Simulation test device for heat transfer and cooling of irradiation channels

Abstract

The present invention discloses a simulation test device for heat transfer and cooling of an irradiation channel. The device comprises: a base; a simulated target, used to simulate a bombardment neutron target in a nuclear reactor, comprising an electric heating element and a heat conductor mounted on the base, the heat conductor being used to transfer heat energy generated by the electric heating element; a holding tank, used to hold coolant; a natural circulation channel, detachably connected between the base and the holding tank, the natural circulation channel being sleeved outside the simulated target and configured to allow coolant in the holding tank to flow through the simulated target in the natural circulation channel to form a natural circulation; a forced circulation channel, connected between the base and the holding tank, the forced circulation channel being sleeved outside the natural circulation channel and configured to allow coolant in the holding tank to form a forced circulation in the forced circulation channel; and a temperature measuring element mounted on the heat conductor to detect temperature changes of the heat conductor during the flow of coolant, thereby simulating and testing the heat conduction and cooling performance of the irradiation channel.

Description

Technical Field

[0001] At least one embodiment of the present invention relates to the field of radiation testing technology, and in particular to a simulation test device for heat transfer and cooling of radiation channels. Background Art

[0002] Before actual engineering application, the materials of nuclear reactor internal components should undergo in-pile identification tests to evaluate the radiation performance of the materials. The radiation performance directly affects the reliability, safety and economy of the nuclear power plant.

[0003] Developing high-performance reactor materials requires extensive, ongoing in-pile irradiation research. Currently, in-pile irradiation performance tests for nuclear reactors are generally divided into four categories: The first is initial screening testing, or individual fuel performance testing. During this phase, a large number of newly developed fuel samples are subjected to comparative irradiation to screen for high-performance fuels and develop fuel irradiation behavior models. The second is comprehensive irradiation testing of selected new fuels under simulated power reactor conditions. The third is irradiation testing of in-pile structural materials. The fourth is the sampling of a certain number of irradiated targets or fuels for hot cell inspection, followed by the selection of representative test pieces for further burnup testing or power transient testing in a research reactor.

[0004] Currently, research related to irradiation testing primarily focuses on irradiation test device design, irradiation test scheme optimization, and post-irradiation inspection technology. For example, in the development of irradiation test devices, independent temperature-compensated high-temperature material irradiation test devices, water-cooled reactor fuel assembly irradiation test devices, and modular, in-core irradiation test devices have been proposed. However, before irradiated materials or material tanks are placed in the reactor for testing, off-core hydraulic verification tests are required to determine whether the coolant flow rate on the fuel rod surface meets design requirements and the stability of the irradiation device structure. This allows for the determination of reasonable off-core device design parameters and off-core heat transfer verification test parameters, as well as device temperature testing under reactor cooling conditions, to support and assist in the in-core safety analysis. Therefore, it is necessary to develop an irradiation test device suitable for in-core irradiation performance testing of nuclear reactor in-core component materials. Summary of the Invention

[0005] In response to existing technical problems, the present invention provides a simulation test device for heat transfer and cooling of irradiation channels, which is designed to at least partially resolve the aforementioned technical issues. By simulating the irradiation channels of a nuclear reactor through natural and forced circulation channels, and using temperature measuring components to detect the temperature changes of the coolant flowing through the natural or forced circulation channels as the simulated target passes through these channels, the device achieves multifunctional simulation testing of the heat conduction and cooling performance of the irradiation channels.

[0006] An embodiment of the present invention provides a simulation test device for heat transfer and cooling of an irradiation channel, comprising: a base; a simulation target, used to simulate a bombardment neutron target in a nuclear reactor, including: an electric heating element, detachably mounted on the base; and a heat conductor, sleeved outside the electric heating element, used to transfer heat energy generated by the electric heating element; a holding pool, located above the base, used to hold a coolant; a natural circulation flow channel, detachably connected between the base and the holding pool and communicated with the holding pool, the natural circulation flow channel being sleeved outside the simulation target and being configured such that the coolant in the holding pool flows through the simulation target in the natural circulation flow channel to form a natural circulation; a forced circulation flow channel, connected between the base and the holding pool and communicated with the holding pool, the forced circulation flow channel being sleeved outside the natural circulation flow channel and being configured such that the coolant in the holding pool forms a forced circulation in the forced circulation flow channel; and a temperature measuring component, mounted on the heat conductor to detect temperature changes of the heat conductor during the flow of the coolant.

