Experimental device and method for testing insulation performance of nuclear release heat electric heating simulation rod

Abstract

The invention discloses an experimental device and method for testing the insulation performance of a nuclear release heat electric heating simulation rod, and the experimental device comprises a testing assembly, a cooling assembly, and a data collection module. At least one heating rod to be tested is arranged in the test assembly; the test assembly supplies power to the positive pole point of the to-be-tested heating rod in the test assembly, and supplies power to the to-be-tested heating rod to the rated power of the to-be-tested heating rod; the cooling assembly cools the to-be-tested heating rod and the positive and negative electrode insulating layer points. Therefore, before the design of the electric heating reactor core of the reactor, the insulation performance experiment test can be carried out on the to-be-tested heating rod and the minimum unit which form the electric heating simulation reactor core, the insulation failure boundary of the to-be-tested heating rod in the experiment is explored, the experiment support is provided for the electric heating simulation reactor core power connection design in the reactor thermal hydraulic experiment, and the test efficiency is improved. Therefore, the safety of the reactor thermal hydraulic experiment is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nuclear heat release electric heating simulation rod performance test, and particularly relates to a nuclear heat release electric heating simulation rod insulation performance test device and method. BACKGROUND

[0002] Safety is always the first priority in nuclear energy development. Advanced pressurized water reactors have become the mainstream trend of nuclear energy development due to their multiple uses, safety and reliability. New reactor type research and development design should be supported and verified by corresponding thermal hydraulic experiments to ensure the safety and reliability of the design. In the reactor thermal hydraulic experiment, the reactor nuclear fuel rod is mostly simulated by nuclear heat release electric heating rods to reflect the power distribution and heat transfer characteristics of the real reactor core.

[0003] As a key equipment in the reactor thermal hydraulic experiment, the electric heating rod is very expensive. During the high temperature and high pressure thermal experiment, the electric heating rod has a large power load, and the high temperature at the positive and negative electrodes of the electric heating rod may cause insulation failure of a single heating rod, which may cause regional ionization between the failed heating rod and the surrounding heating rods, damage the electric heating core, cause huge economic losses, and seriously affect the experiment. The effectiveness of the insulation of the heating rod is the first barrier to the safety of the electric core, so before designing the electric heating core of the reactor, the insulation performance of the electric heating rod and the minimum unit of the electric heating simulation core should be tested to explore the insulation failure boundary of the electric heating rod under the experiment, and to provide experimental support for the electric heating simulation core of the reactor thermal hydraulic experiment, so as to ensure the safety of the reactor thermal hydraulic experiment. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a nuclear heat release electric heating simulation rod insulation performance test device and method.

[0005] The technical scheme adopted by the present application to solve its technical problems is: a nuclear heat release electric heating simulation rod insulation performance test experimental device is constructed, comprising: a test assembly, a cooling assembly and a data acquisition module; at least one to-be-tested heating rod is arranged in the test assembly; the test assembly supplies power to the positive pole point of the to-be-tested heating rod located therein, and supplies power to the to-be-tested heating rod to its rated power; the cooling assembly cools and lowers the temperature of the to-be-tested heating rod and the positive and negative pole insulation layer points; the data acquisition module records the temperature of the to-be-tested heating rod, the temperature of the negative pole point, the positive and negative pole insulation layer points, the positive pole point of the to-be-tested heating rod, the voltage and current provided by the test assembly, and the cooling speed and temperature of the positive and negative pole insulation layer points of the to-be-tested heating rod by the cooling assembly; the cooling capacity of the cooling assembly on the positive and negative pole insulation layer points of the to-be-tested heating rod is reduced, the temperature of the positive and negative pole insulation layer points of the to-be-tested heating rod gradually increases until breakdown, and the data acquisition module acquires the cooling temperature change in the breakdown process of the positive and negative pole insulation layer points of the to-be-tested heating rod.

[0006] Further, the test assembly comprises: a direct current power supply, a safety device, a fixing device and a container in communication with the cooling assembly, the fixing device fixes the to-be-tested heating rod in the container, the direct current power supply is in electrical communication with the positive pole point of the to-be-tested heating rod through the safety device, and the positive and negative pole insulation layer points of the to-be-tested heating rod are exposed outside the container; Further, the fixing device comprises a plurality of positioning grids arranged at different heights in the container, and a positioning flange for sealing the end of the container and limiting the to-be-tested heating rod, the positioning flange is provided with a through hole allowing the to-be-tested heating rod to pass through, the positioning flange is in electrical communication with the negative pole point of the to-be-tested heating rod, and the positioning flange is provided with a wiring end in electrical communication with the negative pole grounding end.

[0007] Further, the container is a cylindrical cylinder, the bottom of the container is provided with a cooling water inlet in communication with the cooling assembly, the upper side of the container is provided with a cooling water outlet, the cooling assembly makes the cooling water in the container circulate, the top of the container is provided with a flange sealing surface connected with the positioning flange; the inner diameter of the cylindrical cylinder is consistent with the inner diameter of the channel in the electric heating core.

[0008] Further, the test assembly further comprises a liquid level meter and a pressure gauge arranged on the container, and temperature measuring thermocouples arranged at different heights of the container, for real-time monitoring of the temperature inside the container at different liquid levels and the temperature of the positive and negative pole insulation layer points of the to-be-tested heating rod.

[0009] Further, the cooling assembly comprises a circulating cooling loop for cooling the lower part of the heating rod to be tested and a cooling element for point cooling of the positive and negative electrode insulation layer of the heating rod to be tested; the circulating cooling loop is in communication with the inside of the container, and the cooling element is air cooling or water cooling.

[0010] Further, the circulating cooling loop comprises a pipeline, and an oxygen removal water tank, a circulating cooling pump, an inlet valve, a drain valve, an outlet valve, a condenser, an inlet flow meter and a temperature and pressure measuring instrument arranged on the pipeline; the cooling water inlet is in communication with the pipeline between the inlet valve and the drain valve, and the cooling water outlet is in communication with the pipeline between the drain valve and the outlet valve.

