A device and method for analyzing the performance of a cross-shaped torsion fuel assembly.

Abstract

This application provides a performance analysis device and method for a cross-shaped torsion fuel assembly, comprising: an experimental barrel, the experimental barrel having a hollow structure, wherein multiple experimental rods are arranged axially along the experimental barrel in a rod bundle flow channel array, and all the experimental rods have the same torsion angle, with sub-channels formed between adjacent experimental rods; and a water supply loop assembly connected to a first end of the experimental barrel. The beneficial effect of this application is that by setting up the water supply loop assembly, fluid recovery assembly, tracer inlet assembly, tracer recovery assembly, and measurement and calculation assembly, and by selecting different numbers and positions of inlet pipes and conducting multiple experiments, the mixing model of the central region and the sidewall region of the cross-shaped torsion fuel assembly can be clarified by quantitatively comparing the concentration distribution of sub-channels at different cross-sections.

Description

Technical Field

[0001] This application belongs to the technical field of pressurized water reactor fuel elements, specifically relating to a performance analysis device and method for a cross-shaped twisted fuel assembly. Background Technology

[0002] The cross-shaped torsion fuel rod cross section consists of ribs, rib roots, and connecting sections, and is periodically torsion around its axis. Adjacent fuel rods are supported by periodic contact points of the ribs, eliminating the need for additional positioning grids. It combines low flow resistance with continuous mixing enhancement and has been applied in some advanced nuclear power plants. Lateral mixing characteristics are a core research dimension for the optimized design and safety analysis of cross-shaped torsion fuel rods. A significant feature is that the coolant is impeded by the torsion structure between the rods, continuously forming a secondary flow within the rod bundle channel to promote lateral mixing in the sub-channels. Furthermore, the rod gap in the central region of the assembly is affected by the combined secondary flow of two fuel rods, while the sidewall region is only affected by the secondary flow of a single fuel rod. This results in a fundamental difference in the mixing models between the two regions. Lateral mixing dominated by secondary flow is a key parameter for analyzing fuel assembly sub-channels, and currently, there is a lack of suitable mixing performance analysis equipment. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0004] To address the aforementioned problems, the first aspect of this application provides a performance analysis device for a cross-shaped torsion fuel assembly, comprising: The experimental barrel is a hollow structure. Multiple experimental rods are arranged at intervals along the axial direction in a rod bundle flow channel array. All the experimental rods have the same twist angle, and sub-channels are formed between adjacent experimental rods. A water supply circuit assembly is connected to the first end of the experimental tank and is used to supply deionized water into the experimental tank. A fluid recovery assembly is connected to the second end of the experimental tank and is used to recover deionized water flowing through the experimental tank. The tracer delivery assembly includes a tracer storage tank and delivery tubes. Multiple delivery tubes are disposed at the bottom of the experimental barrel. The tracer storage tank is connected to the delivery tubes, and an experimental rod is disposed at the center of every four delivery tubes. A tracer recovery assembly includes multiple collection tanks and multiple outlet tubes. The outlet tubes are located on the top of the experimental tank and are matched with the positions of the inlet tubes. Each collection tank is connected to a corresponding outlet tube for recovering the mixed solution at the corresponding position of each inlet tube. A measurement and calculation component is used to detect the mixed solution in each collection tank and calculate the concentration value of the tracer in each collection tank based on the detection results; In this process, tracers are injected directionally into the experimental container by selecting different numbers and positions of the inlet tubes. After the tracers have completed lateral mixing in the experimental container, the mixed solution is introduced into the corresponding collection tank through all the outlet tubes. The concentration value of the tracer in each collection tank is accurately calculated by the measurement and calculation component. Based on the concentration value data, the concentration distribution of sub-channels at different cross-sections is quantitatively compared.

[0005] Optionally, the experimental container includes: The barrel body has a first fixing member and a second fixing member respectively provided on its upper and lower sides. The first fixing member includes a first positioning plate and a first fixing rod. The first positioning plate is provided on the top of the barrel body. The first positioning plate has a plurality of first fixing holes. The first fixing rod is provided in the first fixing holes. The second fixing member includes a second positioning plate and a second fixing rod. The second positioning plate is disposed at the bottom of the barrel body. A plurality of second fixing holes are opened on the second positioning plate at the matching position of the first fixing hole. The second fixing rod is disposed in the second fixing holes. The experimental rod is positioned between the first positioning plate and the second positioning plate, and the first fixing rod and the second fixing rod are connected to the experimental rod.

