Multi-physics coupling calculation method, device and readable medium for heat pipe stack

Abstract

The present invention provides a multi-physics coupling calculation method, device and readable medium for a heat pipe stack, wherein the method includes: step S1 modeling each component of the heat pipe stack, establishing a heat pipe stack simulation model, a core neutron physics calculation model and a thermal calculation model; step S2 establishing a shared folder; step S3 calculating the core power distribution based on the core neutron physics calculation model and the heat pipe stack simulation model, and outputting the core power distribution to the shared folder; step S4 the thermal calculation model performs core thermal calculation, core mechanics calculation, heat pipe calculation and heat exchanger calculation according to the core power distribution to obtain thermal parameters of the current time step; step S5 judging whether the current time step reaches a preset simulation time, if not, time stepping, and using the thermal parameters of the current time step as input to the core neutron physics calculation model at the next moment; until the preset simulation time is met, outputting the calculation result.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of nuclear reactors, and in particular to a multi-physics coupling calculation method, device and readable medium for a heat pipe stack. Background Art

[0002] The heat pipe-cooled reactor (HPRR) is an innovative reactor solution that differs fundamentally from traditional loop reactors in core structure, cycle power, and heat transfer methods. The HPRR utilizes an all-solid-state core layout. During operation, the fission energy generated in the solid core is transferred to the alkali metal heat pipes within the core, which then transfer heat from the core through internal natural circulation. The heat transfer characteristics of the heat pipes' natural circulation eliminate the need for loop auxiliary systems and pump and valve components in the HPRR's design. These characteristics give the HPRR technical advantages of highly simplified systems, high reliability, and suitability for unmanned operation. It also offers a wide range of potential applications in the field of micro-nuclear power in extreme environments such as deep space, deep sea, and deep earth.

[0003] Numerical simulation of heat pipe reactors (HPHRs) is a key research direction in the development of core HPR technologies. Due to the strong coupling of physical, thermal, and mechanical properties within solid-state HPRs, research into multi-scale, multi-physics coupling is necessary. Existing coupling calculation methods often employ simplified geometric and mathematical models, which pose challenges to computational accuracy and are difficult to address in analyzing the intense physical coupling of multiple components across multiple scales within HPRs.

[0004] Therefore, it is necessary to propose a multi-scale, multi-physics, and multi-component coupling calculation method for heat pipe stacks. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a multi-physics coupling calculation method, device and readable medium for a heat pipe stack, so as to solve the problem that the existing coupling calculation method has low accuracy and is difficult to meet the phenomenon analysis of multi-scale and multi-component strong physical coupling of heat pipe stacks.

[0006] To solve the above technical problems, the present invention provides a multi-physics coupling calculation method for a heat pipe stack, comprising:

[0007] Step S1: Modeling the various components of the heat pipe stack, establishing a heat pipe stack simulation model, a core neutron physics calculation model, and a thermal engineering calculation model;

[0008] Step S2: establishing a shared folder, through which the core neutron physics calculation model and the thermal calculation model transfer parameters;

[0009] Step S3: calculating the core power distribution based on the core neutron physics calculation model and the heat pipe stack simulation model, and outputting the core power distribution to the shared folder;

[0010] Step S4: the thermal calculation model performs core thermal calculation, core mechanical calculation, heat pipe calculation, and heat exchanger calculation according to the core power distribution to obtain thermal parameters for the current time step;

[0011] Step S5: determining whether the current time step reaches the preset simulation time; if not, time stepping forward, and using the thermal parameters of the current time step as input to the core neutron physics calculation model at the next moment;

[0012] Step S6: Repeat steps S3 to S5 until the preset simulation time is met, and output the calculation results, which include the core power distribution, core temperature distribution, core stress and deformation distribution results, heat pipe heat transfer process calculation results, and heat exchanger calculation results.

[0013] Optionally, step S4 includes:

[0014] Step S41: the thermal calculation model performs core thermal calculation according to the core power distribution to obtain the core temperature distribution;

[0015] Step S42: calculating the heat of the heat pipe evaporator wall according to the core temperature distribution, and calculating the heat transfer process of the heat pipe based on the heat of the heat pipe evaporator wall to obtain the calculation result of the heat transfer process of the heat pipe;

[0016] Step S43: performing heat exchanger calculation according to the core temperature distribution to obtain heat exchanger calculation results;

[0017] Step S44: performing core mechanics calculations based on the core temperature distribution to obtain stress and deformation distribution results of the core.

