Simulated guide tube rod and simulated nuclear reactor

Abstract

The invention provides a simulated guide tube rod and a simulated nuclear reactor, and the simulated guide tube rod comprises a core rod which comprises a boss, a middle rod, a connector and a core rod groove; part of the core rod is located in the outer pipe, the outer pipe comprises a pipe part and an outer pipe groove for containing the boss, and first gaps are formed between the inner wall of the pipe part of the outer pipe and the outer wall of the core rod and between the inner wall of the outer pipe groove and the outer wall of the core rod; the end plug comprises a first part and a second part, the first part is matched with the core rod groove, the second part is located below the outer pipe, and the diameter of the second part is larger than or equal to that of the outer pipe; the sealing filler, the inner wall of part of the outer pipe groove, the boss and the second part jointly form a first space, and the sealing filler is located in the first space and suitable for sealing the first space. The simulated guide tube rod and the simulated nuclear reactor provided by the invention can help to solve the problem of insulation between the guide tube rod and a peripheral electrified part, and the performance of the guide tube rod is further improved.

Description

Technical Field

[0001] The present application mainly relates to the field of nuclear power technology, and in particular to a simulated guide tube rod and a simulated nuclear reactor. Background Art

[0002] The critical heat flux test (hereinafter referred to as the CHF test) is a key comprehensive test for studying the thermal performance of fuel assemblies in pressurized water reactor nuclear power plants. It is usually carried out in a large thermal hydraulic test bench that simulates the high temperature and high pressure environment of the reactor. In order to characterize the geometric characteristics of the fuel assembly prototype, simulate the heating phenomenon of the fuel rods, and monitor the temperature rise process of the rod wall when heat transfer deterioration occurs, it is necessary to design a CHF test piece. A general prototype fuel assembly may contain multiple types of grid cells, such as typical grid cells, single cold wall grid cells, edge grid cells, corner grid cells, and double cold wall grid cells.

[0003] The CHF test piece with cold wall grid element uses simulated guide tube rods to simulate the cold wall effect of the guide tube of the prototype fuel assembly. By designing the structure and arrangement of the electric heating rod and the simulated guide tube rod, the structural characteristics of the prototype fuel assembly are simulated to support the implementation of CHF test under specific working conditions. If the guide tube rod in the critical heat flux density test piece with simulated guide tube grid element is not designed properly, it may cause discharge with the electrode or other surrounding live heating rods and grids, causing the heating rod to burn out. Summary of the invention

[0004] The technical problem to be solved by the present application is to provide a simulated guide tube rod and a simulated nuclear reactor, which can help solve the insulation problem between the guide tube rod and the surrounding live parts and further improve the performance of the guide tube rod.

[0005] In order to solve the above technical problems, the present application provides a simulated guide tube rod, which is suitable for simulating a nuclear reactor, including: a core rod, the core rod including a boss, an intermediate rod, a connecting head and a core rod groove; an outer tube, part of the core rod is located in the outer tube, the outer tube includes a tube part and an outer tube groove accommodating the boss, and a first gap is provided between the inner wall of the tube part of the outer tube and the inner wall of the outer tube groove and the outer wall of the core rod; an end plug, the end plug includes a first part and a second part, the first part cooperates with the core rod groove, the second part is located below the outer tube, and the diameter of the second part is greater than or equal to the diameter of the outer tube; a sealing filler, part of the inner wall of the outer tube groove, the boss and the second part together constitute a first space, the sealing filler is located in the first space and is suitable for sealing the first space.

[0006] Optionally, the core rod is a solid rod-shaped structure.

[0007] Optionally, the connector comprises a nickel-based alloy and / or 316 stainless steel.

[0008] Optionally, the outer tube is a ceramic tube.

[0009] Optionally, the outer tube is coaxially assembled with the core rod.

[0010] Optionally, the first portion is connected to the core rod groove by threaded fitting.

[0011] Optionally, the sealing filler includes polytetrafluoroethylene and / or ceramics.

[0012] Optionally, the width of the first gap ranges from 0.1 mm to 0.3 mm.

[0013] In order to solve the above technical problems, the present application provides a simulated nuclear reactor, including a plurality of cold rods, a plurality of hot rods and a plurality of simulated guide tube rods as described above.

[0014] Optionally, the plurality of heat rods are arranged around each of the simulated guide tube rods.

