Thermal component solid heat conduction equation parallel computing device and method suitable for Modelica specification

Abstract

The invention belongs to the technical field of thermal hydraulic power, and particularly relates to a thermal component solid heat conduction equation parallel computing device and method suitable for Modelica specifications. Comprising a thermal hydraulic system topological structure generation module, a data container configuration module, a data container retrieval positioning and data mapping module, a generalized source term function calculation process and task scheduling module and a data container-based solid heat conduction equation multi-segment parallel solving module, a thermal hydraulic source term function multi-node unit parallel computing module based on the data container; and a two-fluid six-equation system single-step solving module. The method has the beneficial effects that the solving calculation efficiency of coupling the thermal hydraulic model with the thermal component model, such as a reactor core model, a pipeline model with a thermal component, a container model with a thermal component, a heat exchanger model and the like, can be effectively improved, so that the calculation efficiency of the thermal hydraulic system model based on Modelica is improved; technical support is provided for rapid design verification of a thermal hydraulic system and real-time simulation of a digital twin model.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal hydraulics, and in particular relates to a device and method for parallel calculation of solid heat conduction equations of thermal components applicable to Modelica specifications. Background Art

[0002] The Modelica-based modeling and simulation of thermal-hydraulic systems involves a significant amount of solid heat conduction, including heat release from reactor core fuel rods, heat transfer from heat exchanger tubes, heat generation from container electric heating elements, and heat dissipation from pipe walls. These solid heat conductions are typically modeled using thermal component models. During thermal component modeling, the temperature gradient along the flow direction (usually axial) is significantly smaller than the temperature gradient along the solid wall (usually radial). Axial heat transfer can be neglected, and heat transfer is assumed to occur only in the radial direction. Furthermore, the thermal component model is connected to the thermal-hydraulic model via a thermal interface, transferring parameters such as heat flux and wall temperature across the solid wall. In order to ensure the consistency of parameter transfer between the thermal component model and the thermal fluid model, the node division form of the thermal component model and the thermal-hydraulic model along the axial direction is required to be consistent, so that one axial node of the thermal component corresponds to one thermal-hydraulic control body, and a one-dimensional solid heat conduction equation along the radial direction is constructed in each axial node of the thermal component. There is no constraint relationship between the solid heat conduction equations of each axial node of the thermal component. This provides the conditions for parallel calculation of the solid heat conduction equation of the thermal component based on multiple axial nodes. Summary of the Invention

[0003] The purpose of the present invention is to provide a parallel calculation device and method for the solid heat conduction equation of thermal components applicable to the Modelica specification, which can effectively improve the solution and calculation efficiency of thermal hydraulic models coupled with thermal component models, such as: reactor core models, pipeline models with thermal components, container models with thermal components, heat exchanger models, etc., thereby improving the calculation efficiency of thermal hydraulic system models based on Modelica, and providing technical support for rapid design and verification of thermal hydraulic systems and real-time simulation of digital twin models.

[0004] The technical solution of the present invention is as follows: a parallel calculation method for the solid heat conduction equation of a thermal component applicable to the Modelica specification, comprising the following steps:

[0005] Step 1: In the Modelica-based thermal-hydraulic system model, traverse the thermal component model and establish the corresponding connection relationship between the thermal component model and the thermal-hydraulic model components through the thermal interface connection information of the thermal component model;

[0006] Step 2: Flatten the thermal component model and its corresponding thermal-hydraulic model components according to their discrete node partitioning method. Convert the thermal-hydraulic model components into a model consisting of an interlaced and orderly connection of control body models and nozzle models. Furthermore, convert the thermal component model into a collection of thermal component node models that correspond one-to-one to the thermal-hydraulic control body models.

[0007] Step 3: Flatten the model components in the thermal-hydraulic system model that are not connected to the thermal components. Connect the flattened thermal-hydraulic model through flow interfaces, and convert the thermal-hydraulic system model into a flattened system model that is sequentially connected by the control body model, the pipe model, and the thermal component node model. The control body model and the pipe model are staggeredly connected through flow interfaces, and the thermal component node model is connected to the control body model through a thermal interface on one side. The thermal component node model corresponds one-to-one with the control body model.

[0008] Step 4: Sequentially number the control body model, takeover model, and thermal component node model of the flattened system model, and configure a data container for each control body model, takeover model, and thermal component node model in the memory space;

[0009] Step 5: Traverse the thermal component node data container, and according to the control body number of the internal or external thermal interface connection information of the data container, retrieve and locate the data container of the control body model connected to the internal or external thermal interface of the thermal component node, establish a data mapping relationship between the thermal component node data container and the control body data container, write the current internal or external wall temperature obtained by solving the solid heat conduction equation stored in the thermal component node data container into the control body data container and use it as the input parameter required by the wall heat transfer source term function, and write the current internal or external wall heat flux density calculated by the wall heat transfer source term function stored in the control body data container into the thermal component node data container and use it as the thermal boundary input parameter required for the closed-loop solution of the solid heat conduction equation;

[0010] Step 6: Incorporate the solid heat conduction equation solution task of the thermal component node into the generalized source term function calculation process of the two-fluid six-equation system, which is located after the control body wall heat transfer source term function calculation task in the calculation process. Through the data mapping relationship between the thermal component node data container and the control body data container, establish the parameter transfer relationship between the solid heat conduction equation solution task of the thermal component node and the wall heat transfer source term function calculation task, and form a reconstructed generalized source term function calculation process, which includes the calculation of the control body fluid physical property parameters, the calculation of the pipe physical property and scalar parameters based on the control body variable parameters, the calculation of the control body vapor-liquid flow rate based on the pipe variable parameters, the calculation of the wall heat transfer source term function, the solution of the solid heat conduction equation of the thermal component node, the two-phase flow type judgment, the interphase heat transfer source term function calculation, the interphase and wall friction function calculation, the local resistance calculation, the flow dissipation term calculation, the critical flow calculation, and the vapor-liquid counterflow CCFL calculation;

[0011] Step 7: Incorporate the reconstructed generalized source term function calculation process into the single-step solution logic process of the two-fluid six-equation system, replacing the existing generalized source term function calculation process. The other parts of the two-fluid six-equation system solution logic process remain unchanged.

[0012] Step 8: Execute the single-step solution logic flow of the two-fluid six-equation system. According to the calculation task sequence and variable parameter transfer relationship of the generalized source function calculation process, execute each source function calculation task in sequence. Use multi-node unit parallel calculation to execute the same type of source function calculation tasks of the control body or takeover. Use multi-block parallel calculation to execute the solid heat conduction equation solution task of the thermal component node.

[0013] Step 9: The two-fluid six-equation system is advanced along the time step, and the time series changes of the variable parameters of each control body model, takeover model and thermal component node model of the thermal hydraulic system are stored in the corresponding data containers respectively.