[0011] Further, the data acquisition module comprises a central control module and a camera; the central control module is electrically connected with the oxygen removal water tank, the circulating cooling pump, the inlet valve, the drain valve, the outlet valve, the condenser, the inlet flow meter, the temperature and pressure measuring instrument, the camera, the liquid level meter, the temperature measuring thermocouple and the pressure gauge; the camera acquires the changes of the positive and negative electrode insulation layer points of the heating rod to be tested during the experiment.

[0012] The application further provides a method for testing the insulation performance of a nuclear heat release electric heating simulation rod, comprising the following steps: S1, placing at least one heating rod to be tested into a test assembly and a cooling assembly; S2, supplying power to the positive electrode point of the heating rod to be tested located in the test assembly; S3, supplying power to the heating rod to be tested by the test assembly to keep the rated power unchanged, and reducing the cooling capacity of the cooling assembly to the heating rod to be tested and the positive and negative electrode insulation layer points; S4, continuously increasing the temperature of the heating rod to be tested and the positive and negative electrode insulation layer points, and observing the resistance changes of the heating rod to be tested and the live pictures of the positive and negative electrode insulation layer points in real time; when the positive and negative electrode insulation layer points of the heating rod to be tested appear mutation and short-circuit insulation failure occurs, recording the temperature changes of the positive and negative electrode insulation layer points of the heating rod to be tested at this time.

[0013] Further, the step S1 specifically comprises the following steps: S11, connecting the positive and negative electrode insulation layer points of the heating rod to be tested with the cooling element; S12, sealing the lower part of the heating rod to be tested and placing it into the circulating cooling loop; and S13, calculating the flow of the circulating cooling liquid in the circulating cooling loop through the rated power of the heating rod to be tested.

[0014] Further, the step S2 specifically comprises the following steps: S21, electrically connecting the direct current power supply with the safety device; S22, electrically connecting the safety device with the positive electrode point of the heating rod to be tested; and S23, electrically connecting the negative electrode point of the heating rod to be tested with the positioning flange, and then electrically connecting the negative electrode point with the grounding end through the wiring end.

[0015] Further, the step S3 specifically comprises: S31, simultaneously starting the circulating cooling circuit and the cooling member; S32, gradually increasing the output power of the direct current power supply to the heating rod under test until reaching the rated power of the heating rod under test, keeping the rated power unchanged; S33, keeping the flow of the circulating cooling circuit unchanged, and then reducing the cooling capacity of the cooling member to the positive and negative electrode insulation layer points of the heating rod under test, so that the temperature at the positive and negative electrode insulation layer points of the heating rod under test continuously increases.

[0016] Further, the step S4 specifically comprises: S41, the temperature of the positive and negative electrode insulation layer points of the heating rod under test gradually increases, and the resistance change of the heating rod under test and the monitoring picture are observed in real time; when the resistance of the heating rod under test and the positive and negative electrode insulation layer points appear mutation, insulation failure occurs, and the temperature of the positive and negative electrode insulation layer points of the heating rod under test at this time is recorded, that is, the temperature boundary value of the insulation failure of the heating rod under test; S42, when the insulation failure of the heating rod under test occurs, the circulating cooling circuit and the cooling member are closed.

[0017] The implementation of the present application has the following beneficial effects: The present application supplies power to the positive electrode point of the heating rod under test in the test assembly, keeps the power supplied by the test assembly to the heating rod under test unchanged, then reduces the cooling capacity of the cooling assembly to the positive and negative electrode insulation layer points of the heating rod under test, the temperature at the positive and negative electrode insulation layer points of the heating rod under test gradually increases, until the heating rod under test is observed to be broken down by the current provided by the test assembly, insulation failure of the heating rod under test occurs, and air ionization phenomenon occurs, the temperature of the heating rod under test, the temperature of the positive and negative electrode insulation layer points of the heating rod under test, the voltage and current provided by the test assembly, and the cooling speed and temperature of the cooling assembly to the positive and negative electrode insulation layer points of the heating rod under test are recorded by the data acquisition module, and then the boundary of the insulation failure of the heating rod under test under the key parameters of voltage, current, and temperature of the positive and negative electrode insulation layer points of the heating rod under test is obtained, the insulation failure criterion under the synergistic action of multiple factors is established, and is used to guide the voltage and current distribution and cooling design of the electric heating core. Further, before the design of the reactor electric heating core, the insulation performance experiment test of the heating rod under test and the minimum unit constituting the electric heating simulation core is carried out, the insulation failure boundary of the heating rod under test under the experiment is explored, experimental support is provided for the electric heating simulation core power connection design in the reactor thermal hydraulic experiment, so as to ensure the safety of the reactor thermal hydraulic experiment. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the present application, the present application will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0019] In the drawings: Figure 1 is a structural schematic diagram of a nuclear heat release electric heating simulation rod insulation performance test experimental device in some embodiments of the present application; Figure 2 is a structural schematic diagram of a circulating cooling loop in some embodiments of the present application; Figure 3 is a structural schematic diagram of a container and a fixing part in some embodiments of the present application; Figure 4 is a cross-sectional schematic diagram of a container and a fixing part in some embodiments of the present application; Figure 5 is a flow schematic diagram of a nuclear heat release electric heating simulation rod insulation performance test experimental method in some embodiments of the present application; Figure 6 is a flow schematic diagram of step S3 of a nuclear heat release electric heating simulation rod insulation performance test experimental method in some embodiments of the present application.

[0020] Legend to the Figures DC power supply 1, safety device 2, test assembly 3, fixing part 31, positioning grid 311, positioning flange 312, wiring end 313, container 32, cooling water inlet 33, cooling water outlet 34, flange sealing surface 35, liquid level meter 36, pressure gauge 37, temperature measuring thermocouple 38, cooling assembly 4, circulating cooling loop 41, pipeline 411, deoxygenated water tank 412, circulating cooling pump 413, inlet valve 414, drainage valve 415, outlet valve 416, condenser 417, inlet flow meter 418, temperature and pressure measuring instrument 419, cooling part 42, data acquisition module 5, central control module 51, camera 52, to-be-tested heating rod 6. DETAILED DESCRIPTION

[0021] In order to make the technical features, objectives and effects of the present application clearer, the specific embodiments of the present application will be described in detail with reference to the drawings. In the following description, it should be understood that the "front", "back", "upper", "lower", "left", "right", "vertical", "horizontal", "vertical", "horizontal", "top", "bottom", "inner", "outer", "head", "tail" and other indications of orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, constructed and operated in a particular orientation, and are only for the convenience of describing the technical solutions, and do not indicate that the devices or elements referred to must have a particular orientation, therefore, it cannot be understood as a limitation on the present application.