[0018] Optionally, step S41 includes:

[0019] Step S411: Divide each layer of the core structure into a number of control volumes along the axial and radial directions, wherein the cooling channel area can only be divided into control volumes along the axial direction;

[0020] Step S412: Obtain a general control equation for each control body using energy conservation;

[0021] Step S413: Obtain the core temperature distribution according to the general control equation and the core power distribution.

[0022] Optionally, the general control equation is:

[0023]

[0024] Where: i ——density of the control body / kg·m-3; V i——Volume of control body / m3; c pi ——Specific heat capacity of the control body / J·kg-1·K-1; T——temperature; t——time / s; Q in ——The amount of heat introduced into the control body per unit time / W; Q out ——The amount of heat removed from the control body per unit time / W; Q gen ——The heat generated by the heat source in the body per unit time / W.

[0025] Optionally, step S42 includes: using a thermal resistance network model to calculate the heat transfer process of the heat pipe, using the heat exchange conditions of the heat exchanger as boundary conditions, and calculating the temperatures of the evaporation section, the adiabatic section, and the condensation section of the heat pipe.

[0026] Optionally, step S43 includes: performing calculations on the main heat exchanger and the exhaust heat exchanger according to the core temperature distribution to obtain the temperature and flow rate of the heat exchange medium of the main heat exchanger, and the temperature and flow rate of the heat exchange medium of the exhaust heat exchanger.

[0027] Optionally, step S44 includes: calculating stress and deformation distribution results of the core using a matrix radial expansion model, where the matrix radial expansion model is:

[0028]

[0029] Where: ε th — thermal expansion of the substrate; ——The thermal expansion coefficient of the base material at this temperature; ΔT m ——Temperature rise of the substrate.

[0030] Optionally, step S3 includes:

[0031] Step S31: performing neutron steady-state calculations, calculating the core neutron flux using quasi-static equations, and calculating the power spatial distribution of the heat pipe reactor using the neutron fluence rate;

[0032] Step S32: performing neutron transient calculations, introducing a reactivity feedback model and a core decay power model to construct multiple sets of delayed neutron kinetic equations, and using the multiple sets of delayed neutron kinetic equations to describe the change of core power distribution over time.

[0033] Optionally, the multiple sets of delayed neutron kinetic equations are:

[0034]

[0035]

[0036] Where: n is the core fission power / W; t is the time / s; ρ is the total reactivity, including the reactivity of the control rods and various reactivity feedbacks / $; β is the total effective delayed neutron fraction / W; Λ is the neutron generation time / s; λ i ——decay constant of delayed neutrons of group i / s-1; C i ——fission power of the i-th group of delayed neutrons / W; β i ——the fraction of delayed neutrons in group i; n c ——Number of delayed neutron groups.

[0037] Optionally, before step S5, the method further includes:

[0038] Step S50: Determine whether the thermal parameters of the current time step meet the convergence condition. If so, output the thermal parameters of the current time step to the shared folder. The convergence condition is that the deviation of the thermal parameters calculated twice is less than a first threshold.

[0039] Optionally, the thermal calculation model performs core thermal calculation, core mechanical calculation, heat pipe calculation and heat exchanger calculation by a lumped parameter method.

[0040] Optionally, the core neutron physics calculation model and the thermal engineering calculation model transfer parameters by sharing memory.

[0041] To solve the above technical problems, the present invention provides a multi-physics coupling calculation device for a heat pipe stack, comprising: a memory for storing instructions executable by a processor; and a processor for executing the instructions to implement the multi-physics coupling calculation method for a heat pipe stack as described above.

[0042] To solve the above technical problem, the present invention provides a computer-readable medium storing computer program code, which, when executed by a processor, implements the multi-physics coupling calculation method for the heat pipe stack described above.

