Multidirectional thermal stress compensation analysis method and system for molten salt tank

Abstract

The invention relates to the technical field of data processing, and discloses a molten salt tank multidirectional thermal stress compensation analysis method and system. Comprising the steps of determining the operation condition of the molten salt tank, collecting comprehensive material parameters, obtaining comprehensive construction parameters of the molten salt tank, constructing a tank body simulation model, constructing an inverted cone region, calculating a calibration height, dividing the molten salt tank into a stress region by taking the region height as a standard, calculating the region thermal stress of the stress region, and generating stress compensation information. According to the invention, the analysis effect of breaking up the whole multidirectional thermal stress of the molten salt tank into parts can be realized, the huge burden caused by multidirectional thermal stress overall compensation analysis is reduced, and a plurality of stress areas can be ensured to be in one-to-one correspondence with spatial positions with different heights and temperatures in the molten salt tank; therefore, the regionalized independent compensation analysis effect of the multidirectional thermal stress in the molten salt tank is achieved, and the purpose of independent, accurate and rapid compensation analysis of the multidirectional thermal stress at different heights and temperature positions of the molten salt tank is achieved.

Description

Technical Field

[0001] The present invention relates to the field of data processing technology, and more particularly to a method and system for analyzing multi-directional thermal stress compensation in a molten salt tank. Background Art

[0002] As the core equipment of the molten salt energy storage system, the molten salt tank is widely used in solar thermal power generation, industrial waste heat storage and other fields. The high-temperature molten salt stored inside it will produce significant thermal stress during the charging and discharging process. The structural materials of the molten salt tank are prone to creep and fatigue damage under high temperature and cyclic thermal loads, and even lead to structural failure. In order to ensure the accuracy of subsequent thermal stress compensation operations on the molten salt tank, it is necessary to accurately compensate for the multi-directional thermal stress of the molten salt tank.

[0003] Patent application CN119358320A discloses a finite element analysis method, system, electronic device, and storage medium for gas tank base stress. The method uses adaptive meshing technology to comprehensively consider stress concentration areas and stress gradient changes, and finely models the gas tank base to obtain a high-quality finite element mesh model. During the meshing process, the method focuses on the mesh density of the stress concentration area under the action of the load, improving the mesh quality in this area to accurately capture the stress gradient changes. A load combination method is used to study the stress distribution law of the gas tank base under the action of multiple load coupling. When conducting multi-directional thermal stress compensation analysis on existing molten salt tanks, an overall thermal stress analysis is performed on the molten salt tank to achieve thermal stress compensation analysis effects in different directions of the molten salt tank. However, treating the molten salt tank as a whole for thermal stress analysis not only leads to a large amount of data calculation, but also makes it difficult to perform independent analysis of the thermal stresses in different height and temperature areas within the molten salt tank. As a result, the multi-directional thermal stress obtained from the compensation analysis cannot be dynamically correlated with the actual thermal stresses in different height and temperature areas within the molten salt tank, reducing the accuracy of the multi-directional thermal stress compensation analysis results of the molten salt tank, and thus failing to meet the molten salt tank's precise requirements for thermal stress compensation in local locations.

[0004] In view of this, the present invention proposes a multi-directional thermal stress compensation analysis method and system for a molten salt tank to solve the above problems. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art and to achieve the above-mentioned objectives, the present invention provides the following technical solution: a multi-directional thermal stress compensation analysis method for a molten salt tank, comprising: S01: Based on the temperature change data within a standard time period, the operating condition of the molten salt tank at the current moment is determined, and the comprehensive material parameters of the molten salt tank are collected. The comprehensive material parameters include elastic modulus, Poisson's ratio and linear thermal expansion coefficient; S02: Obtain comprehensive structural parameters of the molten salt tank, construct a basic model with simulation positions, and integrate comprehensive material parameters with the simulation positions to convert the basic model into a tank simulation model. The comprehensive structural parameters include height, diameter, and wall thickness. S03: Determine the spatial base points of the tank simulation model, construct an inverted cone area based on the spatial base points, collect regional parameters of the inverted cone area, and calculate the calibration height of the tank simulation model. The regional parameters include the regional hypotenuse value and the regional vertical value; S04: Based on the equidistant partitioning principle, the calibrated height is reduced to the regional height, and the molten salt tank is divided into stress regions based on the regional height. The equidistant partitioning principle is that the heights of any two adjacent stress regions are equal. S05: Collect comprehensive stress data of the stress area, calculate the regional thermal stress of the stress area, perform over-limit analysis on the regional thermal stress, and generate stress compensation information.

[0006] Furthermore, the operating conditions include startup conditions, steady-state conditions, and shutdown conditions; The steps to determine the operating conditions are as follows: Query the database for A historical temperature change events of the molten salt tank in the past time period, query the temperature change value and temperature change duration from the A historical temperature change events, and calculate A unit duration after comparing the temperature change value and temperature change duration; The maximum value of the unit time and the minimum value of the unit time are added and averaged to calculate the standard time. Taking the current time as the starting point, the temperature change period is generated by counting back one standard time. Query the temperature values ​​of the molten salt tank at B temperature change moments during the temperature change period, and analyze the change trends of the B temperature values; When the change trend of B temperature values ​​is continuously rising, the molten salt tank is in the starting condition; When the change trend of B temperature values ​​is continuous and gentle, the molten salt tank is in a steady state; When the change trend of the B temperature values ​​is continuously decreasing, the molten salt tank is in a shutdown condition.