[0014] The data container of the control body model and the takeover model in step 4 stores all the data information required by the two-fluid six-equation system in the basic node unit, including the node unit number, type, model component and position information, upstream and downstream information of the node unit, geometric structure parameters, characteristic curve parameters, initial state parameters, variable parameter time series change data, and generalized source term function information; the data container of the thermal component node model stores all the data information required for the closure of the solid heat conduction equation, including the thermal component node number, thermal component node physical property parameters, thermal component node structural parameters and radial node division, thermal component node variable parameter time series change, thermal component node inner thermal interface connection information, and thermal component node inner boundary. Type and parameters, thermal interface connection information on the outside of the thermal component node, type and parameters of the outer boundary of the thermal component node, heat source distribution within the thermal component node, the inside of the thermal component node refers to the solid boundary with a smaller value of the radial coordinate axis, and the outside of the thermal component node refers to the solid boundary with a larger value of the radial coordinate axis. The thermal interface connection information on the inside or outside of the thermal component node refers to whether the thermal interface on the inside or outside of the thermal component node is empty. If not empty, the control body number of the thermal interface connection is given. The type and parameters of the inner or outer boundary of the thermal component node include the first type of thermal boundary condition, i.e., the fixed wall temperature condition, the second type of thermal boundary condition, i.e., the fixed heat flux density condition, and the third type of thermal boundary condition, i.e., the fixed ambient temperature and heat transfer coefficient condition.

[0015] The single-step solution logic flow of the two-fluid six-equation system in step 7 refers to the logic flow of a single time step in the process of the two-fluid six-equation system advancing along time, which includes, in sequence, the time step check and correction based on the Courant limit, the calculation of the generalized source term function, the assembly and calculation of the coefficient matrix of the two-fluid six-equation, the assembly and calculation of the coefficient matrix of the global pressure equation, the solution of the global pressure matrix equation, the calculation of the vapor-liquid flow rate of the connecting pipe based on the control body pressure, the calculation of the control body scalar based on the vapor-liquid flow rate of the connecting pipe, and the quality error check.

[0016] The types of control body or takeover source term function calculation tasks in step 8 include calculation of control body fluid physical property parameters, calculation of takeover physical properties and scalar parameters based on control body variable parameters, calculation of control body vapor-liquid flow rate based on takeover variable parameters, wall heat transfer source term function calculation, two-phase flow type judgment, interphase heat transfer source term function calculation, interphase and wall friction function calculation, local resistance calculation, flow dissipation term calculation, critical flow calculation, and vapor-liquid reverse flow CCFL calculation.

[0017] The multi-node unit parallel computing method of the control body or takeover source item function calculation task in step 8 is: using multi-threaded parallel computing method to simultaneously execute multiple control bodies or takeover source item function calculation tasks, one thread executes one control body or takeover source item function calculation task.

[0018] The task of solving the solid heat conduction equation of the thermal component node in step 8 is: based on the data information such as the node physical properties parameters, node structure parameters, node radial node division, inner and outer boundary parameters, internal heat source distribution, and temperature distribution of each node of the node at the previous moment stored in the thermal component node data container, combined with the current time step of the two-fluid six-equation system, assemble the matrix equation corresponding to the solid heat conduction equation of the thermal component node, and use the LU decomposition method or iterative solution method to calculate the temperature distribution of each node of the thermal component node and the inner and outer wall temperatures at the current moment.

[0019] The multi-node parallel computing method for solving the solid heat conduction equation of the thermal component node in step 8 is: using a multi-threaded parallel computing method to simultaneously execute the solid heat conduction equation solving tasks of multiple thermal component nodes, with one thread executing one thermal component node solid heat conduction equation solving task.

[0020] A parallel computing device for the solid heat conduction equation of thermal components applicable to the Modelica specification comprises the following components: a thermal-hydraulic system topology generation module, a data container configuration module, a data container retrieval positioning and data mapping module, a generalized source term function calculation process and task scheduling module, a data container-based multi-node parallel solution module for the solid heat conduction equation, a data container-based multi-node unit parallel computing module for the thermal-hydraulic source term function, and a single-step solution module for the two-fluid six-equation system.

[0021] The thermal-hydraulic system topology structure generation module converts the thermal-hydraulic system model into a flattened system model consisting of a control body model, a takeover model, and a thermal component node model connected in an orderly manner, and numbers the control body model, the takeover model, and the thermal component node model respectively. The control body model and the takeover model are staggeredly connected through flow interfaces, and the thermal component node model is connected to the control body model through a thermal interface on one side. The thermal component node model corresponds one-to-one to the control body model.

[0022] The data container configuration module configures a data container for each control body model, takeover model and thermal component node model in the memory space, supporting direct reading and writing of control body, takeover or thermal component node data information in the data container, wherein: the data container of the control body model and the takeover model stores all the data information required for the two-fluid six-equation system in the basic node unit, including the node unit number, type, model component and location information, upstream and downstream information of the node unit, geometric structure parameters, characteristic curve parameters, initial state parameters, variable parameter time series change data, generalized source term function information, etc.; the data container of the thermal component node model stores all the data information required for the closure of the solid heat conduction equation, including the thermal component node number, thermal component node physical property parameters, thermal component node structural parameters and radial node division, thermal component node variable parameter time series change, thermal component node inner side thermal interface connection information, thermal component node inner side boundary type and parameters, thermal component node outer side thermal interface connection information, thermal component node outer side boundary type and parameters, and heat source distribution within the thermal component node.

[0023] The data container retrieval positioning and data mapping module retrieves and locates the data container of the control body model connected to the inner or outer thermal interface of the thermal component node according to the control body number of the inner or outer thermal interface connection information of the data container, establishes a data mapping relationship between the thermal component node data container and the control body data container, writes the inner or outer wall temperature at the current moment obtained by solving the solid heat conduction equation stored in the thermal component node data container into the control body data container and uses it as the input parameter required by the wall heat transfer source term function, and writes the inner or outer wall heat flux density at the current moment obtained by calculating the wall heat transfer source term function stored in the control body data container into the thermal component node data container and uses it as the thermal boundary input parameter required for the closed solution of the solid heat conduction equation.

[0024] The generalized source term function calculation process and task scheduling module incorporates the task of solving the solid heat conduction equation of the thermal component node into the generalized source term function calculation process of the two-fluid six-equation system, and is located after the control body wall heat transfer source term function calculation task in the calculation process, forming a reconstructed generalized source term function calculation process, which includes the calculation of the control body fluid physical property parameters, the calculation of the physical properties and scalar parameters of the connecting pipe based on the control body variable parameters, the calculation of the control body vapor-liquid flow rate based on the connecting pipe variable parameters, the calculation of the wall heat transfer source term function, the solution of the solid heat conduction equation of the thermal component node, the two-phase flow type judgment, the calculation of the interphase heat transfer source term function, the calculation of the interphase and wall friction function, the calculation of the local resistance, the calculation of the flow dissipation term, the critical flow calculation, the vapor-liquid reverse flow CCFL calculation, etc.