[0043] Compared with the prior art, the present invention has the following advantages:

[0044] 1. This invention is a coupled calculation method for neutron physics calculation methods and parameter lumping methods. By transferring parameters through shared memory, it fully leverages the computational advantages of neutron physics calculation methods and parameter lumping methods. It also performs thermal-mechanical analysis, heat pipe analysis, and heat exchanger analysis of three-dimensional cores. It can also analyze the phenomenon of strong physical coupling across multiple scales and components in heat pipe reactors, thereby improving the accuracy of multi-physics field coupling calculations in reactors.

[0045] 2. The present invention can not only evaluate the safety of the heat pipe reactor, but also obtain the three-dimensional temperature field distribution and three-dimensional mechanical analysis results at the reactor core scale, thereby enabling a more comprehensive assessment of the operational safety of the heat pipe reactor core.

[0046] 3. The present invention performs three-dimensional refined modeling of the reactor core, solving the problem that the point reactor model cannot take into account the spatial effect of the core, and obtaining simulation calculation results that are more in line with reality. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings are provided to provide a further understanding of the present application. They are included in and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and, together with the description, serve to explain the principles of the present application.

[0048] In the attached figure:

[0049] Figure 1 The flowchart of the multi-physics coupling calculation method of the heat pipe stack according to one embodiment of the present invention is shown.

[0050] Figure 2 4 is a system block diagram of a multi-physics coupling computing device for a heat pipe stack according to an embodiment of the present invention.

[0051] Figure 3 yes Figure 1 Flowchart of an embodiment of step S3 in FIG.

[0052] Figure 4 yes Figure 1 Flowchart of an embodiment of step S4 in FIG.

[0053] Figure 5 yes Figure 4 Flowchart of an embodiment of step S41 in FIG.

[0054] Figure 6 This is a system block diagram of a multi-physics coupling computing device for a heat pipe stack according to another embodiment of the present application. DETAILED DESCRIPTION

[0055] To more clearly illustrate the technical solutions of the embodiments of this application, the following is a brief introduction to the drawings required for describing the embodiments. Obviously, the drawings described below are merely examples or embodiments of this application. Those skilled in the art can apply this application to other similar scenarios based on these drawings without inventive effort. Unless otherwise apparent from the context or otherwise noted, the same reference numerals in the figures represent the same structure or operation.

[0056] The present invention provides a multi-physics coupling calculation method for heat pipe reactors, which can analyze the phenomenon of strong physical coupling of multiple scales and components in heat pipe reactors, give full play to the calculation advantages of core neutron physics calculation method and parameter lumping method, and improve the accuracy of reactor multi-physics field coupling calculation.

[0057] Figure 1FIG. 1 is a flow chart of a multi-physics coupling calculation method for a heat pipe stack according to an embodiment of the present invention. Figure 1 As shown, the multi-physics coupling calculation method 100 for a heat pipe stack includes:

[0058] Step S1: Modeling the various components of the heat pipe stack, establishing a heat pipe stack simulation model, a core neutron physics calculation model, and a thermal engineering calculation model.

[0059] Specifically, each component in the heat pipe stack is modeled, characteristic parameters of each component are set, and a simulation environment is configured. Characteristic parameters include but are not limited to size parameters and material parameters.

[0060] Step S2: Create a shared folder, and the core neutron physics calculation model and the thermal calculation model transfer parameters through the shared folder.

[0061] Figure 2 FIG. 1 is a system block diagram of a multi-physics coupling computing device for a heat pipe stack according to an embodiment of the present invention. Figure 2 As shown, the multi-physics coupling computing device for a heat pipe reactor includes a core neutron physics computing model 11, a shared folder 12, and a thermal engineering computing model 13. The core neutron physics computing model 11 and the thermal engineering computing model 13 transfer parameters via the shared folder 12. The thermal engineering computing model 13 includes a core thermal engineering computing unit 131, a core mechanics computing unit 132, a heat pipe computing unit 133, and a heat exchanger computing unit 134.

[0062] Optionally, the core neutron physics calculation model 11 and the thermal calculation model 13 transmit parameters via shared memory. Shared memory allows two or more processes to access the same memory block. When one process changes the content of the address, the other processes will notice the change.

[0063] Step S3: Calculate the core power distribution based on the core neutron physics calculation model and the heat pipe reactor simulation model, and output the core power distribution to a shared folder.

