Thick-walled structure temperature change working condition thermal stress protection device
By designing protective devices for the metal shell, electric heating components, and cooling components on the thick-walled structure, the temperature field is actively adjusted, solving the thermal stress problem of the thick-walled structure under variable temperature conditions, extending the equipment life and reducing operating costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TSINGHUA UNIVERSITY
- Filing Date
- 2023-05-12
- Publication Date
- 2026-05-19
AI Technical Summary
Existing technologies cannot effectively protect against thermal stress under variable temperature conditions in thick-walled structures, leading to fatigue damage and cracks in the equipment. Furthermore, they cannot avoid large thermal stresses under unplanned rapid temperature changes, increasing operating costs.
Design a protective device comprising a metal shell, an electric heating component, a cooling component, an insulation layer, a measurement system, and a control system. By actively heating or cooling, the temperature of the non-working surface of the thick-walled structure is regulated to achieve temperature field uniformity and reduce thermal stress and fatigue damage.
It effectively extends the service life of thick-walled structures, is suitable for large and rapid temperature changes, has a compact structure, is easy to transport and install, and reduces thermal stress without affecting other functions of the equipment.
Smart Images
Figure CN116497186B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of operation and maintenance technology for high-temperature and high-pressure equipment, and in particular to a thermal stress protection device for thick-walled structures operating under variable temperature conditions. Background Technology
[0002] High-temperature and high-pressure equipment is widely used in industries such as nuclear power, thermal power, chemical industry, petroleum, and metallurgy. To withstand the high temperatures and pressures, the key components of this equipment are all thick-walled metal structures. Under variable-temperature conditions, the working surfaces of these thick-walled structures frequently experience significant and rapid temperature changes. For example, during the start-up and shutdown of a steam generator in a nuclear power plant, the inner wall of the steam outlet nozzle changes dramatically with the fluid temperature, while the temperature change of the outer wall of the nozzle is very slow. Due to the large wall thickness, the temperature response time of non-working surfaces after the working surface temperature changes is long, resulting in a large temperature gradient perpendicular to the wall surface and causing significant thermal stress. After experiencing multiple variable-temperature conditions, fatigue damage will occur inside the structure, and in severe cases, cracks will appear, leading to equipment failure and huge losses.
[0003] Currently, the main measure to control thermal stress in thick-walled structures under variable temperature conditions is to slow down the rate of temperature rise and fall, making it close to or even lower than the rate of heat diffusion within the structure. One drawback is that it significantly prolongs the duration of the variable temperature condition, increasing operating costs. Another drawback is that under unplanned rapid temperature changes due to misoperation or accidents, thick-walled structures will inevitably suffer large thermal stresses. Summary of the Invention
[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one object of the present invention is to provide a thermal stress protection device for thick-walled structures under variable temperature conditions, which can extend the service life of thick-walled structures and has a compact structure.
[0005] A thermal stress protection device for thick-walled structures under variable temperature conditions according to an embodiment of the present invention includes:
[0006] A metal housing, comprising an outer shell and an inner partition; the outer shell covers a non-working surface of a thick-walled structure, and the outer shell is provided with a cooling medium inlet and a cooling medium outlet; the inner partition is disposed inside the outer shell, dividing the internal space of the outer shell into an independent inner space and an outer space, the outer space being connected to the cooling medium inlet and the cooling medium outlet;
[0007] An electric heating assembly is disposed in the inner space;
[0008] A cooling assembly, the cooling assembly including the outer space and a cooling medium flowing through the outer space;
[0009] A heat insulation layer, which covers the outer surface of the metal casing;
[0010] The measurement system is used to measure the working surface temperature, non-working surface temperature, and cooling fluid flow rate of the thick-walled structure in real time.
[0011] A power supply system is used to provide power to the electric heating assembly;
[0012] The control system controls the flow rate of the cooling medium or the electric heating power according to the working surface temperature of the thick-walled structure, so that the non-working surface temperature of the thick-walled structure reaches the target value.