[0007] Furthermore, the steps for building the basic model are as follows: The outline of the molten salt tank is constructed in three-dimensional space by using three-dimensional modeling technology, and the outline of the molten salt tank is stretched to expand and deform until the height, diameter and wall thickness of the outline of the molten salt tank reach the height value, diameter value and wall thickness value respectively; Scan the boundary chamfer image of the molten salt tank, and use the boundary chamfer image as a standard to chamfer the boundary of the molten salt tank contour after expansion and deformation to generate a basic model; Three attribute bits with two upper and lower distributed simulation units are established, and the text part of the elastic modulus, the text part of the Poisson's ratio and the text part of the linear thermal expansion coefficient are respectively annotated in the upper simulation unit among the three attribute bits, so that the three attribute bits are converted into the first simulation bit, the second simulation bit and the third simulation bit respectively.

[0008] Furthermore, the conversion steps of the tank simulation model are as follows: Importing the numerical parts of the elastic modulus, Poisson's ratio and linear thermal expansion coefficient into the simulation units located at the bottom of the first simulation position, the second simulation position and the third simulation position respectively; The elastic modulus, Poisson's ratio, linear thermal expansion coefficient, height value, diameter value and wall thickness value are fused with the data fusion algorithm to generate a model parameter set; A remark box is created on the model parameter set, and the operating conditions of the molten salt tank are imported into the remark box to convert the basic model into a tank simulation model.

[0009] Furthermore, the steps for constructing the inverted cone region are as follows: The bottom side wall of the tank simulation model is used as the reference wall, and the center point of the reference wall is marked as the spatial base point; Starting from the spatial base point, draw an auxiliary line perpendicular to the reference wall and extending to the top side wall of the tank simulation model, and record the intersection of the auxiliary line and the top side wall of the tank simulation model as the upper base point; With the above base point as the center and one-third of the diameter as the radius, draw a base point circle on the top side wall of the tank simulation model; A point is randomly selected on the boundary of the base point circle, and a region line is generated by connecting the point with the spatial base point. The spatial base point is controlled to be stationary, and the point is driven to rotate one circle on the base point circle. The area enclosed by the region line is recorded as the inverted cone area.

[0010] Furthermore, the calculation steps for the calibration height are as follows: Mark the midpoint of the auxiliary line, draw an extension line perpendicular to the auxiliary line through the midpoint and intersecting the area line, and mark the intersection of the auxiliary line and the area line as the oblique point; Measure the distance between the spatial base point and the midpoint, and the distance between the spatial base point and the oblique point one by one, and record them as the regional vertical value and the regional oblique value respectively; After comparing the area vertical value with the area hypotenuse value, the slope-to-vertical ratio is calculated, and the slope-to-vertical ratio is multiplied by the unit height value to calculate the calibration height.

[0011] Furthermore, the stress area division steps are as follows: Divide the height value by the calibration height to calculate the calibration multiple; When the calibration multiple is a positive integer, the calibration height is used as the region height, and the molten salt tank is divided into D stress regions starting from the bottom wall of the molten salt tank; When the calibration multiple is not a positive integer, 1% of the calibration height is used as a reduction standard, the calibration height is continuously reduced, and the calibration multiple after reduction is calculated in real time until the calibration multiple after reduction is a positive integer for the first time; The reduced calibration height is recorded as the regional height, and the molten salt tank is divided into D stress regions starting from the bottom side wall of the molten salt tank.

[0012] Furthermore, the comprehensive stress data include regional internal pressure values ​​and regional temperature change values; Regional thermal stress includes axial thermal stress, radial thermal stress and tangential thermal stress.

[0013] Furthermore, the stress compensation information includes axial overrun information, radial overrun information, and tangential overrun information; The steps for generating regional compensation information are as follows: Perform stress over-limit analysis on the axial thermal stress, radial thermal stress and tangential thermal stress of D stress regions one by one; When the axial thermal stress is greater than the axial safety stress, the stress area generates axial overlimit information; When the radial thermal stress is greater than the radial safety stress, the stress area generates radial overlimit information; When the tangential thermal stress is greater than the tangential safety stress, the stress area generates a tangential limit violation message.

[0014] The multi-directional thermal stress compensation analysis system for molten salt tanks is used to implement a multi-directional thermal stress compensation analysis method for molten salt tanks. The system includes a material parameter acquisition module, a simulation model construction module, a calibration height calculation module, a stress area division module, and a stress compensation analysis module. The modules are connected via a wired or wireless network. The material parameter acquisition module is used to determine the operating conditions of the molten salt tank at the current moment based on the temperature change data within a standard time period, and to collect the comprehensive material parameters of the molten salt tank; The simulation model construction module is used to obtain the comprehensive structural parameters of the molten salt tank, build a basic model with simulation positions, and integrate the comprehensive material parameters with the simulation positions to convert the basic model into a tank simulation model; The calibration height calculation module is used to determine the spatial base point of the tank simulation model, construct an inverted cone area based on the spatial base point, collect regional parameters of the inverted cone area, and calculate the calibration height of the tank simulation model; The stress zone division module is used to reduce the calibrated height into zone height based on the equidistant partitioning principle, and divide the molten salt tank into stress zones based on the zone height; The stress compensation analysis module is used to collect comprehensive stress data of the stress area, calculate the regional thermal stress of the stress area, perform over-limit analysis on the regional thermal stress, and generate stress compensation information.

