Method for measuring temperature of reactor core of heat pipe micro reactor

Abstract

The invention provides a method for measuring the temperature of a heat pipe micro-reactor core. The method comprises the following steps: modeling the heat pipe micro-reactor core to obtain a three-dimensional model of the core; simulating different heat pipe failure working conditions on the reactor core three-dimensional model to obtain a temperature field distribution rule of the reactor core; determining a plurality of matrix temperature measuring points according to the temperature field distribution rule; obtaining the temperature of the heat pipe micro-reactor core according to the temperatures of the plurality of matrix temperature measuring points; the step of determining the plurality of matrix temperature measuring points according to the temperature field distribution rule comprises the step of determining a plurality of candidate measuring point schemes according to the temperature field distribution rule, and each candidate measuring point scheme comprises a plurality of candidate measuring points; whether the candidate measuring point scheme meets a constraint condition or not is judged, if yes, candidate measuring points in the candidate measuring point scheme serve as matrix temperature measuring points, and the constraint condition is that for different heat pipe failure working conditions, before a matrix or a fuel rod reaches a temperature over-limit value, the matrix or the fuel rod is taken as matrix temperature measuring points; at least one candidate measuring point in the candidate measuring point scheme can monitor that the temperature of the candidate measuring point reaches the preset temperature within the preset time.

Description

Technical Field

[0001] The invention mainly relates to the technical field of nuclear reactors, and in particular to a method for measuring the core temperature of a heat pipe micro-reactor. Background Art

[0002] Compared with traditional pressurized water reactors, heat pipe micro-reactors are a new type of reactor. Heat pipe micro-reactors generally use all-solid cores and use heat pipes as passive heat extraction devices. The heat transfer path of the heat pipe micro-reactor is that the heat generated by the core fuel rods is transferred to the matrix through heat conduction, and then to the heat pipes, and then to the secondary circuit system or thermoelectric conversion device by the heat pipes. This is very different from the heat transfer path of traditional pressurized water reactor nuclear power plants, high temperature gas-cooled reactors and other reactors. In addition, due to the compact arrangement of the core of the solid-state heat pipe micro-reactor, the matrix is ​​in direct contact with the fuel rods and heat pipes, and there is almost no air gap. With current measurement technology, it is impossible to directly measure the temperature of the fuel rods in the core. The existing core temperature measurement method is not suitable for heat pipe micro-reactors. Summary of the invention

[0003] The present invention solves the problem that the temperature of fuel rods in a heat pipe micro-reactor core cannot be directly measured and proposes a heat pipe micro-reactor core temperature measurement method.

[0004] To solve the above technical problems, the present invention provides a method for measuring the core temperature of a heat pipe micro-reactor, comprising: modeling a heat pipe micro-reactor core to obtain a three-dimensional core model; simulating different heat pipe failure conditions on the three-dimensional core model to obtain a temperature field distribution law of the core; determining a plurality of substrate temperature measurement points according to the temperature field distribution law; obtaining the temperature of the heat pipe micro-reactor core according to the temperatures of the plurality of substrate temperature measurement points; wherein determining a plurality of substrate temperature measurement points according to the temperature field distribution law comprises: determining a plurality of candidate measurement point schemes according to the temperature field distribution law, each candidate measurement point scheme comprising a plurality of candidate measurement points; judging whether the candidate measurement point schemes satisfy a constraint condition, and if so, using the candidate measurement points in the candidate measurement point schemes as the substrate temperature measurement points, the constraint condition being that for different heat pipe failure conditions, before the substrate or the fuel rod reaches an over-limit temperature value, at least one candidate measurement point in the candidate measurement point scheme can monitor that the temperature of the candidate measurement point reaches a preset temperature within a preset time.

[0005] Optionally, the fuel assembly of the heat pipe micro-reactor core is a regular n-gon, and the fuel rods and heat pipes of the fuel assembly are cross-arranged.