[0022] It should also be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing", "setting" and the like should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements or the interaction relationship between two elements. When an element is referred to as "on" or "under" another element, the element can be "directly" or "indirectly" located on the other element, or there can be one or more intervening elements. The terms "first", "second", "third" and the like are only for the convenience of describing the technical solutions, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features, therefore, the features with "first", "second", "third" and the like can be explicitly or implicitly included one or more of the features. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0023] In the following description, specific details such as specific system structures, techniques, etc. are presented for the purpose of illustration, not for the purpose of limitation, so as to make a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed description of well-known systems, devices, circuits and methods is omitted to avoid unnecessary details that hinder the description of the present application.

[0024] Please refer to Figures 1 to 4The nuclear heat release electric heating simulation rod insulation performance test experimental device in the first embodiment of the present application comprises: a test assembly 3, a cooling assembly 4 and a data acquisition module 5, at least one to-be-tested heating rod 6 is arranged in the test assembly 3, the test assembly 3 supplies power to the positive pole point of the to-be-tested heating rod 6 located therein, the to-be-tested heating rod 6 is supplied with power to its rated power, the cooling assembly 4 cools and lowers the temperature of the to-be-tested heating rod 6 and the positive and negative pole insulation layer points, the data acquisition module 5 records the temperature of the to-be-tested heating rod 6, the negative pole point of the to-be-tested heating rod 6, the positive and negative pole insulation layer points, the temperature of the positive pole point, the voltage and current provided by the test assembly 3 and the cooling speed and temperature of the cooling assembly 4 on the positive and negative pole insulation layer points of the to-be-tested heating rod 6, the cooling capacity of the cooling assembly 4 on the positive and negative pole insulation layer points of the to-be-tested heating rod 6 is reduced, the temperature of the positive and negative pole insulation layer points of the to-be-tested heating rod 6 gradually increases until breakdown, and the data acquisition module 5 acquires the cooling temperature change in the breakdown process of the positive and negative pole insulation layer points of the to-be-tested heating rod 6.

[0025] The present application supplies power to the positive pole point of the to-be-tested heating rod 6 located in the test assembly 3, the to-be-tested heating rod 6 is supplied with power to its rated power by the test assembly 3, then the cooling capacity of the cooling assembly 4 on the to-be-tested heating rod 6 and the positive and negative pole insulation layer points is gradually reduced, the temperature at the positive and negative pole insulation layer points of the to-be-tested heating rod 6 gradually increases until the to-be-tested heating rod 6 is observed to be broken down by the current provided by the test assembly 3, insulation failure of the to-be-tested heating rod 6 occurs, and air ionization phenomenon occurs, the temperature of the to-be-tested heating rod 6, the negative pole point of the to-be-tested heating rod 6, the positive and negative pole insulation layer points, the temperature of the positive pole point, the voltage and current provided by the test assembly 3 and the cooling speed and temperature of the cooling assembly 4 on the positive and negative pole insulation layer points of the to-be-tested heating rod 6 are recorded by the data acquisition module 5, the data acquisition module 5 also acquires the cooling temperature change in the breakdown process of the positive and negative pole insulation layer points of the to-be-tested heating rod 6, and the boundary of insulation failure of the to-be-tested heating rod 6 under the key parameters of voltage, current and temperature of the positive and negative pole insulation layer points of the to-be-tested heating rod 6 is obtained, the insulation failure criterion under the synergistic action of multiple factors is established, and is used for guiding the voltage and current distribution and cooling design of the electric heating core. Further, the insulation performance experimental test of the to-be-tested heating rod 6 and the minimum unit constituting the electric heating simulation core can be performed before the electric heating core of the reactor is designed, the insulation failure boundary of the to-be-tested heating rod 6 in the experiment is explored, experimental support is provided for the electric heating simulation core connection design in the reactor thermal hydraulic experiment, the safety of the reactor thermal hydraulic experiment is ensured, the to-be-tested heating rod 6 is put into the test assembly 3, the entire experimental device is economical and simple, safe and reliable, has small operating pressure and low sealing requirement. The device is more compact as a whole, has low space requirement, representative core minimum unit arrangement is selected, the experimental power is small, the cooling assembly 4 and the data acquisition module 5 matched with the device have low requirement, and cost is saved.

[0026] The nuclear exothermic electric heating simulation rod insulation performance test experimental device can test the insulation performance of different to-be-tested heating rods 6 and different core arrangements, and only needs to replace the test assembly 3 or different to-be-tested heating rod 6 test bodies to perform the test, has a wide application range, and is simple and convenient to operate.

[0027] The to-be-tested heating rods 6 can be arranged in the test assembly 3 according to the arrangement mode and arrangement spacing of an actual thermal hydraulic experiment, so as to test the insulation performance of the to-be-tested heating rod 6 under the temperature, voltage, current and other factors of a single to-be-tested heating rod 6 and multiple to-be-tested heating rods 6. The test data can be closer to the actual use, the accuracy of the test data is further improved, and the safety is improved.

[0028] Please refer to Figures 1 to 4 In some embodiments, the test assembly 3 includes a direct current power supply 1, a safety device 2, a fixing device 31 and a container 32 in communication with the cooling assembly 4, the fixing device 31 fixes the to-be-tested heating rod 6 in the container 32, the direct current power supply 1 is in electrical communication with the positive electrode point of the to-be-tested heating rod 6 through the safety device 2, and the positive and negative electrode insulation layer points of the to-be-tested heating rod 6 are exposed outside the container 32.