[0006] Optionally, it also includes: a first sealing plate, the first sealing plate being disposed on the side of the first fixing member away from the barrel body, the first sealing plate having an outlet hole, the outlet pipe being disposed in the outlet hole and communicating with the barrel body; The second sealing plate is disposed on the side of the second fixing member away from the barrel body. The second sealing plate has an inlet hole, and the inlet pipe is disposed in the inlet hole and connected to the barrel body.

[0007] Optional, the water supply loop assembly includes: Storage water tank; The water supply pipeline includes an inlet pipe on the tank body, which is located between the storage tank and the inlet pipe. A first pump body, a first water supply mass flow meter, and a water supply control valve are sequentially installed on the water supply pipeline.

[0008] Optionally, the fluid recovery assembly includes: Wastewater tank; A drainage pipe is provided on the tank body and above the inlet pipe. The drainage pipe is located between the wastewater tank and the outlet pipe, and a drainage control valve is provided on the drainage pipe.

[0009] Optionally, the tracer delivery component further includes: A connecting pipeline is provided between the inlet pipe and the tracer storage tank, and a second pump body, a second mass flow meter and a first control valve are sequentially provided on the connecting pipeline.

[0010] Optionally, the tracer recovery assembly further includes: A collection pipeline is provided between each of the collection tanks and the corresponding outlet pipe, and a second control valve is provided on the collection pipeline.

[0011] Optionally, the measurement and calculation components include a conductivity meter, a temperature sensor, and a data processing module. The conductivity meter and the temperature sensor are used to measure the conductivity and temperature values ​​of the mixed solution in each of the collection tanks. The data processing module calculates the tracer concentration value in each of the collection tanks based on the detected conductivity and temperature values.

[0012] Optionally, the number of experimental rods is 16, and the number of inlet tubes and outlet tubes are 25 each.

[0013] This application also provides a method for performance analysis of a cross-shaped torsion fuel assembly, employing any of the above-mentioned cross-shaped torsion fuel assembly performance analysis devices, including the following steps: S1. Start the first pump of the water supply circuit assembly, and deliver deionized water into the experimental tank through the water supply pipeline, and control the mass flow rate in the water supply pipeline within the target range. After the deionized water fills the experimental tank, it continues to flow for the target time to remove non-condensable gases in the experimental tank. During this period, the deionized water flowing out of the experimental tank is discharged into the wastewater tank through the drain pipeline. S2. Select one or more of the inlet tubes according to the experimental plan, open the first control valve on the connecting pipe at the selected location, and start the second pump to discharge the tracer in the tracer storage tank into the experimental bucket through the selected inlet tube. During this process, the mass flow rate in the connecting pipe is the same as the mass flow rate in the water supply pipe. S3. After the tracer is injected and flows stably in the experimental barrel for a certain period of time, open the second control valve on each of the collection pipelines, and collect the mixed solution in the experimental barrel at the target time through the collection tank corresponding to the outlet pipe. S4. The temperature and conductivity values ​​of the mixed solution in each of the collection tanks are measured by the temperature sensor and conductivity meter of the measurement and calculation component. The data processing module calculates the tracer concentration value in each of the collection tanks based on the detected conductivity and temperature values, and quantitatively compares the sub-channel concentration distribution of different cross-sections based on the concentration data.

[0014] Beneficial effects The embodiments of the present invention provide a performance analysis device and method for a cross-shaped torsion fuel assembly. By setting up a water supply circuit assembly, a fluid recovery assembly, a tracer inlet assembly, a tracer recovery assembly, and a measurement and calculation assembly, and by selecting different numbers and positions of inlet pipes and conducting multiple experiments, the mixing model of the central region and the sidewall region of the cross-shaped torsion fuel assembly is clarified by quantitatively comparing the concentration distribution of sub-channels with different cross-sections. The mass balance relationship of all sub-channels is established in combination with experimental boundary conditions, and the equivalent mixing coefficient of the fuel assembly is finally obtained by using the least squares method. Attached Figure Description

[0015] Figure 1 This is a front view structural diagram of the present invention; Figure 2 This is a structural diagram of the experimental barrel of the present invention; Figure 3 This is a structural diagram of the first positioning plate of the present invention; Figure 4 This is a structural diagram of the first sealing plate of the present invention; Figure 5 This is a front view of the experimental rod of the present invention; Figure 6 This is a cross-sectional structural diagram of the experimental rod of the present invention; Figure 7 This is a flowchart of another embodiment of the present invention.

