Virtual Simulation System and Method for Full-Process Closed-Loop Structural Thermal Testing

Abstract

This invention provides a closed-loop virtual simulation system and method for structural thermal testing, comprising: performing heat transfer analysis and calculation for the virtual test using finite element analysis; applying thermal load to the virtual test using heating elements as basic units; implementing closed-loop control for the virtual test; visualizing the virtual test; classifying and managing the three-dimensional numerical models of the structural thermal test virtual simulation, including a digital material library and various digital models; modeling various test models for the structural thermal test, establishing a digital model of the test object, meshing the digital model, and assigning material properties from the digital material library to it, thus establishing a complete digital model library; and refining the established models. The structural thermal test virtual simulation system of this invention has predictive and guiding functions for structural thermal testing. Virtual testing and simulation verification have become major ways to shorten development cycles, reduce project risks, and lower development costs.

Description

Technical Field

[0001] This invention relates to the field of aerospace structural thermal test simulation technology, specifically to a closed-loop structural thermal test virtual simulation system and method. Background Technology

[0002] In the aerospace field, the demand for structural thermal testing of new models is increasing. However, structural thermal testing is costly, risky, and current methods have inherent limitations and difficulties. This necessitates higher technical capabilities in thermal testing to match the development of new models. In recent years, due to the rapid development of CAE technology, virtual testing technology has become a new means of verifying product thermal control designs.

[0003] The structural thermal testing virtual simulation system is specifically developed for structural thermal testing in the aerospace field. It is a simulation testing system that virtualizes the entire structural thermal testing process. The system can virtualize structural thermal testing and simulate and predict the test process and results.

[0004] Patent document CN114139420A (application number: CN202111462383.0) discloses a virtual testing method for quartz lamp radiant heating, belonging to the field of virtual testing technology, which solves the problem that existing virtual heating tests cannot accurately reflect the real heating situation. A virtual testing method for quartz lamp radiant heating includes the following steps: Step 1: Establishing a simulation model of the heating control system; Step 2: Establishing a simulation model for calculating the heating of the test piece; Step 3: Establishing real-time data exchange between Matlab and Abaqus; Step 4: Conducting a thermal environment test on the test piece. However, this patent cannot predict or guide structural thermal tests, and therefore cannot meet the needs of this invention. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a closed-loop virtual simulation system and method for structural thermal testing.

[0006] The structural thermal testing virtual simulation system with a closed-loop process provided by the present invention includes:

[0007] Thermal test calculation module: Uses finite element analysis to perform heat transfer analysis and calculation for virtual tests;

[0008] Virtual thermal test loading module: Uses heating elements as the basic unit to perform virtual thermal load loading tests;

[0009] Virtual thermal test control module: performs closed-loop control of the virtual test;

[0010] System visualization module: Provides a visual representation of the virtual experiment;

[0011] Digital Model Library: This library categorizes and manages three-dimensional numerical models for virtual simulation of structural thermal tests, including a digital material library and various digital models.

[0012] 3D modeling module: Models various test models for structural thermal tests, establishes digital models of test objects, meshes the digital models and assigns them material properties from the digital material library, and establishes a complete digital model library;

[0013] Model correction module: Corrects the established model.

[0014] Preferably, the thermal test calculation module includes: analyzing the ground radiative thermal environment using the Monte Carlo ray tracing algorithm, simulating the comprehensive impact of the ground environment on the model component using the computational fluid dynamics (CFD) method, and analyzing the steady-state or transient thermal response of the test component and test fixture using the computational heat transfer (CHT) method.

[0015] Preferably, the virtual thermal test loading module includes: calculating the thermoelectric conversion characteristics of the heating element quartz lamp using the resistivity method, obtaining the real-time operating voltage parameters of the quartz lamp, calculating the working temperature of the filament using the resistivity method, and thus realizing the application of radiative heat load to the heating element.