[0029] The to-be-tested heating rod 6 is fixed in the container 32 by the fixing device 31, the direct current power supply 1 is in electrical communication with the positive electrode point of the to-be-tested heating rod 6 through the safety device 2, and the positive and negative electrode insulation layer points of the to-be-tested heating rod 6 are exposed outside the container 32. The safety device 2 can avoid damage to the to-be-tested heating rod 6 when the direct current power supply 1 suddenly changes, thereby improving the stability of the test experiment, and also plays a certain safety role, thereby reducing the cost of the test experiment. The safety device 2 can be an air safety device, which can be used in a circulating manner and is convenient for debugging, or the safety device 2 is a fuse, which automatically disconnects when the voltage or temperature is too high, thereby playing a certain protection role for the entire nuclear exothermic electric heating simulation rod insulation performance test experimental device and improving the safety.

[0030] Please refer to Figures 1 to 4 In some embodiments, the fixing device 31 includes multiple positioning grids 311 arranged at different heights inside the container 32, and a positioning flange 312 for sealing the end of the container 32 and limiting the to-be-tested heating rod 6. The positioning flange 312 is provided with a through hole allowing the to-be-tested heating rod 6 to pass through, the positioning flange 312 is in electrical communication with the negative electrode point of the to-be-tested heating rod 6, and the positioning flange 312 is provided with a wiring end 313 in electrical communication with the negative electrode grounding end.

[0031] The application comprises multiple positioning grids 311 arranged at different heights inside the container 32, and a positioning flange 312 for sealing the end of the container 32 and limiting the position of the heating rod 6 to be tested, wherein the positioning flange 312 is provided with a through hole allowing the heating rod 6 to be tested to pass through, and the multiple positioning grids 311 can be used to stably fix the single or multiple heating rods 6 to be tested in the container 32, and then the upper part of the heating rod 6 to be tested passes through the through hole of the positioning flange 312, the positioning flange 312 covers the end of the container 32, and the end of the container 32 is sealed, and the positioning flange 312 can fix the upper part of the heating rod 6 to be tested by cooperating with the through hole, thereby improving the stability of the heating rod 6 to be tested in the container 32, and improving the accuracy of the test experimental data, and the installation is more simple and convenient, the overall structure is more simple and durable, and the manufacturing cost is saved.

[0032] The application is electrically connected to the negative point of the heating rod 6 to be tested through the positioning flange 312, the positioning flange 312 is provided with a wiring end 313 in electrical communication with the negative ground end, and after the positioning flange 312 is connected to the negative point of the outer wall surface of the heating rod 6 to be tested, the wiring end 313 on the outer side of the positioning flange 312 is connected to the copper braid and then connected to the negative ground end, so that the negative point of the heating rod 6 to be tested passes through the positioning flange 312 and reaches the negative ground end, and the negative point of the outer wall surface of the heating rod 6 to be tested is in communication with the positioning flange 312, thereby reducing the wiring process, making the installation more convenient and labor-saving, improving the installation efficiency, reducing the risk of wire winding, and improving the safety.

[0033] Please refer to Figures 1 to 4 In some embodiments, the container 32 is a cylindrical body, the bottom of the container 32 is provided with a cooling water inlet 33 in communication with the cooling assembly 4, the upper side of the container 32 is provided with a cooling water outlet 34, the cooling assembly 4 is used to make the cooling water in the container 32 circulate, the top of the container 32 is provided with a flange sealing surface 35 connected to the positioning flange 312, and the inner diameter of the cylindrical body is consistent with the inner diameter of the channel in the electric heating core.

[0034] The application uses the cylindrical body of the container 32 to have the ability to bear greater pressure and is not easy to deform, thereby prolonging the service life and improving the safety, and the heating rod 6 to be tested can be reasonably arranged in the container 32.

[0035] The bottom of the container 32 is provided with a cooling water inlet 33 communicated with the cooling assembly 4, the upper side of the container 32 is provided with a cooling water outlet 34, the internal cooling water of the container 32 is circulated by the cooling assembly 4, and the top of the container 32 is provided with a flange sealing surface 35 connected with the positioning flange 312. The cooling water inlet 33 arranged at the bottom and the cooling water outlet 34 arranged at the upper part can reduce the flow of the cooling liquid after the cooling liquid provided by the cooling assembly 4 enters the container 32, so that the cooling liquid can be more fully contacted with the heating rod 6 to be tested inside the container 32, thereby making each cycle of the cooling liquid can take away a large amount of temperature inside the container 32, reducing the number of cycles and the speed of circulation, thereby reducing the use of energy and saving the cost of test experiment. The flange sealing surface 35 connected with the positioning flange 312 arranged at the top of the container 32 can improve the sealing between the container 32 and the positioning flange 312, and after installation, it can be more tightly, thereby improving the cooling effect of the cooling assembly 4 on the inside of the container 32.

[0036] The internal diameter of the cylindrical barrel body is consistent with the inner diameter of the channel in the electric heating core, so that the test experiment can be more close to the actual use, and the accuracy of the test experiment data is further improved, thereby improving the safety.

[0037] Please refer to Figures 1 to 4 In some embodiments, the test assembly 3 further comprises a liquid level meter 36 and a pressure gauge 37 arranged on the container 32, and a temperature measuring thermocouple 38 arranged at different heights of the container 32, for real-time monitoring of the temperature inside the container 32 at different liquid levels and the temperature of the positive and negative electrode insulation layer points of the heating rod 6 to be tested.