[0016] The reference numerals in the attached figures are as follows: 1. Experimental barrel; 11. Barrel body; 12. First fixing component; 121. First positioning plate; 122. First fixing rod; 13. Second fixing component; 131. Second positioning plate; 132. Second fixing rod; 14. First sealing plate; 15. Second sealing plate; 2. Experimental rod; 3. Water supply circuit assembly; 31. Storage tank; 32. Water supply pipeline; 33. First pump body; 34. First water supply mass flow meter; 35. Water supply control valve; 4. Fluid recovery assembly; 41. Wastewater tank; 42. Drainage pipeline; 43. Drainage control valve; 5. Tracer inlet assembly; 51. Tracer storage tank; 52. Inlet pipe; 53. Connecting pipeline; 54. Second pump body; 55. Second mass flow meter; 56. First control valve; 6. Tracer recovery assembly; 61. Collection tank; 62. Outlet pipe; 63. Collection pipeline; 64. Second control valve. Detailed Implementation

[0017] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0018] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0019] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0020] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0021] See also Figure 1-6 As shown, according to an embodiment of this application, a first aspect provides a performance analysis device for a cross-shaped torsion fuel assembly, comprising: Experimental barrel 1, the experimental barrel 1 is a hollow structure, and multiple experimental rods 2 are arranged at intervals along the axial direction in a rod bundle flow channel array, and all the experimental rods 2 have the same twist angle, and sub-channels are formed between adjacent experimental rods 2. Water supply circuit assembly 3 is connected to the first end of the experimental tank 1 and is used to supply deionized water into the experimental tank 1. Fluid recovery component 4 is connected to the second end of the experimental tank 1 and is used to recover the deionized water flowing through the experimental tank 1; The tracer delivery component 5 includes a tracer storage tank 51 and an inlet tube 52. Multiple inlet tubes 52 are disposed at the bottom of the experimental barrel 1. The tracer storage tank 51 is connected to the inlet tubes 52, and an experimental rod 2 is disposed at the center of every four inlet tubes 52. The tracer recovery assembly 6 includes multiple collection tanks 61 and multiple outlet tubes 62. The outlet tubes 62 are disposed on the top of the experimental barrel 1 and are matched with the position of the inlet tube 52. Each collection tank 61 is connected to the corresponding outlet tube 62 for recovering the mixed solution at the corresponding position of each inlet tube 52. A measurement and calculation component is used to detect the mixed solution in each collection tank 61 and calculate the concentration value of the tracer in each collection tank 61 based on the detection results; In this process, tracers are injected directionally into the experimental tank 1 by selecting different numbers and positions of the inlet tubes 52. After the tracers have completed lateral mixing in the experimental tank 1, the mixed solution is introduced into the corresponding collection tank 61 through all the outlet tubes 62. The concentration value of the tracer in each collection tank 61 is accurately calculated by the measurement and calculation component. Based on the concentration value data, the concentration distribution of sub-channels at different cross-sections is quantitatively compared.

[0022] In this technical solution, the cross-shaped torsion fuel assembly performance analysis device provided in this application embodiment includes an experimental tank 1, a water supply circuit assembly 3, a fluid recovery assembly 4, a tracer inlet assembly 5, a tracer recovery assembly 6, and a measurement and calculation assembly. Multiple experimental rods 2 are arranged in a rod bundle flow channel array within the experimental tank 1, and the experimental rods 2 maintain the same torsion angle, accurately simulating the real flow channel environment of the cross-shaped torsion fuel assembly. During the cross-shaped torsion fuel assembly performance analysis experiment, deionized water is first introduced into the experimental tank 1 through the water supply circuit assembly 3. After the experimental tank 1 is filled with deionized water, the fluid recovery assembly 4 simultaneously recovers the flowing deionized water. At this time, the deionized water flows through the sub-channels between pairs of experimental rods 2. Then, the tracer in the tracer storage tank 51 is injected into the experimental tank through the inlet tube 52 at a quantity and location selected by the experimenter. Within the target flow channel area of ​​the barrel 1, the arrangement of one experimental rod 2 corresponding to the center of every four inlet tubes 52 ensures that the tracer acts on the sub-channels formed by adjacent experimental rods 2. After the tracer completes lateral mixing in the experimental barrel 1, the mixed solution is recovered and stored using all outlet tubes 62 and collection tanks 61. The measurement and calculation components detect the mixed solution in each collection tank 61 and calculate the concentration value of the tracer in each collection tank 61 based on the detection results. By selecting different numbers and positions of inlet tubes 52 and conducting multiple experiments, the mixing model of the central area and side wall area of ​​the cross-shaped torsion fuel assembly is clarified by quantitatively comparing the concentration distribution of sub-channels with different cross-sections. The mass balance relationship of all sub-channels is established in combination with the experimental boundary conditions, and the equivalent mixing coefficient of the fuel assembly is finally obtained by using the least squares method.

[0023] It is understandable that the multiple experimental rods 2 installed inside the experimental barrel 1 have the same torsion angle, which can improve the accuracy of the flow field simulation.