[0016] Preferably, the virtual thermal test loading module includes: modeling a quartz lamp as a heating element, considering the influence of the spiral tungsten filament on the heating power and the reflection and transmission of the radiant energy generated by the tungsten filament by the quartz glass tube wall, to form a digital model of the heating element; and building heat source models for various test scenarios according to different arrangement methods of the physical test quartz lamps based on the digital model of the heating element.

[0017] Preferably, the virtual thermal test control module includes: a PID control simulation method for obtaining the virtual thermal test using PID control simulation technology, and closed-loop control of the virtual test, wherein the PID controller is a discrete position controller.

[0018] Preferably, the system visualization module includes: previewing models in the digital model library, previewing virtual test scenarios, displaying virtual test control in real time, and displaying virtual test results.

[0019] Preferably, the process of calculating the thermal load of the quartz lamp heating element specifically includes: obtaining the real-time operating voltage of the heating element based on the correspondence between the control output of the physical test control system and the operating voltage of the heating element; then calculating the resistivity of the tungsten filament of the heating element under the real-time operating voltage; performing temperature interpolation calculation based on the correspondence between resistivity and temperature in the resistivity property table of tungsten metal at different temperatures; and obtaining the filament operating temperature under the real-time operating voltage. The operating temperature of the heating element filament is the thermal load.

[0020] Preferably, the formula for calculating the resistivity of the tungsten wire under the real-time operating voltage of the heating element is as follows:

[0021]

[0022] Where ρ is the resistivity of the tungsten wire, s is the cross-sectional area of ​​the tungsten wire, L is the total length of the tungsten wire, t is an empirical parameter, P_rated is the rated power of the lamp, and U_rated is the rated operating voltage of the lamp.

[0023] According to the closed-loop structural thermal test virtual simulation method provided by the present invention, the following steps are performed:

[0024] Step 1: Construct a digital material library based on the common material properties in structural thermal tests, classify the test objects according to their characteristics, optimize the models of key areas, establish digital models of the test objects, mesh them, and construct a digital model library.

[0025] Step 2: Based on the thermoelectric characteristics, radiation characteristics, working time constant, and working temperature parameters of the quartz lamp, establish a digital model with a single quartz lamp as the heating element, build a heater model based on the heating element, and establish a virtual thermal test loading module.

[0026] Step 3: Taking into account the effects of each experimental device and the surrounding environment, a thermal test calculation module is established based on NX TMG for secondary development to complete the heat transfer analysis calculation;

[0027] Step 4: Based on Matlab / Simulink modeling, build digital models of the PID controller and power amplifier. Build the controller model according to the mathematical principles of the PID control algorithm, and build the power amplifier model including linear and nonlinear segments according to the power amplifier principle and measured data. Use the input control point temperature or heat flow curve as the control spectrum and the transient feedback quantity calculated by simulation as the control parameter to realize the closed-loop control of the virtual thermal test and establish the virtual test control module.

[0028] Step 5: The output power of the virtual thermal test control module after power amplification is provided to the virtual thermal test loading module in real time, the thermal load conditions are transmitted to the thermal test calculation module, the thermal analysis calculation of the virtual thermal test is completed, and the heat flux density / temperature data of the control point is sent back to the virtual thermal test control module for closed-loop control calculation.

[0029] Step 6: Based on the above closed-loop system, encapsulate it, design the visualization interface, build the virtual simulation system visualization module, and realize the visualization of the system.

[0030] Preferably, the application process of the system is as follows: the user logs into the virtual test system, creates a virtual test project, imports the virtual test model, applies virtual test loads, performs closed-loop control through the virtual test control module, and after the solution is completed, extracts the result data of relevant virtual measurement points and performs virtual test result post-processing.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] This invention provides a closed-loop virtual simulation system and design method for structural thermal testing, which is used for virtual simulation of the entire process of various structural thermal tests. The virtual simulation system for structural thermal testing has a predictive and guiding role in structural thermal testing. Virtual testing and simulation verification have become the main ways to shorten the development cycle, reduce project risks and development costs. Attached Figure Description

[0033] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0034] Figure 1 This is a schematic diagram of the overall scheme of the closed-loop structural thermal test virtual simulation system and design method of the present invention;

[0035] Figure 2 This is a technical diagram of the closed-loop structural thermal test virtual simulation system and design method of the present invention.

