indexes about the fatigue strength and ductility, N f is a parameter for describing the fatigue loss, E represents the elastic modulus, and v' represents the Poisson's ratio.

[0093] In the aspect of fatigue prediction of the high-temperature component, the model shows good prediction ability. In the numerical simulation process of fatigue first and then creep, the state variable of the creep subroutine of ANSYS is used to settle and record the initial fatigue damage, and then the fatigue damage value is provided for the creep analysis process.

[0094] Step 206: a creep damage constitutive model coupled with fatigue damage is constructed based on the fatigue damage.

[0095] Based on the component material life creep test, the application establishes the following coupling fatigue damage creep damage constitutive model, and realizes the numerical implementation through the Usercreep user subroutine.

[0096] The specific formula is as follows:

[0097]

[0098] Wherein, is the component of the creep strain rate, A, n, m are all material parameters, which can be obtained according to the creep test on the material with initial fatigue damage, and the correlation of the creep strain evolution and the fatigue damage, ω f is the initial fatigue damage of the material, f(ω f ) is the creep rate amplification factor, σ eq is the equivalent stress, S ij is the deviatoric stress, t is time, ω c is the creep damage.

[0099] Wherein, ω c The evolution equation of the creep damage is:

[0100]

[0101] And are the creep damage rate and the creep strain rate respectively. The multi-axial creep fracture strain, i.e. the multi-axial creep ductility, is different from the uniaxial creep ductility ε f due to the complexity of the stress state in the crack tip region, and the ratio of the multi-axial creep ductility to the uniaxial creep ductility is , which is the multi-axial ductility factor. The MCDF model redefined by Wen-Tu et al. in an exponential form is selected as the multi-axial ductility factor in the application, and the expression is as formula (13):

[0102]

[0103] In order to facilitate engineering application, the model takes ε f as a constant, and σ m is the hydrostatic pressure.

[0104] Step 207: determining the creep damage based on the coupling fatigue damage creep damage constitutive model.

[0105] Based on the component material's full life creep test, the creep damage constitutive model coupled with fatigue damage is established, and the numerical implementation is realized through the Usercreep user subroutine, and the reasonable state variable is set to establish the data and result transmission module between the fatigue service process and the creep service process of the lower head. After completing the fatigue unloading, the temperature field is given to the lower head, considering the influence of high temperature melt, killing the melting unit, at the same time, giving the initial stress and strain field of the lower head creep analysis, the ratchet deformation is transmitted to the creep analysis stage as the initial deformation of the lower head under the IVR condition, at the same time, the fatigue damage formula in the cycle process is transmitted and coupled into the creep damage constitutive model through the state variable, that is, the material's anti-creep performance deterioration caused by fatigue damage is considered in the creep analysis of the lower head.

[0106] Step 208: Through the fatigue damage and creep damage, the initial ratchet deformation is taken as the initial deformation of the high-temperature component in the creep damage stage, the service temperature field and the service load of the creep damage stage are applied to the high-temperature component, and the elastic-plastic deformation and the creep deformation of the component in the creep damage stage are obtained.

[0107] Through the data and result transmission module, the initial ratchet deformation is taken as the initial deformation of the lower head in the creep damage stage, and the initial stress distribution and strain distribution are obtained as shown in Figure 7 and Figure 8 . The service temperature field and the service load of the creep damage stage are applied to the lower head, and through the finite element analysis, the elastic-plastic deformation and the creep deformation of the component in this service stage are obtained, and the creep parameters involved in this stage are listed in Table 1.

[0108] Table 1 Parameters of cyclic constitutive model and creep damage constitutive model at different temperatures

[0109]

[0110]

[0111] Based on the above steps, the creep analysis of the lower head of the pressure vessel is carried out in this embodiment, and the elastic-plastic deformation and the creep deformation of the lower head within 72 hours after the accident are simulated. In this embodiment, the relevant fatigue parameters σ' f is 1500; b is-0.25, and the creep rate amplification factor after material deterioration is calculated. The obtained creep rate amplification factor cloud map is shown in Figure 9 , Figure 10 is the final creep deformation cloud map of the lower head after 72 hours. Among them, Figure 10 part (a) of the lower head 72 hours creep distribution cloud map is not considered fatigue damage, Figure 10Part (b) shows the 72-hour creep distribution cloud of the lower head with coupled fatigue damage. The figure shows that without considering fatigue damage, the maximum creep deformation of the lower head after 72 hours is approximately 0.72%. However, after coupled fatigue damage, the maximum creep deformation of the lower head is approximately 1.62%. This indicates that the creep deformation of the lower head has been significantly increased under the influence of fatigue damage. Figure 11 This is the final plastic deformation cloud diagram of the lower head after 72 hours, where: Figure 11 Part (a) is the 72-hour plastic deformation distribution cloud diagram of the lower head without considering fatigue damage. Figure 11 Part (b) is the 72-hour plastic deformation distribution cloud diagram of the lower head with coupled fatigue damage. It can also be seen that under the influence of fatigue damage, the plastic deformation of the lower head has been enhanced.

