Reactor starting method and system based on neutron generator
By using a neutron generator in the reactor to replace the radioactive neutron source, the safety hazards and uncontrollable problems of traditional methods are solved, and the controllability of neutron production and the safety improvement of the reactor startup.
Patent Information
- Application Number
- CN202411393881.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-08
- Publication Date
- 2025-01-21
- Estimated Expiration
- 2044-10-08
AI Technical Summary
Traditionally, the use of radioactive neutron sources to achieve reactor startup has problems such as safety hazards, uncontrollability and limited application scope.
Use a neutron generator to replace the traditional radioactor neutron source. The theoretical model is established through the physical computing program of the reactor. The state of neutron production.
Eliminate the inherent risk of radioactive neutron sources, realize the start -stop controllability and strength adjustability of neutron, optimize the physical startup process of the reactor, improve the safety performance of the core, and reduce the cost of the equipment.
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Figure CN119337051A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of nuclear power technology, and specifically to a reactor startup method and system based on a neutron generator, which utilizes a neutron generator to replace a traditional radioactive neutron source and is applied to a reactor startup process. The method and system are applicable to various solid, liquid and gas research reactors, and are particularly applicable to critical devices. Background Art
[0002] During the reactor startup process, the various materials in the reactor can be combined in certain specific ways to gradually increase the number of neutrons produced in the reactor or gradually reduce the number of neutrons lost, so that the number of neutrons produced is equal to the number of neutrons lost, that is, to achieve k eff =1 or ρ=0.
[0003] During the initial startup of research reactors such as critical devices, the "neutron count inverse extrapolation method" is used to gradually raise the control rods to approach criticality. Before raising the control rods, a radioactive neutron source needs to be added to the reactor. When raising the control rods to extrapolate criticality, first raise a control rod to height H1 and record the neutron detector count rate N1, then raise a control rod to height H2 and record the neutron detector count rate N2. Based on the two neutron count rates and the height difference of the control rods, it can be extrapolated that the reactivity △ρ needs to be added to make the core reach criticality. Then, the next step is to add reactivity according to the "1 / 2 principle", that is, by raising the subsequent control rods to introduce a reactivity equivalent of △ρ / 2, and after repeated extrapolation operations, the core k can be made critical. eff When it reaches 0.996, the neutron source is removed from the reactor and the control rods are fine-tuned to make the core reach criticality, thus completing the reactor startup operation.
[0004] The reactor arranges nuclear fuel, control rods, poison rods, etc. according to certain rules. Nuclear fuel is mainly composed of fissile nuclides and fissile nuclides. The newly arranged reactor is in a deep subcritical state. It is necessary to introduce positive reactivity to the reactor by lifting the control rods to a certain extent before sufficient neutron signals can be generated for neutron detectors to identify. For newly arranged reactors, since the critical rod position of the control rods is unknown, the control rods cannot be lifted blindly.
[0005] Before lifting the control rods, it is necessary to add a start-up neutron source, which plays a role in "igniting" the reactor. The neutron detector can collect the change trend of the neutron signal emitted by the neutron source after passing through the reactor, and then use the back-end neutron counting measurement device (common neutron counting measurement devices include start-up neutron counting devices, neutron counting monitoring devices, etc.) to analyze and process the change trend of the above neutron signal to know the current state of the reactor. Under the condition of effective monitoring of the reactor state, the control rods are gradually lifted to make the reactor transition from the subcritical state to the critical state, and the reactor startup operation is realized. At this time, the number of neutrons produced by the reactor is equal to the number of neutrons destroyed.
[0006] Different reactors have different requirements for the strength of the startup neutron source. Generally, the strength of the startup neutron source is between 1 and 5 Ci. It is generally required that the counting rate of neutrons emitted by the startup neutron source passing through the core and reaching the neutron detector should be no less than 0.5 cps.