[0015] The technical effects and advantages of the multi-directional thermal stress compensation analysis method and system for molten salt tanks of the present invention are as follows: (1): The present invention collects comprehensive material parameters and comprehensive structural parameters, and combines them with three-dimensional modeling technology to construct a tank simulation model that is consistent with and matches the molten salt tank, thereby providing an accurate model division space basis for the subsequent compensation analysis of the multi-directional thermal stress of the molten salt tank. By constructing an inverted cone area in the tank simulation model, a spatial range with clear boundaries can be provided for the calculation and analysis of the subsequent model division standard, so that the model division standard can play a dynamic correlation role with the actual operating conditions and multi-modal parameters of the molten salt tank, avoiding the phenomenon that the model division standard is isolated and cannot be correlated with the actual situation of the molten salt tank.

[0016] (2): The present invention can reduce the calibration height and convert it into regional height through the equidistant partitioning criterion to ensure that the integral molten salt tank can be divided into multiple stress areas of the same height. It can not only achieve the analysis effect of breaking down the multi-directional thermal stress of the molten salt tank into parts, reduce the huge burden brought by the overall compensation analysis of the multi-directional thermal stress, and improve the accuracy of the subsequent multi-directional thermal stress compensation analysis results, but also ensure that the multiple stress areas can correspond one-to-one to the spatial positions of different heights and temperatures in the molten salt tank, and achieve the independent compensation analysis effect of the multi-directional thermal stress regionalization in the molten salt tank, thereby achieving the purpose of independent, accurate and rapid compensation analysis of the multi-directional thermal stress at different heights and temperature positions of the molten salt tank, and providing accurate theoretical support for the subsequent thermal stress compensation measures of the molten salt tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic flow chart of a multi-directional thermal stress compensation analysis method for a molten salt tank provided in Example 1 of the present invention; Figure 2 This is a module schematic diagram of the multi-directional thermal stress compensation analysis system for a molten salt tank provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0019] Example 1: Please refer to Figure 1As shown, the multi-directional thermal stress compensation analysis method for a molten salt tank in this embodiment includes: S01: Based on the operating condition stability criterion, determine the operating condition of the molten salt tank at the current moment and collect the comprehensive material parameters of the molten salt tank; The operating condition is used to specifically represent the actual operating status of the molten salt tank at the current moment. Since the molten salt tank will experience different dynamic changes under different operating conditions, and the molten salt medium in the molten salt tank will cause different thermal stresses on the tank body during charging and discharging under different operating conditions, the thermal stress distribution of the molten salt tank will also change accordingly. Therefore, it is necessary to determine the operating condition of the molten salt tank; Specifically, the operating conditions include startup conditions, steady-state conditions, and shutdown conditions; The startup condition refers to the stage when the molten salt tank is in the initial startup process, the shutdown condition refers to the stage when the molten salt tank is in the shutdown process, and the steady-state condition refers to the stage when the molten salt tank is in the dynamic stability process. The thermal stress in the molten salt tank under the startup condition and the shutdown condition is not stable, and the thermal stress in the molten salt tank under the steady-state condition is relatively stable.

[0020] When determining the operating condition, in order to ensure the accuracy and authenticity of the operating condition determination results, it is necessary to limit the operating condition determination process in combination with the operating condition stability criterion to improve the accuracy of the current operating condition determination and avoid the phenomenon of misjudgment of the operating condition; Specifically, the operating condition stability maintenance criterion is: based on the temperature change data within a standard time period; the temperature change of the molten salt tank within a specific time period can be accurately represented, and sufficient and reasonable temperature data can be provided for the subsequent determination of the actual operating conditions.

[0021] The steps to determine the operating conditions are as follows: A historical temperature change event of the molten salt tank in the past time period is queried from the database. The temperature change value and temperature change duration are queried from the A historical temperature change events. After comparing the temperature change value and temperature change duration, A unit duration is calculated. The historical temperature change event is used to comprehensively summarize and store the temperature change data of the molten salt tank in the past time period, and provides the necessary data basis for determining the duration of subsequent operating conditions. The calculation formula for unit duration is: ; Where, For the The unit duration of a historical temperature change event, =1,2...A, For the The duration of temperature change in historical temperature change events, For the The temperature change value of a historical temperature change event; The maximum value of the unit duration and the minimum value of the unit duration are added together and averaged to calculate the standard duration; The formula for calculating the standard duration is: ; Where, For standard duration, is the maximum value of the unit duration, is the minimum value of the unit duration; Taking the current moment as the starting point, the temperature change period is generated after a standard time period is counted back. This allows the temperature change period to provide a time dimension basis for determining and analyzing the operating conditions. Query the temperature values ​​of the molten salt tank at B temperature change moments during the temperature change period and analyze the change trends of the B temperature values. The change trend is used to represent the overall change of the temperature value of the molten salt tank during the temperature change period, so as to determine the magnitude of the change in the temperature value of the molten salt tank during the temperature change period. Specifically, the change trend includes continuous increase, continuous flatness and continuous decrease. When the change trend of the B temperature values ​​is continuously rising, the temperature in the molten salt tank is in a gradually rising stage, and the molten salt tank is in the starting condition; When the change trend of B temperature values ​​is continuously slow, the temperature in the molten salt tank is in a gradually slow stage, and the molten salt tank is in a steady state; When the change trend of the B temperature values ​​is continuously decreasing, the temperature in the molten salt tank is in a stage of gradually decreasing, and the molten salt tank is in a shutdown condition.