[0015] Compared with the prior art, the present application can further improve the insulation performance of the simulated guide tube rod by insulating the outer tube with materials such as ceramic tubes, further by sealing the first space formed by the inner wall of the outer tube groove, the boss and the second part of the end plug, and using polytetrafluoroethylene and / or ceramics as the material of the sealing filler. At the same time, the structure of the real guide tube rod can be better simulated by setting the core rod and the end plug structure, which is convenient for simulating and studying the cold wall grid element effect of the prototype fuel assembly guide tube, and can help solve the insulation problem of the guide tube rod and the surrounding live parts, and further improve the performance of the guide tube rod. 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 application. In the accompanying drawings:

[0017] Figure 1 It is a schematic diagram of a structural cross-section of a simulated guide tube rod in one embodiment of the present application;

[0018] Figure 2 It is a schematic diagram of a partial structure of a simulated guide tube rod in one embodiment of the present application;

[0019] Figure 3 It is a schematic diagram of a partial structure of a simulated guide tube rod in one embodiment of the present application;

[0020] Figure 4 It is a schematic diagram of the partial structure of an outer tube in a simulated guide tube rod in one embodiment of the present application;

[0021] Figure 5This is a schematic diagram of the structure of an end plug simulating a guide tube rod in one embodiment of the present application;

[0022] Figure 6 It is a structural schematic diagram of a simulated nuclear reactor in one embodiment of the present application. DETAILED DESCRIPTION

[0023] 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.

[0024] 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.

[0025] 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.

[0026] In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0027] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0028] In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning and cannot be understood as limiting the scope of protection of this application. In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.

[0029] This application refers to Figure 1 to Figure 3 A simulated guide tube rod 10 is proposed, which is suitable for Figure 4 The nuclear reactor 20. Wherein, Figure 1 The schematic diagram of the overall structure cross section of the simulated guide tube rod 10 is shown. Figure 2-Figure 3 FIG. 1 shows a schematic diagram of a local structure of a simulated guide tube rod 10. Figure 1 As shown, the simulated guide tube rod 10 includes a core rod 11, an outer tube 12, an end plug 13 and a sealing filler 14. Exemplarily, the lengths of the core rod 11 and the outer tube 12 meet the insulation requirements of a full-scale CHF test rod bundle.

[0030] Specifically, refer to Figure 1 to Figure 3The mandrel 11 may be a solid rod-shaped structure, mainly including a boss 111, an intermediate rod 112, a connector 113 and a mandrel groove 114, wherein the connector 113 includes a nickel-based alloy and / or 316 stainless steel. Through the setting of the connector 113, the simulated guide tube 10 and the CHF test body (not shown) can be sealed. In other embodiments of the present application, the mandrel 11 may also adopt different structures according to specific circumstances. At the same time, the connector 113 may also be made of other metals or metal alloys with good corrosion resistance and high temperature resistance, and the present application does not limit this.

[0031] Furthermore, the simulated guide tube 10 includes an outer tube 12, and a portion of the core rod 11 is located inside the outer tube 12. Figure 4 , Figure 4 The outer tube 12 is shown in a three-dimensional structural diagram. The outer tube 12 includes a tube portion 121 and an outer tube groove 122 for accommodating the boss 111. A first gap S0 is provided between the inner wall of the tube portion of the outer tube 12 and the inner wall of the outer tube groove and the outer wall of the core rod 11, wherein the width range w1 of the first gap S0 is 0.1 mm to 0.3 mm. By setting the first gap S0, a reserved space can be provided for thermal expansion and contraction between the outer tube 12 and the core rod 11. Exemplarily, the outer tube 12 can be a ceramic tube or other materials with good high temperature resistance, corrosion resistance and insulation performance, and the present application does not limit this.

[0032] In this embodiment, the outer tube 12 and the core rod 11 are coaxially assembled. Furthermore, the outer tube groove 122 of the outer tube 12 and the boss 111 of the core rod 11 can realize the axial positioning of the outer tube 12 and the core rod 11. The outer tube groove 122 can completely wrap the boss 11, thereby effectively avoiding the discharge phenomenon between the boss 11 and the surrounding components, and providing the insulation performance of the simulated guide tube 10. The core rod 11 and the outer tube 12 can also adopt an integral integrated structural design, thereby avoiding the insulation failure problem that is easy to occur in the segmented structural design.

[0033] On the other hand, the simulated guide tube 10 further includes an end plug 13. Figure 5 Schematic diagram of the specific structure of the end plug 13 is shown. Figure 5 The end plug 13 includes a first portion 131 and a second portion 132. The first portion 131 cooperates with the core rod groove 114. For example, the first portion 131 and the core rod groove 114 can be connected by threaded cooperation. The second portion 132 is located below the outer tube 12, and the diameter of the second portion 132 is equal to the diameter of the outer tube 12. In other embodiments of the present application, the diameter of the second portion 132 can be greater than the diameter of the outer tube 12, and the present application does not limit this.