[0064] Currently, most reactor analysis methods use a point-type model for calculation and analysis of the core. This approximate point-type model fails to account for the spatial effects of the core. Furthermore, due to the complexity of the structure and the necessity of safety analysis, the core requires refined three-dimensional modeling to obtain more accurate core simulation results. The present invention performs three-dimensional refined modeling of the core when establishing a heat pipe reactor simulation model. Therefore, a three-dimensional core simulation model is obtained from the heat pipe reactor simulation model. The core power distribution is calculated based on the three-dimensional core simulation model and the core neutron physics calculation model. Optionally, the core neutron physics calculation model obtains characteristic parameters of each core component from the three-dimensional core, and calculates the core power distribution based on the characteristic parameters of each core component and the core neutron physics calculation method. The present invention performs three-dimensional refined modeling of the reactor core, resolving the problem that the point-type model fails to account for the spatial effects of the core, and obtaining simulation calculation results that are more realistic.

[0065] Three-dimensional core neutron physics calculations mainly include neutron steady-state calculations and neutron transient calculations. By carrying out three-dimensional core simulation models and neutron physics calculations, the three-dimensional spatial distribution and time distribution of core power are obtained. Figure 3 yes Figure 1 Flowchart of step S3 in the embodiment. Figure 3 As shown, step S3 includes:

[0066] Step S31: Perform neutron steady-state calculations, calculate the core neutron flux using a quasi-static equation, and calculate the power spatial distribution of the heat pipe reactor using the neutron flux rate.

[0067] Neutron steady-state calculations are performed by neutron physics calculation programs. Here is a brief introduction to the neutron physics model:

[0068] For k-eigenvalue neutron transport calculations, the quasi-static equation for the core neutron flux is solved as follows:

[0069]

[0070] Where: r is the coordinate vector, Ω is the angular direction, E is the neutron energy, T is the temperature of the material, N is the atomic density of various nuclides in the material, k is the effective multiplication factor, Φ is the angular flux, Σ is the total cross section, Σs is the scattering cross section, νΣf is the neutron production cross section, and χ is the fission spectrum.

[0071] Finally, the neutron fluence rate is used to calculate the spatial distribution of the fission power of the nuclear reactor:

[0072]

[0073] Where: κ is the energy released in each fission.

[0074] The core power size and distribution under steady state, as well as the core neutron parameters, are calculated by the core physics program. In the transient neutron calculation, the spatial distribution of power is assumed to be constant, and the power variation with time is realized by the neutron kinetic equation.

[0075] Step S32: Perform neutron transient calculations, introduce a reactivity feedback model and a core decay power model to construct multiple sets of delayed neutron kinetic equations, and use the multiple sets of delayed neutron kinetic equations to describe the change of core power distribution over time.

[0076] In this embodiment, six sets of delayed neutron kinetic equations are used to describe the change of core power over time, and a reactivity feedback model and a core decay power model are introduced.

[0077] The neutron kinetic equations considering multiple sets of delayed neutrons are used to describe the changes in the core fission power. The reactivity feedback introduced by various feedback effects is also considered. The six sets of delayed neutron kinetic equations can be expressed as follows:

[0078]

[0079]

[0080] Where: n is the core fission power / W; t is the time / s; ρ is the total reactivity, including the reactivity of the control rods and various reactivity feedbacks / $; β is the total effective delayed neutron fraction / W; Λ is the neutron generation time / s; λ is the total effective delayed neutron fraction / W; i ——decay constant of delayed neutrons of group i / s-1; C i ——fission power of the i-th group of delayed neutrons / W; β i ——the fraction of delayed neutrons in group i; n c ——Number of delayed neutron groups.

[0081] Step S4: The thermal calculation model performs core thermal calculation, core mechanical calculation, heat pipe calculation and heat exchanger calculation according to the core power distribution to obtain the thermal parameters of the current time step.

[0082] Optionally, the thermal calculation model performs core thermal calculation, core mechanical calculation, heat pipe calculation and heat exchanger calculation by a lumped parameter method.

[0083] Figure 4 yes Figure 1 Flowchart of step S4 in the embodiment. Figure 4 As shown, step S4 includes:

[0084] Step S41: The thermal calculation model performs core thermal calculation according to the core power distribution to obtain the core temperature distribution.