[0006] Optionally, determining a plurality of substrate temperature measurement points according to the temperature field distribution law includes determining that the number of the substrate temperature measurement points is n, each substrate temperature measurement point is located on an end surface of the substrate, and the n substrate temperature measurement points are respectively located on respective lines connecting the center of the fuel assembly and the n vertices of the regular n-gon.

[0007] Optionally, determining a plurality of substrate temperature measuring points according to the temperature field distribution law includes determining that the number of the substrate temperature measuring points is n / 2, each substrate temperature measuring point is located on an end surface of the substrate, the n / 2 substrate temperature measuring points are respectively located on respective lines connecting the center of the fuel assembly and n / 2 vertices of the regular n-gon, and the interval angle of each connecting line is 720 / n°.

[0008] Optionally, the fuel assembly includes n reserved holes located at the vertices of the regular n-gon, and determining multiple substrate temperature measuring points according to the temperature field distribution law includes determining that the number of the substrate temperature measuring points is n, and each substrate temperature measuring point is located at an axial center of the reserved hole that is biased toward the evaporation section of the heat pipe.

[0009] Optionally, the fuel assembly includes n reserved holes located at the vertices of the regular n-gon, and determining a plurality of substrate temperature measuring points according to the temperature field distribution law includes determining that the number of the substrate temperature measuring points is n / 2, and the axial centers of n / 2 of the n reserved holes are respectively arranged at positions biased toward the evaporation section of the heat pipe, and the interval angle between adjacent substrate temperature measuring points is 720 / n°.

[0010] Optionally, simulating different heat pipe failure conditions on the three-dimensional core model includes: simulating different heat pipe failure positions and different numbers of heat pipe failures on the three-dimensional core model.

[0011] Optionally, modeling the heat pipe micro-reactor core to obtain a three-dimensional core model includes: constructing multiple candidate models according to the structure of the heat pipe micro-reactor core, the multiple candidate models including a single-component model with a cover, a single-component model without a cover, a multi-component model with a cover, and a multi-component model without a cover; each candidate model is operated in a steady-state condition to obtain a steady-state temperature field distribution of each candidate model; comparing the steady-state temperature field distributions of all candidate models, if the temperature distribution cloud of the highest temperature section of the substrate in all steady-state temperature field distributions is Figure 1 The temperature distribution of the two ends of the substrate is consistent Figure 1 If the single component model without cover plate is consistent, the single component model without cover plate is selected as the core three-dimensional model.

[0012] Optionally, obtaining the temperature of the heat pipe micro-stack core according to the temperatures of the multiple substrate temperature measurement points includes: taking the highest temperature among the multiple substrate temperature measurement points as the temperature of the heat pipe micro-stack core.

[0013] Optionally, it also includes: verifying the rationality of the positions of the multiple substrate temperature measurement points, including: adding the multiple substrate temperature measurement points to the core three-dimensional model; inputting typical accident conditions into the core three-dimensional model, if the core three-dimensional model triggers a protection signal, it indicates that the positions of the multiple substrate temperature measurement points are reasonable.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] The present application proposes a method for measuring the core temperature of a heat pipe micro-reactor, which indirectly measures the core temperature of the heat pipe micro-reactor by measuring the temperature of the substrate; further, multiple substrate temperature measurement points are determined according to whether the temperature field distribution law meets the constraint conditions, ensuring that the substrate and fuel rod temperature anomalies can be monitored under different heat pipe failure positions and numbers, and under the premise of ensuring safety, the minimum number of measurement points is guaranteed to improve economic efficiency. The heat pipe micro-reactor core temperature measurement method of the present application is effective, simple and highly accurate, and can be widely used in heat pipe micro-reactor design, protection signal setting value determination and accident safety evaluation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are included to provide a further understanding of the present application. They are included and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and together with the present specification serve to explain the principles of the present invention. In the accompanying drawings:

[0017] Figure 1 The figure is a flow chart of a method for measuring the core temperature of a heat pipe micro-reactor according to an embodiment of the present invention.