[0013] The thermal stress protection device for thick-walled structures under variable temperature conditions according to embodiments of the present invention has the following advantages: First, since it simultaneously possesses heating and cooling functions, it can select active heating or active cooling based on the temperature change state of the working surface of the thick-walled structure, automatically adjusting the temperature of the non-working surface, resulting in a more uniform internal temperature field of the thick-walled structure, thereby reducing thermal stress, reducing fatigue damage, and extending the service life of the thick-walled structure; Second, it can automatically adjust the temperature of the non-working surface based on the working surface temperature and its changing trend of the thick-walled structure through a measurement and control system, enabling it to quickly and accurately reach the target temperature, making it suitable for large-amplitude and rapid temperature change conditions, overcoming the shortcomings of current measures; Third, in addition to reducing the thermal stress of the thick-walled structure, it does not affect other functions and characteristics of the thick-walled structure; Fourth, the cooling component and the electric heating component are integrated in the same metal housing, resulting in a compact structure that facilitates transportation and installation.
[0014] In some embodiments, when the working surface of the thick-walled structure heats up, the cooling component stops working and the electric heating component is activated to heat the surface of the thick-walled structure; when the working surface of the thick-walled structure cools down, the electric heating component stops working and the cooling component is activated to cool the surface of the thick-walled structure; when the temperature of the working surface of the thick-walled structure is constant, both the cooling component and the electric heating component stop working, and the insulation layer keeps the thick-walled structure warm.
[0015] In some embodiments, the electric heating assembly is made of a material with high thermal conductivity.
[0016] In some embodiments, the electric heating assembly includes a heating element, a limiting block, and a filler. The heating element is fixed in the inner space by the limiting block. The heating element is electrically connected to the power supply system. The filler fills the remaining gap in the inner space after the limiting block and the heating element are set.
[0017] In some embodiments, there are multiple limiting blocks, which are fixed in the inner space at intervals along the axial direction of the thick-walled structure. Each of the multiple limiting blocks is provided with a through hole, through which the heating element is fixed.
[0018] In some embodiments, the heating element is in the form of a sheet.
[0019] In some embodiments, the heating element is a thin sheet made of high-temperature resistant metal or graphite.
[0020] In some embodiments, the limiting block is made of corundum.
[0021] In some embodiments, the filler is magnesium oxide or boron nitride.
[0022] In some embodiments, the cooling assembly further includes a plurality of fins fixed at intervals to the inner partition.
[0023] In some embodiments, the measurement system includes a flow meter, a temperature sensor, and a data acquisition system; wherein the flow meter is installed on the upstream pipe of the cooling medium inlet to measure the flow rate of the cooling medium entering the outer space; the temperature sensor is distributed at the working surface and non-working surface of the thick-walled structure to measure the temperature at the working surface and non-working surface of the thick-walled structure in real time; the data acquisition system is used to acquire data from the flow meter and the temperature sensor; the control system includes a control cabinet and a regulating valve; the control cabinet is communicatively connected to the data acquisition system to receive data from the flow meter and the temperature sensor transmitted by the data acquisition system in real time; the regulating valve is communicatively connected to the control cabinet to provide feedback and adjust the valve opening located between the cooling medium inlet and the flow meter; the power supply system is equipped with a thyristor voltage regulator and communicates with the control cabinet, and the output voltage can be automatically adjusted by a program.
[0024] In some embodiments, a thermal pad is also included, which is laid between the housing and the thick-walled structure.
[0025] In some embodiments, the insulation layer is made of a high-temperature resistant heat-insulating material.
[0026] In some embodiments, there are multiple metal housings, which form a combined metal housing. The structural dimensions of the multiple metal housings, the cooling power of the corresponding cooling components and the heating power of the heating components within the multiple metal housings can be designed according to the location of the multiple metal housings on the thick-walled structure, the mechanical properties and heat transfer characteristics of the thick-walled structure, and the target temperature of the non-working surface of the multiple metal housings can be set respectively.