[0034] In this embodiment, the simulated guide tube 10 further includes a sealing filler 14. Part of the inner wall S2 of the outer tube groove, the boss 111 and the second portion 132 together constitute the first space A1. The sealing filler 14 is located in the first space A1 and is suitable for sealing the first space A1. Through the design of the sealing filler 14, multiple insulating sealing boundaries are formed between the outer tube 12, the core rod 11 and the end plug 13, which can ensure that the core rod 11 always maintains an insulating state. Exemplarily, the sealing filler 14 includes polytetrafluoroethylene and / or ceramics or other high temperature resistant insulating materials.

[0035] On the other hand, the present application also refers to Figure 6 A simulated nuclear reactor 20 is shown, including the simulated guide tube rods proposed in any embodiment of the present application, such as the simulated guide tube rod 10 mentioned above. The simulated nuclear reactor 20 also includes a plurality of cold rods 21 and a plurality of hot rods 22, wherein the plurality of hot rods 22 (as shown by the grid plate shadows) are arranged around each simulated guide tube rod 10 (as shown by the oblique line shadows). Figure 6 As shown, cold wall cells 61, 62, 63 and 64 can be formed between the hot rod 22 and the simulated guide tube rod 10. By simulating the cold wall cell effect of the guide tube rod 10, the CHF of the simulated guide tube rod 10, the hot rod 22 and the cold rod 21 can be obtained, thereby realizing the simulation of the cold wall cell effect of the prototype fuel assembly guide tube.

[0036] The present application can further improve the insulation performance of the simulated guide tube rod by insulating the outer tube with materials such as ceramic tubes, and further by sealing the first space formed by the inner wall of the outer tube groove, the boss and the second part of the end plug, and using polytetrafluoroethylene and / or ceramics as the material of the sealing filler. At the same time, the structure of the real guide tube rod can be better simulated by setting the core rod and the end plug structure, which is convenient for simulating and studying the cold wall grid element effect of the prototype fuel assembly guide tube, and can help solve the insulation problem of the guide tube rod and the surrounding live parts, and further improve the performance of the guide tube rod.

[0037] The basic concepts have been described above. Obviously, for those skilled in the art, the above application disclosure is only 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.

[0038] 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.

[0039] 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 application embodiments, in the above description of the embodiments of this application, multiple features are sometimes merged 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.

[0040] 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.

[0041] 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 simulated guide tube rod, suitable for simulating a nuclear reactor, characterized in that: include: A mandrel, the mandrel comprising a boss, an intermediate rod, a connector and a mandrel groove; An outer tube, part of the core rod is located in the outer tube, the outer tube comprises a tube portion and an outer tube groove accommodating the boss, and a first gap is provided between the inner wall of the tube portion of the outer tube and the inner wall of the outer tube groove and the outer wall of the core rod; An end plug, the end plug comprising a first portion and a second portion, the first portion being matched with the core rod groove, the second portion being located below the outer tube, and the diameter of the second portion being greater than or equal to the diameter of the outer tube; A sealing filler, an inner wall of a portion of the outer tube groove, the boss and the second portion together form a first space, and the sealing filler is located in the first space and is suitable for sealing the first space.

2. The simulated guide tube rod according to claim 1, characterized in that: The core rod is a solid rod-shaped structure.

3. The simulated guide tube rod according to claim 1, characterized in that: The connector includes a nickel-based alloy and / or 316 stainless steel.

4. The simulated guide tube rod according to claim 1, characterized in that: The outer tube is a ceramic tube.

5. The simulated guide tube rod according to claim 1, characterized in that: The outer tube is coaxially assembled with the core rod.

6. The simulated guide tube rod according to claim 1, characterized in that: The first portion is connected to the core rod groove through threaded cooperation.

7. The simulated guide tube rod according to claim 1, characterized in that: The sealing filler comprises polytetrafluoroethylene and / or ceramics.

8. The simulated guide tube rod according to claim 1, characterized in that: The width of the first gap ranges from 0.1 mm to 0.3 mm.

9. A simulated nuclear reactor, characterized in that: The invention comprises a plurality of cold rods, a plurality of hot rods and a plurality of simulated guide tube rods as claimed in claims 1 to 8.

10. The simulated nuclear reactor according to claim 9, characterized in that: The plurality of heat rods are disposed around each of the simulated guide tube rods.

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