[0018] Figure 2 Schematic diagram of the structure of a heat pipe micro-reactor core according to an embodiment of the present invention.

[0019] Figure 3 yes Figure 2 Left view of a single fuel assembly in the core of a heat pipe microreactor.

[0020] Figure 4 yes Figure 1 Flow chart of an embodiment of step S11 in FIG.

[0021] Figure 5 yes Figure 1 Flow chart of an embodiment of step S13 in FIG.

[0022] Figure 6 yes Figure 2 Front view of a single fuel assembly in the core of a heat pipe microreactor.

[0023] Figure 7 yes Figure 1 Flow chart of the heat pipe micro-reactor core temperature measurement method of the optimized embodiment. DETAILED DESCRIPTION

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0025] The core of the solid-state heat pipe micro-reactor is compactly arranged, and the matrix is ​​in direct contact with the fuel rods and heat pipes with almost no air gap. With current measurement technology, the temperature of the fuel rod core and cladding of the fuel rod cannot be directly monitored. Among them, the matrix is ​​an important component for carrying fuel rods and heat pipes, and it plays an important role in the heat transfer of the core. Therefore, an indirect measurement method can be used to measure the temperature of the matrix or the temperature of the heat pipe as the temperature of the core to monitor the safety of the core. However, there are many challenges to overcome in arranging temperature measurement points on the heat pipes. Due to the large number of heat pipes, the cost and construction difficulty of arranging all the measurement points are high. If only some heat pipes are selected for temperature measurement, the failure of the heat pipes where the measurement points are not arranged cannot be monitored in time. Therefore, it is prioritized to monitor the temperature of the matrix to ensure the safety of the core.

[0026] In addition, it is also difficult to arrange temperature measurement points inside the substrate to monitor the maximum temperature of the substrate. This is because the arrangement of the holes in the solid-state heat pipe micro-stack substrate is too compact, the hole bridges between the substrate holes are small, and the measuring device (thermocouple) drills holes from the end of the substrate or the side of the substrate, and it is impossible to align the measurement points with the hole bridges. Therefore, temperature measurement points can only be arranged on the end face of the substrate or the reserved holes of the substrate.

[0027] Figure 1 FIG. 1 is a flow chart of a method for measuring the core temperature of a heat pipe micro-reactor according to an embodiment of the present invention. Figure 1 As shown, the heat pipe micro-reactor core temperature measurement method 100 includes the following steps:

[0028] Step S11: Modeling the heat pipe micro-reactor core to obtain a three-dimensional core model.

[0029] Figure 2 Schematic diagram of the structure of a heat pipe micro-reactor core according to an embodiment of the present invention. Figure 3 yes Figure 2 Left side view of a single fuel assembly in the core of a heat pipe microreactor. Figure 2 As shown, the heat pipe micro-reactor core 200 includes a plurality of fuel assemblies 1, a safety shutdown rod 2, a drum 3 and a reflector 4. Figure 3 As shown, the fuel assembly 1 includes a fuel rod 6, a substrate 7 and a heat pipe 8. The substrate 7 is provided with a plurality of through reserved holes, and the fuel rod 6 and the heat pipe 8 are cross-inserted into the reserved holes of the substrate 7. The substrate 7 includes an end face 71 and a cover plate 72. Figure 4 yes Figure 1Flow chart of step S11 in an embodiment. Figure 4 As shown, the heat pipe micro-reactor core is modeled according to the structure of the heat pipe micro-reactor core to obtain a three-dimensional core model including:

[0030] Step S111: Use three-dimensional fluid simulation analysis software (such as ANSYS Workbench / Star-CCM+) to model the main components of the heat pipe micro-reactor core to obtain multiple candidate models. The main components of the heat pipe micro-reactor core include but are not limited to fuel assemblies, safety shutdown rods, drums and reflective layers. Further, according to a single fuel assembly, multiple fuel assemblies, a substrate including a cover plate, and a substrate excluding a cover plate, a single component with a cover plate model, a single component without a cover plate model, a multi-component with a cover plate model, and a multi-component without a cover plate model are respectively established. The single component with a cover plate model, the single component without a cover plate model, the multi-component with a cover plate model, and the multi-component without a cover plate model are all used as candidate models.