[0112] Step 209: constructing a failure criterion based on the elastic-plastic deformation and creep deformation.

[0113] The specific formula is as follows:

[0114]

[0115] in, is the equivalent plastic strain, is the equivalent creep strain, is the plastic fracture strain, is the creep rupture strain, D is the total damage, and failure occurs when D exceeds 1.

[0116] Step 210: Determine whether the high-temperature component has failed based on the failure criterion.

[0117] In this embodiment, the overall damage and failure of the lower head are evaluated and safety assessed based on the established failure criterion of combined elastic-plastic damage and creep deformation damage. In this embodiment, a finite element simulation is performed on the lower head, and the maximum creep strain point A (see Figure 10 ) were analyzed and calculated, and the results are shown in Table 2. It can be seen that under the influence of fatigue damage, the creep strain, plastic strain and total damage parameter D of the lower head have increased significantly.

[0118] Table 2 Final strain and total damage parameter D at point A of the lower head at 72 hours

[0119]

[0120] In summary, the high-temperature component creep analysis method considering fatigue damage provided by the application provides a set of calculation methods considering fatigue damage of high-temperature components in service. A high-temperature component creep damage constitutive model considering fatigue damage is established and numerically implemented. Meanwhile, in combination with a related cyclic constitutive model, a fatigue damage calculation method, a user subroutine and an APDL language secondary development are performed to realize continuity and data transmission of the entire numerical simulation process, and a complete creep analysis process considering fatigue damage of high-temperature components is established.

[0121] Based on the same inventive concept, the embodiments of the application also provide a device for determining the creep damage of a high-temperature component coupled with fatigue damage. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, and therefore the specific limitations in one or more device embodiments for determining the creep damage of a high-temperature component coupled with fatigue damage provided below can be referred to the limitations of the method for determining the creep damage of a high-temperature component coupled with fatigue damage described above, which will not be described here again.

[0122] In an exemplary embodiment, a device for determining the creep damage of a high-temperature component coupled with fatigue damage is provided, comprising:

[0123] a parameter determination module configured to determine parameters of a cyclic elastoplastic constitutive model;

[0124] a cyclic elastoplastic constitutive model construction module configured to construct a cyclic elastoplastic constitutive model based on the parameters;

[0125] a finite element model construction module configured to construct a finite element model of a high-temperature component;

[0126] a cyclic stress-strain and fatigue process simulation module configured to simulate cyclic stress-strain and fatigue processes of the high-temperature component under service cyclic loads based on the cyclic elastoplastic constitutive model and the finite element model of the high-temperature component, by applying preset boundary conditions and service load spectrum;

[0127] a fatigue damage calculation module configured to calculate fatigue damage of the high-temperature component under the cyclic load spectrum based on the cyclic stress-strain and fatigue processes of the high-temperature component under the service cyclic loads;

[0128] a creep damage constitutive model construction module configured to construct a creep damage constitutive model coupled with fatigue damage based on the fatigue damage;

[0129] a creep damage determination module configured to determine the creep damage based on the creep damage constitutive model coupled with fatigue damage;

[0130] an elastic-plastic deformation and creep deformation determination module configured to obtain elastic-plastic deformation and creep deformation of the high-temperature component in the creep damage stage by applying a service temperature field and a service load of the creep damage stage to the high-temperature component, and taking the initial ratcheting deformation as an initial deformation of the high-temperature component in the creep damage stage based on the fatigue damage and the creep damage;

[0131] a failure criterion determination module configured to construct a failure criterion based on the elastic-plastic deformation and the creep deformation;

[0132] a failure judgment module configured to judge whether the high-temperature component fails based on the failure criterion.