[0007] According to the simulation test device for heat transfer and cooling of the irradiation channel provided by the present invention, when conducting an experiment, the electric heating element generates heat after being energized, the heat conductor transfers the heat energy generated by the electric heating element and radiates heat outward, and the coolant in the holding pool enters the natural circulation flow channel. After flowing through the simulated target, the coolant is heated and its density becomes smaller. The coolant with relatively low density flows toward the direction close to the holding pool, and the coolant with relatively high density flows toward the direction close to the base, forming a natural circulation, so that the simulated target and the naturally circulating coolant transfer heat, thereby realizing the test of the heat transfer capacity of the irradiation device under natural circulation conditions.

[0008] In addition, a forced circulation channel is set up around the natural circulation channel of the holding tank to further cool the natural circulation channel. Furthermore, the natural circulation channel is removable. With the natural circulation channel removed, heat transfer between the simulated target and the forced circulation coolant can be achieved, enabling testing of the heat transfer capacity of the irradiation device under forced circulation conditions.

[0009] Among them, the electric heating elements and heat conductors serve as simulated targets in the simulated nuclear reactor experiment, the natural circulation flow channels and forced circulation flow channels simulate the irradiation channels in the nuclear reactor experiment, and the temperature measuring parts detect the temperature changes of the heat conductors during the flow of coolant to simulate the thermal conductivity and cooling performance of the irradiation channels, thereby realizing a multifunctional test of the heat transfer capacity of the irradiation device under natural circulation conditions and forced circulation conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The above contents and other objects, features and advantages of the present application will become more apparent through the following description of the embodiments of the present application with reference to the accompanying drawings, in which:

[0011] Figure 1 2 is a schematic structural diagram of a simulation test device for heat transfer and cooling of radiation channels according to an embodiment of the present invention;

[0012] Figure 2 is a schematic structural diagram of a simulation target and a temperature measuring component according to an embodiment of the present invention;

[0013] Figure 3 is a schematic structural diagram of a simulation target and a temperature measuring component according to another embodiment of the present invention;

[0014] Figure 4 Schematic diagram of the structure of the natural circulation channel and the forced circulation channel according to an embodiment of the present invention.

[0015] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding.

[0016] Description of reference numerals:

[0017] 1. Base;

[0018] 2. Simulated target;

[0019] 21. Electric heating element;

[0020] 22. Heat conducting parts;

[0021] 221, first heat transfer sleeve; 222, second heat transfer sleeve; 223, third heat transfer sleeve;

[0022] 31. Diversion pipe;

[0023] 311, first pipe section; 3111, through hole; 312, second pipe section; 313, first flange; 314, first guide hole;

[0024] 32. Second flow guide pipe;

[0025] 321, second flange; 322, second guide hole;

[0026] 4. Holding pool;

[0027] 51, outer cylinder; 511, first outer cylinder; 5111, drain outlet; 512, second outer cylinder; 513, guide cylinder;

[0028] 52. Reflux pipe;

[0029] 6. Temperature measuring parts;

[0030] 7. Isolation cover. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0032] The present invention is described herein in detail with respect to various embodiments and methods. It should be understood that this is not intended to limit the invention to the specific disclosed embodiments, and that the invention may be practiced using other features, elements, methods, and embodiments. Similar elements in different embodiments are generally designated with similar numbers.

[0033] Developing high-performance reactor materials requires extensive, ongoing in-pile irradiation research. Targets are typically used as targets for neutron bombardment in nuclear reactor experiments. These targets are typically placed within irradiation channels. Before the target or material canister is placed into the reactor for testing, off-pile hydraulic verification tests are conducted to determine whether the coolant flow rate on the target surface meets design requirements and the stability of the target and irradiation channel structures. This allows for the determination of reasonable off-pile device design parameters and off-pile heat transfer verification test parameters, as well as device temperature testing under reactor cooling conditions. This supports and assists with in-pile safety analysis.