[0031] Step S112: Each candidate model is operated in a steady-state condition to obtain the steady-state temperature field distribution of each candidate model. The temperature field is the collection of temperatures at each point in the material system, which is a function of time and space coordinates. According to whether it is stable or not, there are two major categories: steady-state temperature field and transient temperature field. The former does not change with time; the latter must clearly indicate at which moment it occurs to be meaningful.

[0032] Step S113: Compare the steady-state temperature field distributions of all candidate models. If the temperature distribution cloud of the highest temperature section of the matrix in all steady-state temperature field distributions is Figure 1 The temperature distribution of the two ends of the substrate is consistent Figure 1 If they are consistent, the single-component model without a cover is taken as the three-dimensional core model. In short, if all candidate models can obtain a steady-state temperature field distribution that meets the requirements, the single-component model without a cover with high computational efficiency and low cost is preferably considered as the three-dimensional core model. If they are inconsistent, the steady-state temperature field distribution of the multi-component model with a cover is taken as the standard, and the steady-state temperature field distribution of other candidate models is compared with the standard. If the temperature distribution cloud map of the highest temperature section of the matrix in the steady-state temperature field distribution of other candidate models is consistent with the standard and the temperature distribution cloud map of the two end faces of the matrix is ​​consistent with the standard, the candidate models are selected as the three-dimensional core model in the following order, which includes: single-component model with a cover>multi-component model without a cover>multi-component model with a cover.

[0033] In some embodiments, in addition to satisfying the temperature distribution cloud of the highest temperature section of the substrate in all steady-state temperature field distributions Figure 1 The temperature distribution of the two ends of the substrate is consistent Figure 1In addition, it is also necessary to meet the conditions that the temperature difference between the two end surfaces of the substrate is less than the preset value, the temperature difference of the highest temperature of the substrate is less than the preset value, and the temperature difference of the lowest temperature of the substrate is less than the preset value. When all conditions are met, the single-component cover-free model is converted into a core three-dimensional model.

[0034] Step S12: simulating different heat pipe failure conditions on the core three-dimensional model to obtain the temperature field distribution law of the core.

[0035] Among them, different heat pipe failure conditions refer to different heat pipe failure positions and different heat pipe failure numbers. Different heat pipe failure positions and different heat pipe failure numbers are simulated on the core three-dimensional model. Specifically, the heat pipe failures at different positions and different numbers are matrixed on the core three-dimensional model obtained in step S11, and sensitivity accident analysis is performed on all heat pipe failure conditions to obtain the temperature field distribution law of the core. The temperature field distribution law reflects the distribution of temperature in space and time.

[0036] Step S13: determining a plurality of substrate temperature measurement points according to the temperature field distribution law.

[0037] Figure 5 yes Figure 1 Flow chart of step S13 in an embodiment. Figure 5 As shown, according to the temperature field distribution law, multiple substrate temperature measurement points are determined, including:

[0038] Step S131: Determine multiple candidate measuring point schemes according to the temperature field distribution law of different heat pipe failure numbers and failure position accidents, and each candidate measuring point scheme includes multiple candidate measuring points. Exemplarily, candidate measuring point scheme 1 includes six candidate measuring points, and all of the six candidate measuring points are located on the end surface of the substrate. Candidate measuring point scheme 2 includes six candidate measuring points, and all of the six candidate measuring points are located in the reserved holes of the substrate. Candidate measuring point scheme 3 includes three candidate measuring points, and all of the three candidate measuring points are located on the end surface of the substrate.