[0025] The data container-based multi-node parallel solution module for the solid heat conduction equation schedules and executes the solid heat conduction equation solution task of the thermal component node according to the reconstructed generalized source term function calculation process, and adopts a multi-threaded parallel computing method to simultaneously execute the solid heat conduction equation solution tasks of multiple thermal component nodes. One thread executes one solid heat conduction equation solution task of the thermal component node. The solid heat conduction equation solution task of a single thermal component node is as follows: based on the node physical properties, node structure parameters, node radial node division, inner and outer boundary parameters, internal heat source distribution, temperature distribution of each node of the node at the previous moment stored in the thermal component node data container, combined with the current time step of the two-fluid six-equation system, the matrix equation corresponding to the solid heat conduction equation of the thermal component node is assembled, and the temperature distribution of each node of the thermal component node and the inner and outer wall temperatures at the current moment are calculated using the LU decomposition method or the iterative solution method.

[0026] The specific process of solving the solid heat conduction equation of a single thermal component segment includes: the axial temperature gradient of the thermal component is much smaller than the radial temperature gradient, and the solid heat conduction equation of a single thermal component segment is:

[0027]

[0028] Where r is the distance in the normal direction of the wall, ρ is the solid density, C is the solid specific heat capacity, T is the temperature, λ is the thermal conductivity, and S is the internal heat source density;

[0029] A single thermal component node is divided into nodes evenly along the radial direction. The number of nodes is M, node 1 is the inner wall, node M is the outer wall, node m is the non-wall boundary node, δr is the distance between adjacent nodes, and the time step is Δt.

[0030] Discretize (1) in space and time. For non-wall boundary nodes m, it satisfies:

[0031]

[0032] Where: subscript m represents the discrete node number of the thermal component block, and the discrete node number increases by 1 in the radial positive direction; subscript Indicates the center section number between node m and node m+1; superscript n indicates the nth time moment, superscript n+1 indicates the n+1th time moment, V m 、s m From the number Center section to number The volume and average internal heat source density between the central sections;

[0033] Formula (2) can be simplified as follows:

[0034]

[0035] in:

[0036]

[0037] (1) Inner wall node 1

[0038] According to the thermal boundary type, it satisfies:

[0039]

[0040] 1) The first type of thermal boundary condition is a constant wall temperature T Win , at this time, there is no thermal interface on the inner wall, and the user configures the inner wall temperature T Win ,

[0041] a1=1,d 1，2 =0, b1=T Win ;

[0042] 2) The second type of thermal boundary condition is constant heat flux density q Win , including when there is a thermal interface on the inner wall, the control body model gives the inner wall heat flux density q to the thermal component node through the inner thermal interface Win and the user-configured inner wall heat flux q when there is no thermal interface on the inner wall Win situation,

[0043]

[0044] 3) The third type of thermal boundary condition is a constant ambient temperature T ein and heat transfer coefficient h ein , at this time, there is no thermal interface on the inner wall, and the user configures the ambient temperature T ein and heat transfer coefficient h ein ,

[0045]

[0046] (2) Outer wall node M

[0047] For the outer wall node M, according to the thermal boundary type, it satisfies:

[0048]

[0049] 1) The first type of thermal boundary condition is a constant wall temperature T Wout , at this time, there is no thermal interface on the outer wall, and the user configures the outer wall temperature T Wout ,

[0050] a M =1,d M，M-1 =0,b M =T Wout

[0051] 2) The second type of thermal boundary condition is constant heat flux density q Wout , including when there is a thermal interface on the outer wall, the control body model gives the outer wall heat flux density q to the thermal component node through the outer thermal interface Wout , and when there is no thermal interface on the outer wall, the user configures the outer wall heat flux density q Wout situation,

[0052]

[0053] 3) The third type of thermal boundary condition is a constant ambient temperature T eout and heat transfer coefficient h eout , at this time, there is no thermal interface on the outer wall, and the user configures the ambient temperature T eout and heat transfer coefficient h eout ,

[0054]

[0055]

[0056] Combining equations (3), (8) and (9), we can obtain the matrix equation:

[0057]

[0058] The LU decomposition method, Gaussian elimination method or iterative solution method can be used to solve Equation (10) and obtain the temperature distribution of each node of a single thermal component block at time n+1, that is:

[0059] The data container-based thermal hydraulic source term function multi-node unit parallel calculation module schedules the execution of source term function calculation tasks other than the task of solving the solid heat conduction equation of the thermal component node according to the reconstructed generalized source term function calculation process, and adopts a multi-threaded parallel calculation method to simultaneously execute the same type of source term function calculation tasks of multiple control bodies or takeovers. One thread executes the source term function calculation task of one control body or takeover. The types of source term function calculation tasks include calculation of control body fluid physical properties parameters, calculation of takeover physical properties and scalar parameters based on control body variable parameters, calculation of control body vapor-liquid flow rate based on takeover variable parameters, solution of solid heat conduction equation of the thermal component node, two-phase flow type judgment, calculation of interphase heat transfer source term function, calculation of interphase and wall friction function, local resistance calculation, flow dissipation term calculation, critical flow calculation, and vapor-liquid reverse flow CCFL calculation.

[0060] The single-step solution module of the two-fluid six-equation system substitutes the time step corrected based on the Courant limit check into the reconstructed generalized source term function calculation process in a single time step according to the single-step solution logic flow of the two-fluid six-equation system. Based on the calculation results of the generalized source term function, the coefficient matrix of the two-fluid six-equation is assembled and calculated. Then, the global pressure equation coefficient matrix assembly and calculation, global pressure matrix equation solution, pipe vapor-liquid flow rate calculation based on control body pressure, control body scalar calculation based on pipe vapor-liquid flow rate, quality error check and other tasks are carried out in sequence to obtain the variable parameters of each control body, pipe and thermal component node of the thermal-hydraulic system at the current moment and store them in the corresponding data container.

[0061] The beneficial effects of the present invention are:

[0062] (1) The present invention establishes a parallel computing device and method for solid heat conduction equations in a thermal hydraulic parallel solution framework applicable to the Modelica specification, which can effectively improve the computational efficiency of solving thermal hydraulic models coupled with thermal component models, such as reactor core models, pipeline models with thermal components, container models with thermal components, and heat exchanger models, thereby improving the computational efficiency of thermal hydraulic system models based on Modelica, and providing technical support for rapid design verification of thermal hydraulic systems and real-time simulation of digital twin models.

[0063] (2) The present invention provides a thermal boundary processing method for a thermal component model and a method for generating a solvable matrix equation. It can use a unified matrix equation form to construct a solid thermal conductivity matrix equation for thermal components of different structural forms, and supports three types of thermal boundaries: the first type of thermal boundary with a fixed wall temperature, the second type of thermal boundary with a fixed heat flux density, and the third type of thermal boundary with a fixed ambient temperature and a fixed heat transfer coefficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 Provides an example of flattening processing and data container configuration for a pipeline model with thermal components.

[0065] Figure 2 Provides an example of flattening the flow channel model component of a heat exchanger and configuring a data container.

[0066] Figure 3 A data association logic diagram of a thermal component node data container and a control volume data container based on the thermal interface connection information inside the thermal component node;

[0067] Figure 4 A data association logic diagram of a thermal component node data container and a control volume data container based on the thermal interface connection information outside the thermal component node;

[0068] Figure 5A data association logic diagram of a thermal component node data container and a control volume data container based on the thermal interface connection information of the thermal component node inside and outside;

[0069] Figure 6 It is a parallel computing device for solid heat conduction equations of thermal components that is applicable to Modelica standards.