[0022] After determining the operating conditions of the molten salt tank, the changing properties of the multi-directional thermal stress in the molten salt tank during the storage and utilization of the molten salt medium at the current moment are clarified, which can provide a basic limitation for the subsequent compensation analysis of the multi-directional thermal stress of the molten salt tank; In order to ensure the accuracy of the subsequent multi-directional thermal stress compensation analysis, it is necessary to collect the comprehensive material parameters of the molten salt tank. The comprehensive material parameters here refer to the parameters of the manufacturing materials of the molten salt tank itself that can affect the changes in multi-directional thermal stress. The comprehensive material parameters can provide an analysis basis for the multi-directional thermal stress changes of the molten salt tank in terms of material properties. Specifically, the comprehensive material parameters include elastic modulus, Poisson's ratio, and linear thermal expansion coefficient; The elastic modulus is the ratio of stress to strain in a material during elastic deformation, and is used to describe the material's ability to resist elastic deformation. The Poisson's ratio is the ratio of lateral strain to axial strain when the material is subjected to unidirectional force, and reflects the lateral deformation characteristics of the material under force. The linear thermal expansion coefficient describes the sensitivity of the material to length changes when the temperature changes.

[0023] The specific values ​​of the elastic modulus, Poisson's ratio, and linear thermal expansion coefficient will vary depending on the manufacturing material of the molten salt tank itself. When collecting the elastic modulus, Poisson's ratio, and linear thermal expansion coefficient of the molten salt tank, it is necessary to clarify the material of the molten salt tank and the current temperature, and then obtain them through technical manuals, international standards, etc.

[0024] S02: Obtain comprehensive structural parameters of the molten salt tank, construct a basic model with simulation positions, and integrate the comprehensive material parameters with the simulation positions to convert the basic model into a tank simulation model; In order to ensure the accuracy of the subsequent multi-directional thermal stress compensation analysis, it is also necessary to collect the comprehensive structural parameters of the molten salt tank. The comprehensive structural parameters here refer to the parameters of the structural shape of the molten salt tank itself that can affect the multi-directional thermal stress changes. The comprehensive structural parameters can provide an analysis basis for the multi-directional thermal stress changes of the molten salt tank in terms of structural shape; Specifically, the comprehensive structural parameters include height value, diameter value and wall thickness value; the height value is used to represent the overall height of the molten salt tank, the diameter value is used to represent the diameter size of the bottom and top of the molten salt tank, and the wall thickness value is used to represent the thickness of the tank wall of the molten salt tank; in this embodiment, the height value, diameter value and wall thickness value are obtained by querying the design drawings of the molten salt tank.

[0025] After obtaining the comprehensive structural parameters, a basic model matching the molten salt tank can be constructed using the comprehensive structural parameters through 3D modeling technology, thereby representing the structural characteristics of the molten salt tank in 3D space. Specifically, the steps for building the basic model are as follows: The outline of the molten salt tank is constructed in three-dimensional space using three-dimensional modeling technology, and the outline of the molten salt tank is stretched to expand and deform until the height, diameter, and wall thickness of the outline of the molten salt tank reach the height value, diameter value, and wall thickness value, respectively. The stretching and deformation operation can increase the length, height, and diameter of the initially constructed outline of the molten salt tank so that they are equal to the actual height value, diameter value, and wall thickness value of the molten salt tank. Scan the edge chamfer image of the molten salt tank and use it as a standard to chamfer the edge of the expanded and deformed molten salt tank to generate a basic model. The edge chamfer refers to the position of the edge contour line of the molten salt tank. By chamfering the boundary, the smoothness of the edge contour line position of the basic model can be ensured. Three attribute bits with two upper and lower distributed simulation units are established, and the text part of the elastic modulus, the text part of the Poisson's ratio and the text part of the linear thermal expansion coefficient are respectively annotated in the upper simulation unit among the three attribute bits, so that the three attribute bits are converted into the first simulation bit, the second simulation bit and the third simulation bit respectively.

[0026] After obtaining the basic model, the basic model can only represent the structural shape of the molten salt tank, but cannot represent the changes in material properties to multi-directional thermal stress. Therefore, it is necessary to integrate the comprehensive material parameters with the simulation position of the basic model to obtain a tank simulation model. This allows the tank simulation model to provide accurate model support for the compensation analysis of the multi-directional thermal stress of the molten salt tank in terms of structural form and material properties. Specifically, the conversion steps of the tank simulation model are as follows: Importing the numerical parts of the elastic modulus, Poisson's ratio and linear thermal expansion coefficient into the simulation units located at the bottom of the first simulation position, the second simulation position and the third simulation position respectively; The elastic modulus, Poisson's ratio, and linear thermal expansion coefficient are fused with the height, diameter, and wall thickness values ​​through a data fusion algorithm to generate a model parameter set. The data fusion algorithm is an information processing technology that aims to automatically analyze and integrate data from different sources, formats, or time points to form a more comprehensive and accurate basis for decision-making. In this embodiment, the data fusion algorithm can be used to fuse the multimodal data parameters in the molten salt tank to achieve a dynamic correlation effect of the multimodal data parameters. A remark box is created on the model parameter set, and the operating conditions of the molten salt tank are imported into the remark box to convert the basic model into a tank simulation model.