[0036] Figure 3 This is a flowchart illustrating the workflow of the closed-loop structural thermal testing virtual simulation system and design method of the present invention. Detailed Implementation

[0037] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0038] Example:

[0039] This invention provides a closed-loop virtual simulation system and design method for structural thermal testing, which can be used for virtual simulation of the entire process of various structural thermal tests.

[0040] like Figure 1 , Figure 2The diagram shown illustrates the overall scheme and technical scheme of this invention. The virtual simulation system includes a thermal test calculation module, a virtual thermal test loading module, a virtual thermal test control module, a system visualization module, a digital model library, a 3D modeling module, and a model correction module.

[0041] The digital model library is used to classify and manage various three-dimensional numerical models used in virtual simulation of structural thermal testing. It mainly includes a digital material library and various digital models. The types of digital models primarily include heat source models, tooling and fixture models, test bench models, and test specimen models. The digital material library classifies, stores, and manages commonly used material information and characteristic attribute information. Based on the digital model library, various typical structural thermal testing virtual scenarios can be easily built.

[0042] The 3D modeling module models various typical test models for structural thermal tests, and uses the model correction module to correct the models, establish a digital model of the test object, mesh the digital model and assign it material properties from the digital material library, and establish a complete digital model library.

[0043] The virtual thermal test loading module is used for virtual thermal load loading tests, using a heating element (quartz lamp) as the basic unit module. When modeling the heating element, small components such as the lamp head are ignored; the main considerations are the influence of the spiral tungsten filament on the heating power and the reflection and transmission of radiant energy generated by the tungsten filament through the quartz glass tube wall, forming a digital model of the heating element (quartz lamp). Based on the digital model of the heating element (quartz lamp), heat source models for various typical test scenarios are built according to different arrangements of physical quartz lamps.

[0044] The thermoelectric conversion characteristics of the heating element (quartz lamp) in the virtual thermal test loading module are calculated using the resistivity method to obtain the real-time operating voltage parameters of the quartz lamp. The operating temperature of the filament is then calculated using the resistivity method, thereby enabling the application of radiative heat load to the heating element.

[0045] The calculation of the thermal load of the heating element (quartz lamp) specifically includes:

[0046] (1) Obtain the real-time operating voltage of the heating element based on the correspondence between the control output of the physical test control system and the operating voltage of the heating element.

[0047] (2) Calculate the resistivity of the tungsten wire under real-time operating voltage according to the following formula, where ρ is the resistivity of the tungsten wire, s is the cross-sectional area of ​​the tungsten wire, L is the total length of the tungsten wire, t is an empirical parameter (with a value range of 1.5-1.7), P_rated is the rated power of the lamp tube, and U_rated is the rated operating voltage of the lamp tube.

[0048]

[0049] (3) Based on the relationship between resistivity and temperature in the resistivity property table of tungsten metal at different temperatures, temperature interpolation calculation is performed to obtain the filament working temperature under the real-time working voltage.

[0050] (4) The working temperature of the heating element filament is the heat load.

[0051] The virtual thermal test control module is used for closed-loop control of virtual tests. It adopts PID control simulation technology to obtain the PID control simulation method of virtual thermal tests, and its PID controller is a discrete position controller.

[0052] The thermal test calculation module is used for heat transfer analysis calculations in virtual experiments. It employs finite element analysis, using Monte Carlo ray tracing algorithms to analyze the ground radiative thermal environment; computational fluid dynamics (CFD) methods to simulate the comprehensive impact of the ground environment on the model components, particularly the impact of natural convection heat transfer; and computational heat transfer (CHT) methods to analyze the steady-state or transient thermal responses of the test components and fixtures.

[0053] The system visualization module is used for the visual display of virtual experiments. It integrates the digital model library, thermal test calculation module, virtual test loading module, and virtual test control module, constructing a visual interface between each module and the system visualization module. The system visualization module can call the visualization interfaces of each module to achieve functions such as previewing models from the digital model library, previewing virtual test scenarios, real-time display of virtual test control, and displaying virtual test results.