[0085] The thermal calculation model reads the core power distribution from the shared folder based on the system simulation program with lumped parameters, performs three-dimensional core thermal analysis and calculation based on the core power distribution, and obtains the core temperature distribution through the three-dimensional core thermal analysis and calculation.

[0086] Figure 5 yes Figure 4 Flowchart of step S41 in the embodiment. Figure 5 As shown, step S41 includes:

[0087] Step S411: Divide each layer structure of the core into several control bodies along the axial and radial directions, wherein the cooling channel area can only be divided into control bodies along the axial direction.

[0088] Step S412: Obtain a general control equation for each control body using the law of energy conservation.

[0089] For each control volume i, using the energy conservation principle, the following general control equation can be obtained:

[0090]

[0091] Where: ρ i ——density of the control body / kg·m -3 ; V i ——Volume of control body / m 3 ;c pi ——Specific heat capacity of the control body / J·kg -1 ·K -1 ; T——temperature; t——time / s; Q in ——The amount of heat introduced into the control body per unit time / W; Q out ——The amount of heat removed from the control body per unit time / W; Q gen ——The heat generated by the heat source in the body per unit time / W.

[0092] Step S413: Obtain the core temperature distribution according to the general control equation and the core power distribution.

[0093] Among them, Q in the general control equation in , Q out and Q gen It can be calculated based on the core power distribution. i 、V i 、c pi The temperature of each control body can be calculated based on the characteristic parameters, and the core temperature distribution can be obtained by combining the temperatures of all control bodies.

[0094] Step S42: Calculate the heat of the heat pipe evaporator wall according to the core temperature distribution, calculate the heat transfer process of the heat pipe based on the heat of the heat pipe evaporator wall, and obtain the calculation result of the heat transfer process of the heat pipe.

[0095] When the heat pipe is operating, the evaporation section wall conducts heat, the evaporation section wick and its internal liquid working medium conduct heat and convection, evaporation phase change, vapor axial flow heat transfer, vapor condensation, condensation section wick conduction and convection, and condensation section wall conduction occur in sequence. Optionally, a thermal resistance network model is used to calculate the heat transfer process of the heat pipe. Specifically, the heat transfer process of the heat pipe is calculated based on the heat input from the core to the wall of the heat pipe evaporation section, and the heat exchange conditions set in the heat exchanger module are used as boundary conditions to ultimately calculate the temperatures of the evaporation section, adiabatic section, and condensation section of the heat pipe. That is, the calculation results of the heat transfer process of the heat pipe include but are not limited to the temperatures of the evaporation section, adiabatic section, and condensation section of the heat pipe.

[0096] Step S43: performing heat exchanger calculation according to the core temperature distribution to obtain heat exchanger calculation results.

[0097] Optionally, the heat exchanger calculation results include, but are not limited to, the temperature and flow rate of the main heat exchanger, and the temperature and flow rate of the exhaust heat exchanger. The calculations for the main and exhaust heat exchangers are performed based on the core temperature distribution to obtain the temperature and flow rate of the main and exhaust heat exchangers.

[0098] Step S44: performing core mechanics calculations based on the core temperature distribution to obtain the stress and deformation distribution results of the core.

[0099] In heat pipe reactors, the radial expansion of the matrix and the axial expansion of the fuel caused by the mechanical behavior of the materials are more significant and need to be considered in the reactivity feedback. Alternatively, the stress and deformation distribution results of the core can be calculated using the matrix radial expansion model. The matrix radial expansion model is:

[0100]

[0101] Where: ε th — thermal expansion of the substrate; ——The thermal expansion coefficient of the base material at this temperature; ΔT m ——Temperature rise of the substrate.

[0102] Step S5: determining whether the current time step reaches the preset simulation time; if not, time stepping forward, and using the thermal parameters of the current time step as input to the core neutron physics calculation model at the next moment;

[0103] Step S6: Repeat steps S3 to S5 until the preset simulation time is met, and output the calculation results, which include the core power distribution, core temperature distribution, core stress and deformation distribution results, heat pipe heat transfer process calculation results, and heat exchanger calculation results.