[0027] It should be noted that the constructed tank simulation model can be consistent with the actual molten salt tank in terms of structural form and material properties, thereby providing real and accurate model support for the subsequent compensation analysis of the multi-directional thermal stress of the molten salt tank.

[0028] S03: Determine the spatial base points of the tank simulation model, construct an inverted cone area based on the spatial base points, collect regional parameters of the inverted cone area, and calculate the calibration height of the tank simulation model; After the tank simulation model is constructed, it can be used as a one-to-one simulation model of the molten salt tank in three-dimensional space, so that the tank simulation model can play an integral simulation effect on the multi-directional thermal stress of the molten salt tank. Since the temperature values ​​corresponding to different height positions inside the molten salt tank are inconsistent, the thermal stress values ​​at different height positions of the molten salt tank are also inconsistent. Therefore, the integral multi-directional thermal stress analysis operation has limitations, and the tank simulation model needs to be partitioned according to specific rules. When partitioning the tank simulation model, it is necessary to first determine the partition basis of the tank simulation model, that is, the specific height of the tank simulation model partition. When determining the specific height of the partition, first use the tank simulation model as a basis to perform corresponding data collection and calculation processing.

[0029] Specifically, when determining the specific height of the partition, it is necessary to determine the inverted cone area in the tank simulation model and use the inverted cone area as the analysis object to calculate the subsequent partition height; In this embodiment, the inverted cone area is an area in the tank simulation model that has an inverted cone structure. Before constructing the inverted cone area, a spatial base point must be determined in the tank simulation model, and the spatial base point can be used as the initial position for constructing the inverted cone area.

[0030] Specifically, the steps for constructing the inverted cone area are as follows: The bottom side wall of the tank simulation model is used as the reference wall, and the center point of the reference wall is marked as the spatial base point; Starting from the spatial base point, draw an auxiliary line perpendicular to the reference wall and extending to the top side wall of the tank simulation model, and record the intersection of the auxiliary line and the top side wall of the tank simulation model as the upper base point; With the above base point as the center and one-third of the diameter as the radius, draw a base point circle on the top side wall of the tank simulation model; A point is randomly selected on the boundary of the base point circle, and a region line is generated by connecting the point with the spatial base point. The spatial base point is controlled to be stationary, and the point is driven to rotate one circle on the base point circle. The area enclosed by the region line is recorded as the inverted cone area.

[0031] The constructed inverted cone area is an inverted cone structure area. By collecting and analyzing the regional parameters in the inverted cone area, the height calibration height can be provided for the subsequent partitioning of the tank simulation model. The regional parameters are used to measure the boundary parameters of different positions and inclination amplitudes in the inverted cone area. By collecting and calculating the boundary parameters, the calibration height of the tank simulation model can be calculated. Specifically, the region parameters include a region hypotenuse value and a region vertical value; the region hypotenuse value is used to represent the boundary length of the inverted cone region in an inclined state, and the region vertical value is used to represent the boundary length of the inverted cone region in a vertical state.

[0032] The calculation steps for the calibration height are as follows: Mark the midpoint of the auxiliary line, draw an extension line perpendicular to the auxiliary line through the midpoint and intersecting the area line, and mark the intersection of the auxiliary line and the area line as the oblique point; Measure the distance between the spatial base point and the midpoint, and the distance between the spatial base point and the oblique point one by one, and record them as the regional vertical value and the regional oblique value respectively; After comparing the vertical value of the area with the hypotenuse value of the area, the slope-to-vertical ratio is calculated, and the slope-to-vertical ratio is multiplied by the unit height value to calculate the calibration height; the unit height value refers to a preset unit size height value, and the unit height value is set according to actual needs. For example, the unit height value is 1M; The calculation formula for the calibration height is: ; Where, To calibrate the height, is the unit height value, is the area hypotenuse value, is the vertical value of the area.

[0033] It should be noted that the calculated calibration height is only used as the initial numerical basis for partitioning the tank simulation model. When actually partitioning the tank simulation model, the numerical value of the calibration height can be maintained unchanged or reduced to meet the partitioning requirements of the tank simulation model.

[0034] S04: Based on the equidistant partitioning principle, the calibrated height is converted into regional height, and the molten salt tank is divided into stress areas based on the regional height; After calculating the calibration height, it is necessary to further analyze the calibration height to determine whether the calibration height can be used to divide the molten salt tank into equal parts, and record the specific value that satisfies the equal division of the molten salt tank as the regional height to ensure that the regional height is converted based on the calibration height.

[0035] When converting the calibrated height into the regional height, it is necessary to do so under the constraint of the equidistant partitioning principle to ensure the accuracy and rationality of the regional height and to ensure that the heights of the stress regions obtained by subsequent molten salt tank partitioning are consistent. Specifically, the equidistant partitioning criterion is: the heights of any two adjacent stress regions are equal; this ensures that the molten salt tank can be evenly divided into multiple stress regions of equal height.

[0036] The stress area refers to the area within a specific height range obtained by dividing the molten salt tank according to the regional height standard, and serves as the direct object of the subsequent compensation analysis of the multi-directional thermal stress of the molten salt tank.