[0007] However, the high radioactivity of radioactive neutron sources can pose a safety threat to relevant operators; radioactive neutron sources will continuously emit rays, the neutron source intensity is uncontrollable, and there are great radiation safety risks; their transfer and installation processes are complicated and involve cumbersome management approvals; they can usually only be used in a specific reactor; if a fault or abnormality occurs or the performance does not meet the requirements, the neutron source can only be replaced, which is costly. Summary of the invention
[0008] In order to solve the problems existing in the traditional use of radioactive neutron sources to start the reactor, the present application proposes a reactor startup method and system based on a neutron generator. By adopting a neutron generator to start the reactor, the present application can eliminate the need to configure a traditional radioactive nuclide neutron source inside or near the reactor core, thereby eliminating the inherent risks of radioactive neutron sources. At the same time, since the neutrons generated by the neutron generator are controllable in start and stop and the intensity is adjustable, it is more conducive to optimizing the physical startup process of the reactor, thereby optimizing the layout of the reactor core while improving the safety performance of the core.
[0009] This application is implemented through the following technical solutions:
[0010] A reactor startup method based on a neutron generator, the reactor startup method comprising:
[0011] Use reactor physics calculation program to establish reactor theoretical model and conduct model verification;
[0012] The neutron yield of the neutron generator that meets the reactor startup requirements is determined by using a verified reactor theoretical model to count the neutrons generated by the neutron generator at the neutron detector after the neutrons pass through the core;
[0013] A neutron generator with a neutron yield that meets the reactor startup requirements is used to replace the reactor startup neutron source. Before the control rod is lifted during the reactor startup process, the neutron generator is turned on and maintained in a stable neutron yield emission state to perform the reactor startup operation.
[0014] In some embodiments, the use of a reactor physics calculation program to establish a reactor theoretical model specifically includes:
[0015] Using the Monte Carlo-based reactor physics calculation program, the reactor core, neutron detector, and neutron generator are modeled in detail from the inside out and in a step-by-step manner. During the modeling process, all control rods are set to move freely up and down.
[0016] In some embodiments, the model verification specifically includes:
[0017] The reactor theoretical model is calibrated and verified using a plurality of critical rod position measured values, and the calibration and verification conditions satisfy that the deviation between the measured value and the calculated value does not exceed a preset value.
[0018] In some embodiments, the neutron yield of the neutron generator that meets the reactor startup requirements is specifically:
[0019] The counting rate of the neutrons generated by the neutron generator at the neutron detector after passing through the core is generally not less than 0.5 cps.
[0020] In some embodiments, the maximum neutron yield of the neutron generator is generally higher than 1×10 9 n / s, and the neutron yield of the neutron generator can be freely adjusted between 0 and the maximum neutron yield.
[0021] In some embodiments, the reactor startup operation specifically includes:
[0022] Completing the installation and commissioning of the neutron generator outside the core;
[0023] After the neutron generator is installed, the neutron yield of the neutron generator is adjusted to a numerically calculated value and maintained in a stable neutron yield emission state, ensuring that the measured count rate of the rear neutron detector is greater than 0.5 cps;
[0024] Reactivity is added according to the 1 / 2 principle, and rod lifting and extrapolation experiments are carried out to bring the core to a critical state.
[0025] In some embodiments, the installation and commissioning of the neutron generator outside the core specifically includes:
[0026] The neutron generator and the neutron detector are respectively located on two opposite sides of the core, and the neutron generator is arranged outside the reactor barrel. The target nuclear component of the neutron generator, the core and the center of the neutron detector are arranged in a collinear manner.
[0027] In some embodiments, the rod lifting and extrapolation experiment specifically includes:
[0028] Determine the core critical rod position based on the measured value;
[0029] According to the core critical rod position, the extrapolation operation is repeated many times according to the 1 / 2 principle to make the core k eff It reaches 0.996, at which point the neutron generator is cut off;
[0030] Fine-tune the control rods to bring the core to criticality.
[0031] In some embodiments, the neutron generator is a device that generates a neutron beam through the effect of particle bombardment of a target nucleus.
[0032] On the other hand, the present application proposes a reactor startup system based on a neutron generator, the reactor startup system comprising:
[0033] A model building module, wherein the model building module is configured to: establish a reactor theoretical model using a reactor physics calculation program and perform model verification;
[0034] A numerical calculation module, wherein the numerical calculation module is configured to: use a verified reactor theoretical model to count the counting rate of neutrons generated by the neutron generator at the neutron detector after the neutrons pass through the core, and determine the neutron yield of the neutron generator that meets the reactor startup requirements;
[0035] And, a start-up module, the start-up module is configured to: use a neutron generator with a neutron yield that meets the reactor startup requirement to replace the start-up neutron source, and before lifting the control rod during the reactor startup process, turn on the neutron generator and maintain it in a stable neutron yield emission state to perform the reactor startup operation.