[0104] Optionally, in step S4, the thermal parameters of the current time step are calculated by a numerical algorithm. The thermal parameters include but are not limited to the core temperature distribution, the stress and deformation distribution results of the core, the heat transfer process calculation results of the heat pipe, and the heat exchanger calculation results. Specifically, first, an array is established using the parameter initialization module to discretely initialize each parameter; then the Gear algorithm (Gear method) module is used to iterate and complete the numerical solution. The input is the numerical matrix of the previous moment, and the output is the numerical matrix of the current time step. The Gear method is a numerical method for solving ordinary differential equations. The basic idea of ​​this method is to use the backward Euler method, take the value of the current moment as the unknown quantity, and then use a certain recursive formula to find the value of the next moment.

[0105] Optionally, before step S5, the method further includes:

[0106] Step S50: Determine whether the thermal parameters for the current time step meet the convergence condition. If so, output the thermal parameters for the current time step to a shared folder. The convergence condition is that the deviation between two consecutive thermal parameter calculations is less than a preset threshold. Optionally, the preset threshold is 0.1%. That is, if the deviation between two consecutive thermal parameter calculations is less than 0.1%, the thermal parameters for the current time step are considered to meet the convergence condition, and the thermal parameters for the current time step are output to the shared folder.

[0107] The multi-physics coupling calculation method for the heat pipe pile of the present invention is a coupled calculation method of a neutron physics calculation method and a parameter lumping method. By transferring parameters in a shared memory manner, the calculation advantages of the neutron physics calculation method and the parameter lumping method are fully utilized, and three-dimensional core thermal-mechanical analysis, heat pipe analysis, and heat exchanger analysis are performed. The phenomenon of strong physical coupling of multiple scales and components of the heat pipe pile can be analyzed, thereby improving the accuracy of the multi-physics field coupling calculation of the reactor. The present invention can obtain the three-dimensional temperature field distribution and three-dimensional mechanical analysis results at the scale of the reactor core while evaluating the safety of the heat pipe pile, thereby more comprehensively evaluating the operational safety of the heat pipe pile core.

[0108] The present application also includes a multi-physics coupling calculation device for a heat pipe stack, comprising a memory and a processor, wherein the memory is used to store instructions executable by the processor; the processor is used to execute the instructions to implement the multi-physics coupling calculation method for the heat pipe stack described above.

[0109] Figure 6This is a system block diagram of a multi-physics coupling computing device for a heat pipe stack according to another embodiment of the present invention. Figure 6 As shown, the multi-physics coupling computing device 600 of the heat pipe stack may include an internal communication bus 601, a processor 602, a read-only memory (ROM) 603, a random access memory (RAM) 604, and a communication port 605. When used on a personal computer, the multi-physics coupling computing device 600 of the heat pipe stack may also include a hard disk 606. The internal communication bus 601 enables data communication between the components of the multi-physics coupling computing device 600 of the heat pipe stack. The processor 602 can make judgments and issue prompts. In some embodiments, the processor 602 can be composed of one or more processors. The communication port 605 enables data communication between the multi-physics coupling computing device 600 of the heat pipe stack and the outside world. In some embodiments, the multi-physics coupling computing device 600 of the heat pipe stack can send and receive information and data from the network via the communication port 605. The multi-physics coupled computing device 600 for a heat pipe stack may also include various forms of program storage units and data storage units, such as a hard disk 606, a read-only memory (ROM) 603, and a random access memory (RAM) 604, capable of storing various data files used for computer processing and / or communication, as well as possible program instructions executed by the processor 602. The processor executes these instructions to implement the main part of the method. The results of the processor processing are transmitted to the user device via a communication port and displayed on the user interface.

[0110] The multi-physics coupling calculation method for the heat pipe stack described above may be implemented as a computer program, stored in the hard disk 606 , and loaded into the processor 602 for execution to implement the multi-physics coupling calculation method for the heat pipe stack of the present application.

[0111] The present application also includes a computer-readable medium storing computer program code, which, when executed by a processor, implements the multi-physics coupling calculation method for the heat pipe stack described above.

[0112] When the multi-physics coupling calculation method for a heat pipe stack is implemented as a computer program, it can also be stored in a computer-readable storage medium as a product. For example, a computer-readable storage medium may include, but is not limited to, a magnetic storage device (e.g., a hard disk, a floppy disk, a magnetic strip), an optical disk (e.g., a compact disk (CD), a digital versatile disk (DVD)), a smart card, and a flash memory device (e.g., an electrically erasable programmable read-only memory (EPROM), a card, a stick, a key drive). In addition, the various storage media described herein can represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media (and / or storage media) that can store, contain, and / or carry code and / or instructions and / or data.