[0070] Figure 7 Schematic diagram of discrete node partitioning for a single thermal component block. DETAILED DESCRIPTION

[0071] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0072] A parallel calculation method for the solid heat conduction equation of a thermal component applicable to the Modelica specification includes the following steps:

[0073] Step 1: In the Modelica-based thermal-hydraulic system model, traverse the thermal component model and establish the corresponding connection relationship between the thermal component model and the thermal-hydraulic model components through the thermal interface connection information of the thermal component model.

[0074] Step 2: According to the discrete node division method of the thermal component model and its corresponding thermal-hydraulic model components, the thermal component model and its corresponding thermal-hydraulic model components are flattened, and the thermal-hydraulic model components are converted into a model in which the control body model and the takeover model are interlaced and orderly connected. The thermal component model is also converted into a set of thermal component block models that correspond one-to-one to the thermal-hydraulic control body model.

[0075] For example, for a pipeline model with thermal components, based on the number of discrete nodes N defined in the pipeline model, the pipeline model is converted into a model consisting of N control body models and N-1 pipes and tubes connected in an interlaced and orderly manner. The thermal component model is converted into N thermal component block models, and each thermal component block model is connected to a corresponding control body model through a thermal interface. For a heat exchanger flow channel model, based on the number of discrete nodes N defined in the heat exchanger flow channel, the hot-side flow channel model and the cold-side flow channel model are respectively converted into N control body models and N-1 pipes and tubes connected in an interlaced and orderly manner. The thermal component model is converted into N thermal component block models, and each thermal component block model is connected to a hot-side control body model and a cold-side control body model through a thermal interface.

[0076] Step 3: Flatten the model components in the thermal-hydraulic system model that are not connected to the thermal components. Connect the flattened thermal-hydraulic model through the flow interface, and convert the thermal-hydraulic system model into a flattened system model that is orderly connected by the control body model, the pipe model, and the thermal component node model. The control body model and the pipe model are staggeredly connected through the flow interface, and the thermal component node model is connected to the control body model through the thermal interface on one side. The thermal component node model corresponds one-to-one with the control body model.

[0077] Step 4: Sequentially number the control body model, takeover model, and thermal component node model of the flattened system model, and configure a data container for each control body model, takeover model, and thermal component node model in the memory space to support direct reading and writing of control body, takeover, or thermal component node data information in the data container.

[0078] The data containers of the control body model and the takeover model store all the data and information required for the two-fluid six-equation system at the basic node unit, including the node unit number, type, model component and location information, upstream and downstream information of the node unit, geometric structure parameters, characteristic curve parameters, initial state parameters, variable parameter time-series change data, generalized source term function information, etc. The data container of the thermal component block model stores all the data and information required to close the solid heat conduction equation, including the thermal component block number, thermal component block physical properties, thermal component block structural parameters and radial node division, thermal component block variable parameter time-series change, thermal component block inner side thermal interface connection information, thermal component block inner side boundary type and parameters, thermal component block outer side thermal interface connection information, thermal component block outer side boundary type and parameters, heat source distribution within the thermal component block, etc. The thermal component block inner side refers to the solid boundary with smaller radial coordinate axis values, and the thermal component block outer side refers to the solid boundary with larger radial coordinate axis values. The thermal interface connection information for the inner or outer thermal interface of the thermal component segment indicates whether the thermal interface for the inner or outer thermal interface of the thermal component segment is empty. If it is not empty, the control body number of the thermal interface connection is given. The boundary types and parameters for the inner or outer thermal interface of the thermal component segment include the first type of thermal boundary conditions, i.e., fixed wall temperature conditions; the second type of thermal boundary conditions, i.e., fixed heat flux conditions; and the third type of thermal boundary conditions, i.e., fixed ambient temperature and heat transfer coefficient conditions.

[0079] Step 5: Traverse the thermal component node data container, and according to the control body number of the inner or outer thermal interface connection information of the data container, retrieve and locate the data container of the control body model connected to the inner or outer thermal interface of the thermal component node, establish a data mapping relationship between the thermal component node data container and the control body data container, write the inner or outer wall temperature at the current moment obtained by solving the solid heat conduction equation stored in the thermal component node data container into the control body data container and use it as the input parameter required by the wall heat transfer source term function, and write the inner or outer wall heat flux density at the current moment obtained by calculating the wall heat transfer source term function stored in the control body data container into the thermal component node data container and use it as the thermal boundary input parameter required for the closed solution of the solid heat conduction equation.

[0080] Step 6: Incorporate the solid heat conduction equation solution task of the thermal component node into the generalized source term function calculation process of the two-fluid six-equation system, which is located after the control body wall heat transfer source term function calculation task in the calculation process. Through the data mapping relationship between the thermal component node data container and the control body data container, establish the parameter transfer relationship between the solid heat conduction equation solution task of the thermal component node and the wall heat transfer source term function calculation task, and form a reconstructed generalized source term function calculation process, which includes the calculation of the control body fluid physical property parameters, the calculation of the pipe physical property and scalar parameters based on the control body variable parameters, the calculation of the control body vapor-liquid flow rate based on the pipe variable parameters, the wall heat transfer source term function calculation, the solution of the solid heat conduction equation of the thermal component node, the two-phase flow type judgment, the interphase heat transfer source term function calculation, the interphase and wall friction function calculation, the local resistance calculation, the flow dissipation term calculation, the critical flow calculation, the vapor-liquid reverse flow CCFL calculation, etc.

[0081] Step 7: Incorporate the reconstructed generalized source term function calculation process into the single-step solution logic process for the two-fluid six-equation system, replacing the existing generalized source term function calculation process. The other parts of the two-fluid six-equation system solution logic process remain unchanged. The single-step solution logic process for the two-fluid six-equation system refers to the logic process of a single time step during the time progression of the two-fluid six-equation system, which includes, in sequence, time step check and correction based on the Courant limit, generalized source term function calculation, assembly and calculation of the two-fluid six-equation coefficient matrix, assembly and calculation of the global pressure equation coefficient matrix, solution of the global pressure matrix equation, calculation of the pipe vapor-liquid flow rate based on the control volume pressure, calculation of the control volume scalar based on the pipe vapor-liquid flow rate, and quality error check.

[0082] Step 8: Execute the single-step solution logic process of the two-fluid six-equation system. According to the calculation task sequence and variable parameter transfer relationship of the generalized source function calculation process, execute each source function calculation task in sequence and in an orderly manner. Use multi-node unit parallel calculation to execute the same type of source function calculation tasks of the control body or takeover. Use multi-block parallel calculation to execute the solid heat conduction equation solution task of the thermal component node.

[0083] The types of control body or takeover source term function calculation tasks include calculation of control body fluid physical property parameters, calculation of takeover physical properties and scalar parameters based on control body variable parameters, calculation of control body vapor-liquid flow rate based on takeover variable parameters, wall heat transfer source term function calculation, two-phase flow pattern determination, interphase heat transfer source term function calculation, interphase and wall friction function calculation, local resistance calculation, flow dissipation term calculation, critical flow calculation, vapor-liquid counterflow CCFL calculation, etc. The multi-node unit parallel calculation method of the control body or takeover source term function calculation task is: using multi-threaded parallel computing to simultaneously execute multiple control body or takeover source term function calculation tasks, with one thread executing one control body or takeover source term function calculation task.