[0038] The liquid level meter 36 and the pressure gauge 37 arranged on the container 32 and the temperature measuring thermocouple 38 arranged at different heights of the container 32 are used to monitor the temperature inside the container 32 at different liquid levels and the temperature of the positive and negative electrode insulation points of the heating rod 6 in real time. The liquid level meter 36 and the pressure gauge 37 can better observe the position of the cooling liquid inside the container 32 and the pressure inside the container 32, thereby improving safety, facilitating debugging of the cooling assembly 4, making the heating rod 6 to be tested closer to the actual use state, thereby improving the accuracy and safety of the test experimental data. The temperature measuring thermocouple 38 can more intuitively observe the temperature inside the container 32 at different liquid levels, further debug the cooling assembly 4, improve the accuracy of the test experimental data, and also can monitor the temperature of the positive and negative electrode insulation points of the heating rod 6 to be tested in real time, thereby improving safety and recording the temperature change curve of the positive and negative electrode insulation points of the heating rod 6 to be tested when the insulation fails during the measurement experiment, which is used to explore the insulation failure boundary of the heating rod 6 to be tested under this experiment, and provides experimental support for the electric heating simulation reactor core power-on design in the reactor thermal-hydraulic experiment, so as to ensure the safety of the reactor thermal-hydraulic experiment.

[0039] Please refer to Figures 1 to 4 In some embodiments, the cooling assembly 4 includes a circulating cooling circuit 41 for cooling the lower part of the heating rod 6 to be tested and a cooling member 42 for cooling the positive and negative electrode insulation points of the heating rod 6 to be tested. The circulating cooling circuit 41 is in communication with the inside of the container 32, and the cooling member 42 is air-cooled or water-cooled.

[0040] The circulating cooling circuit 41 and the cooling member 42 are used to circulate the cooling liquid into the container 32 through the circulating cooling circuit 41 in communication with the cooling water inlet 33 and the cooling water outlet 34 of the container 32, thereby achieving the effect of cooling the lower part of the heating rod 6 to be tested. The temperature of the positive and negative electrode insulation points of the heating rod 6 to be tested is changed by the air-cooled or water-cooled cooling member 42, so that the temperature of the positive and negative electrode insulation points of the heating rod 6 to be tested gradually increases until the positive and negative electrode insulation points of the heating rod 6 to be tested are broken down by the current provided by the direct current power supply 1, the heating rod 6 to be tested fails, and the boundary temperature of the heating rod 6 to be tested when the insulation fails is obtained. The operation is simple and convenient, and the accuracy of the test experimental data is improved.

[0041] When the cooling element 42 is air-cooled, the shell of the cooling element 42 covers the upper part of the heating rod 6 to be tested, but exposes the positive and negative electrode insulation points of the heating rod 6 to be tested. A plurality of openings are arranged on the shell and face the positive and negative electrode insulation points of the heating rod 6 to be tested. When the fan of the cooling element 42 blows cold air in the shell, the cold air flows out from the openings and acts on the positive and negative electrode insulation points of the heating rod 6 to be tested, causing convective heat exchange at the positive and negative electrode insulation points of the heating rod 6 to be tested, reducing heat backflow, and achieving better heat dissipation effect. In addition, the number of fans can be reduced, energy can be saved, the cost of the test experiment can be reduced, and the temperature at the positive and negative electrode insulation points of the heating rod 6 to be tested can be changed more flexibly and conveniently.

[0042] When the cooling element 42 is water-cooled, the circulating pipeline of the water cooling is wound around the positive and negative electrode insulation points of the heating rod 6 to be tested. The heat at the positive and negative electrode insulation points of the heating rod 6 to be tested is taken away by the circulation of water, thereby achieving the effect of cooling the positive and negative electrode insulation points of the heating rod 6 to be tested. The temperature change of the positive and negative electrode insulation points of the heating rod 6 to be tested can be controlled by controlling the speed of water circulation, thereby being more convenient to operate. The water-cooled cooling element 42 has better cooling effect and can be recycled to save energy.

[0043] Please refer to Figures 1 to 4 In some embodiments, the circulating cooling circuit 41 comprises a pipeline 411, and a deoxygenated water tank 412, a circulating cooling pump 413, an inlet valve 414, a drain valve 415, an outlet valve 416, a condenser 417, an inlet flow meter 418, and a temperature and pressure measuring instrument 419 arranged on the pipeline 411. The cooling water inlet 33 is communicated with the pipeline 411 between the inlet valve 414 and the drain valve 415, and the cooling water outlet 34 is communicated with the pipeline 411 between the drain valve 415 and the outlet valve 416.

[0044] The deoxygenated water tank 412, the circulating cooling pump 413, the inlet valve 414, the drain valve 415, the outlet valve 416, the condenser 417, the inlet flow meter 418, and the temperature and pressure measuring instrument 419 are arranged on the pipeline 411. The deoxygenated water tank 412 is a deionized water bearing container in the test experiment. The circulating cooling pump 413 transports the deionized cooling liquid in the deoxygenated water tank 412 to the container 32, which is heated to a certain temperature by the heat generated by the heating rod 6 to be tested, and then cooled back to the deoxygenated water tank 412 through the condenser 417. The circulating cooling pump 413 controls the cooling flow required by the test experiment. The inlet valve 414 and the outlet valve 416 control the operation boundary of the circulating cooling circuit 41 to the heating rod 6 to be tested. The drain valve 415 is used to empty the deionized cooling liquid in the circulating cooling circuit 41 after the test experiment. The inlet flow meter 418 and the temperature and pressure measuring instrument 419 are used to monitor the flow, temperature and pressure parameters in the circulating cooling circuit 41 in real time, so as to improve the accuracy and safety of the test experiment data.

[0045] The cooling water inlet 33 is communicated with the pipeline 411 between the inlet valve 414 and the drain valve 415, and the cooling water outlet 34 is communicated with the pipeline 411 between the drain valve 415 and the outlet valve 416, so that after the test experiment is finished, the cooling liquid in the cooling water inlet 33 and the cooling water outlet 34 on both sides of the drain valve 415 can flow out through the drain valve 415 by opening the drain valve 415, the residual cooling liquid in the circulating cooling circuit 41 is reduced, and then the circulating cooling circuit 41 can be kept dry after the test experiment is finished, corrosion is reduced, the service life is prolonged, a good experimental environment is provided for the next test experiment, and the accuracy of experimental data is improved.