[0037] The steps for dividing the stress area are as follows: Divide the height value by the calibration height to calculate the calibration multiple; When the calibration multiple is a positive integer, the calibration height is used as the region height, and the molten salt tank is divided into D stress regions starting from the bottom wall of the molten salt tank; When the calibration multiple is not a positive integer, 1% of the calibration height is used as a reduction standard, the calibration height is continuously reduced, and the calibration multiple after reduction is calculated in real time until the calibration multiple after reduction is a positive integer for the first time; The reduced calibration height is recorded as the regional height, and the molten salt tank is divided into D stress regions starting from the bottom side wall of the molten salt tank.

[0038] It should be noted that the divided stress areas are used to provide real regional position limitations for the molten salt tank in subsequent multi-directional thermal stress compensation analysis, and to ensure that the collection and analysis operations of relevant data in the molten salt tank can correspond to the stress areas.

[0039] S05: Collect comprehensive stress data of the stress area, calculate the regional thermal stress of the stress area, perform over-limit analysis on the regional thermal stress, and generate stress compensation information; Comprehensive stress data refers to the comprehensive data that can affect the distribution and magnitude of multi-directional thermal stress in the molten salt tank at the spatial position corresponding to the stress area, thereby providing a comprehensive data basis for the multi-directional thermal stress compensation analysis at different height positions in the molten salt tank; Comprehensive stress data include regional internal pressure value and regional temperature change value; The regional internal pressure value refers to the pressure value inside the tank at the corresponding height position of different stress areas in the molten salt tank, which can represent the size of the molten salt medium and air pressure at different height positions in the molten salt tank; the regional internal pressure value is obtained by detecting the pressure transmitter installed in the molten salt tank.

[0040] The regional temperature variation value refers to the temperature variation value inside the tank body at the height positions corresponding to different stress areas in the molten salt tank, which can represent the temperature variation at different height positions in the molten salt tank. When collecting the regional temperature variation value of the stress area, it is obtained by detecting with a fiber optic temperature sensor installed at the corresponding position of the stress area in the molten salt tank.

[0041] After collecting the comprehensive stress data, the comprehensive stress parameters and comprehensive material parameters can be combined to calculate the thermal stress in each direction of the stress area, and the thermal stress components in all directions are recorded as regional thermal stress; Specifically, regional thermal stress includes axial thermal stress, radial thermal stress and tangential thermal stress; Among them, axial thermal stress refers to the thermal stress caused by the expansion amount due to temperature changes at different positions in the stress area along the height direction of the molten salt tank; The calculation formula for axial thermal stress is: ; Where, is the axial thermal stress, is the elastic modulus, is the linear thermal expansion coefficient, is the temperature change between the top and bottom of the stress region, is Poisson's ratio, is the regional internal pressure value, is the diameter value, is the wall thickness value.

[0042] Radial thermal stress refers to the thermal stress caused by uneven heating along the circumference of the molten salt tank; The calculation formula for radial thermal stress is: ; Where, is the radial thermal stress, is the regional temperature change between one side and the other side of the stress area.

[0043] Tangential thermal stress refers to the shear stress generated by the uncoordinated multi-directional expansion at the welded joints or flange connections on the molten salt tank; The calculation formula of tangential thermal stress is: ; Where, is the tangential thermal stress, is the temperature change between one side of the weld and the other side of the stress area, is the weld thickness, is the weld length.

[0044] When calculating tangential thermal stress, it is necessary to first determine whether there are welds caused by welded joints or flange connections in the stress area, and use camera vision technology to measure the length and thickness of the weld to meet the calculation requirements of tangential thermal stress.

[0045] After calculating the axial thermal stress, radial thermal stress, and tangential thermal stress, a compensation analysis can be performed on the calculation results to determine whether the magnitude of the axial thermal stress, radial thermal stress, and tangential thermal stress in each stress area exceeds the preset thermal stress. Based on the analysis and comparison results, regional stress compensation information corresponding to the stress area is generated to provide the necessary data theoretical support for the subsequent thermal stress compensation of the molten salt tank; Specifically, the stress compensation information includes axial overrun information, radial overrun information, and tangential overrun information; axial overrun information refers to the phenomenon that the axial thermal stress in the stress area exceeds the limit. At this time, the axial thermal stress in the stress area is too large, and the molten salt tank corresponding to the stress area is more likely to deform and crack. Similarly, the radial overrun information and tangential overrun information correspond to the radial thermal stress and tangential thermal stress in the stress area, respectively.

[0046] The steps for generating regional compensation information are as follows: Perform stress over-limit analysis on the axial thermal stress, radial thermal stress and tangential thermal stress of D stress regions one by one; When the axial thermal stress is greater than the axial safety stress, it means that the axial thermal stress of the stress area exceeds the axial thermal stress in the safe state, and the stress area generates axial overlimit information. The axial safety stress refers to the maximum value of the axial thermal stress when the stress area is in the safe state. The axial safety stress is obtained by collecting a large number of historical maximum values ​​of the axial thermal stress when the stress area is in the safe state and calculating their average value. When the radial thermal stress is greater than the radial safety stress, it means that the radial thermal stress of the stress area exceeds the radial thermal stress in the safe state, and the stress area generates radial overrun information. The radial safety stress refers to the maximum radial thermal stress when the stress area is in the safe state. The radial safety stress is obtained by collecting a large number of historical maximum radial thermal stress values ​​of the stress area in the safe state and calculating their average value. When the tangential thermal stress is greater than the tangential safety stress, it indicates that the tangential thermal stress in the stress region exceeds the tangential thermal stress in a safe state, and a tangential overrun message is generated for that stress region. The tangential safety stress refers to the maximum tangential thermal stress when the stress region is in a safe state. The tangential safety stress is obtained by collecting a large number of historical maximum tangential thermal stress values ​​for the stress region when it is in a safe state and calculating the average value.