[0024] It is understandable that, such as Figure 5 , Figure 6 As shown, experimental rod 2 is a cross-shaped torsion experimental rod. Its cross-sectional geometry can be characterized by the rib radius, rib root radius, and connecting section length. This cross-shaped cross-section is periodically torsionally around the axis to form a torsion structure. The axial geometry of experimental rod 2 is defined by the helical pitch, which physically means the axial length corresponding to the cross-section completing a 360° torsion. The above-mentioned experimental rod 2 is manufactured using 3D printing technology, and its processing accuracy and surface finish meet the technical requirements of the mixing experiment. The two ends of experimental rod 2 are drilled and tapped to achieve overall fixation of experimental rod 2.

[0025] In one feasible embodiment, the experimental bucket 1 includes: The barrel body 11 has a first fixing member 12 and a second fixing member 13 respectively provided on the upper and lower sides. The first fixing member 12 includes a first positioning plate 121 and a first fixing rod 122. The first positioning plate 121 is located on the top of the barrel body 11. The first positioning plate 121 has a plurality of first fixing holes. The first fixing rod 122 is located in the first fixing holes. The second fixing member 13 includes a second positioning plate 131 and a second fixing rod 132. The second positioning plate 131 is disposed at the bottom of the barrel body 11. A plurality of second fixing holes are provided on the second positioning plate 131 at positions matching the first fixing hole. The second fixing rod 132 is disposed in the second fixing holes. The experimental rod 2 is disposed between the first positioning plate 121 and the second positioning plate 131, and the first fixing rod 122 and the second fixing rod 132 are connected to the experimental rod 2.

[0026] In this technical solution, the experimental barrel 1 includes a barrel body 11, and a first fixing member 12 and a second fixing member 13 assembled on its upper and lower sides. The first fixing member 12 and the second fixing member 13 are installed on both sides of the barrel body 11 to fix the experimental rod 2. The first fixing member 12 includes a first positioning plate 121 and a first fixing rod 122. The first fixing rod 122 is threadedly connected to the first end of the experimental rod 2 through a first fixing hole on the first positioning plate 121, thus fixing the experimental rod 2. The second fixing member 13 has a second positioning plate 131 symmetrically distributed above and below the first positioning plate 121. The second fixing hole on the second positioning plate 131 matches the position of the first fixing hole. The second fixing rod 132 is threadedly connected to the second end of the experimental rod 2 through the second fixing hole. The first fixing rod 122 and the second fixing rod 132 fix the experimental rod 2 to the first positioning plate 121 and the second positioning plate 131 from both ends, reducing the probability of the experimental rod 2 shifting or shaking due to fluid impact during the experiment, and improving the reliability of the experimental data.

[0027] It is understandable that, such as Figure 3 As shown, the first positioning plate 121 and the second positioning plate 131 are stainless steel plates with flange holes, and the plate thickness is 2.0 mm. Part of the stainless steel plate is hollowed out by laser cutting, and the unhollowed parts are shaped to match the cross-section of the experimental rod 2. A hole is drilled in the center of the hole for fixing the experimental rod 2.

[0028] In one feasible embodiment, it further includes: a first sealing plate 14, the first sealing plate 14 being disposed on the side of the first fixing member 12 away from the barrel body 11, the first sealing plate 14 having an outlet hole, and the outlet pipe 62 being disposed in the outlet hole and communicating with the inside of the barrel body 11. The second sealing plate 15 is disposed on the side of the second fixing member 13 away from the barrel body 11. The second sealing plate 15 has an inlet hole, and the inlet pipe 52 is disposed in the inlet hole and communicates with the inside of the barrel body 11.

[0029] In this technical solution, the experimental barrel 1 also includes a first sealing plate 14 and a second sealing plate 15. The first sealing plate 14 is assembled on the side of the first fixing member 12 away from the barrel body 11, and is used to seal and fix the top of the experimental barrel 1. The outlet hole opened on it provides an assembly channel for the outlet tube 62, so that the outlet tube 62 can pass through the outlet hole and communicate with the inside of the barrel body 11. The second sealing plate 15 is correspondingly arranged on the side of the second fixing member 13 away from the barrel body 11, and is used to seal and fix the bottom of the experimental barrel 1. The inlet hole on it is adapted to the inlet tube 52, so as to realize the communication between the inlet tube 52 and the inside of the barrel body 11. The first sealing plate 14 and the second sealing plate 15 can seal the upper and lower ports of the barrel body 11. On the one hand, it can prevent deionized water or tracer solution from leaking from the gap between the first fixing member 12 and the second fixing member 13 and the barrel body 11, ensuring the pressure stability and fluid closed loop of the experimental system, and avoiding flow field velocity and pressure deviation caused by leakage. On the other hand, it can block external dust and impurities from entering the inside of the barrel body 11, preventing impurities from contaminating the solution or interfering with the flow field state, and ensuring the accuracy of experimental data.