[0046] Please refer to Figures 1 to 4 In some embodiments, the data acquisition module 5 comprises a central control module 51 and a camera 52, and the central control module 51 is electrically connected with the deoxidized water tank 412, the circulating cooling pump 413, the inlet valve 414, the drain valve 415, the outlet valve 416, the condenser 417, the inlet flow meter 418, the temperature and pressure measuring instrument 419, the camera 52, the liquid level meter 36, the temperature measuring thermocouple 38 and the pressure gauge 37, and the camera 52 collects the changes of the positive and negative electrode insulation layer points of the heating rod 6 to be tested during the experiment.

[0047] The central control module 51 is electrically connected with the deoxidized water tank 412, the circulating cooling pump 413, the inlet valve 414, the drain valve 415, the outlet valve 416, the condenser 417, the inlet flow meter 418, the temperature and pressure measuring instrument 419, the camera 52, the liquid level meter 36, the temperature measuring thermocouple 38 and the pressure gauge 37, so that the changes of temperature, voltage and flow at each place can be more intuitively observed through the central control module 51 in the background, the curve change image is obtained, and the subsequent experimental analysis is facilitated, and better experimental results are obtained. The inlet valve 414, the drain valve 415 and the outlet valve 416 are electrically connected with the central control module 51, so that the inlet valve 414, the drain valve 415 and the outlet valve 416 can be closed or opened by one key through the central control module 51 in the background, and the operation is more simple, convenient and intelligent. The position of the cooling liquid in the container 32 can be more intuitively observed through the liquid level meter 36, and debugging is facilitated. The changes of the positive and negative electrode insulation layer points of the heating rod 6 to be tested during the experiment are collected by the camera 52, the insulating property changes of the positive and negative electrode insulation layer points of the heating rod 6 to be tested with temperature can be more intuitively recorded, the experiment can be timely terminated when mutation occurs, the safety is improved, and subsequent experimental analysis is facilitated.

[0048] Please refer to Figures 1 to 6 In some embodiments of the nuclear heat release electric heating simulation rod insulation performance test experiment method, the following steps are included. S1, placing at least one to-be-tested heating rod 6 into the test assembly 3 and the cooling assembly 4; S2, the test assembly 3 supplies power to the positive electrode point of the to-be-tested heating rod 6 located therein; S3, the test assembly 3 supplies power to the to-be-tested heating rod 6 at a constant rated power, and reduces the cooling capacity of the cooling assembly 4 on the to-be-tested heating rod 6 and the positive and negative electrode insulation layer points; S4, the temperature of the to-be-tested heating rod 6 and the positive and negative electrode insulation layer points continues to rise, the resistance change of the to-be-tested heating rod 6 and the live picture of the positive and negative electrode insulation layer points are observed in real time, when the positive and negative electrode insulation layer points of the to-be-tested heating rod 6 appear mutation and short-circuit insulation failure occurs, the temperature change of the positive and negative electrode insulation layer points of the to-be-tested heating rod 6 at this time is recorded.

[0049] The application places at least one to-be-tested heating rod 6 into the test assembly 3 and the cooling assembly 4 through S1, supplies power to the positive electrode point of the to-be-tested heating rod 6 located therein through S2, supplies power to the to-be-tested heating rod 6 at a constant rated power through S3, and reduces the cooling capacity of the cooling assembly 4 on the to-be-tested heating rod 6 and the positive and negative electrode insulation layer points. The temperature of the to-be-tested heating rod 6 and the positive and negative electrode insulation layer points continues to rise through S4, the resistance change of the to-be-tested heating rod 6 and the live picture of the positive and negative electrode insulation layer points are observed in real time, when the positive and negative electrode insulation layer points of the to-be-tested heating rod 6 appear mutation and short-circuit insulation failure occurs, the temperature change of the positive and negative electrode insulation layer points of the to-be-tested heating rod 6 at this time is recorded. Further, the insulation performance of the to-be-tested heating rod 6 and the minimum unit constituting the electric heating simulation reactor core can be tested before the reactor electric heating reactor core is designed, the insulation failure boundary of the to-be-tested heating rod 6 under the experiment is explored, experimental support is provided for the electric heating simulation reactor core power connection design in the reactor thermal-hydraulic experiment, and the safety of the reactor thermal-hydraulic experiment is ensured.

[0050] Please refer to Figures 1 to 6 In some embodiments, S1 specifically includes: S11, the positive and negative electrode insulation layer points of the to-be-tested heating rod 6 are communicated with the cooling member 42; S12, the lower part of the to-be-tested heating rod 6 is sealed and placed into the circulating cooling loop 41; and S13, the flow of the circulating cooling liquid in the circulating cooling loop 41 is calculated through the rated power of the to-be-tested heating rod 6.

[0051] The flow of the circulating cooling liquid in the circulating cooling loop 41 is calculated through the rated power of the to-be-tested heating rod 6, which can avoid the waste of the cooling liquid in the circulating cooling loop 41, save the use of the cooling liquid, further reduce the cost of the test experiment, and save energy.

[0052] Please refer to Figures 1 to 6In some embodiments, step S2 specifically comprises: S21, the direct current power supply 1 is first electrically connected with the safety device 2; S22, the safety device 2 is then electrically connected with the positive electrode point of the heating rod 6 to be tested; and S23, after the negative electrode point of the heating rod 6 to be tested is in electrical communication with the positioning flange 312, the negative electrode point is electrically connected with the negative electrode grounding end through the wiring end 313.

[0053] The direct current power supply 1 is first electrically connected with the safety device 2, and the safety device 2 is then electrically connected with the positive electrode point of the heating rod 6 to be tested, so that the safety device 2 can avoid damage to the heating rod 6 to be tested when the direct current power supply 1 suddenly changes, thereby improving the stability of the test experiment. When the voltage is too high or the temperature is too high, the power delivery of the direct current power supply 1 is automatically disconnected, which protects the entire nuclear heat release electric heating simulation rod insulation performance test experiment device and improves the safety. After the negative electrode point of the heating rod 6 to be tested is electrically connected with the wiring end 313 of the positioning flange 312, the wiring end 313 provided outside the positioning flange 312 is connected with the copper braid to the negative electrode grounding end, so that the negative electrode point of the heating rod 6 to be tested passes through the positioning flange 312 to the negative electrode grounding end. The negative electrode point on the outer wall surface of the heating rod 6 to be tested is in communication with the positioning flange 312, which can reduce the wiring process, make the installation more convenient and labor-saving, improve the installation efficiency, reduce the risk of wire winding, and improve the safety.