[0113] Some aspects of the present application can be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software can be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". The processor can be one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors or combinations thereof. In addition, various aspects of the present application may be expressed as computer products located in one or more computer-readable media, which include computer-readable program code. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, tapes...), optical disks (e.g., compact disks CDs, digital versatile disks DVDs...), smart cards, and flash memory devices (e.g., cards, sticks, key drives...).

[0114] A computer-readable medium may include a propagated data signal embodying computer program code, for example, in baseband or as part of a carrier wave. The propagated signal may be in a variety of forms, including electromagnetic, optical, etc., or a suitable combination thereof. A computer-readable medium may be any computer-readable medium other than a computer-readable storage medium that can be connected to an instruction execution system, apparatus, or device to communicate, propagate, or transmit the program for use. The program code on the computer-readable medium may be transmitted via any suitable medium, including radio, cable, fiber optic cable, radio frequency signal, or similar medium, or any combination of the above.

[0115] Similarly, it should be noted that, in order to simplify the presentation of this application and thus facilitate understanding of one or more embodiments of the invention, the foregoing descriptions of the embodiments of this application sometimes combine multiple features into a single embodiment, figure, or description thereof. However, this disclosure method does not mean that the subject matter of this application requires more features than those recited in the claims. In fact, an embodiment may have fewer features than all of the features of a single embodiment disclosed above.

[0116] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is solely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. Furthermore, while the terms used in this application are selected from commonly known and commonly used terms, some terms mentioned in this specification may have been selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant sections of this description. Furthermore, this application should be understood not only by the actual terms used, but also by the meaning implied by each term.

[0117] Flowcharts are used in this application to illustrate the operations performed by systems according to embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed in exact order. Instead, the various steps may be processed in reverse order or simultaneously. Furthermore, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0118] The basic concepts have been described above. It will be apparent to those skilled in the art that the above disclosures are merely illustrative and do not constitute limitations on this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and amendments to this application. Such modifications, improvements, and amendments are suggested in this application and remain within the spirit and scope of the exemplary embodiments of this application.

[0119] At the same time, this application uses specific terms to describe the embodiments of this application. For example, "one embodiment," "an embodiment," and / or "some embodiments" refer to a certain feature, structure, or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that "one embodiment," "an embodiment," or "an alternative embodiment" mentioned twice or multiple times in different locations in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this application may be appropriately combined.

[0120] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions can be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the scope of the essential spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A multi-physics coupling calculation method for a heat pipe stack, characterized in that: include: Step S1: Modeling the components of the heat pipe stack, establishing a heat pipe stack simulation model, a core neutron physics calculation model, and a thermal engineering calculation model; Step S2: establishing a shared folder, through which the core neutron physics calculation model and the thermal calculation model transfer parameters; Step S3: calculating the core power distribution based on the core neutron physics calculation model and the heat pipe stack simulation model, and outputting the core power distribution to the shared folder; Step S4: the thermal calculation model performs core thermal calculation, core mechanical calculation, heat pipe calculation, and heat exchanger calculation according to the core power distribution to obtain thermal parameters for the current time step; Step S5: determining whether the current time step reaches the preset simulation time; if not, time stepping forward, and using the thermal parameters of the current time step as input to the core neutron physics calculation model at the next moment; Step S6: Repeat steps S3 to S5 until the preset simulation time is met, and output calculation results, which include core power distribution, core temperature distribution, core stress and deformation distribution results, heat pipe heat transfer process calculation results, and heat exchanger calculation results; Wherein, step S4 includes: Step S41: the thermal calculation model performs core thermal calculation according to the core power distribution to obtain the core temperature distribution; Step S42: calculating the heat of the heat pipe evaporator wall according to the core temperature distribution, and calculating the heat transfer process of the heat pipe based on the heat of the heat pipe evaporator wall to obtain the calculation result of the heat transfer process of the heat pipe; Step S43: performing heat exchanger calculation according to the core temperature distribution to obtain heat exchanger calculation results; Step S44: performing core mechanics calculations based on the core temperature distribution to obtain stress and deformation distribution results of the core.