[0084] The task of solving the solid heat conduction equation for the thermal component node is to assemble the matrix equation corresponding to the solid heat conduction equation for the thermal component node based on the data information stored in the thermal component node data container, including the node physical properties, node structural parameters, node radial node division, inner and outer boundary parameters, internal heat source distribution, and the temperature distribution of each node in the node at the previous moment, combined with the current time step of the two-fluid six-equation system. The temperature distribution of each node in the thermal component node at the current moment, as well as the inner and outer wall temperatures, are calculated using the LU decomposition method or iterative solution method. The multi-node parallel computing method for solving the solid heat conduction equation for the thermal component node is to simultaneously execute the solid heat conduction equation solving tasks for multiple thermal component nodes using a multi-threaded parallel computing method, with one thread executing each solid heat conduction equation solving task for the thermal component node.

[0085] Step 9: The two-fluid six-equation system is advanced along the time step, and the time series changes of the variable parameters of each control body model, takeover model and thermal component node model of the thermal hydraulic system are stored in the corresponding data containers respectively.

[0086] A parallel computing device for the solid heat conduction equation of thermal components applicable to the Modelica specification comprises the following components: a thermal-hydraulic system topology generation module, a data container configuration module, a data container retrieval positioning and data mapping module, a generalized source term function calculation process and task scheduling module, a data container-based multi-node parallel solution module for the solid heat conduction equation, a data container-based multi-node unit parallel computing module for the thermal-hydraulic source term function, and a single-step solution module for the two-fluid six-equation system.

[0087] The thermal-hydraulic system topology structure generation module converts the thermal-hydraulic system model into a flattened system model consisting of a control body model, a takeover model, and a thermal component node model connected in order, and numbers the control body model, the takeover model, and the thermal component node model respectively. The control body model and the takeover model are interlaced through flow interfaces, and the thermal component node model is connected to the control body model through a thermal interface on one side. The thermal component node model corresponds one-to-one to the control body model.

[0088] The data container configuration module configures data containers for each control body model, takeover model, and thermal component node model in the memory space, supporting direct reading and writing of control body, takeover, or thermal component node data information in the data containers. Specifically, the data containers of the control body model and takeover model store all the data information required for the two-fluid six-equation system at the basic node unit, including the node unit number, type, model component and location information, upstream and downstream information of the node unit, geometric structure parameters, characteristic curve parameters, initial state parameters, variable parameter time series change data, generalized source function information, etc. The data container of the thermal component node model stores all the data information required for closing the solid heat conduction equation, including the thermal component node number, thermal component node physical properties, thermal component node structural parameters and radial node division, thermal component node variable parameter time series change, thermal component node internal thermal interface connection information, thermal component node internal boundary type and parameters, thermal component node external thermal interface connection information, thermal component node external boundary type and parameters, and heat source distribution within the thermal component node.

[0089] The data container retrieval positioning and data mapping module retrieves and locates the data container of the control body model connected to the inner or outer thermal interface of the thermal component node according to the control body number of the inner or outer thermal interface connection information of the data container, establishes a data mapping relationship between the thermal component node data container and the control body data container, writes the inner or outer wall temperature at the current moment obtained by solving the solid heat conduction equation stored in the thermal component node data container into the control body data container and uses it as the input parameter required by the wall heat transfer source term function, and writes the inner or outer wall heat flux density at the current moment obtained by calculating the wall heat transfer source term function stored in the control body data container into the thermal component node data container and uses it as the thermal boundary input parameter required for the closed solution of the solid heat conduction equation.

[0090] The general source term function calculation process and task scheduling module incorporates the task of solving the solid heat conduction equation for the hot component node into the general source term function calculation process of the two-fluid six-equation system. It is located after the task of calculating the heat transfer source term function on the control volume wall surface in the calculation process, forming a reconstructed general source term function calculation process, which successively includes the calculation of control volume fluid physical properties, the calculation of nozzle physical properties and scalar parameters based on control volume variable parameters, the calculation of control volume vapor-liquid flow velocities based on nozzle variable parameters, the calculation of heat transfer source term function on the wall surface, the solution of the solid heat conduction equation for the hot component node, the judgment of two-phase flow patterns, the calculation of interphase heat transfer source term function, the calculation of interphase and wall friction functions, the calculation of local resistance, the calculation of flow dissipation terms, the calculation of critical flow, the calculation of countercurrent vapor-liquid flow CCFL, etc.

[0091] The multi-block parallel solution module of the solid heat conduction equation based on data containers schedules and executes the task of solving the solid heat conduction equation for the hot component node according to the reconstructed general source term function calculation process. It uses a multi-thread parallel computing method to simultaneously execute the tasks of solving the solid heat conduction equations for multiple hot component nodes, with one thread executing the task of solving the solid heat conduction equation for one hot component node. The task of solving the solid heat conduction equation for a single hot component node is as follows: According to the data information such as the node physical properties, node structure parameters, radial node division of the node, inner and outer boundary parameters, internal heat source distribution, and temperature distribution of each node in the previous time step stored in the data container of the hot component node, combined with the current time step of the two-fluid six-equation system, assemble the matrix equation corresponding to the solid heat conduction equation of the hot component node, and use the LU decomposition method or iterative solution method to calculate the temperature distribution of each node in the hot component node and the inner and outer wall surface temperatures at the current moment.

[0092] Among them, the specific process of solving the solid heat conduction equation for a single hot component node includes:

[0093] Generally, the axial temperature gradient of the hot component is much smaller than the radial temperature gradient. The heat transfer of the hot component can only occur in the radial direction, and the heat transfer between each node of the hot component can be ignored. Therefore, the solid heat conduction equation for a single hot component node is:

[0094]

[0095] Among them, r is the distance in the wall normal direction, ρ is the solid density, C is the solid specific heat capacity, T is the temperature, λ is the thermal conductivity, and S is the internal heat source density.

[0096] The nodes of a single hot component node are evenly divided in the radial direction, the number of nodes is M, node 1 is the inner wall surface, node M is the outer wall surface, node m (1 < m < M) is a non-wall boundary node, δr is the distance between adjacent nodes, and the time step is Δt.

[0097] Discretize equation (1) in space and time. For the non-wall boundary node m, it satisfies:

[0098]

[0099] Where: subscript m represents the discrete node number of the thermal component block, and the discrete node number increases by 1 in the radial positive direction; subscript Indicates the center section number between node m and node m+1; superscript n indicates the nth time moment, superscript n+1 indicates the n+1th time moment, V m 、s m From the number Center section to number The volume between the central cross section and the average internal heat source density.