[0036] The present application proposes a reactor startup method and system based on a neutron generator, which uses a neutron generator to replace a traditional radionuclide neutron source, thereby eliminating the inherent risks of the radionuclide neutron source (such as the adverse effects of high radioactivity on personnel, etc.); at the same time, since the neutrons generated by the neutron generator are controllable in start and stop and the intensity is adjustable, it is more conducive to optimizing the physical startup process of the reactor, thereby optimizing the layout of the reactor core while improving the safety performance of the core;
[0037] The reactor startup method and system based on a neutron generator proposed in the present application are compared with the radionuclide neutron source which is uncontrollable and can only be applied to specific reactors. Once a failure or other situation occurs, the radionuclide neutron source can only be replaced. The neutron generator used in the present application has the advantages of generating monoenergetic neutrons, controllable yield, mobility, and reusability, which can greatly reduce costs and has great economic value.
[0038] The present application proposes a reactor startup method and system based on a neutron generator, which has a wide range of applications and can be applied to various types of solid, liquid and gas research reactors, and is particularly suitable for critical devices. BRIEF DESCRIPTION OF THE DRAWINGS
[0039] The drawings described herein are used to provide a further understanding of the embodiments of the present application, constitute a part of the present application, and do not constitute a limitation on the embodiments of the present application. In the drawings:
[0040] Figure 1 This is a schematic diagram of the structure of a neutron generator according to an embodiment of the present application;
[0041] Figure 2 This is a flow chart of a reactor startup method according to an embodiment of the present application;
[0042] Figure 3 A side view of the arrangement of the reactor and neutron generator of an embodiment of the present application;
[0043] Figure 4 A top view of the arrangement of the reactor and neutron generator of an embodiment of the present application;
[0044] Figure 5 A top view of the arrangement of the reactor and the radioactive neutron source of an embodiment of the present application;
[0045] Figure 6 This is a flow chart of installation and commissioning of the critical device and neutron generator of the embodiment of the present application;
[0046] Figure 7 A schematic diagram of the core arrangement of a critical device according to an embodiment of the present application;
[0047] Figure 8 A flowchart for realizing reactor startup for a neutron generator according to an embodiment of the present application;
[0048] Fig. 9 This is a functional block diagram of a reactor startup system according to an embodiment of the present application.
[0049] Reference numerals and corresponding component names:
[0050] 1-mobile platform, 2-control system, 3-target nuclear components, 4-acceleration unit, 5-ion source, 6-high-pressure chamber, 7-reactor body support, 8-core base, 9-neutron detector, 10-reactor core, 11-reactor barrel, 12-control rods, 13-upper grid, 14-control rod drive mechanism, 15-steel platform, 16-neutron generator, 17-radioactive neutron source. DETAILED DESCRIPTION
[0051] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with examples and drawings. The illustrative implementation scheme of the present application and its description are only used to explain the present application and are not intended to limit the present application.
[0052] Example:
[0053] During the reactor startup process, it is usually necessary to add a start-up neutron source before lifting the control rod, and collect the change trend of the neutron signal emitted by the neutron source after passing through the reactor through the neutron detector, and then use the rear-end neutron counting measurement device to analyze and process the change trend of the above neutron signal to obtain the current state of the reactor. However, the configuration of the traditional radioactive nuclide neutron source in or around the reactor core has safety hazards, uncontrollable and limited scope of application. In view of this, this embodiment proposes a reactor startup method based on a neutron generator. The method proposed in this embodiment uses a neutron generator to start the reactor, so that it is not necessary to configure a traditional radioactive nuclide neutron source in or near the reactor core, optimize the configuration of the research reactor, and eliminate the inherent risks of the radioactive neutron source. At the same time, since the neutrons generated by the neutron generator are controllable to start and stop and the intensity is adjustable, it is more conducive to optimizing the physical startup process of the reactor, and thus can improve the core safety performance while optimizing the layout of the reactor core. In addition, the neutron generator has many advantages such as producing monoenergetic neutrons, controllable yield, mobility and reusability, which can greatly reduce equipment costs, have huge economic benefits, and provide safer, more effective and economical technical support for reactor startup.