[0039] Step S132: Determine whether the candidate measurement point scheme meets the constraint condition. If so, the candidate measurement point in the candidate measurement point scheme is used as the substrate temperature measurement point. The constraint condition is that for different heat pipe failure conditions, before the substrate or fuel rod reaches the temperature limit value, at least one candidate measurement point in the candidate measurement point scheme can monitor that the temperature of the candidate measurement point reaches the preset temperature within a preset time. For example, before the substrate or fuel rod reaches the temperature limit value, at least one candidate measurement point can monitor that the temperature of the candidate measurement point rises by 20°C within one minute. In short, at least one candidate measurement point can monitor that the temperature of the candidate measurement point rises significantly in a short period of time.

[0040] The above can be understood as finding a suitable position on the substrate to arrange the temperature measuring points, so that for different heat pipe failure conditions, the measuring point scheme can monitor the obvious rise in the substrate measuring point temperature before the substrate or fuel rod reaches the temperature limit. This ensures that under different heat pipe failure positions and numbers, the substrate or fuel rod temperature anomalies can be monitored.

[0041] Figure 6 yes Figure 2 Front view of a single fuel assembly in the core of a heat pipe microreactor. Figure 6 As shown, the fuel assembly 1 is a regular hexagon, and the fuel assembly 1 includes a fuel rod 6, a substrate 7 and a heat pipe 8. The substrate 7 includes a honeycomb-shaped reserved hole. The fuel rod 6 and the heat pipe 8 are cross-inserted into the reserved holes of the substrate 7. In some embodiments, the reserved holes (reserved holes 5) at the vertices of the regular hexagon of the substrate 7 are not used to place the fuel rod 6 or the heat pipe 8, but are used to place the substrate temperature measurement points.

[0042] The following is the corresponding Figure 6 Example of setting the matrix temperature measuring point in the fuel assembly:

[0043] In the first embodiment, a total of six substrate temperature measuring points 9 are included, which are respectively located on the lines connecting the center of the fuel assembly and the six vertices of the regular hexagon. Each substrate temperature measuring point 9 is located on the end surface of the substrate 7, and the reserved holes 5 are used to place the heat pipes 8.

[0044] In the second embodiment, a total of three substrate temperature measuring points 9 are included, which are respectively located on the lines connecting the center of the fuel assembly and the three vertices of the regular hexagon, and the interval angle of each line is 120°. In other words, three substrate temperature measuring points 9 that are not adjacent to each other are selected from the six substrate temperature measuring points 9. Each substrate temperature measuring point 9 is located on the end surface of the substrate 7, and the reserved hole 5 is used to place the heat pipe 8.

[0045] In the third embodiment, there are six substrate temperature measuring points in total, which are respectively located in six reserved holes 5. Specifically, each substrate temperature measuring point is located at the axial center of the reserved hole 5, which is biased towards the evaporation section of the heat pipe, that is, the substrate reserved hole temperature measuring point 10.

[0046] In the fourth embodiment, a total of three substrate temperature measuring points are included, which are respectively set in three of the six reserved holes 5, and the interval angle between adjacent substrate temperature measuring points is 120°. In other words, three non-adjacent reserved holes are selected from the six reserved holes 5 for placing the substrate temperature measuring points.

[0047] In some embodiments, the constraint condition is that for different heat pipe failure conditions, before the substrate or the fuel rod reaches the temperature limit value, at least one candidate measuring point in the candidate measuring point scheme can monitor that the temperature of the candidate measuring point can reach the preset temperature within the preset time, and can avoid false triggering due to temperature measurement uncertainty by setting a reasonable set value.

[0048] Step S14: obtaining the temperature of the heat pipe micro-reactor core according to the temperatures of a plurality of substrate temperature measurement points.

[0049] Optionally, the highest temperature among the multiple substrate temperature measurement points is used as the core temperature of the heat pipe micro-reactor.