[0034] In the related art, most test devices for testing cooling and heat transfer during off-reactor irradiation have relatively simple functions and can only be used to verify the surface heat transfer performance of the irradiation device under forced convection. It is difficult to study the heat transfer characteristics of typical working conditions such as natural convection, air gap heat transfer, and boiling heat transfer. In addition, the test devices in the related art can only be used to simulate the hydraulic parameters of a specific research reactor. If the irradiation channel size is changed, the test device must be reprocessed to adapt to the hydraulic parameters within the corresponding reactor. To this end, an embodiment of the present invention provides a simulation test device for heat transfer and cooling of irradiation channels to at least partially solve the above-mentioned technical problems.

[0035] Figure 1 3 is a schematic structural diagram of a simulation test device for heat transfer and cooling of radiation channels according to an embodiment of the present invention.

[0036] The embodiment of the present invention provides a simulation test device for heat transfer and cooling of irradiated channels, such as Figure 1 As shown, the simulation test device for heat transfer and cooling of the irradiation channel includes a base 1, a simulation target 2, a holding pool 4, a natural circulation channel, a forced circulation channel and a temperature measuring component 6.

[0037] like Figure 1 As shown, the simulated target 2 is used to simulate a bombardment neutron target in a nuclear reactor, and includes an electric heating element 21 and a heat conductor 22. The electric heating element 21 is detachably mounted on the base 1, and the heat conductor 22 is sleeved on the outside of the electric heating element 21 to transfer the heat energy generated by the electric heating element 21.

[0038] The holding pool 4 is located above the base 1 and is used to hold the coolant. The natural circulation channel is detachably connected between the base 1 and the holding pool 4 and is communicated with the holding pool 4. The natural circulation channel is sleeved outside the simulated target 2 and is configured so that the coolant in the holding pool 4 flows through the simulated target 2 in the natural circulation channel to form a natural circulation. The forced circulation channel is connected between the base 1 and the holding pool 4 and is communicated with the holding pool 4. The forced circulation channel is sleeved outside the natural circulation channel and is configured so that the coolant in the holding pool 4 forms a forced circulation in the forced circulation channel. The temperature measuring part 6 is installed on the heat conductor 22 to detect the temperature change of the heat conductor 22 during the flow of the coolant.

[0039] According to the simulation test device for heat transfer and cooling of the irradiation channel provided in this embodiment, when conducting the experiment, the electric heating element 21 generates heat after being energized, the heat conductor 22 absorbs the heat energy generated by the electric heating element 21 and radiates heat outward, and the coolant in the holding pool 4 enters the natural circulation flow channel. The coolant flowing through the simulated target 2 becomes less dense after being heated. The coolant with relatively low density flows toward the direction close to the holding pool 4, that is, it flows upward, and the coolant with relatively high density flows toward the direction close to the base 1, that is, it flows downward, thereby forming a natural circulation.

[0040] Furthermore, the coolant in the holding tank 4 forms a forced circulation around the periphery of the natural circulation channel, further cooling the heated coolant within the natural circulation channel. Furthermore, the natural circulation channel is removable, allowing heat transfer between the simulated target and the forced circulation coolant.

[0041] The electric heating element 21 and heat conductor 22 simulate the simulated target 2 used in nuclear reactor experiments, the natural circulation channel and the forced circulation channel simulate the irradiation channel used in nuclear reactor experiments, and the temperature measuring element 6 detects the temperature change of the heat conductor 22 during the flow of coolant to simulate and test the heat conduction and cooling performance of the irradiation channel. By providing a removable natural circulation channel within the forced circulation channel, the embodiments of the present invention enable testing of the heat transfer capacity of the irradiation device under both forced and natural circulation conditions, thus achieving multifunctionality of the simulation test device.

[0042] Figure 2 Schematic diagram of the structure of a simulation target and a temperature measuring component according to an embodiment of the present invention. Figure 3 3 is a schematic structural diagram of a simulation target and a temperature measuring component according to another embodiment of the present invention.