[0054] The neutron generator used in this embodiment refers to a device that can generate a neutron beam by bombarding a target nucleus with particles, and mainly includes an ion source 5, a high-pressure chamber 6, an acceleration unit 4, a control system 2, a mobile platform 1, and a target nucleus component 3. Figure 1 As shown. The function of the neutron generator is to produce a high-current neutron beam with controllable intensity and single energy. The neutron generator can be used to carry out nuclear technology applications such as neutron cross-section measurement, neutron irradiation breeding, neutron detector calibration, neutron photography, and neutron activation analysis. For example, the neutron beam produced by the neutron generator is nearly monoenergetic, which is suitable for measuring the neutron cross-section data of different materials. The high-current neutron beam can also be used to calibrate the neutron detectors used in the nuclear measurement systems, control and protection systems, and test measurement systems of the reactor to measure the sensitivity of each neutron detector and confirm that the neutron detector is in a fully functional state.
[0055] like Figure 2 As shown, the reactor startup method proposed in this embodiment specifically includes the following steps:
[0056] Step 100, using a reactor physics calculation program to establish a reactor theoretical model and perform model verification.
[0057] This step 100 uses a reactor physics calculation program based on Monte Carlo to establish a reactor theoretical model. When modeling, the reactor physics calculation program is used to follow the principle of gradual refinement from the inside out, and the reactor core (including nuclear fuel, control rods, poison rods, moderators), neutron detectors, neutron generators and other components are modeled in detail. During the modeling process, in order to find the critical rod positions of different control rods, all control rods are set to be able to move freely up and down. After the above reactor theoretical model is established, it is necessary to use multiple critical rod position measured values to perform model calibration and verification on the reactor theoretical model. The calibration and verification conditions meet the deviation between the measured value and the calculated value does not exceed the preset value.
[0058] Specifically, in step 100, a general critical device is taken as an example, and a reactor physics calculation program is used to perform detailed modeling of the core 10, core base 8, reactor body support 7, steel platform 15, neutron generator 16, neutron detector 9, reactor barrel 11, control rod 12, upper grid plate 13 and control rod drive mechanism 14 of the critical device. The schematic diagram of the combination of the above components is shown in FIG. Figure 3 and Figure 4 shown.
[0059] After the above reactor theoretical model was established, the model was calibrated using the measured values of 7 critical rod positions. Table 1 shows the K values of the 7 critical rod positions. eff The comparison results between the measured values and the calculated values of the reactor theoretical model show that from Table 1, the maximum deviation between the measured values and the calculated values is 3.53‰, indicating that the established reactor theoretical model is correct.
[0060] Table 1K eff Comparison between measured and calculated values
[0061] Critical rod position number Measured value Calculated Value deviation(‰) 1 1.0 1.00083 0.83 2 1.0 1.00164 1.64 3 1.0 0.99921 -0.79 4 1.0 1.00374 3.74 5 1.0 0.99873 -1.27 6 1.0 0.99906 -0.94 7 1.0 1.00257 2.57
[0062] Step 200, using the verified reactor theoretical model, counts the counting rate of neutrons generated by the neutron generator after passing through the core at the neutron detector to determine the neutron yield of the neutron generator that meets the reactor startup requirements.
[0063] After the reactor theoretical model has been checked and verified, the neutron yield of the neutron generator is adjusted, and the counting rate of the neutrons generated by the neutron generator after passing through the core at the neutron detector is obtained, so that the counting rate of the neutrons generated by the neutron generator after passing through the core at the neutron detector is not less than 0.5cps, thereby determining the minimum requirement for the neutron yield of the neutron generator, that is, determining the neutron yield that the neutron generator can achieve the reactor startup requirement.