[0054] like Figure 3 The design method for a closed-loop structural thermal test virtual simulation system is as follows:

[0055] (1) Based on the common material properties in structural thermal tests, a digital material library is constructed. At the same time, the test objects are classified according to their characteristics, the key areas are optimized, a digital model of the test object is established, and a mesh is generated to construct a digital model library.

[0056] (2) A digital model of a single quartz lamp as the heating element is established based on the thermoelectric characteristics, radiation characteristics, working time constant, and working temperature of the quartz lamp. A typical heater model is built based on the heating element, and a virtual thermal test loading module is established.

[0057] (3) Taking into account the effects of each test device and the surrounding environment, in addition to the radiant heat emitted by the heater, there are also the effects exerted by the surrounding environment. The environmental boundary includes the air convection environment in the ground test chamber environment, the radiative heat dissipation of the surface of the structural components to the outside, and the additional effects generated by the test fixtures. Based on NX TMG, a secondary development was carried out to establish a thermal test calculation module and complete the heat transfer analysis calculation.

[0058] (4) Based on Matlab\Simulink modeling, build a digital model of PID controller and power amplifier. Build a controller model based on the mathematical principle of PID control algorithm. Build a power amplifier model including linear and nonlinear segments based on the power amplifier principle and measured data. Use the input control point temperature or heat flow curve as the control spectrum and the transient feedback quantity calculated by simulation as the control parameter to realize the closed-loop control of the virtual thermal test and establish a virtual test control module.

[0059] (5) The output power of the virtual thermal test control module after power amplification is provided to the virtual thermal test loading module in real time. The virtual thermal test loading module transmits the thermal load conditions to the thermal test calculation module to complete the thermal analysis calculation of the virtual thermal test. The thermal test calculation module then transmits the heat flux density / temperature data of the control point back to the virtual thermal test control module for closed-loop control calculation.

[0060] (6) Based on the above closed-loop system, encapsulate it, design the visualization interface, build a virtual simulation system visualization module, and realize the visualization of the system.

[0061] The application process of the closed-loop structural thermal test virtual simulation system is as follows: the user logs into the virtual test system, creates a virtual test project, imports the virtual test model, applies virtual test loads, performs closed-loop control through the virtual test control module, and after the solution is completed, extracts the result data of relevant virtual measurement points and performs virtual test result post-processing.

[0062] Those skilled in the art will understand that, in addition to implementing the system, apparatus, and their modules provided by this invention in purely computer-readable program code, the same program can be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system, apparatus, and their modules provided by this invention can be considered a hardware component, and the modules included therein for implementing various programs can also be considered structures within the hardware component; alternatively, modules for implementing various functions can be considered both software programs implementing the method and structures within the hardware component.

[0063] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A closed-loop structural thermal testing virtual simulation system, characterized in that, include: Thermal test calculation module: Uses finite element analysis to perform heat transfer analysis and calculation for virtual tests; Virtual thermal test loading module: Uses heating elements as the basic unit to perform virtual thermal load loading tests; Virtual thermal test control module: performs closed-loop control of the virtual test; System visualization module: Provides a visual representation of the virtual experiment; Digital Model Library: This library categorizes and manages three-dimensional numerical models for virtual simulation of structural thermal tests, including a digital material library and various digital models. 3D modeling module: Models various test models for structural thermal tests, establishes digital models of test objects, meshes the digital models and assigns them material properties from the digital material library, and establishes a complete digital model library; Model correction module: Corrects the established model; The virtual thermal test loading module includes: calculating the thermoelectric conversion characteristics of the heating element quartz lamp using the resistivity method, obtaining the real-time operating voltage parameters of the quartz lamp, calculating the working temperature of the filament using the resistivity method, and thus applying the radiative heat load of the heating element; The virtual thermal test control module includes: a PID control simulation method for obtaining virtual thermal test using PID control simulation technology, and closed-loop control of virtual test, wherein the PID controller is a discrete position controller; The process of calculating the heat load of the quartz lamp heating element specifically includes: obtaining the real-time operating voltage of the heating element based on the correspondence between the control output of the physical test control system and the operating voltage of the heating element; then calculating the resistivity of the tungsten filament of the heating element under the real-time operating voltage; and performing temperature interpolation calculation based on the correspondence between resistivity and temperature in the resistivity property table of tungsten metal at different temperatures to obtain the filament operating temperature under the real-time operating voltage. The operating temperature of the heating element filament is the heat load. The formula for calculating the resistivity of the tungsten wire in a heating element under real-time operating voltage is as follows: Where ρ is the resistivity of the tungsten wire, s is the cross-sectional area of ​​the tungsten wire, L is the total length of the tungsten wire, t is an empirical parameter, P_rated is the rated power of the lamp tube, and U_rated is the rated operating voltage of the lamp tube.