[0047] It should be noted that the number of regional compensation information that appears in each stress region is not unique and may be 0 or 3. When the number of regional compensation information is 0, it means that the thermal stress in the axial, radial, and tangential directions of the stress region does not exceed the maximum thermal stress in the safe state. The thermal stress of the stress region is in a safe state and no subsequent thermal stress compensation operation is required for the stress region. When the amount of regional compensation information is not 0, it is necessary to clarify which specific objects in the stress area exceed the safety stress, namely the axial thermal stress, radial thermal stress, and tangential thermal stress, and perform subsequent targeted compensation analysis operations on the specific objects exceeding the safety stress.

[0048] Example 2: Please refer to Figure 2 As shown, for the parts not described in detail in this embodiment, please refer to the description of the first embodiment. A multi-directional thermal stress compensation analysis system for a molten salt tank is provided, which is used to implement the multi-directional thermal stress compensation analysis system for a molten salt tank, including a material parameter acquisition module, a simulation model construction module, a calibration height calculation module, a stress area division module and a stress compensation analysis module, wherein the modules are connected to each other via a wired or wireless network; The material parameter acquisition module is used to determine the operating conditions of the molten salt tank at the current moment based on the temperature change data within a standard time period, and to collect the comprehensive material parameters of the molten salt tank; The simulation model construction module is used to obtain the comprehensive structural parameters of the molten salt tank, build a basic model with simulation positions, and integrate the comprehensive material parameters with the simulation positions to convert the basic model into a tank simulation model; The calibration height calculation module is used to determine the spatial base point of the tank simulation model, construct an inverted cone area based on the spatial base point, collect regional parameters of the inverted cone area, and calculate the calibration height of the tank simulation model; The stress zone division module is used to reduce the calibrated height into zone height based on the equidistant partitioning principle, and divide the molten salt tank into stress zones based on the zone height; The stress compensation analysis module is used to collect comprehensive stress data of the stress area, calculate the regional thermal stress of the stress area, perform over-limit analysis on the regional thermal stress, and generate stress compensation information.

[0049] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the scope of protection of the present invention.

Claims

1. The multi-directional thermal stress compensation analysis method of molten salt tank is characterized by: include: S01: Based on the temperature change data within a standard time period, the operating condition of the molten salt tank at the current moment is determined, and the comprehensive material parameters of the molten salt tank are collected. The comprehensive material parameters include elastic modulus, Poisson's ratio and linear thermal expansion coefficient; S02: Obtain comprehensive structural parameters of the molten salt tank, construct a basic model with simulation positions, and integrate comprehensive material parameters with the simulation positions to convert the basic model into a tank simulation model. The comprehensive structural parameters include height, diameter, and wall thickness. S03: Determine the spatial base points of the tank simulation model, construct an inverted cone area based on the spatial base points, collect regional parameters of the inverted cone area, and calculate the calibration height of the tank simulation model. The regional parameters include the regional hypotenuse value and the regional vertical value; S04: Based on the equidistant partitioning principle, the calibrated height is reduced to the regional height, and the molten salt tank is divided into stress regions based on the regional height. The equidistant partitioning principle is that the heights of any two adjacent stress regions are equal. S05: Collect comprehensive stress data of the stress area, calculate the regional thermal stress of the stress area, perform over-limit analysis on the regional thermal stress, and generate stress compensation information.

2. The multi-directional thermal stress compensation analysis method for a molten salt tank according to claim 1 is characterized in that: Operating conditions include startup conditions, steady-state conditions, and shutdown conditions; The steps to determine the operating conditions are as follows: Query the database for A historical temperature change events of the molten salt tank in the past time period, query the temperature change value and temperature change duration from the A historical temperature change events, and calculate A unit duration after comparing the temperature change value and temperature change duration; The maximum value of the unit time and the minimum value of the unit time are added and averaged to calculate the standard time. Taking the current time as the starting point, the temperature change period is generated by counting back one standard time. Query the temperature values ​​of the molten salt tank at B temperature change moments during the temperature change period, and analyze the change trends of the B temperature values; When the change trend of B temperature values ​​is continuously rising, the molten salt tank is in the starting condition; When the change trend of B temperature values ​​is continuous and gentle, the molten salt tank is in a steady state; When the change trend of the B temperature values ​​is continuously decreasing, the molten salt tank is in a shutdown condition.

3. The multi-directional thermal stress compensation analysis method for a molten salt tank according to claim 2, characterized in that: The steps to build the basic model are as follows: The outline of the molten salt tank is constructed in three-dimensional space by using three-dimensional modeling technology, and the outline of the molten salt tank is stretched to expand and deform until the height, diameter and wall thickness of the outline of the molten salt tank reach the height value, diameter value and wall thickness value respectively; Scan the boundary chamfer image of the molten salt tank, and use the boundary chamfer image as a standard to chamfer the boundary of the molten salt tank contour after expansion and deformation to generate a basic model; Three attribute bits with two upper and lower distributed simulation units are established, and the text part of the elastic modulus, the text part of the Poisson's ratio and the text part of the linear thermal expansion coefficient are respectively annotated in the upper simulation unit among the three attribute bits, so that the three attribute bits are converted into the first simulation bit, the second simulation bit and the third simulation bit respectively.