[0064] Specifically, the step 200 is Figure 3 and Figure 4Taking the reactor theoretical model shown in the figure as an example, the yield of the neutron generator can be 5×10 8 n / s. Compare it with the calculated results of the americium beryllium neutron source that has been tested in the actual reactor to evaluate whether the neutron yield of the above neutron generator meets the startup requirements. The americium beryllium neutron source is used in the startup process of the above universal critical device. The americium beryllium neutron source is located in the reactor barrel about 30 cm away from the edge of the core, and the neutron detector is located on the other side of the core. Figure 5 As shown in the figure, the centers of the neutron detector, the core and the neutron source are arranged almost in the same line. When the neutron source is replaced by a neutron generator, the neutron source is taken out and the neutron generator is arranged outside the reactor barrel, with the target nuclear component of the neutron generator facing the core, as shown in the figure. Figure 4 As shown, the centers of the neutron detectors, the core and the neutron generator are arranged almost collinearly.
[0065] The neutron detector count rate on the other side when the neutron generator and neutron source exist alone is calculated separately. When modeling and calculating, all control rods are inserted to the bottom, and the intensity of the americium beryllium neutron source is about 1.1×10 7 n / s, the neutron yield of the neutron generator is 5×10 8 n / s, the neutron detector sensitivity is selected as 80n / cm -2 ·s -1 , the calculation results are shown in Table 2.
[0066] Table 2 Count rate at neutron detector
[0067]
[0068] As can be seen from Table 2, the neutron generator output is selected as 5×10 8 When n / s, the count rate and source intensity generated at the rear neutron detector are about 1.1×10 7 The neutron yield is proportional to the count rate of the neutron detector, that is, the larger the neutron yield, the larger the corresponding count rate. Therefore, in order to meet the requirements of reactor startup of various types and sizes as much as possible, the maximum neutron yield of the neutron generator can be selected to be higher than 1×10 9 n / s, and the neutron yield of the neutron generator can be freely adjusted between 0 and the maximum neutron yield. The neutron generator can be applied to a variety of reactors, and it is only necessary to adjust the required neutron yield according to actual needs.
[0069] Step 300, using a neutron generator with sufficient neutron yield (neutron yield that meets the reactor startup requirement) to replace the reactor startup neutron source, before lifting the control rod during the reactor startup process, turn on the neutron generator and maintain it in a stable neutron yield emission state to perform the reactor startup operation.
[0070] After the neutron yield of the neutron generator is determined through numerical calculation, a neutron generator with sufficient neutron yield will replace the reactor start-up neutron source to realize the reactor startup operation. Specifically, it includes:
[0071] Step 301, complete the installation and commissioning of the neutron generator outside the core. The neutron generator and the neutron detector are located on opposite sides of the core, and the neutron generator is arranged outside the reactor barrel. The target nuclear component of the neutron generator faces the core, and the centers of the neutron detector, the core and the target nuclear component are arranged almost in the same line. Taking the above critical device as an example, its installation and commissioning process is as follows: Figure 6 As shown, first, the core is arranged and the critical device joint adjustment is completed, including the installation of the core lower grid plate, the enclosure and other in-core components, the installation of the neutron detector and measuring instruments on the pile, the installation of the fuel assembly, the control rod, the poison rod, the control rod drive mechanism, and the joint adjustment of the critical device nuclear measurement, control and protection, drive mechanism and other systems; then, the neutron generator is installed and debugged, including the fixed-point arrangement and debugging of the neutron generator outside the pile, and the joint adjustment of the neutron generator and the neutron detector on the pile. It should be noted that the installation and debugging technology belongs to the conventional technical means in this field, and the specific installation and debugging methods will not be repeated here.
[0072] Step 302, after the neutron generator is installed, the neutron yield of the neutron generator is adjusted to a numerically calculated value and maintained in a stable neutron yield emission state, ensuring that the measured count rate at the rear neutron detector is greater than 0.5 cps.
[0073] In order to be applicable to the startup requirements of reactors of various types and sizes as much as possible, the continuous stable working time of the neutron generator is generally required to be longer than 1 hour. When there is an external neutron source (i.e., neutron generator) to maintain the criticality of the reactor, the number of neutrons produced is equivalent to the number of neutrons disappeared, and the stability of the neutron beam produced by the neutron generator is required. Considering the statistical fluctuation of neutrons, the stability deviation of the neutron beam produced by the neutron generator is required to be within 1%.