[0027] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description
[0028] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:
[0029] Figure 1 This is a side sectional view of a thermal stress protection device for thick-walled structures under variable temperature conditions according to an embodiment of the present invention;
[0030] Figure 2 The housing according to an embodiment of the present invention is in Figure 1 Sectional view at point AA;
[0031] Figure 3 This is a cross-sectional view of the limiting block and the heating element according to an embodiment of the present invention.
[0032] Figure Labels
[0033] Metal casing 10; outer shell 11; cooling medium inlet 12; cooling medium outlet 13; inner partition 14; fastening bolt 15; cooling assembly 20; fins 21; electric heating assembly 30; heating element 31; limiting block 32; filler 33; thermal pad 40; insulation layer 50; measurement system 60; flow meter 61; temperature sensor 62; data acquisition system 63; control system 70; regulating valve 71; control cabinet 72; power supply system 80; thick-walled structure 90; working surface 91; non-working surface 92. Detailed Implementation
[0034] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.
[0035] The following is combined Figures 1 to 3 This invention describes a thermal stress protection device for thick-walled structures operating under varying temperatures.
[0036] like Figure 1 and Figure 2As shown, the thermal stress protection device for thick-walled structures under variable temperature conditions according to an embodiment of the present invention includes a metal shell 10, an electric heating component 30, a cooling component 20, an insulation layer 50, a measurement system 60, a power supply system 80, and a control system 70. The metal casing 10 includes an outer shell 11 and an inner partition 14. The outer shell 11 covers the non-working surface 92 of the thick-walled structure 90, and the outer shell 11 is provided with a cooling medium inlet 12 and a cooling medium outlet 13. The inner partition 14 is disposed inside the outer shell 11, dividing the internal space of the outer shell 11 into an independent inner space and an outer space. The outer space is connected to the cooling medium inlet 12 and the cooling medium outlet 13. The electric heating assembly 30 is disposed in the inner space. The cooling assembly 20 includes an outer space and a cooling medium flowing through the outer space. The insulation layer 50 covers the outer surface of the metal casing 10. The measuring system 60 is used to measure the working surface temperature, non-working surface temperature and cooling medium flow rate of the thick-walled structure 90 in real time. The power supply system 80 is used to provide power to the electric heating assembly 30. The control system 70 controls the cooling medium flow rate or electric heating power according to the working surface temperature of the thick-walled structure 90, so that the non-working surface temperature of the thick-walled structure 90 reaches the target value.
[0037] Specifically, the metal casing 10 includes an outer shell 11 and an inner partition 14. The outer shell 11 covers the non-working surface 92 of the thick-walled structure 90, and the outer shell 11 is provided with a cooling medium inlet 12 and a cooling medium outlet 13. The inner partition 14 is disposed inside the outer shell 11, dividing the internal space of the outer shell 11 into independent inner and outer spaces, with the outer space communicating with the cooling medium inlet 12 and the cooling medium outlet 13. It is understood that the metal casing 10 has good thermal conductivity and high strength. The outer shell 11 covers the non-working surface 92 of the thick-walled structure 90, which is typically the outer surface of the thick-walled structure 90; that is, the outer shell 11 typically covers the outer surface of the thick-walled structure 90, and can be secured by fastening bolts 15 (such as...). Figure 2 (As shown) It is fixed on the outer surface of the thick-walled structure 90 for easy installation and disassembly. It can be used not only for new equipment but also for in-service equipment. The inner partition 14 is set inside the outer shell 11. The inner partition 14 can be welded to the shell and divided the internal space of the outer shell 11 into independent inner and outer spaces. The inner space is used to install the electric heating component 30, and the outer space serves as a channel for the flow of cooling working fluid.