[0030] It is understandable that auxiliary sealing components such as sealing rings and sealing gaskets can be added between the outlet hole and the outlet tube 62, and between the inlet hole and the inlet tube 52, to ensure that there is no fluid leakage at the connection.

[0031] In one feasible embodiment, the water supply loop assembly 3 includes: Storage tank 31; The water supply pipeline 32 is provided with an inlet pipe on the tank body 11. The water supply pipeline 32 is located between the storage water tank 31 and the inlet pipe. The water supply pipeline 32 is provided with a first pump body 33, a first water supply mass flow meter 34 and a water supply control valve 35 in sequence.

[0032] In this technical solution, the water supply circuit assembly 3 includes a storage tank 31, a water supply pipeline 32, and a first pump body 33, a first water supply mass flow meter 34, and a water supply control valve 35 connected in series on the pipeline. The storage tank 31 is used to store deionized water, which can ensure a continuous and stable water supply during the experiment. The water supply pipeline 32 is used to connect the storage tank 31 and the tank body 11, which can transport deionized water into the tank body 11. During the experiment, the first pump body 33 serves as a power source and can output a stable pressure according to the experimental requirements to transport the deionized water in the storage tank 31 into the tank body 11. The first water supply mass flow meter 34 can monitor the mass flow rate in the water supply pipeline 32 in real time and provide feedback on the fluid transport parameters, so that the experimenters can keep track of the flow field supply status in real time and realize the supply of deionized water into the tank body 11.

[0033] In one feasible embodiment, the fluid recovery component 4 includes: Wastewater tank 41; A drain pipe 42 is provided on the tank body 11 and above the water inlet pipe. The drain pipe 42 is located between the wastewater tank 41 and the water outlet pipe. A drain control valve 43 is provided on the drain pipe 42.

[0034] In this technical solution, the fluid recovery component 4 includes a wastewater tank 41, a drainage pipe 42, and a drainage control valve 43, which realizes the collection of experimental fluids. The drainage control valve 43 ensures the stability of the flow field inside the tank body 11. During the entire experiment, in the initial water filling and venting stage, opening the drainage control valve 43 can quickly discharge non-condensable gases and initial gas-containing water inside the tank body 11. In the stable operation stage, by adjusting the opening of the drainage control valve 43, the drainage flow rate is matched with the water supply flow rate, maintaining the liquid level and pressure balance inside the tank body 11, and avoiding flow field disturbance caused by pressure fluctuations, which would affect the mixing state.

[0035] In one feasible embodiment, the tracer delivery component 5 further includes: A connecting pipe 53 is provided between the inlet pipe 52 and the tracer storage tank 51. A second pump body 54, a second mass flow meter 55 and a first control valve 56 are sequentially provided on the connecting pipe 53.

[0036] In this technical solution, the tracer delivery component 5 also includes a connecting pipe 53, on which a second pump body 54, a second mass flow meter 55, and a first control valve 56 are sequentially arranged. The connecting pipe 53 serves as a delivery channel between the tracer storage tank 51 and the inlet pipe 52, enabling the tracer to be delivered from the tracer storage tank 51 to the target injection position inside the experimental barrel 1. During the experiment, after the barrel body 11 is filled with deionized water and the flow rate supplied by the water supply pipe 32 is balanced with the flow rate discharged by the drain pipe 42, one or more inlet pipes 52 can be selected to deliver the tracer in the tracer storage tank 51 to the experimental barrel 1 through the connecting pipe 53, according to experimental requirements. The second mass flow meter 55 can monitor the delivery flow rate of the tracer in real time to ensure that the injection volume is the same as the flow rate supplied by the water supply pipe 32 and the flow rate discharged by the drain pipe 42, so as to achieve a mixed state between the tracer and deionized water in the experimental rod 2, providing a basis for subsequent experiments.

[0037] In one feasible embodiment, the tracer recovery component 6 further includes: A collection pipe 63 is provided between each of the collection tanks 61 and the corresponding outlet pipe 62, and a second control valve 64 is provided on the collection pipe 63.

[0038] In this technical solution, the tracer recovery assembly 6 also includes a collection pipeline 63 and a second control valve 64. The collection pipeline 63 is connected between each collection tank 61 and the corresponding outlet pipe 62. The second control valve 64 is correspondingly set on each collection pipeline 63. In the experiment, when the tracer is discharged from the outlet pipe 62 after being mixed in the flow field inside the experimental tank 1, all the second control valves 64 can be opened to realize the recovery of the mixed solution after mixing at all locations.

