A low by-pass reflector module, low by-pass reflector, core structure and high temperature gas cooled reactor

Abstract

The application discloses a low-side-flow reflector module, a low-side-flow reflector, a core structure and a high-temperature gas cooled reactor. The low-side-flow reflector module comprises a module body and a flow guide block. A contact surface of the module body for contacting an adjacent low-side-flow reflector module comprises a profiled area and a planar area. When two adjacent low-side-flow reflector modules are assembled, a gap flow channel is formed, and a gap flow energy dissipation area is formed in the profiled area. The flow guide block is arranged in the gap flow energy dissipation area, and separates the gap flow channel in the gap flow energy dissipation area into a first gap flow channel and a second gap flow channel. When the gap flow enters the gap flow energy dissipation area, the flow is divided into a first gap sub-flow and a second gap sub-flow by the flow guide block. The first gap sub-flow forms a reverse flow after passing through the first gap flow channel. The direction of the reverse flow is opposite to that of the second gap sub-flow. The application can increase energy loss in flow, thereby increasing flow resistance and achieving the purpose of reducing side flow.

Description

Technical Field

[0001] This invention belongs to the field of nuclear engineering technology, specifically relating to a low-bypass reflector module, a low-bypass reflector layer, a core structure, and a high-temperature gas-cooled reactor. Background Technology

[0002] The core of a high-temperature gas-cooled reactor consists of a fuel zone, a moderator zone, and a reflector zone. Due to the high temperature, a sealed steel structure cannot be used; instead, it is constructed from blocks of ceramic materials (such as graphite). This inevitably results in a large number of gaps throughout the core, allowing some coolant to bypass the core directly through these gaps. Consequently, the coolant flow rate to cool the core is lower than expected. For example, at the Shidaowan Nuclear Power Plant, due to an underestimation of the bypass flow (exceeding 30%), the plant had to operate at reduced power to avoid fuel overheating, thus failing to achieve the desired economic benefits.

[0003] Currently, the most common way to reduce bypass flow is to rely on gap-sealing resistance components. Specifically, this often involves using elastic sealing sheets, labyrinth sealing structures, etc., to directly fill or cover the bypass gap. The resistance is increased by increasing the path resistance (increasing the number of narrow slits, increasing the number of inflection points, and increasing the path length), thereby achieving the purpose of reducing bypass flow. However, due to thermal expansion, assembly, and other reasons, the gap may become larger, leading to an increase in bypass flow. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies of the prior art by providing a low-bypass reflection layer module, a low-bypass reflection layer, a core structure, and a high-temperature gas-cooled reactor, which can increase energy loss in the flow, thereby increasing flow resistance and achieving the purpose of reducing the bypass.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is:

[0006] According to a first aspect of the present invention, a low-bypass reflection layer module is provided, comprising a module body and a flow guide block, wherein:

[0007] The contact surface on the module body for contacting adjacent low-sideflow reflection layer modules includes an irregular region and a planar region. When two adjacent low-sideflow reflection layer modules are assembled, a gap flow channel is formed, and a gap flow energy dissipation region is formed in the irregular region.

[0008] The flow guide block is disposed within the gap flow energy dissipation zone and divides the gap flow channel in the gap flow energy dissipation zone into a first gap flow channel and a second gap flow channel. When the gap flow enters the gap flow energy dissipation zone, it is divided into a first gap split and a second gap split by the flow guide block. The first gap split forms a reverse flow after passing through the first gap flow channel. The reverse flow is opposite to the direction of the second gap split.

[0009] Optionally, the irregular area on the adjacent contact surface of the module body is in the opposite position to the planar area.

[0010] Optionally, the irregular region includes several grooves arranged in sequence, which can form a series of continuous flow dissipation units when two adjacent low-sideflow reflection layer modules are assembled, and the flow guide blocks are disposed in the flow dissipation units.

[0011] Optionally, the wall of the groove is arc-shaped.

[0012] Optionally, the guide block is provided with a positioning boss.

[0013] Optionally, the module body is a prism with a polygonal cross-section.