[0043] In an exemplary embodiment, Figure 1 As shown, the base 1 is arranged horizontally, and a slot is formed in the middle of the base 1 to facilitate replacement of simulated targets 2 of different sizes according to actual needs. The simulated target 2 is used to simulate the bombardment neutron target in a nuclear reactor, and includes an electric heating element 21 and a heat conductor 22.

[0044] Specifically, the material of the electric heating element 21 can be stainless steel or molybdenum, which has a high melting point. The electric heating element 21 is detachably mounted on the base 1 and placed vertically. The heat conductor 22 is mounted outside the electric heating element 21 and is used to transfer the heat energy generated by the electric heating element 21. To ensure that the heat conductor 22 has a high melting point, the material of the heat conductor 22 can be aluminum, molybdenum, or tungsten, etc., without specific limitation herein.

[0045] In an exemplary embodiment, Figure 2 As shown, the heat conducting member 22 may include a first heat transfer sleeve 221, which is sleeved outside the electric heating element 21 to transfer heat energy generated by the electric heating element 21. In some embodiments, the inner surface of the first heat transfer sleeve 221 contacts the electric heating element 21 to improve heat transfer efficiency.

[0046] In an exemplary embodiment, Figure 3 As shown, the heat conducting member 22 may include a second heat transfer sleeve 222 and a third heat transfer sleeve 223. The second heat transfer sleeve 222 is sleeved outside the electric heating element 21, and the third heat transfer sleeve 223 is sleeved outside the second heat transfer sleeve 222. In some embodiments, the inner surface of the second heat transfer sleeve 222 contacts the electric heating element 21 to improve heat transfer efficiency.

[0047] In an exemplary embodiment, Figure 2 and Figure 3 As shown, the outer diameter of the third heat transfer sleeve 223 is equal to the outer diameter of the first heat transfer sleeve 221, and the inner diameter of the first heat transfer sleeve 221 is equal to the inner diameter of the second heat transfer sleeve 222. For example, the first heat transfer sleeve 221 has an inner diameter of 10.0 mm, an outer diameter of 37.8 mm, and a length of 180 mm; the second heat transfer sleeve 222 has an inner diameter of 10.0 mm, an outer diameter of 18.0 mm, and a length of 180 mm; and the third heat transfer sleeve 223 has an inner diameter of 18.0 mm, an outer diameter of 37.8 mm, and a length of 180 mm. When the third heat transfer sleeve is sleeved outside the second heat transfer sleeve, the outer diameter of the third heat transfer sleeve 223 is equal to the outer diameter of the first heat transfer sleeve.

[0048] When the heat conductor 22 is a first heat transfer sleeve, the temperature measuring element 6 obtains the temperature of the heat conductor 22 to obtain a first test temperature. When the heat conductor 22 includes a second heat transfer sleeve 222 and a third heat transfer sleeve 223, the temperature measuring element 6 obtains the temperature of the heat conductor 22 to obtain a second test temperature. The first test temperature is compared with the second test temperature to obtain the influence of the gas gap between the second heat transfer sleeve 222 and the third heat transfer sleeve 223 on the heat transfer of the heat conductor 22.

[0049] In an exemplary embodiment, Figure 2 and Figure 3As shown, the temperature measuring element 6 includes a thermocouple and temperature measuring leads, which can accurately measure the temperature of the thermal conductor 22. Multiple temperature measuring elements 6 can be provided, and the multiple temperature measuring elements 6 are evenly spaced at different diameters of the circumference of the thermal conductor 22. The evenly spaced distribution of the temperature measuring elements 6 enables the acquisition of temperature data at different diameters of the circumference of the thermal conductor 22, thereby improving the comprehensiveness of the temperature data collected by the temperature measuring elements 6. In some embodiments, within the thermal conductor 22, multiple temperature measuring elements 6 are symmetrically arranged on each of the aforementioned circumferences, thereby improving the comprehensiveness and accuracy of the temperature data collected by the temperature measuring elements 6.

[0050] In an exemplary embodiment, the spacing between two adjacent circles where the temperature measuring element 6 is located is equal to obtain the temperature of the heat conductor 22 with different gradients along the radial direction. The temperature measuring elements 6 are evenly spaced along the radial direction to obtain temperature data of the heat conductor 22 with different gradients, thereby improving the comprehensiveness and regularity of the temperature data collected by the temperature measuring element 6.