[0039] In one feasible embodiment, the measurement and calculation components include a conductivity meter, a temperature sensor, and a data processing module. The conductivity meter and the temperature sensor are used to measure the conductivity and temperature values ​​of the mixed solution in each of the collection tanks 61. The data processing module calculates the tracer concentration value in each of the collection tanks 61 based on the detected conductivity and temperature values.

[0040] In this technical solution, the measurement and calculation components include a conductivity meter, a temperature sensor, and a data processing module. The conductivity meter and temperature sensor are used to measure the conductivity and temperature of the mixed solution in each collection tank 61. The influence of ambient temperature changes on the conductivity measurement is offset by a temperature correction formula. The data processing module calculates the tracer concentration in each collection tank 61 using the conductivity-concentration relationship of potassium chloride solution at 25℃. Multiple experiments are conducted by selecting different numbers and positions of inlet tubes 52, and the mixing model of the central area and sidewall area of ​​the cross-shaped torsion fuel assembly is clarified by quantitatively comparing the concentration distribution of sub-channels with different cross-sections. The mass balance relationship of all sub-channels is established by combining the experimental boundary conditions, and the equivalent mixing coefficient of the fuel assembly is finally obtained by using the least squares method.

[0041] Understandably, each collection tank 61 is equipped with a conductivity meter and a temperature sensor to achieve real-time synchronous measurement.

[0042] In one feasible embodiment, the number of experimental rods 2 is 16, and the number of inlet tubes 52 and outlet tubes 62 are 25 each.

[0043] See also Figure 7 As shown in the embodiments of this application, a method for performance analysis of a cross-shaped torsion fuel assembly is also provided, which uses the above-described cross-shaped torsion fuel assembly performance analysis device and includes the following steps: S1. Start the first pump body 33 of the water supply circuit assembly 3, and deliver deionized water to the experimental tank 1 through the water supply pipeline 32, and control the mass flow rate in the water supply pipeline 32 within the target range. After the deionized water fills the experimental tank 1, it continues to flow for the target time to remove non-condensable gases in the experimental tank 1. During this period, the deionized water flowing out of the experimental tank 1 is discharged into the wastewater tank 41 through the drain pipeline 42.

[0044] In this technical solution, after the first pump 33 of the water supply loop assembly 3 is started, the first pump 33 can transport the deionized water in the storage tank 31 to the experimental barrel 1 along the water supply pipeline 32. At the same time, the flow rate data is monitored in real time by the first water supply mass flow meter 34 on the water supply pipeline 32. With the adjustment of the opening of the water supply control valve 35, the mass flow rate of the deionized water in the pipeline is strictly controlled within the target range required by the experiment, such as 50-5000 kg / (m²). To ensure the initial flow field meets the boundary conditions of the mixing experiment, after the deionized water fills the rod bundle channel of experimental tank 1, the deionized water is kept flowing continuously for the target time. This effectively removes residual non-condensable gases in experimental tank 1, ensuring the stability and uniformity of the flow field in subsequent mixing experiments. During this period, the gaseous deionized water flowing out of experimental tank 1 is discharged into wastewater tank 41 through drain pipe 42. After the venting is completed, the flow rate of drain pipe 42 is made the same as the flow rate of water supply pipe 32 according to the needs of subsequent experiments, maintaining the stability of the liquid level and pressure in experimental tank 1. S2. Select one or more of the inlet tubes 52 according to the experimental plan, open the first control valve 56 on the connecting pipe 53 at the selected location, and start the second pump body 54 to discharge the tracer in the tracer storage tank 51 into the experimental barrel 1 through the selected inlet tube 52. During this process, the mass flow rate in the connecting pipe 53 is kept the same as the mass flow rate in the water supply pipe 32.

[0045] In this technical solution, according to the experimental research requirements, one or more of the inlet pipes 52 are selected, and the first control valve 56 on the connecting pipe 53 at the selected location is opened accordingly. Then, the second pump body 54 is started, so that the tracer in the tracer storage tank 51 can be discharged into the experimental barrel 1 through the selected inlet pipe 52. During the entire injection process, the mass flow rate in the connecting pipe 53 must be kept consistent with the mass flow rate in the water supply pipe 32. This ensures that while injecting the tracer, local flow field disturbances caused by flow rate differences can be avoided, ensuring that the tracer is integrated into the main flow field of the coolant without interference, and truly simulating the natural mixing process in the sub-channel.

[0046] S3. After the tracer is injected and flows stably in the experimental barrel 1 for a certain period of time, the second control valve 64 on each of the collection pipes 63 is opened, and the mixed solution in the experimental barrel 1 at the target time is collected through the collection tank 61 corresponding to the outlet pipe 62.