[0054] Please refer to Figures 1 to 6 In some embodiments, step S3 specifically comprises: S31, simultaneously starting the circulating cooling loop 41 and the cooling device 42; S32, gradually increasing the output power of the direct current power supply 1 to the heating rod 6 to be tested until the rated power of the heating rod 6 to be tested is reached, and keeping the rated power unchanged; and S33, keeping the flow of the circulating cooling loop 41 unchanged, and then reducing the cooling capacity of the cooling device 42 to the positive and negative electrode insulation layer points of the heating rod 6 to be tested, so that the temperature at the positive and negative electrode insulation layer points of the heating rod 6 to be tested continuously increases.

[0055] The multiple heating rods 6 to be tested are arranged in the same way as the minimum unit of the electric heating core. The required circulating cooling liquid flow is calculated based on the rated power of the multiple heating rods 6 to be tested. The circulating cooling loop 41 and the cooling device 42 are first started and controlled, so that the rod-level temperature of the heating rod 6 to be tested is stabilized at a stable value. Then the power of the direct current power supply 1 is gradually increased to the rated power of the heating rod 6 to be tested. Then the cooling capacity of the cooling device 42 is dynamically reduced, so that the rod-level temperature of the heating rod 6 to be tested continuously increases. When the resistance of the heating rod 6 to be tested suddenly changes and single-rod insulation failure occurs, the camera 52 monitors the ionization effect between the rods in the picture, and records the rod-level temperature and voltage of the heating rod 6 to be tested at this time, which are the boundary values of the insulation failure of the multiple heating rods 6 to be tested. This provides experimental support for the electric heating simulation core power supply design in the reactor thermal hydraulic experiment, so as to ensure the safety of the reactor thermal hydraulic experiment.

[0056] Referring to Figures 1 to 6 In some embodiments, step S4 specifically comprises: S41, gradually increasing the temperature of the positive and negative electrode insulation layer points of the heating rod 6 to be tested, observing the resistance change of the heating rod 6 to be tested and the positive and negative electrode insulation layer point monitoring picture in real time, when the resistance of the heating rod 6 to be tested and the positive and negative electrode insulation layer points appear to be mutated, insulation failure occurs, and the temperature of the positive and negative electrode insulation layer points of the heating rod 6 to be tested at this time is recorded, which is the temperature boundary value of the insulation failure of the heating rod 6 to be tested; S42, when the heating rod 6 to be tested is in insulation failure, the circulating cooling loop 41 and the cooling member 42 are closed.

[0057] The application records the temperature of the positive and negative electrode insulation layer points of the heating rod 6 to be tested when the resistance of the heating rod 6 to be tested and the positive and negative electrode insulation layer points appear to be mutated, insulation failure occurs, which is the temperature boundary value of the insulation failure of the heating rod 6 to be tested, and explores the temperature boundary of the insulation failure of the heating rod 6 to be tested under the experiment. In the actual application of the heating rod 6 to be tested to the electric heating core design process, the temperature failure boundary of the heating rod to be tested obtained by the above experiment and the temperature-cooling capacity experimental results provide temperature and cooling capacity design criteria for the electric heating core design in the reactor thermal hydraulic experiment. The cooling system cooling capacity of the electric heating core power connection design should control the temperature of the positive and negative electrode insulation layer of the electric heating core below the temperature failure boundary and leave a certain design margin, which can ensure the safety of the electric heating core power connection design and reduce the waste of cooling system resources. It can also enable the electric heating core in the experiment to operate stably in a relatively safe environment, improve safety, and further use the insulation performance test experiment of the heating rod 6 to be tested to provide experimental support for the electric heating simulation core power connection design in the reactor thermal hydraulic experiment, so as to ensure the safety of the reactor thermal hydraulic experiment.

[0058] It can be understood that the above embodiments only express the preferred embodiments of the application, and the description is more specific and detailed, but it cannot be understood as a limitation on the patent scope of the application; it should be pointed out that for ordinary skilled persons in the art, the above technical features can be freely combined without departing from the concept of the application, and some modifications and improvements can be made, which belong to the protection scope of the application; therefore, any equivalent transformation and modification within the scope of the claims of the application shall belong to the scope of the claims of the application.

Claims

1. An experimental apparatus for testing the insulation performance of a nuclear thermoelectric heating simulation rod, characterized in that, include: Test component (3), cooling component (4) and data acquisition module (5); At least one heating rod (6) to be tested is disposed in the test assembly (3); The test component (3) supplies power to the positive terminal of the heating rod (6) under test located therein, and supplies power to the heating rod (6) under test to its rated power; The cooling component (4) provides point cooling and temperature reduction for the heating rod (6) under test and the positive and negative electrode insulation layers; The data acquisition module (5) records in real time the temperature of the heating rod under test (6), the temperature of the negative pole, positive and negative pole insulation layer points, and positive pole of the heating rod under test (6), the voltage and current provided by the test component (3), and the cooling rate and temperature of the positive and negative pole insulation layer points of the heating rod under test (6) by the cooling component (4); The cooling capacity of the cooling component (4) to the positive and negative electrode insulation points of the heating rod (6) under test is reduced, and the temperature of the positive and negative electrode insulation points of the heating rod (6) under test gradually increases until it is broken down. The data acquisition module (5) collects the temperature change of the positive and negative electrode insulation points of the heating rod (6) under test during the breakdown process.

2. The experimental apparatus for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 1, characterized in that, The test assembly (3) includes: a DC power supply (1), a fuse (2), a fixing component (31), and a container (32) connected to the cooling assembly (4). The fixing component (31) fixes the heating rod (6) under test to the container (32). The DC power supply (1) is electrically connected to the positive terminal of the heating rod (6) under test through the fuse (2). The positive and negative insulating layers of the heating rod (6) under test are exposed outside the container (32).