[0051] In an exemplary embodiment, Figure 1 As shown, the simulation test apparatus further includes an isolation cover 7. The isolation cover 7 is removably and hermetically connected to the base 1 and covers the heat conducting member 22. The isolation cover 7 is spaced apart from the heat conducting member 22 to isolate the coolant from the isolation cover 7 and prevent the heat conducting member 22 from coming into contact with the coolant. Optionally, the bottom of the isolation cover 7 is hermetically mounted to the base 1 via a flange.

[0052] In an exemplary embodiment, the isolation cover 7 is evacuated to a vacuum state, and then filled with an inert gas, thereby isolating the coolant and the heat conducting member 22 through the inert gas.

[0053] According to an embodiment of the present disclosure, the isolation cover 7 isolates the heat conductor 22 from the coolant, and the inert gas is filled in the isolation cover 7 to further isolate the heat conductor 22 and reduce the degree of heat transfer between the heat conductor 22 and air or oxygen.

[0054] In this embodiment, under the working condition that the isolation cover 7 is present, the temperature measuring component 6 obtains the temperature data when the heat conductor 22 is isolated from the coolant, and forms a comparative experiment with the temperature data obtained by the temperature measuring component 6 under the working condition that the heat conductor 22 is in direct contact with the coolant, so as to realize the test of the heat transfer capacity of the internal liquid gap of the simulated target 2 and the irradiation channel.

[0055] In an exemplary embodiment, Figure 1 As shown, a holding pool 4 containing coolant is placed above the base 1. The natural circulation channel is configured such that the coolant in the holding pool 4 is heated when flowing through the simulated target 2 to form a natural circulation by virtue of density difference.

[0056] Specifically, the simulation test device includes a first flow conduit 31 and a second flow conduit 32. The first flow conduit 31 and the second flow conduit 32 can be made of aluminum alloy material, so that it has a low density and good thermal conductivity, which is not limited here. Among them, the first flow conduit 31 is connected between the bottom of the holding pool 4 and the base 1, and is sleeved outside the heat conductor 22, and the first flow conduit 31 is connected to the holding pool 4, and the bottom of the first flow conduit 31 is provided with a through hole 3111 near the base 1. The second flow conduit 32 is connected between the bottom of the holding pool 4 and the base 1, and is sleeved outside the first flow conduit 31, and the second flow conduit 32 is connected to the inside of the first flow conduit 31 through the through hole 3111, and the second flow conduit 32 is connected to the holding pool 4.

[0057] According to an embodiment of the present disclosure, a natural circulation flow channel is formed inside the first flow conduit 31 and between the first flow conduit 31 and the second flow conduit 32. When conducting an experiment, the coolant in the holding pool 4 enters the natural circulation flow channel to cool the simulated target 2. Specifically, the coolant in the holding pool 4 flows downward into the first flow conduit 31 and enters the second flow conduit 32 through the through hole 3111. The coolant is heated and its density decreases when flowing through the heat conductor 22, so that the coolant can rely on its own density difference to flow back to the holding pool 4 along the flow channel between the first flow conduit 31 and the second flow conduit 32, thereby realizing the natural circulation of the coolant and cooling the simulated target 2.

[0058] Figure 4 2 is a top view of a natural circulation channel and a forced circulation channel according to an embodiment of the present invention.

[0059] In an exemplary embodiment, Figure 1 and Figure 4 As shown, the first flow guide tube 31 includes a first tube section 311 and a second tube section 312. The first tube section 311 is connected to the base 1 and is arranged outside the electric heating element 21. One end of the second tube section 312 is connected to the top of the first tube section 311, and the other end is installed at the end of the second flow guide tube 32 near the holding tank 4. The diameter of the second tube section 312 is smaller than that of the first tube section 311, which reduces the resistance to the upward flow of the relatively low-density coolant and improves the natural circulation capacity.