[0047] In this technical solution, after the tracer is injected into the experimental tank 1 and flows stably for a certain period of time, it ensures that the tracer flows through different sub-channels with the main current of deionized water, truly reflecting the mixing pattern of the central and sidewall regions. The second control valve 64 on each collection pipe 63 is opened, and the mixed solution in the experimental tank 1 within the target time is collected through the collection tank 61 corresponding to the outlet pipe 62. This completely captures the mixed solution sample in each sub-channel, ensuring that subsequent concentration detection accurately corresponds to the mixing results of each sub-channel. Simultaneously, by collecting for the same amount of time, the sampling volume of each collection tank 61 is ensured to be consistent, providing standardized data for subsequent quantitative comparison of concentration distributions across different cross-sections and establishment of mass balance equations, further improving the accuracy and comparability of experimental results.

[0048] S4. The temperature and conductivity values ​​of the mixed solution in each of the collection tanks 61 are measured by the temperature sensor and conductivity meter of the measurement and calculation component. The data processing module calculates the tracer concentration value in each of the collection tanks 61 based on the detected conductivity value and temperature value, and quantitatively compares the concentration distribution of sub-channels at different cross-sections based on the concentration value data.

[0049] In this technical solution, the measurement and calculation components include a conductivity meter, a temperature sensor, and a data processing module. The conductivity meter and temperature sensor are used to measure the conductivity and temperature of the mixed solution in each collection tank 61. The influence of ambient temperature changes on the conductivity measurement is offset by a temperature correction formula. The data processing module calculates the tracer concentration in each collection tank 61 using the conductivity-concentration relationship of potassium chloride solution at 25℃. Multiple experiments are conducted by selecting different numbers and positions of inlet tubes 52, and the mixing model of the central area and sidewall area of ​​the cross-shaped torsion fuel assembly is clarified by quantitatively comparing the concentration distribution of sub-channels with different cross-sections. The mass balance relationship of all sub-channels is established by combining the experimental boundary conditions, and the equivalent mixing coefficient of the fuel assembly is finally obtained by using the least squares method.

[0050] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application. The above are merely preferred embodiments of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the protection scope of this application.

Claims

1. A performance analysis device for a cross-shaped twisted fuel assembly, characterized in that, include: Experimental barrel (1), the experimental barrel (1) is a hollow structure, and multiple experimental rods (2) are arranged at intervals along the axial direction in a rod bundle flow channel array, and all the experimental rods (2) have the same twist angle, and sub-channels are formed between adjacent experimental rods (2). Water supply circuit assembly (3), which is connected to the first end of the experimental tank (1) and is used to supply deionized water into the experimental tank (1); A fluid recovery assembly (4) is connected to the second end of the experimental tank (1) and is used to recover the deionized water flowing through the experimental tank (1); The tracer delivery assembly (5) includes a tracer storage box (51) and an inlet tube (52). Multiple inlet tubes (52) are disposed at the bottom of the experimental barrel (1). The tracer storage box (51) is connected to the inlet tubes (52), and an experimental rod (2) is disposed at the center of every four inlet tubes (52). The tracer recovery assembly (6) includes multiple collection tanks (61) and multiple outlet tubes (62). The outlet tubes (62) are located on the top of the experimental barrel (1) and are matched with the position of the inlet tubes (52). Each collection tank (61) is connected to the corresponding outlet tube (62) for recovering the mixed solution at the corresponding position of each inlet tube (52). A measurement and calculation component is used to detect the mixed solution in each collection tank (61) and calculate the concentration value of the tracer in each collection tank (61) based on the detection results; In this process, tracers are injected into the experimental container (1) by selecting different numbers and positions of the inlet tubes (52). After the tracers have completed lateral mixing in the experimental container (1), the mixed solution is introduced into the corresponding collection tank (61) through all the outlet tubes (62). The concentration value of the tracer in each collection tank (61) is accurately calculated by the measurement and calculation component. Based on the concentration value data, the concentration distribution of sub-channels in different cross-sections is quantitatively compared.

2. The performance analysis device for the cross-shaped twisted fuel assembly according to claim 1, characterized in that, The experimental container (1) includes: The barrel body (11) has a first fixing member (12) and a second fixing member (13) respectively provided on its upper and lower sides. The first fixing member (12) includes a first positioning plate (121) and a first fixing rod (122). The first positioning plate (121) is located on the top of the barrel body (11). The first positioning plate (121) has a plurality of first fixing holes. The first fixing rod (122) is located in the first fixing holes. The second fixing member (13) includes a second positioning plate (131) and a second fixing rod (132). The second positioning plate (131) is disposed at the bottom of the barrel body (11). A plurality of second fixing holes are provided on the second positioning plate (131) at the matching position of the first fixing hole. The second fixing rod (132) is disposed in the second fixing hole. The experimental rod (2) is positioned between the first positioning plate (121) and the second positioning plate (131), and the first fixing rod (122) and the second fixing rod (132) are connected to the experimental rod (2).