3. The experimental apparatus for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 2, characterized in that, The fixing component (31) includes multiple positioning grids (311) at different heights inside the container (32), and a positioning flange (312) for sealing the end of the container (32) and limiting the position of the heating rod (6) to be tested. The positioning flange (312) is provided with a through hole that allows the heating rod (6) to pass through. The positioning flange (312) is electrically connected to the negative pole of the heating rod (6) to be tested. The positioning flange (312) is provided with a terminal (313) that is electrically connected to the negative grounding terminal.

4. The experimental apparatus for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 3, characterized in that, The container (32) is a cylindrical body. The bottom of the container (32) is provided with a cooling water inlet (33) that communicates with the cooling assembly (4). The upper side of the container (32) is provided with a cooling water outlet (34). The cooling water inside the container (32) is circulated through the cooling assembly (4). The top of the container (32) is provided with a flange sealing surface (35) that is connected to the positioning flange (312). The inner diameter of the cylindrical body is consistent with the inner diameter of the channel in the electric heating core.

5. The experimental apparatus for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 3, characterized in that, The test assembly (3) also includes a level gauge (36) and a pressure gauge (37) installed on the container (32), as well as temperature measuring thermocouples (38) installed at different heights of the container (32) for real-time monitoring of the temperature inside the container (32) at different liquid levels, and the temperature of the positive and negative electrode insulation layer points of the heating rod (6) to be tested.

6. The experimental apparatus for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 4, characterized in that, The cooling assembly (4) includes: a circulating cooling circuit (41) for cooling the lower part of the heating rod (6) under test and a cooling element (42) for cooling the positive and negative electrode insulation layers of the heating rod (6) under test; the circulating cooling circuit (41) is connected to the interior of the container (32), and the cooling element (42) is air-cooled or water-cooled.

7. The experimental apparatus for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 6, characterized in that, The circulating cooling circuit (41) includes: a pipeline (411), and a deaerator tank (412), a circulating cooling pump (413), an inlet valve (414), a drain valve (415), an outlet valve (416), a condenser (417), an inlet flow meter (418), and a temperature and pressure measuring instrument (419) installed on the pipeline (411). The cooling water inlet (33) is connected to the pipeline (411) between the inlet valve (414) and the drain valve (415), and the cooling water outlet (34) is connected to the pipeline (411) between the drain valve (415) and the outlet valve (416).

8. The experimental apparatus for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 7, characterized in that, The data acquisition module (5) includes a central control module (51) and a camera (52). The central control module (51) is electrically connected to the deoxygenated water tank (412), the circulating cooling pump (413), the inlet valve (414), the drain valve (415), the outlet valve (416), the condenser (417), the inlet flow meter (418), the temperature and pressure measuring instrument (419), the camera (52), the level gauge (36), the temperature thermocouple (38), and the pressure gauge (37). The camera (52) collects the changes in the positive and negative insulation layer points of the heating rod (6) under test during the experiment.

9. A method for testing the insulation performance of a nuclear thermoelectric heating simulation rod, characterized in that, Includes the following steps: S1. Place at least one heating rod (6) to be tested into the test assembly (3) and the cooling assembly (4); S2, The test component (3) supplies power to the positive terminal of the heating rod (6) under test located therein; S3. Using the test component (3), the heating rod (6) under test is powered to its rated power and kept constant, thereby reducing the cooling capacity of the cooling component (4) on the heating rod (6) under test and the positive and negative electrode insulation points. S4. The temperature of the heating rod (6) under test and the positive and negative electrode insulation points continues to rise. The resistance change of the heating rod (6) under test and the scene of the positive and negative electrode insulation points are observed in real time. When the positive and negative electrode insulation points of the heating rod (6) under test suddenly change and short circuit insulation failure occurs, the temperature change of the positive and negative electrode insulation points of the heating rod (6) under test is recorded at this time.

10. The experimental method for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 9, characterized in that, Step S1 specifically includes: S11. Connect the positive and negative electrode insulation points of the heating rod (6) to be tested to the cooling element (42); S12. The lower part of the heating rod (6) to be tested is sealed and placed in the circulating cooling circuit (41); S13. The flow rate of the circulating coolant in the circulating cooling circuit (41) is calculated based on the rated power of the heating rod (6) to be tested.

11. The experimental method for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 10, characterized in that, Step S2 specifically includes: S21. The DC power supply (1) is first electrically connected to the fuse (2); S22, the safety device (2) is then electrically connected to the positive terminal of the heating rod (6) to be tested; S23. After the negative pole of the heating rod (6) to be tested is electrically connected to the positioning flange (312), it is electrically connected to the negative grounding terminal through the wiring terminal (313).

12. The experimental method for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 10, characterized in that, Step S3 specifically includes: S31. Simultaneously start the circulating cooling circuit (41) and the cooling component (42). S32. Gradually increase the output power of the DC power supply (1) to the heating rod (6) under test until it reaches the rated power of the heating rod (6) under test, and keep its rated power unchanged. S33. Keep the flow rate of the circulating cooling circuit (41) constant, and then reduce the cooling capacity of the cooling element (42) on the positive and negative electrode insulation points of the heating rod (6) under test, so that the temperature at the positive and negative electrode insulation points of the heating rod (6) under test continues to rise.

13. The experimental method for testing the insulation performance of a nuclear thermoelectric heating simulation rod according to claim 12, characterized in that, Step S4 specifically includes: S41. The temperature of the positive and negative insulation layer points of the heating rod (6) under test gradually increases. The resistance change of the heating rod (6) under test and the monitoring screen are observed in real time. When the resistance of the heating rod (6) under test and the positive and negative insulation layer points change abruptly and insulation failure occurs, the temperature of the positive and negative insulation layer points of the heating rod (6) under test at this time is recorded, which is the temperature boundary value of the insulation failure of the heating rod (6) under test. S42. When the insulation of the heating rod (6) to be tested fails, shut down the circulating cooling circuit (41) and the cooling element (42).

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