[0060] In some embodiments, a first flange 313 is connected between one end of the first flow guide tube 31 close to the holding tank 4 and the second flow guide tube 32. A plurality of first flow guide holes 314 are provided through the first flange 313. The first flow guide holes 314 are used to provide a channel for the coolant to circulate between the first flow guide tube 31 and the second flow guide tube 32 to the holding tank 4.

[0061] Specifically, the first flange 313 is integrally provided at the top of the second pipe section 312 and can be bolted to the top of the second flow guide pipe 32. Furthermore, a plurality of first flow guide holes 314 can be evenly spaced along the circumference of the first flange 313, allowing the coolant between the first flow guide pipe 31 and the second flow guide pipe 32 to flow into the holding tank 4.

[0062] Optionally, the height of the first flow conduit 31 ranges from 4000 mm to 6000 mm, for example, 4000 mm, 4500 mm, 5000 mm, 5500 mm, or 6000 mm, providing a sufficient gravity differential to meet natural circulation requirements. Based on experimental requirements, the first flow conduit 31 can be replaced by adjusting the length and diameter of the first and second pipe sections 311, 312 to conduct comparative experiments and test the effect of the dimensions of the first flow conduit 31 on the thermal conductivity and cooling performance of the irradiation channels. Based on the experimental results, the first flow conduit 31 and, consequently, the irradiation channels can be optimized.

[0063] In an exemplary embodiment, Figure 1 and Figure 4 As shown, the bottom ends of the first flow guide pipe 31 , the second flow guide pipe 32 and the isolation cover 7 are all connected to the base 1 through connecting flanges, wherein the connecting flange of the second flow guide pipe 32 is located above the connecting flange of the isolation cover 7 .

[0064] In an exemplary embodiment, Figure 1 As shown, the forced circulation channel is configured so that the coolant in the holding tank 4 forms a forced circulation around the natural circulation channel. In this embodiment, the simulation test device also includes an outer cylinder 51, a return pipe 52 and a fluid driver. The outer cylinder 51 is connected between the bottom of the holding tank 4 and the base 1, and is sleeved outside the second guide pipe 32, and the outer cylinder 51 is connected to the holding tank 4 and isolated from the second guide pipe 32. The return pipe 52 is connected between the outer cylinder 51 and the holding tank 4, and the fluid driver is installed on the return pipe 52 for returning the coolant in the outer cylinder 51 to the holding tank 4 to achieve forced circulation.

[0065] In an exemplary embodiment, Figure 1As shown, the outer cylinder 51 includes a first outer cylinder 511, a second outer cylinder 512, and a guide tube 513. The first outer cylinder 511 is mounted on the base 1 and is provided with a drain outlet 5111. The return pipe 52 is connected between the drain outlet 5111 and the holding tank 4. The second outer cylinder 512 is mounted on the end of the first outer cylinder 511 away from the base 1 and is connected to the holding tank 4. The guide tube 513 is located inside the outer cylinder 51 and is connected to the connection between the first outer cylinder 511 and the second outer cylinder 512. It extends downward to below the entrance of the drain outlet 5111 to guide the coolant between the second outer cylinder 512 and the second guide pipe 32 to flow through the flow channel between the second guide pipe 32 and the guide tube 513 and the flow channel between the guide tube 513 and the first outer cylinder 511 in sequence, and then flow out from the drain outlet 5111.

[0066] In some embodiments, the bottom end of the first outer cylinder 511 is mounted on the base 1 via a connecting flange, and the connecting flange of the first outer cylinder 511 is located above the connecting flange of the second flow guide tube 32. In addition, the second outer cylinder 512 can also be mounted on the top end of the first outer cylinder 511 via a flange.

[0067] According to an embodiment of the present disclosure, the coolant in the holding tank 4 enters the outer cylinder 51 through the second guide hole 322. The coolant then flows along the outer cylinder 51 to between the guide cylinder 513 and the second guide pipe 32. The coolant then hits the base 1 and returns to flow between the guide cylinder 513 and the first outer cylinder 511. Subsequently, under the action of the fluid driver, the coolant flows through the drain port 5111 and along the return pipe 52 into the holding tank 4, forming a forced circulation, further cooling the natural circulation flow channel. The fluid driver can be a pump.