[0050] Figure 7 yes Figure 1 Flow chart of the heat pipe micro-reactor core temperature measurement method of the optimized embodiment. Figure 7 As shown, the heat pipe micro-reactor core temperature measurement method 700 also includes:

[0051] Step S15: verifying the rationality of the positions of the multiple substrate temperature measurement points.

[0052] Optionally, multiple substrate temperature measurement points are added to the core three-dimensional model, and typical accident conditions are input into the updated core three-dimensional model. If the core three-dimensional model triggers a protection signal, it indicates that the positions of multiple substrate temperature measurement points are reasonable. If the positions of multiple substrate temperature measurement points are unreasonable, enter step S13 to redetermine multiple substrate temperature measurement points. Among them, typical accident conditions include but are not limited to accident conditions such as power increase and failure of multiple heat pipes. The protection signal is used to trigger rapid shutdown and the use of a dedicated residual heat removal system. The present application performs transient analysis iterative optimization verification on typical key accidents such as power increase and failure of multiple heat pipes. The rationality of the arrangement of substrate temperature measurement points is verified by studying the feasibility of the measurement point location and the characterization of the temperature at the measurement point location, thereby quickly shutting down the reactor and putting into use a dedicated residual heat removal system to ensure that the accident safety criteria do not exceed the limit value, the accident can be effectively alleviated, and the safety of the heat pipe micro-reactor is ensured.

[0053] The present application proposes a method for measuring the core temperature of a heat pipe micro-reactor, which indirectly measures the core temperature of the heat pipe micro-reactor by measuring the temperature of the substrate; further, multiple substrate temperature measurement points are determined according to whether the temperature field distribution law meets the constraint conditions, ensuring that the substrate and fuel rod temperature anomalies can be monitored under different heat pipe failure positions and numbers, and under the premise of ensuring safety, the minimum number of measurement points is guaranteed to improve economic efficiency. The heat pipe micro-reactor core temperature measurement method of the present application is effective, simple and highly accurate, and can be widely used in heat pipe micro-reactor design, protection signal setting value determination and accident safety evaluation.

[0054] The basic concepts have been described above. Obviously, for those skilled in the art, the above invention disclosure is only used as an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0055] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0056] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0057] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0058] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0059] A computer-readable medium may include a propagated data signal containing computer program code, such as in baseband or as part of a carrier wave. The propagated signal may have a variety of manifestations, including electromagnetic, optical, etc., or a suitable combination. A computer-readable medium may be any computer-readable medium other than a computer-readable storage medium, which may be connected to an instruction execution system, device or apparatus to communicate, propagate or transmit a program for use. The program code on the computer-readable medium may be propagated via any suitable medium, including radio, cable, fiber optic cable, radio frequency signal, or similar medium, or any combination of the above mediums.

[0060] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more embodiments of the invention, in the above description of the embodiments of this application, multiple features are sometimes combined into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0061] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values ​​is as accurate as possible within the feasible range.

[0062] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions may be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the essential spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A method for measuring the core temperature of a heat pipe micro-reactor, characterized in that: include: Model the heat pipe micro-reactor core to obtain a three-dimensional core model; Simulating different heat pipe failure conditions on the three-dimensional core model to obtain the temperature field distribution law of the core; Determine a plurality of substrate temperature measurement points according to the temperature field distribution law; Obtaining the temperature of the heat pipe micro-reactor core according to the temperatures of the plurality of substrate temperature measurement points; Among them, determining multiple substrate temperature measurement points according to the temperature field distribution law includes: determining multiple candidate measurement point schemes according to the temperature field distribution law, each candidate measurement point scheme includes multiple candidate measurement points; judging whether the candidate measurement point scheme satisfies a constraint condition, and if so, using the candidate measurement points in the candidate measurement point scheme as the substrate temperature measurement points, and the constraint condition is that for different heat pipe failure conditions, before the substrate or the fuel rod reaches an over-limit temperature, at least one candidate measurement point in the candidate measurement point scheme can monitor that the temperature of the candidate measurement point reaches a preset temperature within a preset time.