[0074] The neutron beam stability requirement for the neutron generator acting as the start-up neutron source is that the continuous stable working time under the start-up neutron yield conditions is longer than 1 hour, and the neutron beam deviation is within 1% at this time.
[0075] Step 303, adding reactivity according to the 1 / 2 principle, carrying out a rod raising extrapolation experiment, so that the core reaches a critical state. The rod raising extrapolation experiment specifically includes: determining the core critical rod position according to the measured value; performing multiple repeated extrapolation operations according to the 1 / 2 principle according to the core critical rod position, so that the core k effWhen it reaches 0.996, the neutron generator is cut off; then the control rods are fine-tuned to make the core transition to supercriticality, and finally the power stabilization method is used to adjust the core to the critical state. At this time, the number of neutrons produced by the reactor is equal to the number of neutrons destroyed, and the reactor startup operation is completed.
[0076] Specifically, taking the above critical device as an example, the reactor start-up operation is performed using a neutron generator to verify whether the neutron generator can sequentially start the reactor. In the above critical device, the core includes two groups of safety rods (A1, A2) and six groups of adjustment rods (K1, K2, K3, K4, K5, K6). The core is arranged as follows: Figure 7 shown.
[0077] According to the previous measured values, the critical rod positions of the core are: A1, A2, K1, K2, K3 rods are raised to the top, K4 rod is raised to 450mm, K5, K6 are at the bottom. According to this critical rod position, after the neutron generator is installed, the neutron yield of the neutron generator is adjusted to 5×10 8 n / s, ensure that the measured count rate at the rear neutron detector is greater than 0.5cps, then add reactivity according to the "1 / 2 rule" and press Figure 8 The steps shown below are to carry out the rod lifting and extrapolation experiment:
[0078] The A1 rod is lifted to the top and the moderator is injected into the core;
[0079] Lift the A2 and K2 rods to the top;
[0080] Lift the K2 rod to the top and record the neutron counting rate;
[0081] Raise the K3 rod to half height and record the neutron count rate;
[0082] According to the extrapolation result of the previous step, the K3 rod is raised according to the 1 / 2 principle;
[0083] After the K3 rod reaches the top, continue to lift the K4 rod for extrapolation according to the 1 / 2 principle;
[0084] When the extrapolated result k eff When it reaches 0.996, the neutron generator is cut off;
[0085] Fine-tune the K4 rod to keep the core critical.
[0086] After the above steps are completed, the core is successfully brought to a critical state using a neutron generator, which means that the neutron generator can replace the traditional radioactive neutron source to start the reactor. When the neutron generator is used to start the reactor in this embodiment, it is not necessary to configure the traditional radioactive nuclide neutron source in the reactor core or near the periphery, optimize the layout of the research reactor, and eliminate the inherent risks of the radioactive neutron source. At the same time, since the neutron generator is used to generate neutrons, the start and stop can be controlled and the intensity can be adjusted, which is more conducive to optimizing the physical startup process of the reactor, and thus the core safety performance can be improved while optimizing the layout of the reactor core. In addition, the neutron generator produces monoenergetic neutrons, has controllable yield, is movable, and can be reused, etc., which provides huge economic benefits for reactor startup and is of great significance. The method proposed in this embodiment can be applied to various types of research reactors, including but not limited to various types of solid, liquid and gas research reactors, and is particularly suitable for critical devices.
[0087] Based on the same technical concept as above, this embodiment also proposes a reactor startup system based on a neutron generator, such as Fig. 9 As shown, the reactor startup system proposed in this embodiment specifically includes:
[0088] The model building module is configured to: use a reactor physics calculation program to establish a reactor theoretical model and perform model verification.
[0089] The numerical calculation module is configured to: use a verified reactor theoretical model to count the counting rate of neutrons generated by the neutron generator at the neutron detector after passing through the core, and determine the neutron yield of the neutron generator that meets the reactor startup requirements.
[0090] And, a start-up module, which is configured to: use a neutron generator with sufficient neutron yield (neutron yield that meets the reactor startup requirement) to replace the start-up neutron source, and before lifting the control rod during the reactor startup process, turn on the neutron generator and maintain it in a stable neutron yield emission state to perform the reactor startup operation.
[0091] It should be noted that the specific implementation process of each functional module in the reactor startup system proposed in this embodiment is as described in the above method, and will not be repeated here.