2. The multi-physics coupling calculation method for a heat pipe stack according to claim 1, wherein: Step S41 includes: Step S411: Divide each layer of the core structure into a number of control volumes along the axial and radial directions, wherein the cooling channel area can only be divided into control volumes along the axial direction; Step S412: Obtain a general control equation for each control body using energy conservation; Step S413: Obtain the core temperature distribution according to the general control equation and the core power distribution.

3. The multi-physics coupling calculation method for a heat pipe stack according to claim 2, wherein: The general governing equation is: , in: ——density of control volume / ; ——Volume of control body / ; ——Specific heat capacity of the control body / ; ——temperature; t ——time / s; ——The amount of heat introduced into the control body per unit time / W; ——The amount of heat removed from the control body per unit time / W; ——The amount of heat generated by the heat source in the body per unit time / W.

4. The multi-physics coupling calculation method for a heat pipe stack according to claim 1, wherein: Step S42 includes: using a thermal resistance network model to calculate the heat transfer process of the heat pipe, taking the heat exchange conditions of the heat exchanger as boundary conditions, and calculating the temperatures of the evaporation section, the adiabatic section, and the condensation section of the heat pipe.

5. The multi-physics coupling calculation method for a heat pipe stack according to claim 1, wherein: Step S43 includes: calculating the main heat exchanger and the exhaust heat exchanger according to the core temperature distribution, and obtaining the temperature and flow rate of the heat exchange medium of the main heat exchanger, and the temperature and flow rate of the heat exchange medium of the exhaust heat exchanger.

6. The multi-physics coupling calculation method for a heat pipe stack according to claim 1, wherein: Step S44 includes calculating the stress and deformation distribution results of the core using a matrix radial expansion model, wherein the matrix radial expansion model is: , in: — thermal expansion of the substrate; — coefficient of thermal expansion of the base material at that temperature; —— Temperature rise of the substrate.

7. The multi-physics coupling calculation method for a heat pipe stack according to claim 1, wherein: Step S3 includes: Step S31: performing neutron steady-state calculations, calculating the core neutron flux using a quasi-static equation, and calculating the power spatial distribution of the heat pipe reactor using the neutron fluence rate; Step S32: performing neutron transient calculations, introducing a reactivity feedback model and a core decay power model to construct multiple sets of delayed neutron kinetic equations, and using the multiple sets of delayed neutron kinetic equations to describe the change of core power distribution over time.

8. The multi-physics coupling calculation method for a heat pipe stack according to claim 7, wherein: The multiple sets of delayed neutron kinetic equations are: , in: ——core fission power / W; ——time / s; —Total reactivity, including control rod reactivity and various reactivity feedbacks; ——total effective delayed neutron fraction / W; ——neutron generation time / s; ——decay constant of delayed neutrons of group i / s-1; ——fission power of the i-th group of delayed neutrons / W; ——the fraction of delayed neutrons in group i; ——Number of delayed neutron groups.

9. The multi-physics coupling calculation method for a heat pipe stack according to claim 1, wherein: Before step S5, the method further includes: Step S50: Determine whether the thermal parameters of the current time step meet the convergence condition. If so, output the thermal parameters of the current time step to the shared folder. The convergence condition is that the deviation of the thermal parameters calculated twice is less than a first threshold.

10. The multi-physics coupling calculation method for a heat pipe stack according to any one of claims 1 to 9, characterized in that: The thermal calculation model performs core thermal calculation, core mechanical calculation, heat pipe calculation and heat exchanger calculation by using a lumped parameter method.

11. The multi-physics coupling calculation method for a heat pipe stack according to any one of claims 1 to 9, wherein the core neutron physics calculation model and the thermal engineering calculation model transmit parameters via a shared memory.

12. A multi-physics coupling computing device for a heat pipe stack, characterized in that: include: a memory for storing instructions executable by the processor; A processor, configured to execute the instructions to implement the multi-physics coupling calculation method for a heat pipe stack according to any one of claims 1 to 10. 13 . A computer-readable medium storing computer program codes, wherein when executed by a processor, the computer program codes implement the multi-physics coupling calculation method for a heat pipe stack according to claim 1 .

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