2. The method for measuring core temperature according to claim 1, characterized in that: The fuel assembly of the heat pipe micro-reactor core is a regular n-gon, where n is an even number greater than or equal to 4, and the fuel rods and heat pipes of the fuel assembly are cross-arranged.

3. The method for measuring core temperature according to claim 2, characterized in that: Determining a plurality of substrate temperature measurement points according to the temperature field distribution law includes determining that the number of the substrate temperature measurement points is n, each substrate temperature measurement point is located on an end surface of the substrate, and the n substrate temperature measurement points are respectively located on respective lines connecting the center of the fuel assembly and the n vertices of the regular n-gon.

4. The method for measuring core temperature according to claim 2, characterized in that: Determining a plurality of substrate temperature measuring points according to the temperature field distribution law includes determining that the number of the substrate temperature measuring points is n / 2, each substrate temperature measuring point is located on an end surface of the substrate, the n / 2 substrate temperature measuring points are respectively located on respective lines connecting the center of the fuel assembly and the n / 2 vertices of the regular n-gon, and the interval angle of each connecting line is 720 / n°.

5. The method for measuring core temperature according to claim 2, characterized in that: The fuel assembly includes n reserved holes located at the vertices of the regular n-gon, and determining multiple substrate temperature measuring points according to the temperature field distribution law includes determining that the number of the substrate temperature measuring points is n, and each substrate temperature measuring point is located at a position in the reserved hole whose axial center is biased toward the evaporation section of the heat pipe.

6. The method for measuring core temperature according to claim 2, characterized in that: The fuel assembly includes n reserved holes located at the vertices of the regular n-gon, and determining a plurality of substrate temperature measuring points according to the temperature field distribution law includes determining that the number of the substrate temperature measuring points is n / 2, and the axial centers of n / 2 of the n reserved holes are respectively arranged at positions biased toward the evaporation section of the heat pipe, and the interval angle of adjacent substrate temperature measuring points is 720 / n°.

7. The method for measuring core temperature according to claim 1, characterized in that: Simulating different heat pipe failure conditions on the three-dimensional core model includes: simulating different heat pipe failure positions and different numbers of heat pipe failures on the three-dimensional core model.

8. The method for measuring core temperature according to claim 1, characterized in that: Modeling the heat pipe micro-reactor core to obtain a three-dimensional core model includes: Constructing a plurality of candidate models according to the structure of the heat pipe micro-reactor core, wherein the plurality of candidate models include a single-component model with a cover plate, a single-component model without a cover plate, a multi-component model with a cover plate, and a multi-component model without a cover plate; Each candidate model is operated in a steady-state condition to obtain the steady-state temperature field distribution of each candidate model; By comparing the steady-state temperature field distributions of all candidate models, if the temperature distribution cloud diagrams of the highest temperature cross section of the substrate and the temperature distribution cloud diagrams of the two end surfaces of the substrate are consistent in all steady-state temperature field distributions, the single-component model without a cover plate is selected as the core three-dimensional model.

9. The method for measuring core temperature according to claim 1, characterized in that: Obtaining the temperature of the heat pipe micro-stack core according to the temperatures of the plurality of substrate temperature measurement points includes: taking the highest temperature among the plurality of substrate temperature measurement points as the temperature of the heat pipe micro-stack core.

10. The method for measuring core temperature according to claim 1, characterized in that: Also includes: Verifying the rationality of the positions of the plurality of substrate temperature measurement points includes: Adding the plurality of substrate temperature measurement points to the core three-dimensional model; A typical accident condition is input into the core three-dimensional model. If the core three-dimensional model triggers a protection signal, it indicates that the positions of the multiple substrate temperature measurement points are reasonable.

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