[0100] Formula (2) can be simplified as follows:

[0101]

[0102] in:

[0103]

[0104] (1) Inner wall node 1

[0105] According to the thermal boundary type, it satisfies:

[0106]

[0107] 1) The first type of thermal boundary condition is a constant wall temperature T Win , at this time, there is no thermal interface on the inner wall, and the user configures the inner wall temperature T Win ,

[0108] a1=1,d 1，2 =0, b1=T Win ;

[0109] 2) The second type of thermal boundary condition is constant heat flux density q Win , including when there is a thermal interface on the inner wall, the control body model gives the inner wall heat flux density q to the thermal component node through the inner thermal interface Win and the user-configured inner wall heat flux q when there is no thermal interface on the inner wall Win situation,

[0110]

[0111] 3) The third type of thermal boundary condition is a constant ambient temperature T ein and heat transfer coefficient h ein , at this time, there is no thermal interface on the inner wall, and the user configures the ambient temperature T ein and heat transfer coefficient h ein ,

[0112]

[0113] (2) Outer wall node M

[0114] For the outer wall node M, according to the thermal boundary type, it satisfies:

[0115]

[0116] 1) The first type of thermal boundary condition is a constant wall temperature T Wout , at this time, there is no thermal interface on the outer wall, and the user configures the outer wall temperature T Wout ,

[0117] a M =1,d M，M-1 =0,b M =T Wout

[0118] 2) The second type of thermal boundary condition is constant heat flux density q Wout , including when there is a thermal interface on the outer wall, the control body model gives the outer wall heat flux density q to the thermal component node through the outer thermal interface Wout , and when there is no thermal interface on the outer wall, the user configures the outer wall heat flux density q Wout situation,

[0119]

[0120] 3) The third type of thermal boundary condition is a constant ambient temperature T eout and heat transfer coefficient h eout , at this time, there is no thermal interface on the outer wall, and the user configures the ambient temperature T eout and heat transfer coefficient h eout ,

[0121]

[0122] Combining equations (3), (8) and (9), we can obtain the matrix equation:

[0123]

[0124] The LU decomposition method, Gaussian elimination method or iterative solution method can be used to solve Equation (10) and obtain the temperature distribution of each node of a single thermal component block at time n+1, that is:

[0125] The multi-node unit parallel calculation module of the thermal hydraulic source term function based on the data container schedules the execution of source term function calculation tasks other than the solution task of the solid heat conduction equation of the thermal component node according to the reconstructed generalized source term function calculation process. The multi-threaded parallel calculation method is used to simultaneously execute the same type of source term function calculation tasks of multiple control bodies or takeovers. One thread executes the source term function calculation task of one control body or takeover. The types of source term function calculation tasks include the calculation of the control body fluid physical properties parameters, the calculation of the takeover physical properties and scalar parameters based on the control body variable parameters, the calculation of the control body vapor-liquid flow rate based on the takeover variable parameters, the solution of the solid heat conduction equation of the thermal component node, the judgment of the two-phase flow type, the calculation of the interphase heat transfer source term function, the calculation of the interphase and wall friction function, the calculation of the local resistance, the calculation of the flow dissipation term, the critical flow calculation, the vapor-liquid reverse flow CCFL calculation and other tasks.

[0126] The single-step solution module of the two-fluid six-equation system, in a single time step, follows the single-step solution logic flow of the two-fluid six-equation system, substitutes the time step corrected based on the Courant limit check into the reconstructed generalized source term function calculation process, assembles and calculates the coefficient matrix of the two-fluid six-equation based on the calculation results of the generalized source term function, and then carries out the tasks of assembling and calculating the coefficient matrix of the global pressure equation, solving the global pressure matrix equation, calculating the vapor-liquid flow rate of the pipe based on the control body pressure, calculating the control body scalar based on the vapor-liquid flow rate of the pipe, and checking the quality error in sequence, to obtain the variable parameters of each control body, pipe and thermal component node of the thermal-hydraulic system at the current moment, and store them in the corresponding data container.

Claims

1. A parallel calculation method for the solid heat conduction equation of thermal components applicable to Modelica specification, characterized by: The steps include: Step 1: In the Modelica-based thermal-hydraulic system model, traverse the thermal component model and establish the corresponding connection relationship between the thermal component model and the thermal-hydraulic model components through the thermal interface connection information of the thermal component model; Step 2: Flatten the thermal component model and its corresponding thermal-hydraulic model components according to their discrete node partitioning method. Convert the thermal-hydraulic model components into a model consisting of an interlaced and orderly connection of control body models and nozzle models. Furthermore, convert the thermal component model into a collection of thermal component node models that correspond one-to-one to the thermal-hydraulic control body models. Step 3: Flatten the model components in the thermal-hydraulic system model that are not connected to the thermal components. Connect the flattened thermal-hydraulic model through flow interfaces, and convert the thermal-hydraulic system model into a flattened system model that is sequentially connected by the control body model, the pipe model, and the thermal component node model. The control body model and the pipe model are staggeredly connected through flow interfaces, and the thermal component node model is connected to the control body model through a thermal interface on one side. The thermal component node model corresponds one-to-one with the control body model. Step 4: Sequentially number the control body model, takeover model, and thermal component node model of the flattened system model, and configure a data container for each control body model, takeover model, and thermal component node model in the memory space; Step 5: Traverse the thermal component node data container, and according to the control body number of the internal or external thermal interface connection information of the data container, retrieve and locate the data container of the control body model connected to the internal or external thermal interface of the thermal component node, establish a data mapping relationship between the thermal component node data container and the control body data container, write the current internal or external wall temperature obtained by solving the solid heat conduction equation stored in the thermal component node data container into the control body data container and use it as the input parameter required by the wall heat transfer source term function, and write the current internal or external wall heat flux density calculated by the wall heat transfer source term function stored in the control body data container into the thermal component node data container and use it as the thermal boundary input parameter required for the closed-loop solution of the solid heat conduction equation; Step 6: Incorporate the solid heat conduction equation solution task of the thermal component node into the generalized source term function calculation process of the two-fluid six-equation system, which is located after the control body wall heat transfer source term function calculation task in the calculation process. Through the data mapping relationship between the thermal component node data container and the control body data container, establish the parameter transfer relationship between the solid heat conduction equation solution task of the thermal component node and the wall heat transfer source term function calculation task, and form a reconstructed generalized source term function calculation process, which includes the calculation of the control body fluid physical property parameters, the calculation of the pipe physical property and scalar parameters based on the control body variable parameters, the calculation of the control body vapor-liquid flow rate based on the pipe variable parameters, the calculation of the wall heat transfer source term function, the solution of the solid heat conduction equation of the thermal component node, the two-phase flow type judgment, the interphase heat transfer source term function calculation, the interphase and wall friction function calculation, the local resistance calculation, the flow dissipation term calculation, the critical flow calculation, and the vapor-liquid counterflow CCFL calculation; Step 7: Incorporate the reconstructed generalized source term function calculation process into the single-step solution logic process of the two-fluid six-equation system, replacing the existing generalized source term function calculation process. The other parts of the two-fluid six-equation system solution logic process remain unchanged. Step 8: Execute the single-step solution logic flow of the two-fluid six-equation system. According to the calculation task sequence and variable parameter transfer relationship of the generalized source function calculation process, execute each source function calculation task in sequence. Use multi-node unit parallel calculation to execute the same type of source function calculation tasks of the control body or takeover. Use multi-block parallel calculation to execute the solid heat conduction equation solution task of the thermal component node. Step 9: The two-fluid six-equation system is advanced along the time step, and the time series changes of the variable parameters of each control body model, takeover model and thermal component node model of the thermal hydraulic system are stored in the corresponding data containers respectively.