[0038] The electric heating component 30 is disposed in the inner space, enabling the thermal stress protection device for the thick-walled structure under variable temperature conditions in this embodiment of the invention to have a heating function; when the working surface 91 of the thick-walled structure 90 heats up, the non-working surface 92 of the thick-walled structure 90 can be heated by the electric heating component 30 to adjust the internal temperature field of the thick-walled structure 90, reduce thermal stress, reduce fatigue damage, and extend the service life of the thick-walled structure 90.
[0039] The cooling assembly 20 includes an outer space and a cooling medium flowing through the outer space. The outer space is connected to the cooling medium inlet 12 and the cooling medium outlet 13, allowing the cooling medium to enter the outer space from the cooling medium inlet 12, flow through the outer space, and exit through the cooling medium outlet 13, forming a circulating flow. This enables the thermal stress protection device for thick-walled structures under variable temperature conditions in this embodiment to have a cooling function. When the working surface 91 of the thick-walled structure 90 cools down, the cooling assembly 20 can cool the surface of the thick-walled structure 90. Specifically, the cooling medium conducts heat through the inner partition 14, the non-operating electric heating assembly 30, and the outer shell 11 to cool the non-working surface 92 of the thick-walled structure 90, thereby regulating the internal temperature field of the thick-walled structure 90, reducing thermal stress, reducing fatigue damage, and extending the service life of the thick-walled structure 90. The cooling medium can be air, water, oil, or refrigerant, etc.
[0040] The insulation layer 50 covers the outer surface of the metal housing 10 to reduce heat loss. For example, when the working surface 91 of the thick-walled structure 90 is at a constant temperature, the electric heating component 30 and the cooling component 20 can be kept warm by the insulation layer 50.
[0041] The measurement system 60 is used to measure the working surface temperature, non-working surface temperature, and cooling fluid flow rate of the thick-walled structure 90 in real time; the power supply system 80 is used to provide power to the electric heating component 30; the control system 70 controls the cooling fluid flow rate or electric heating power according to the working surface temperature of the thick-walled structure 90, so that the non-working surface temperature of the thick-walled structure 90 can quickly and accurately reach the target value. By controlling the non-working surface temperature of the thick-walled structure 90, the temperature field of the thick-walled structure 90 is made more uniform, thereby reducing thermal stress, reducing fatigue damage, and extending the service life of the thick-walled structure 90.
[0042] The thermal stress protection device for thick-walled structures under variable temperature conditions according to embodiments of the present invention has the following advantages: First, since it simultaneously possesses heating and cooling functions, it can select active heating or active cooling based on the temperature change state of the working surface of the thick-walled structure 90, automatically adjusting the temperature of the non-working surface, resulting in a more uniform internal temperature field for the thick-walled structure 90, thereby reducing thermal stress, reducing fatigue damage, and extending the service life of the thick-walled structure 90; Second, based on the working surface temperature and its changing trend of the thick-walled structure 90, the temperature of the non-working surface can be automatically adjusted by the measurement system 60 and the control system 70 to quickly and accurately reach the target temperature, making it suitable for large-amplitude and rapid temperature change conditions, overcoming the shortcomings of current measures; Third, in addition to reducing the thermal stress of the thick-walled structure 90, it does not affect other functions and characteristics of the thick-walled structure 90; Fourth, the cooling component 20 and the electric heating component 30 are integrated in the same metal housing 10, resulting in a compact structure that facilitates transportation and installation.
[0043] In some embodiments, when the working surface 91 of the thick-walled structure 90 heats up, the cooling component 20 stops working, and the electric heating component 30 is activated to heat the surface of the thick-walled structure 90; when the working surface 91 of the thick-walled structure 90 cools down, the electric heating component 30 stops working, and the cooling component 20 is activated to cool the surface of the thick-walled structure 90; when the working surface temperature of the thick-walled structure 90 is constant, both the cooling component 20 and the electric heating component 30 stop working, and the insulation layer 50 keeps the thick-walled structure 90 warm. In other words, because the thermal stress protection device for variable-temperature conditions of the thick-walled structure in this embodiment of the invention has both heating and cooling functions, the appropriate function can be selected according to the temperature change trend of the thick-walled structure 90 to actively adjust the internal temperature field of the thick-walled structure 90 in real time, reduce thermal stress, reduce fatigue damage, and extend the service life of the thick-walled structure 90.