[0092] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.
[0093] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.
[0094] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.
[0095] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.
[0096] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only the specific implementation method of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.
Claims
1. A reactor startup method based on a neutron generator, characterized in that: The reactor startup method comprises: Use reactor physics calculation program to establish reactor theoretical model and conduct model verification; The neutron yield of the neutron generator that meets the reactor startup requirements is determined by using a verified reactor theoretical model to count the neutrons generated by the neutron generator at the neutron detector after the neutrons pass through the core; A neutron generator with a neutron yield that meets the reactor startup requirements is used to replace the reactor startup neutron source. Before the control rod is lifted during the reactor startup process, the neutron generator is turned on and maintained in a stable neutron yield emission state to perform the reactor startup operation.
2. A method for starting a reactor based on a neutron generator according to claim 1, characterized in that: The method of establishing a reactor theoretical model by using a reactor physics calculation program specifically includes: Using the Monte Carlo-based reactor physics calculation program, the reactor core, neutron detector, and neutron generator are modeled in detail from the inside out and in a step-by-step manner. During the modeling process, all control rods are set to move freely up and down.
3. A method for starting a reactor based on a neutron generator according to claim 2, characterized in that: The model verification specifically includes: The reactor theoretical model is calibrated and verified using a plurality of critical rod position measured values, and the calibration and verification conditions satisfy that the deviation between the measured value and the calculated value does not exceed a preset value.
4. A method for starting a reactor based on a neutron generator according to claim 1, characterized in that: The neutron yield of the neutron generator that meets the reactor startup requirements is specifically: The counting rate of the neutrons generated by the neutron generator passing through the core at the neutron detector is not less than 0.5 cps.
5. A method for starting a reactor based on a neutron generator according to claim 4, characterized in that: The maximum neutron yield of the neutron generator is higher than 1×10 9 n / s, and the neutron yield of the neutron generator can be freely adjusted between 0 and the maximum neutron yield.
6. A method for starting a reactor based on a neutron generator according to any one of claims 1 to 5, characterized in that: The reactor startup operation specifically includes: Completing the installation and commissioning of the neutron generator outside the core; After the neutron generator is installed, the neutron yield of the neutron generator is adjusted to a numerically calculated value and maintained in a stable neutron yield emission state, ensuring that the measured count rate of the rear neutron detector is greater than 0.5 cps; Reactivity is added according to the 1 / 2 principle, and rod lifting and extrapolation experiments are carried out to bring the core to a critical state.
7. A method for starting a reactor based on a neutron generator according to claim 6, characterized in that: The installation and commissioning of the neutron generator outside the core specifically includes: The neutron generator and the neutron detector are respectively located on two opposite sides of the core, and the neutron generator is arranged outside the reactor barrel. The target nuclear component of the neutron generator, the core and the center of the neutron detector are arranged in a collinear manner.
8. A method for starting a reactor based on a neutron generator according to claim 6, characterized in that: The rod lifting and extrapolation experiment specifically includes: Determine the core critical rod position based on the measured value; According to the core critical rod position, the extrapolation operation is repeated many times according to the 1 / 2 principle to make the core k eff It reaches 0.996, at which point the neutron generator is cut off; Fine-tune the control rods to bring the core to criticality.
9. A method for starting a reactor based on a neutron generator according to claim 1, characterized in that: The neutron generator is a device that generates neutron beams through the effect of particle bombardment of target nuclei.
10. A reactor startup system based on a neutron generator, characterized in that: The reactor startup system comprises: A model building module, wherein the model building module is configured to: establish a reactor theoretical model using a reactor physics calculation program and perform model verification; A numerical calculation module, wherein the numerical calculation module is configured to: use a verified reactor theoretical model to count the counting rate of neutrons generated by the neutron generator at the neutron detector after the neutrons pass through the core, and determine the neutron yield of the neutron generator that meets the reactor startup requirements; And, a start-up module, the start-up module is configured to: use a neutron generator with a neutron yield that meets the reactor startup requirement to replace the start-up neutron source, and before lifting the control rod during the reactor startup process, turn on the neutron generator and maintain it in a stable neutron yield emission state to perform the reactor startup operation.