3. The performance analysis device for the cross-shaped twisted fuel assembly according to claim 2, characterized in that, Also includes: The first sealing plate (14) is disposed on the side of the first fixing member (12) away from the barrel body (11). The first sealing plate (14) has an outlet hole, and the outlet pipe (62) is disposed in the outlet hole and communicates with the inside of the barrel body (11). The second sealing plate (15) is disposed on the side of the second fixing member (13) away from the barrel body (11). The second sealing plate (15) has an inlet hole, and the inlet pipe (52) is disposed in the inlet hole and communicates with the barrel body (11).

4. The performance analysis device for the cross-shaped twisted fuel assembly according to claim 3, characterized in that, The water supply loop assembly (3) includes: Water storage tank (31); Water supply pipeline (32), the tank body (11) is provided with a water inlet pipe, the water supply pipeline (32) is located between the storage water tank (31) and the water inlet pipe, and the water supply pipeline (32) is provided with a first pump body (33), a first water supply mass flow meter (34) and a water supply control valve (35) in sequence.

5. The performance analysis device for the cross-shaped twisted fuel assembly according to claim 1, characterized in that, The fluid recovery assembly (4) includes: Wastewater tank (41); A drain pipe (42) is provided on the tank body (11) and above the water inlet pipe. The drain pipe (42) is located between the wastewater tank (41) and the water outlet pipe. A drain control valve (43) is provided on the drain pipe (42).

6. The performance analysis device for the cross-shaped twisted fuel assembly according to claim 5, characterized in that, The tracer delivery component (5) further includes: A connecting pipe (53) is provided between the inlet pipe (52) and the tracer storage tank (51). A second pump body (54), a second mass flow meter (55) and a first control valve (56) are sequentially provided on the connecting pipe (53).

7. The performance analysis device for the cross-shaped twisted fuel assembly according to claim 6, characterized in that, The tracer recovery assembly (6) also includes: A collection pipeline (63) is provided between each of the collection tanks (61) and the corresponding outlet pipe (62), and a second control valve (64) is provided on the collection pipeline (63).

8. The performance analysis device for the cross-shaped twisted fuel assembly according to claim 7, characterized in that, The measurement and calculation components include a conductivity meter, a temperature sensor and a data processing module. The conductivity meter and the temperature sensor are used to measure the conductivity and temperature of the mixed solution in each of the collection tanks (61). The data processing module calculates the tracer concentration value in each of the collection tanks (61) based on the detected conductivity value and temperature value.

9. The performance analysis device for the cross-shaped twisted fuel assembly according to claim 8, characterized in that, The number of experimental rods (2) is 16, and the number of inlet tubes (52) and outlet tubes (62) is 25 each.

10. A method for performance analysis of a cross-shaped twisted fuel assembly, characterized in that, The performance analysis apparatus for the cross-shaped torsion fuel assembly as described in any one of claims 1-9 includes the following steps: S1. Start the first pump (33) of the water supply circuit assembly (3) and deliver deionized water to the experimental tank (1) through the water supply pipeline (32). Control the mass flow rate in the water supply pipeline (32) within the target range. After the deionized water fills the experimental tank (1), continue to flow for the target time to remove the non-condensable gas in the experimental tank (1). During this period, the deionized water flowing out of the experimental tank (1) is discharged into the wastewater tank (41) through the drain pipeline (42). S2. Select one or more of the inlet tubes (52) according to the experimental plan, open the first control valve (56) on the connecting pipe (53) at the selected location, and start the second pump (54) to discharge the tracer in the tracer storage tank (51) into the experimental bucket (1) through the selected inlet tube (52). During this process, the mass flow rate in the connecting pipe (53) is the same as the mass flow rate in the water supply pipe (32). S3. After the tracer is injected and flows stably in the experimental barrel (1) for a certain period of time, open the second control valve (64) on each of the collection pipes (63) and collect the mixed solution in the experimental barrel (1) at the target time through the collection tank (61) corresponding to the outlet pipe (62). S4. The temperature and conductivity values ​​of the mixed solution in each of the collection tanks (61) are measured by the temperature sensor and conductivity meter of the measurement and calculation component. The data processing module calculates the tracer concentration value in each of the collection tanks (61) based on the detected conductivity value and temperature value, and quantitatively compares the sub-channel concentration distribution of different cross-sections based on the concentration value data.

Images