[0044] In some embodiments, the electric heating component 30 is made of a material with high thermal conductivity, so that the cooling component 20 can still rapidly cool the non-working surface 92 of the thick-walled structure 90 even though it is not in close contact with the thick-walled structure 90.
[0045] In some embodiments, such as Figure 1 and Figure 3 As shown, the electric heating assembly 30 includes a heating element 31, a limiting block 32, and a filler 33. The heating element 31 is fixed in the inner space by the limiting block 32, which is an insulating solid used for fixing and insulating the heating element 31. The heating element 31 is electrically connected to the power supply system 80. When the heating element 31 is energized, it can generate Joule heat. The filler 33 fills the remaining gaps in the inner space after the limiting block 32 and the heating element 31 are set, enhancing heat conduction. It can be understood that the heating element 31 generates heat through the power supply system 80. The generated heat can be exchanged with the non-working surface 92 of the thick-walled structure 90 through the limiting block 32 and the filler 33, raising the temperature of the non-working surface 92 of the thick-walled structure 90, thereby regulating the internal temperature field of the thick-walled structure 90, reducing thermal stress, reducing fatigue damage, and extending the service life of the thick-walled structure 90. The heating element 31 is fixed by the limiting block 32 and the filler 33 at the same time, so the heating element 31 will not be deformed. At the same time, the limiting block 32 and the filler 33 are required to have good insulation, so the heating element 31 will not come into contact with the metal shell 10 and cause a short circuit.
[0046] In some embodiments, there are multiple limiting blocks 32, which are fixed in the inner space at intervals along the axial direction of the thick-walled structure 90. Each of the multiple limiting blocks 32 is provided with a through hole, through which the heating element 31 is fixed. The heating element 31 is reliably fixed and will not directly contact the metal housing 10, making it safe to use.
[0047] In some embodiments, the heating element 31 is sheet-shaped, which results in a large heating area, uniform heating, low heat flux density, high mechanical strength, and long service life.
[0048] In some embodiments, the heating element 31 is a thin sheet made of high-temperature resistant metal or graphite, which can generate Joule heat when energized. The thickness and shape of the heating element 31 can be selected according to the heating power and the power supply voltage.
[0049] In some embodiments, the limiting block 32 is made of corundum, which has high mechanical strength, firm positioning, good insulation, and low thermal resistance.
[0050] In some embodiments, the filler 33 is a material such as magnesium oxide or boron nitride, which has a high thermal conductivity and can reduce the thermal resistance between the heating element 31 and the metal casing 10.
[0051] In some embodiments, such as Figure 1 As shown, the cooling assembly 20 also includes multiple fins 21, which are fixed to the inner partition 14 at intervals. By providing multiple fins 21, heat exchange can be enhanced. The fins 21 can be made of metal materials with high thermal conductivity, such as aluminum or copper, and are welded and fixed to the inner partition 14.