[0068] In some embodiments, a second flange 321 is connected between the end of the second flow conduit 32 proximal to the holding tank 4 and the outer cylinder 51. A plurality of second flow guide holes 322 are provided through the second flange 321 to provide a passage for coolant in the holding tank 4 to flow between the outer cylinder 51 and the second flow conduit 32. Specifically, the top end of the second flow conduit 32 is connected to the second flange 321, and the other side of the second flange 321, opposite the second flow conduit 32, abuts against the inner surface of the outer cylinder 51.

[0069] In an exemplary embodiment, the first guide tube 31 and the second guide tube 32 can be removed, and the coolant located in the outer cylinder 51 directly contacts the simulated target 2 or the isolation cover 7. Under the condition that the forced circulation channel directly cools the simulated target 2 or the isolation cover 7, the temperature measuring component 6 obtains the temperature data of the heat conductor 22 during the flow of the coolant, thereby realizing the test of the heat transfer capacity of the irradiation channel and the simulated target 2 under the condition of the forced circulation channel.

[0070] According to the simulation test device for heat transfer and cooling of the irradiation channel provided in this embodiment, when conducting the experiment, the electric heating element 21 generates heat after being energized, the heat conductor 22 transfers the heat energy generated by the electric heating element 21 and radiates heat outward, and the coolant in the holding pool 4 enters the natural circulation flow channel. The coolant flowing through the simulated target 2 becomes less dense after being heated. The coolant with relatively low density flows toward the direction close to the holding pool 4, and the coolant with relatively high density flows toward the direction close to the base 1, forming a natural circulation.

[0071] In addition, the coolant in the holding pool 4 forms a forced circulation around the periphery of the natural circulation channel, further cooling the natural circulation channel. The electric heating element 21 and the heat conductor 22 simulate the simulated target 2 in a nuclear reactor experiment, the natural circulation channel and the forced circulation channel simulate the irradiation channel in a nuclear reactor experiment, and the temperature measuring element 6 detects the temperature change of the heat conductor 22 during the flow of the coolant to simulate the thermal conductivity and cooling performance of the irradiation channel. Therefore, by using the simulation test device in the embodiment of the present invention, reasonable off-core device design parameters and off-core heat transfer verification test parameters can be determined, and device temperature testing that meets reactor cooling conditions can be completed, supporting and assisting in-core safety analysis.

[0072] The above specific embodiments further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A simulation test device for heat transfer and cooling of irradiated channels, characterized in that: include: Base (1); A simulated target (2) is used to simulate a bombardment neutron target in a nuclear reactor, comprising: an electric heating element (21) detachably mounted on the base (1); and a heat conducting member (22), which is sleeved outside the electric heating element (21) and is used to transfer heat energy generated by the electric heating element (21); A holding tank (4), located above the base (1), for holding a coolant; A natural circulation channel is detachably connected between the base (1) and the holding pool (4) and is in communication with the holding pool (4); the natural circulation channel is sleeved outside the simulated target (2) and is configured such that the coolant in the holding pool (4) flows through the simulated target (2) in the natural circulation channel to form a natural circulation; a forced circulation channel connected between the base (1) and the holding pool (4) and in communication with the holding pool (4); the forced circulation channel being sleeved outside the natural circulation channel and configured such that the coolant in the holding pool (4) forms a forced circulation in the forced circulation channel; and A temperature measuring element (6) is installed on the heat conducting element (22) to detect temperature changes of the heat conducting element (22) during the flow of the cooling liquid.

2. The device according to claim 1, characterized in that Also includes: a first flow guide pipe (31), connected between the bottom of the holding pool (4) and the base (1) and sleeved outside the heat conducting member (22); the first flow guide pipe (31) is in communication with the holding pool (4); and a through hole (3111) is provided in the first flow guide pipe (31) near the base (1); and a second flow guide pipe (32), connected between the bottom of the holding pool (4) and the base (1), and sleeved outside the first flow guide pipe (31), and communicating with the interior of the first flow guide pipe (31) through the through hole (3111), and the second flow guide pipe (32) is in communication with the holding pool (4); The natural circulation flow channel is formed inside the first flow guide pipe (31) and between the first flow guide pipe (31) and the second flow guide pipe (32).