[0133] In an exemplary embodiment, a computer device is provided, which can be a server or a terminal, and an internal structure diagram thereof can be as shown in Figure 12 The computer device includes a processor, a memory, an input / output interface (I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The database of the computer device is configured to store high-temperature component safety evaluation data. The input / output interface of the computer device is configured to exchange information between the processor and external devices. The communication interface of the computer device is configured to communicate with external terminals through network connection. The computer program is executed by the processor to implement a high-temperature component creep damage determination method coupled with fatigue damage.

[0134] Those skilled in the art can understand that Figure 12 The structure shown in the above embodiment is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the diagram, or combine certain components, or have a different arrangement of components.

[0135] In an exemplary embodiment, a computer device is provided, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0136] In an exemplary embodiment, a computer readable storage medium is provided, which stores a computer program. The computer program is executed by a processor to implement the steps in the above method embodiments.

[0137] In an example embodiment, a computer program product is provided, including a computer program which, when executed by a processor, implements the steps of any of the above method embodiments.

[0138] It should be noted that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant regulations.

[0139] It can be understood by those skilled in the art that all or part of the processes in the above-mentioned embodiments can be completed by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. Any reference to memory, database or other medium used in the embodiments provided by the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0140] The database involved in the embodiments provided by the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided by the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., without being limited thereto.

[0141] Any technical features in the above embodiments can be combined, and for the sake of brevity, not all possible combinations are described above, however, it should be understood that the application encompasses all possible combinations of the technical features described above.

[0142] The principles and implementation manners of the present application are described herein by using specific examples, and the above embodiments are only used to help understand the method of the present application and its core idea; meanwhile, according to the idea of the present application, the specific implementation manners and application scopes will be changed by those skilled in the art. In conclusion, the content of the present specification should not be understood as a limitation of the present application.

Claims

1. A method for determining creep damage of high-temperature components coupled with fatigue damage, characterized in that: The method for determining creep damage of a high-temperature component coupled with fatigue damage includes: Determine the parameters of the cyclic elastoplastic constitutive model; constructing a cyclic elastoplastic constitutive model based on the parameters; Construct finite element models of high-temperature components; Based on the cyclic elastic-plastic constitutive model and the high-temperature component finite element model, preset boundary conditions and service load spectrum are applied to simulate the cyclic stress-strain and fatigue process of the high-temperature component under service cyclic load; Calculating fatigue damage of the high-temperature component under a cyclic load spectrum based on the cyclic stress-strain and fatigue process of the high-temperature component under service cyclic load; Constructing a creep damage constitutive model coupled with fatigue damage based on the fatigue damage; Determining creep damage based on the creep damage constitutive model of coupled fatigue damage; By using the fatigue damage and creep damage, the initial ratchet deformation is used as the initial deformation of the high-temperature component in the creep damage stage, and the service temperature field and service load of the creep damage stage are applied to the high-temperature component to obtain the elastic-plastic deformation and creep deformation of the component in the creep damage stage; constructing a failure criterion based on the elastic-plastic deformation and creep deformation; Determining whether the high-temperature component has failed based on the failure criterion; The expression of the creep damage constitutive model of coupled fatigue damage is as follows: in, is the component of creep strain rate, A, n, m are all material parameters, ω f is the initial fatigue damage of the material, f(ω f ) is the creep rate magnification factor, σ eq is the equivalent stress, S ij is the deviatoric stress, t is the time, ω c It is creep damage.

2. The method for determining creep damage of high-temperature components coupled with fatigue damage according to claim 1, characterized in that: The expression of the cyclic elastic-plastic constitutive model is as follows: e=e e +e p e e =D -1 :s Where ε is the total strain tensor, ε e is the elastic strain tensor, ε p is the plastic strain tensor, D is the elastic matrix, σ is the stress tension, F y is the yield criterion, s is the deviatoric stress tensor, α is the back stress tensor, R is the isotropic deformation resistance, is the plastic strain rate, is the equivalent plastic strain rate, J is the second invariant of the effect force deviator, is the tensor under the ij component, z is the number of superpositions of back stress, k is the cyclic parameter, C k is the initial kinematic hardening modulus, γ k As the plastic deformation increases, the kinematic hardening modulus C k The rate of decrease, ij is each component, α ij is the component of back stress, R0 is the initial yield stress, is the equivalent plastic strain, R ∞ is the maximum change in the size of the yield surface, and b is the rate of change of the size of the yield surface with the increase of plastic strain.