[0052] In some embodiments, such as Figure 1As shown, the measurement system 60 includes a flow meter 61, a temperature sensor 62, and a data acquisition system 63. The flow meter 61 is installed on the upstream pipe of the cooling medium inlet 12 to measure the flow rate of the cooling medium entering the outer space. The temperature sensor 62 is distributed at the working surface 91 and non-working surface 92 of the thick-walled structure 90 to measure the temperature at these locations in real time. The data acquisition system 63 collects data from the flow meter 61 and the temperature sensor 62. The control system 70 includes a control cabinet 72 and a regulating valve 71. The control cabinet 72 is communicatively connected to the data acquisition system 63. Specifically, the data acquisition system 63 can communicate via CAN, RS232, and RS432. The system 85 communicates with the control cabinet 72 via any interface such as CAN, RS232, RS485, or LAN to receive data from the flow meter 61 and temperature sensor 62 transmitted by the data acquisition system 63 in real time. The regulating valve 71 is also connected to the control cabinet 72 to provide feedback and adjust the valve opening between the cooling medium inlet 12 and the flow meter 61. Specifically, the regulating valve 71 is either pneumatic or electric and can communicate with the control cabinet 72 via any interface such as CAN, RS232, RS485, or LAN. The power supply system 80 communicates with the control cabinet 72; specifically, it can be an AC or DC power supply equipped with a silicon controlled rectifier (SCR) voltage regulator and communicates with the control cabinet 72 via any interface such as CAN, RS232, RS485, or LAN. This allows for real-time and proactive adjustment of the internal temperature field of the thick-walled structure 90, reducing thermal stress, minimizing fatigue damage, and extending its service life.
[0053] It should be noted that the flow meter 61 can be an orifice plate type, vortex type, electromagnetic type or other types of flow meter 61, and is installed on the upstream pipe of the cooling working medium inlet 12, with straight pipe sections of at least 10 times and 5 times the pipe diameter respectively before and after; the temperature sensor 62 can be a thermocouple or a resistance temperature detector, and is tightly fixed on the working surface 91 and non-working surface 92 of the thick-walled structure 90.
[0054] In some embodiments, such as Figure 1 and Figure 2 As shown, it also includes a thermal pad 40, which is laid between the outer shell 11 and the thick-walled structure 90 to reduce contact thermal resistance.
[0055] In some embodiments, the thermal pad 40 is graphite, metal foam, metal foil, or thermally conductive silicone, all of which are materials with high thermal conductivity.
[0056] It should be noted that the cooling component 20 uses fins 21 to enhance heat exchange, the limiting block 32 is made of corundum, the filler 33 is magnesium oxide and boron nitride, and the thermal pad 40 reduces contact thermal resistance. Based on these measures, the thermal stress protection device for thick-walled structures under variable temperature conditions in this embodiment of the invention has high heat transfer efficiency.
[0057] In some embodiments, the insulation layer 50 is made of a high-temperature resistant insulation material, which may be an aerosol, a zirconium fiber blanket, an aluminum silicate cotton needled blanket, or other high-temperature resistant insulation materials.
[0058] In some embodiments, there are multiple metal housings 10, forming a combined metal housing 10. The structural dimensions of each metal housing 10, the cooling power of the corresponding cooling components 20, and the heating power of the heating components within each metal housing 10 can be designed based on their location on the thick-walled structure 90, the mechanical properties of the thick-walled structure 90, and its heat transfer characteristics. Target temperatures are also set for the non-working surfaces 92 of each metal housing 10. This combined metal housing 10-based thermal stress protection device for thick-walled structures under variable temperature conditions is suitable for thermal stress protection in complex structures and complex heat transfer processes. It should be noted that the metal housing 10 can also be a single metal housing 10.
[0059] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0060] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.
Claims
1. A thermal stress protection device for thick-walled structures under variable temperature conditions, characterized in that, include: A metal housing, the metal housing comprising an outer shell and an inner partition; The outer shell covers the non-working surface of the thick-walled structure, and the outer shell is provided with a cooling medium inlet and a cooling medium outlet; the inner partition is disposed inside the outer shell, dividing the internal space of the outer shell into an independent inner space and an outer space, and the outer space is connected to the cooling medium inlet and the cooling medium outlet; An electric heating assembly is disposed in the inner space; A cooling assembly, the cooling assembly including the outer space and a cooling medium flowing through the outer space; A heat insulation layer, which covers the outer surface of the metal casing; The measurement system is used to measure the working surface temperature, non-working surface temperature, and cooling fluid flow rate of the thick-walled structure in real time. A power supply system is used to provide power to the electric heating assembly; The control system controls the flow rate of the cooling medium or the electric heating power according to the working surface temperature of the thick-walled structure, so that the non-working surface temperature of the thick-walled structure reaches the target value. The electric heating assembly includes a heating element, a limiting block, and a filler. The heating element is fixed in the inner space by the limiting block. The heating element is electrically connected to the power supply system. The filler fills the remaining gap in the inner space after the limiting block and the heating element are set. The heating element is sheet-shaped; the heating element does not contact the metal shell; heat exchange occurs between the heating element and the non-working surface of the thick-walled structure through the filler and the limiting block.