3. The device according to claim 2, characterized in that The first flow guide tube (31) comprises: A first pipe section (311) is connected to the base (1) and is sleeved outside the electric heating element (21); A second pipe section (312) has one end connected to the first pipe section (311) and the other end installed on one end of the second flow guide pipe (32) close to the holding tank (4), and the diameter of the second pipe section (312) is smaller than the diameter of the first pipe section (311).

4. The device according to claim 2, characterized in that Also includes: An outer cylinder (51) is connected between the bottom of the holding pool (4) and the base (1), and is sleeved outside the second flow guide pipe (32). The outer cylinder (51) is connected to the holding pool (4) and isolated from the second flow guide pipe (32). a return pipe (52) connected between the outer cylinder (51) and the holding tank (4); and a fluid driver, mounted on the return pipe (52), for transporting the cooling liquid in the outer cylinder (51) back to the holding tank (4); The interior of the outer cylinder (51) and the return pipe (52) form the forced circulation channel, and the cooling liquid in the holding tank (4) flows downward into the outer cylinder (51) and is sent back to the holding tank (4) via the return pipe (52) by the fluid driver.

5. The device according to claim 4, characterized in that The outer cylinder (51) comprises: A first outer cylinder (511) is mounted on the base (1); the first outer cylinder (511) is provided with a drain outlet (5111); the return pipe (52) is connected and arranged between the drain outlet (5111) and the holding tank (4); a second outer cylinder (512), mounted on an end of the first outer cylinder (511) away from the base (1) and connected to the containing tank (4); and A guide tube (513) is connected to the connection between the first outer cylinder (511) and the second outer cylinder (512) and extends downward to below the drain port (5111) to guide the coolant between the second outer cylinder (512) and the second guide pipe (32) to flow through the flow channel between the second guide pipe (32) and the guide tube (513) and the flow channel between the guide tube (513) and the first outer cylinder (511) in sequence, and to flow out from the drain port (5111).

6. The device according to any one of claims 1 to 5, characterized in that Also includes: An isolation cover (7) is detachably sealed and connected to the base (1) and is arranged outside the heat conducting member (22). The isolation cover (7) and the heat conducting member (22) are spaced apart to isolate the coolant outside the isolation cover (7).

7. The device according to claim 6, characterized in that The isolation cover (7) is configured to be filled with an inert gas in a vacuum state.

8. The device according to any one of claims 1 to 5, characterized in that A plurality of temperature measuring elements (6) are provided, and the plurality of temperature measuring elements (6) are evenly distributed at circumferences of different diameters of the heat conducting element (22).

9. The device according to claim 8, characterized in that The distances between the two adjacent circles where the temperature measuring components (6) are located are equal, so as to obtain the temperatures of the heat conducting component (22) with different gradients along the radial direction.

10. The device according to any one of claims 1 to 5, characterized in that The heat-conducting member (22) comprises a first heat-transfer sleeve (221), and the first heat-transfer sleeve (221) is sleeved outside the electric heating element (21) to transfer heat energy of the electric heating element (21).

11. The device according to any one of claims 1 to 5, characterized in that The heat-conducting member (22) comprises a second heat-conducting sleeve (222) and a third heat-conducting sleeve (223), wherein the second heat-conducting sleeve (222) is sleeved outside the electric heating element (21), and the third heat-conducting sleeve (223) is sleeved outside the second heat-conducting sleeve (222).

12. The device according to claim 2, characterized in that A first flange (313) is connected between one end of the first flow guide pipe (31) close to the holding pool (4) and the second flow guide pipe (32), and a plurality of first flow guide holes (314) are provided through the first flange (313) for providing a channel for the coolant between the first flow guide pipe (31) and the second flow guide pipe (32) to circulate to the holding pool (4).

13. The device according to claim 4, characterized in that A second flange (321) is connected between the end of the second guide pipe (32) close to the holding pool (4) and the outer cylinder (51), and a plurality of second guide holes (322) are provided through the second flange (321) for providing a channel for the coolant in the holding pool (4) to flow between the outer cylinder (51) and the second guide pipe (32).

Images