3. The method for determining creep damage of high-temperature components coupled with fatigue damage according to claim 1, characterized in that: The method of determining the parameters of the cyclic elastic-plastic constitutive model specifically includes the following steps: Obtain stress-plastic strain curves of high-temperature component materials; The stress-plastic strain curve is divided into three stages according to the curvature of each stage; The kinematic hardening modulus C is determined based on the slopes of the three stages. k Initial value of ; where k = 1, 2 or 3; C-based k The initial value of γ is determined k Initial value of; where k = 1, 2 or 3; C k / γ k =σ maxi -R0, where σ maxi represents the maximum stress value in each stage, R0 represents the initial yield stress of the material, γ k As the plastic deformation increases, the kinematic hardening modulus C k rate of decrease; For the C k The initial value and γ k The initial value of C is optimized to obtain the final k and γ k .

4. The method for determining creep damage of a high-temperature component coupled with fatigue damage according to claim 1, characterized in that: The following formula is specifically used to calculate the fatigue damage of high-temperature components under cyclic load spectrum: Among them, τ max and σ h,max They represent the maximum shear stress and maximum normal stress within a cycle, Δγ / 2 and Δε / 2 represent the shear strain amplitude and normal strain amplitude, respectively, τ' f ,γ' f are shear fatigue strength and shear ductility strength, σ' f is the fatigue strength constant, ε' f is the fatigue ductility coefficient, G represents the shear modulus, b and c represent two indices related to fatigue strength and ductility, N f Parameters describing fatigue loss, E represents the elastic modulus, and v′ represents the Poisson's ratio.

5. The method for determining creep damage of a high-temperature component coupled with fatigue damage according to claim 1, characterized in that: The failure criterion constructed based on the elastic-plastic deformation and creep deformation specifically adopts the following formula: in, is the equivalent plastic strain, is the equivalent creep strain, is the plastic fracture strain, is the creep rupture strain, D is the total damage, and failure occurs when D exceeds 1.

6. A device for determining creep damage of high-temperature components coupled with fatigue damage, characterized in that: The device for determining creep damage of a high-temperature component coupled with fatigue damage comprises: A parameter determination module is used to determine the parameters of the cyclic elastic-plastic constitutive model; a cyclic elastic-plastic constitutive model construction module, used for constructing a cyclic elastic-plastic constitutive model based on the parameters; Finite element model building module, used to build finite element models of high-temperature components; A cyclic stress-strain and fatigue process simulation module is used to simulate the cyclic stress-strain and fatigue process of the high-temperature component under service cyclic loads by applying preset boundary conditions and service load spectrum based on the cyclic elastic-plastic constitutive model and the high-temperature component finite element model; a fatigue damage calculation module, configured to calculate fatigue damage of the high-temperature component under a cyclic load spectrum based on the cyclic stress-strain and fatigue process of the high-temperature component under a service cyclic load; A module for constructing a creep damage constitutive model coupled with fatigue damage, for constructing a creep damage constitutive model coupled with fatigue damage based on the fatigue damage; A creep damage determination module, configured to determine creep damage based on the creep damage constitutive model of coupled fatigue damage; an elastic-plastic deformation and creep deformation determination module, configured to use the fatigue damage and creep damage to take the initial ratcheting deformation as the initial deformation of the high-temperature component in the creep damage stage, apply the service temperature field and service load of the creep damage stage to the high-temperature component, and obtain the elastic-plastic deformation and creep deformation of the component in the creep damage stage; a failure criterion determination module, which constructs a failure criterion based on the elastic-plastic deformation and creep deformation; a failure judgment module, configured to judge whether a high-temperature component has failed based on the failure judgment criterion; The expression of the creep damage constitutive model of coupled fatigue damage is as follows: in, is the component of creep strain rate, A, n, m are all material parameters, ω f is the initial fatigue damage of the material, f(ω f ) is the creep rate magnification factor, σ eq is the equivalent stress, S ij is the deviatoric stress, t is the time, ω c It is creep damage.

7. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method for determining creep damage of a high-temperature component coupled with fatigue damage according to any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for determining creep damage of a high-temperature component coupled with fatigue damage according to any one of claims 1 to 5 are implemented.

9. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method for determining creep damage of a high-temperature component coupled with fatigue damage according to any one of claims 1 to 5 are implemented.

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