2. The thermal stress protection device for thick-walled structures under variable temperature conditions according to claim 1, characterized in that, When the working surface of the thick-walled structure heats up, the cooling component stops working and the electric heating component is activated to heat the surface of the thick-walled structure; when the working surface of the thick-walled structure cools down, the electric heating component stops working and the cooling component is activated to cool the surface of the thick-walled structure; when the temperature of the working surface of the thick-walled structure is constant, both the cooling component and the electric heating component stop working, and the insulation layer keeps the thick-walled structure warm.
3. The thermal stress protection device for thick-walled structures under variable temperature conditions according to claim 1, characterized in that, The electric heating component is made of a material with high thermal conductivity.
4. The thermal stress protection device for thick-walled structures under variable temperature conditions according to claim 1, characterized in that, There are multiple limiting blocks, which are fixed in the inner space at intervals along the axial direction of the thick-walled structure. Each of the multiple limiting blocks is provided with a through hole, through which the heating element is fixed.
5. The thermal stress protection device for thick-walled structures under variable temperature conditions according to claim 1, characterized in that, The heating element is a thin sheet made of high-temperature resistant metal or graphite.
6. The thermal stress protection device for thick-walled structures under variable temperature conditions according to claim 1, characterized in that, The limiting block is made of corundum.
7. The thermal stress protection device for thick-walled structures under variable temperature conditions according to claim 1, characterized in that, The filler is magnesium oxide and boron nitride.
8. The thermal stress protection device for thick-walled structures under variable temperature conditions according to any one of claims 1-7, characterized in that, The cooling assembly also includes a plurality of fins, which are fixed at intervals to the inner partition.
9. The thermal stress protection device for thick-walled structures under variable temperature conditions according to any one of claims 1-7, characterized in that, The measurement system includes a flow meter, a temperature sensor, and a data acquisition system. The flow meter is installed on the upstream pipe of the cooling medium inlet to measure the flow rate of the cooling medium entering the outer space. The temperature sensor is distributed at the working and non-working surfaces of the thick-walled structure to measure the temperature at these surfaces in real time. The data acquisition system collects data from the flow meter and the temperature sensor. The control system includes a control cabinet and a regulating valve. The control cabinet is communicatively connected to the data acquisition system to receive data from the flow meter and the temperature sensor transmitted by the data acquisition system in real time. The regulating valve is communicatively connected to the control cabinet to provide feedback and adjust the valve opening located between the cooling medium inlet and the flow meter. The power supply system is equipped with a thyristor voltage regulator and communicates with the control cabinet, allowing for automatic adjustment of the output voltage by a program.
10. The thermal stress protection device for thick-walled structures under variable temperature conditions according to any one of claims 1-7, characterized in that, It also includes a thermal pad, which is laid between the outer shell and the thick-walled structure.
11. The thermal stress protection device for thick-walled structures under variable temperature conditions according to any one of claims 1-7, characterized in that, The insulation layer is made of high-temperature resistant heat insulation material.
12. The thermal stress protection device for thick-walled structures under variable temperature conditions according to any one of claims 1-7, characterized in that, The metal housings are multiple, and the multiple metal housings form a combined metal housing. The structural dimensions of the multiple metal housings, the cooling power of the corresponding cooling components and the heating power of the heating components in the multiple metal housings are designed according to the location of the multiple metal housings on the thick-walled structure, the mechanical properties and heat transfer characteristics of the thick-walled structure, and the target temperature of the non-working surface of the multiple metal housings is set respectively.