2. The parallel calculation method for the solid heat conduction equation of a thermal component applicable to the Modelica specification according to claim 1, characterized in that: The data containers of the control body model and the takeover model in step 4 store all the data information required by the two-fluid six-equation system at the basic node unit, including the node unit number, type, model component and location information, upstream and downstream information of the node unit, geometric structure parameters, characteristic curve parameters, initial state parameters, variable parameter time series change data, and generalized source function information; The data container of the thermal component node model stores all data information required for closing the solid heat conduction equation, including the thermal component node number, thermal component node physical properties, thermal component node structural parameters and radial node division, time series changes of thermal component node variable parameters, thermal component node inner thermal interface connection information, thermal component node inner boundary type and parameters, thermal component node outer thermal interface connection information, thermal component node outer boundary type and parameters, and heat source distribution within the thermal component node. The inner side of the thermal component node refers to the solid boundary with a smaller radial coordinate axis value, and the outer side of the thermal component node refers to the solid boundary with a larger radial coordinate axis value. The thermal interface connection information of the inner or outer side of the thermal component node refers to whether the thermal interface of the inner or outer side of the thermal component node is empty. If not empty, the control body number of the thermal interface connection is given. The boundary type and parameters of the inner or outer side of the thermal component node include the first type of thermal boundary condition, i.e., the fixed wall temperature condition, the second type of thermal boundary condition, i.e., the fixed heat flux density condition, and the third type of thermal boundary condition, i.e., the fixed ambient temperature and heat transfer coefficient condition.

3. The parallel calculation method for the solid heat conduction equation of a thermal component applicable to the Modelica specification according to claim 1, characterized in that: The single-step solution logic flow of the two-fluid six-equation system in step 7 refers to the logic flow of a single time step in the process of the two-fluid six-equation system advancing along time, which includes, in sequence, the time step check and correction based on the Courant limit, the calculation of the generalized source term function, the assembly and calculation of the coefficient matrix of the two-fluid six-equation, the assembly and calculation of the coefficient matrix of the global pressure equation, the solution of the global pressure matrix equation, the calculation of the vapor-liquid flow rate of the connecting pipe based on the control body pressure, the calculation of the control body scalar based on the vapor-liquid flow rate of the connecting pipe, and the quality error check.

4. The parallel calculation method for the solid heat conduction equation of a thermal component applicable to the Modelica specification according to claim 1, characterized in that: The types of control body or takeover source term function calculation tasks in step 8 include calculation of control body fluid physical property parameters, calculation of takeover physical properties and scalar parameters based on control body variable parameters, calculation of control body vapor-liquid flow rate based on takeover variable parameters, wall heat transfer source term function calculation, two-phase flow type judgment, interphase heat transfer source term function calculation, interphase and wall friction function calculation, local resistance calculation, flow dissipation term calculation, critical flow calculation, and vapor-liquid reverse flow CCFL calculation.

5. The parallel calculation method for the solid heat conduction equation of a thermal component applicable to the Modelica specification according to claim 1, characterized in that: The multi-node unit parallel computing method of the control body or takeover source item function calculation task in step 8 is: using multi-threaded parallel computing method to simultaneously execute multiple control bodies or takeover source item function calculation tasks, one thread executes one control body or takeover source item function calculation task.

6. The parallel calculation method for the solid heat conduction equation of a thermal component applicable to the Modelica specification according to claim 1, characterized in that: The task of solving the solid heat conduction equation of the thermal component node in step 8 is: based on the data information such as the node physical properties parameters, node structure parameters, node radial node division, inner and outer boundary parameters, internal heat source distribution, and temperature distribution of each node of the node at the previous moment stored in the thermal component node data container, combined with the current time step of the two-fluid six-equation system, assemble the matrix equation corresponding to the solid heat conduction equation of the thermal component node, and use the LU decomposition method or iterative solution method to calculate the temperature distribution of each node of the thermal component node and the inner and outer wall temperatures at the current moment.

7. The parallel calculation method for the solid heat conduction equation of a thermal component applicable to the Modelica specification according to claim 1, characterized in that: The multi-node parallel computing method for solving the solid heat conduction equation of the thermal component node in step 8 is: using a multi-threaded parallel computing method to simultaneously execute the solid heat conduction equation solving tasks of multiple thermal component nodes, with one thread executing one thermal component node solid heat conduction equation solving task.

8. A parallel computing device for solid heat conduction equations of thermal components applicable to Modelica specifications, characterized in that: It includes the following components: thermal-hydraulic system topology structure generation module, data container configuration module, data container retrieval positioning and data mapping module, generalized source term function calculation process and task scheduling module, multi-node block parallel solution module of solid heat conduction equation based on data container, multi-node unit parallel calculation module of thermal-hydraulic source term function based on data container, and single-step solution module of two-fluid six-equation system.

9. The parallel computing device for solid heat conduction equations of thermal components according to the Modelica standard as claimed in claim 8, characterized in that: The thermal-hydraulic system topology structure generation module converts the thermal-hydraulic system model into a flattened system model consisting of a control body model, a takeover model, and a thermal component node model connected in an orderly manner, and numbers the control body model, the takeover model, and the thermal component node model respectively. The control body model and the takeover model are staggeredly connected through flow interfaces, and the thermal component node model is connected to the control body model through a thermal interface on one side. The thermal component node model corresponds one-to-one to the control body model.

10. The parallel computing device for solid heat conduction equations of thermal components according to the Modelica standard as claimed in claim 8, characterized in that: The data container configuration module configures a data container for each control body model, takeover model and thermal component node model in the memory space, supporting direct reading and writing of control body, takeover or thermal component node data information in the data container, wherein: the data container of the control body model and the takeover model stores all the data information required for the two-fluid six-equation system in the basic node unit, including the node unit number, type, model component and location information, upstream and downstream information of the node unit, geometric structure parameters, characteristic curve parameters, initial state parameters, variable parameter time series change data, generalized source term function information, etc.; the data container of the thermal component node model stores all the data information required for the closure of the solid heat conduction equation, including the thermal component node number, thermal component node physical property parameters, thermal component node structural parameters and radial node division, thermal component node variable parameter time series change, thermal component node inner side thermal interface connection information, thermal component node inner side boundary type and parameters, thermal component node outer side thermal interface connection information, thermal component node outer side boundary type and parameters, and heat source distribution within the thermal component node.

11. The parallel computing device for solid heat conduction equations of thermal components according to the Modelica standard as claimed in claim 8, characterized in that: The data container retrieval positioning and data mapping module retrieves and locates the data container of the control body model connected to the inner or outer thermal interface of the thermal component node according to the control body number of the inner or outer thermal interface connection information of the data container, establishes a data mapping relationship between the thermal component node data container and the control body data container, writes the inner or outer wall temperature at the current moment obtained by solving the solid heat conduction equation stored in the thermal component node data container into the control body data container and uses it as the input parameter required by the wall heat transfer source term function, and writes the inner or outer wall heat flux density at the current moment obtained by calculating the wall heat transfer source term function stored in the control body data container into the thermal component node data container and uses it as the thermal boundary input parameter required for the closed solution of the solid heat conduction equation.