4. The multi-directional thermal stress compensation analysis method for a molten salt tank according to claim 3 is characterized in that: The conversion steps of the tank simulation model are as follows: Importing the numerical parts of the elastic modulus, Poisson's ratio and linear thermal expansion coefficient into the simulation units located at the bottom of the first simulation position, the second simulation position and the third simulation position respectively; The elastic modulus, Poisson's ratio, linear thermal expansion coefficient, height value, diameter value and wall thickness value are fused with the data fusion algorithm to generate a model parameter set; A remark box is created on the model parameter set, and the operating conditions of the molten salt tank are imported into the remark box to convert the basic model into a tank simulation model.

5. The multi-directional thermal stress compensation analysis method for a molten salt tank according to claim 4 is characterized in that: The steps for constructing the inverted cone region are as follows: The bottom side wall of the tank simulation model is used as the reference wall, and the center point of the reference wall is marked as the spatial base point; Starting from the spatial base point, draw an auxiliary line perpendicular to the reference wall and extending to the top side wall of the tank simulation model, and record the intersection of the auxiliary line and the top side wall of the tank simulation model as the upper base point; With the above base point as the center and one-third of the diameter as the radius, draw a base point circle on the top side wall of the tank simulation model; A point is randomly selected on the boundary of the base point circle, and a region line is generated by connecting the point with the spatial base point. The spatial base point is controlled to be stationary, and the point is driven to rotate one circle on the base point circle. The area enclosed by the region line is recorded as the inverted cone area.

6. The multi-directional thermal stress compensation analysis method for a molten salt tank according to claim 5, characterized in that: The calculation steps for the calibration height are as follows: Mark the midpoint of the auxiliary line, draw an extension line perpendicular to the auxiliary line through the midpoint and intersecting the area line, and mark the intersection of the auxiliary line and the area line as the oblique point; Measure the distance between the spatial base point and the midpoint, and the distance between the spatial base point and the oblique point one by one, and record them as the regional vertical value and the regional oblique value respectively; After comparing the area vertical value with the area hypotenuse value, the slope-to-vertical ratio is calculated, and the slope-to-vertical ratio is multiplied by the unit height value to calculate the calibration height.

7. The multi-directional thermal stress compensation analysis method for a molten salt tank according to claim 6, characterized in that: The steps for dividing the stress area are as follows: Divide the height value by the calibration height to calculate the calibration multiple; When the calibration multiple is a positive integer, the calibration height is used as the region height, and the molten salt tank is divided into D stress regions starting from the bottom wall of the molten salt tank; When the calibration multiple is not a positive integer, 1% of the calibration height is used as a reduction standard, the calibration height is continuously reduced, and the calibration multiple after reduction is calculated in real time until the calibration multiple after reduction is a positive integer for the first time; The reduced calibration height is recorded as the regional height, and the molten salt tank is divided into D stress regions starting from the bottom side wall of the molten salt tank.

8. The multi-directional thermal stress compensation analysis method for a molten salt tank according to claim 7, characterized in that: Comprehensive stress data include regional internal pressure value and regional temperature change value; Regional thermal stress includes axial thermal stress, radial thermal stress and tangential thermal stress.

9. The multi-directional thermal stress compensation analysis method for a molten salt tank according to claim 8, characterized in that: The stress compensation information includes axial overrun information, radial overrun information and tangential overrun information; The steps for generating regional compensation information are as follows: Perform stress over-limit analysis on the axial thermal stress, radial thermal stress and tangential thermal stress of D stress regions one by one; When the axial thermal stress is greater than the axial safety stress, the stress area generates axial overlimit information; When the radial thermal stress is greater than the radial safety stress, the stress area generates radial overlimit information; When the tangential thermal stress is greater than the tangential safety stress, the stress area generates a tangential limit violation message.

10. A multi-directional thermal stress compensation analysis system for a molten salt tank, used to implement the multi-directional thermal stress compensation analysis method for a molten salt tank according to any one of claims 1 to 9, characterized in that: It includes a material parameter acquisition module, a simulation model construction module, a calibration height calculation module, a stress area division module and a stress compensation analysis module, wherein each module is connected via a wired or wireless network; The material parameter acquisition module is used to determine the operating conditions of the molten salt tank at the current moment based on the temperature change data within a standard time period, and to collect the comprehensive material parameters of the molten salt tank; The simulation model construction module is used to obtain the comprehensive structural parameters of the molten salt tank, build a basic model with simulation positions, and integrate the comprehensive material parameters with the simulation positions to convert the basic model into a tank simulation model; The calibration height calculation module is used to determine the spatial base point of the tank simulation model, construct an inverted cone area based on the spatial base point, collect regional parameters of the inverted cone area, and calculate the calibration height of the tank simulation model; The stress zone division module is used to reduce the calibrated height into zone height based on the equidistant partitioning principle, and divide the molten salt tank into stress zones based on the zone height; The stress compensation analysis module is used to collect comprehensive stress data of the stress area, calculate the regional thermal stress of the stress area, perform over-limit analysis on the regional thermal stress, and generate stress compensation information.

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