2. The closed-loop structural thermal test virtual simulation system according to claim 1, characterized in that, The thermal test calculation module includes: using the Monte Carlo ray tracing algorithm to analyze the ground radiation thermal environment, using the computational fluid dynamics (CFD) method to simulate the comprehensive impact of the ground environment on the model component, and using the computational heat transfer method CHT to analyze the steady-state or transient thermal response of the test component and test fixture.

3. The closed-loop structural thermal test virtual simulation system according to claim 1, characterized in that, The virtual thermal test loading module includes: modeling a quartz lamp as the heating element, considering the influence of the spiral tungsten filament on the heating power and the reflection and transmission of the radiant energy generated by the tungsten filament by the quartz glass tube wall, forming a digital model of the heating element; and building heat source models for various test scenarios according to different arrangement methods of the physical test quartz lamps based on the digital model of the heating element.

4. The closed-loop structural thermal testing virtual simulation system according to claim 1, characterized in that, The system visualization module includes: previewing models from the digital model library, previewing virtual test scenarios, real-time display of virtual test control, and displaying virtual test results.

5. A closed-loop virtual simulation method for structural thermal testing, characterized in that, Using the closed-loop structural thermal test virtual simulation system according to any one of claims 1-4, the following steps are performed: Step 1: Construct a digital material library based on the common material properties in structural thermal tests, classify the test objects according to their characteristics, optimize the models of key areas, establish digital models of the test objects, mesh them, and construct a digital model library. Step 2: Based on the thermoelectric characteristics, radiation characteristics, working time constant, and working temperature parameters of the quartz lamp, establish a digital model with a single quartz lamp as the heating element, build a heater model based on the heating element, and establish a virtual thermal test loading module. Step 3: Taking into account the effects of each experimental device and the surrounding environment, a thermal test calculation module is established based on NX TMG for secondary development to complete the heat transfer analysis calculation; Step 4: Based on Matlab / Simulink modeling, build digital models of the PID controller and power amplifier. Build the controller model according to the mathematical principles of the PID control algorithm, and build the power amplifier model including linear and nonlinear segments according to the power amplifier principle and measured data. Use the input control point temperature or heat flow curve as the control spectrum and the transient feedback quantity calculated by simulation as the control parameter to realize the closed-loop control of the virtual thermal test and establish the virtual test control module. Step 5: The output power of the virtual thermal test control module after power amplification is provided to the virtual thermal test loading module in real time, the thermal load conditions are transmitted to the thermal test calculation module, the thermal analysis calculation of the virtual thermal test is completed, and the heat flux density / temperature data of the control point is sent back to the virtual thermal test control module for closed-loop control calculation. Step 6: Encapsulate the closed-loop system based on Steps 1 to 5, design the visualization interface, build the virtual simulation system visualization module, and realize the visualization of the system.

6. The closed-loop structural thermal test virtual simulation method according to claim 5, characterized in that, The system's application process is as follows: users log in to the virtual test system, create virtual test projects, import virtual test models, apply virtual test loads, perform closed-loop control through the virtual test control module, and after the solution is completed, extract the result data of relevant virtual measurement points and perform virtual test result post-processing.

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