12. The parallel computing device for solid heat conduction equations of thermal components according to the Modelica standard as claimed in claim 8, characterized in that: The generalized source term function calculation process and task scheduling module incorporates the task of solving the solid heat conduction equation of the thermal component node into the generalized source term function calculation process of the two-fluid six-equation system, and is located after the control body wall heat transfer source term function calculation task in the calculation process, forming a reconstructed generalized source term function calculation process, which includes the calculation of the control body fluid physical property parameters, the calculation of the physical properties and scalar parameters of the connecting pipe based on the control body variable parameters, the calculation of the control body vapor-liquid flow rate based on the connecting pipe variable parameters, the calculation of the wall heat transfer source term function, the solution of the solid heat conduction equation of the thermal component node, the two-phase flow type judgment, the calculation of the interphase heat transfer source term function, the calculation of the interphase and wall friction function, the calculation of the local resistance, the calculation of the flow dissipation term, the critical flow calculation, the vapor-liquid reverse flow CCFL calculation, etc.

13. The parallel computing device for solid heat conduction equations of thermal components according to the Modelica standard as claimed in claim 8, characterized in that: The data container-based multi-node parallel solution module for the solid heat conduction equation schedules and executes the solid heat conduction equation solution task of the thermal component node according to the reconstructed generalized source term function calculation process, and adopts a multi-threaded parallel computing method to simultaneously execute the solid heat conduction equation solution tasks of multiple thermal component nodes. One thread executes one solid heat conduction equation solution task of the thermal component node. The solid heat conduction equation solution task of a single thermal component node is as follows: based on the node physical properties, node structure parameters, node radial node division, inner and outer boundary parameters, internal heat source distribution, temperature distribution of each node of the node at the previous moment stored in the thermal component node data container, combined with the current time step of the two-fluid six-equation system, the matrix equation corresponding to the solid heat conduction equation of the thermal component node is assembled, and the temperature distribution of each node of the thermal component node and the inner and outer wall temperatures at the current moment are calculated using the LU decomposition method or the iterative solution method.

14. The parallel computing device for solid heat conduction equations of thermal components according to claim 13, wherein: The specific process of solving the solid heat conduction equation of a single thermal component segment includes: the axial temperature gradient of the thermal component is much smaller than the radial temperature gradient, and the solid heat conduction equation of a single thermal component segment is: Where r is the distance in the normal direction of the wall, ρ is the solid density, C is the solid specific heat capacity, T is the temperature, λ is the thermal conductivity, and S is the internal heat source density; A single thermal component node is divided into nodes evenly along the radial direction. The number of nodes is M, node 1 is the inner wall, node M is the outer wall, node m is the non-wall boundary node, δr is the distance between adjacent nodes, and the time step is Δt. Discretize (1) in space and time. For non-wall boundary nodes m, it satisfies: Where: subscript m represents the discrete node number of the thermal component block, and the discrete node number increases by 1 in the radial positive direction; subscript Indicates the center section number between node m and node m+1; superscript n indicates the nth time moment, superscript n+1 indicates the n+1th time moment, V m 、s m From the number Center section to number The volume and average internal heat source density between the central sections; Formula (2) can be simplified as follows: in: (1) Inner wall node 1 According to the thermal boundary type, it satisfies: 1) The first type of thermal boundary condition is a constant wall temperature T Win , at this time, there is no thermal interface on the inner wall, and the user configures the inner wall temperature T Win , a1=1,d 1，2 =0, b1=T Win ; 2) The second type of thermal boundary condition is constant heat flux density q Win , including when there is a thermal interface on the inner wall, the control body model gives the inner wall heat flux density q to the thermal component node through the inner thermal interface Win and the user-configured inner wall heat flux q when there is no thermal interface on the inner wall Win situation, 3) The third type of thermal boundary condition is a constant ambient temperature T ein and heat transfer coefficient h ein , at this time, there is no thermal interface on the inner wall, and the user configures the ambient temperature T ein and heat transfer coefficient h ein , (2) Outer wall node M For the outer wall node M, according to the thermal boundary type, it satisfies: 1) The first type of thermal boundary condition is a constant wall temperature T Wout , at this time, there is no thermal interface on the outer wall, and the user configures the outer wall temperature T Wout , a M =1,d M，M-1 =0,b M =T Wout 2) The second type of thermal boundary condition is constant heat flux density q Wout , including when there is a thermal interface on the outer wall, the control body model gives the outer wall heat flux density q to the thermal component node through the outer thermal interface Wout , and when there is no thermal interface on the outer wall, the user configures the outer wall heat flux density q Wout situation, 3) The third type of thermal boundary condition is a constant ambient temperature T eout and heat transfer coefficient h eout , at this time, there is no thermal interface on the outer wall, and the user configures the ambient temperature T eout and heat transfer coefficient h eout , Combining equations (3), (8) and (9), we can obtain the matrix equation: The LU decomposition method, Gaussian elimination method or iterative solution method can be used to solve Equation (10) and obtain the temperature distribution of each node of a single thermal component block at time n+1, that is:

15. The parallel computing device for solid heat conduction equations of thermal components according to the Modelica standard as claimed in claim 8, characterized in that: The data container-based thermal hydraulic source term function multi-node unit parallel calculation module schedules the execution of source term function calculation tasks other than the task of solving the solid heat conduction equation of the thermal component node according to the reconstructed generalized source term function calculation process, and adopts a multi-threaded parallel calculation method to simultaneously execute the same type of source term function calculation tasks of multiple control bodies or takeovers. One thread executes the source term function calculation task of one control body or takeover. The types of source term function calculation tasks include calculation of control body fluid physical properties parameters, calculation of takeover physical properties and scalar parameters based on control body variable parameters, calculation of control body vapor-liquid flow rate based on takeover variable parameters, solution of solid heat conduction equation of the thermal component node, two-phase flow type judgment, calculation of interphase heat transfer source term function, calculation of interphase and wall friction function, local resistance calculation, flow dissipation term calculation, critical flow calculation, and vapor-liquid reverse flow CCFL calculation.

16. The parallel computing device for solid heat conduction equations of thermal components according to the Modelica standard as claimed in claim 8, characterized in that: The single-step solution module of the two-fluid six-equation system substitutes the time step corrected based on the Courant limit check into the reconstructed generalized source term function calculation process in a single time step according to the single-step solution logic flow of the two-fluid six-equation system. Based on the calculation results of the generalized source term function, the coefficient matrix of the two-fluid six-equation is assembled and calculated. Then, the global pressure equation coefficient matrix assembly and calculation, global pressure matrix equation solution, pipe vapor-liquid flow rate calculation based on control body pressure, control body scalar calculation based on pipe vapor-liquid flow rate, quality error check and other tasks are carried out in sequence to obtain the variable parameters of each control body, pipe and thermal component node of the thermal-hydraulic system at the current moment and store them in the corresponding data container.

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