[0014] According to a second aspect of the invention, a low-bypass reflection layer is also provided, comprising a plurality of blocks, the blocks employing the low-bypass reflection layer module described above.

[0015] Optionally, a positioning pin and a positioning groove are provided between the low-sideflow reflection layer module and the low-sideflow reflection layer module.

[0016] According to a third aspect of the present invention, a core structure is also provided, comprising a fuel layer and the aforementioned low-bypass reflection layer, wherein the low-bypass reflection layer is disposed around the fuel layer.

[0017] Optionally, the core structure further includes an inner reflector layer and / or an outer reflector layer, wherein the inner reflector layer is disposed between the fuel layer and the low-bypass reflector layer, and the outer reflector layer is disposed around the low-bypass reflector layer.

[0018] According to a fourth aspect of the present invention, a high-temperature gas-cooled reactor is also provided, comprising a core, wherein the core employs the core structure described above.

[0019] Beneficial effects:

[0020] The low-bypass reflector module, low-bypass reflector layer, core structure, and high-temperature gas-cooled reactor of this invention, through special structural design optimization of the reflector module, can increase energy loss in the flow, thereby increasing flow resistance and achieving the purpose of reducing bypass flow. Simultaneously, since the resistance is mainly caused by energy dissipation due to the collision between the first and second gap diversions, bypass flow can be reduced without decreasing the flow area. This ensures that changes in the gap area during assembly and operation after engineering construction will not cause significant changes in bypass flow rate, guaranteeing consistency between design and product, and preventing substantial economic losses due to design deviations. Attached Figure Description

[0021] Figure 1This is a schematic diagram of the low-bypass reflection layer module in Embodiment 1 of the present invention;

[0022] Figure 2 This is a schematic diagram of the flow guide block in Embodiment 1 of the present invention;

[0023] Figure 3 This is a schematic diagram of the gap flow channel between the transverse low-sideflow reflective layer modules in Embodiment 1 of the present invention;

[0024] Figure 4 This is a cross-sectional schematic diagram of the transverse gap flow channel in Embodiment 1 of the present invention;

[0025] Figure 5 This is a schematic diagram of the gap flow channel between the longitudinal low-side-flow reflective layer modules in Embodiment 1 of the present invention;

[0026] Figure 6 This is a cross-sectional schematic diagram of the longitudinal gap flow channel in Embodiment 1 of the present invention;

[0027] Figure 7 This is a schematic diagram of the longitudinal gap flow in Embodiment 1 of the present invention;

[0028] Figure 8 This is a schematic diagram of the transverse gap flow in Embodiment 1 of the present invention;

[0029] Figure 9 This is a schematic diagram of the gap flow in Embodiment 1 of the present invention;

[0030] Figure 10 This is a schematic diagram of the low-bypass reflection layer module in Embodiment 2 of the present invention;

[0031] Figure 11 This is a schematic diagram of the low-bypass reflection layer module in Embodiment 3 of the present invention;

[0032] Figure 12 This is a schematic diagram of the low-bypass reflection layer in Embodiment 4 of the present invention;

[0033] Figure 13 This is a schematic diagram of the low-bypass reflection layer in Embodiment 5 of the present invention;

[0034] Figure 14 This is a schematic diagram of the first core structure in Embodiment 7 of the present invention;

[0035] Figure 15 This is a schematic diagram of the second core structure in Embodiment 7 of the present invention;

[0036] Figure 16 This is a schematic diagram of the third core structure in Embodiment 7 of the present invention;

[0037] Figure 17This is a schematic diagram of the fourth core structure in Embodiment 7 of the present invention.

[0038] In the diagram: 1-Low bypass reflector layer module; 2-Gap flow channel; 3-Guide block; 4-Fuel layer; 5-Inner reflector layer; 6-Outer reflector layer; 10-Low bypass reflector layer; 7-Gap flow; 8-First gap split; 9-Second gap split; 15-Flow dissipation unit; 16-Irregular region; 17-Planar region; 11, 14, 22, 23-Gap flow energy dissipation region; 12, 13, 21, 24-Gap flow normal region; 25-Intersection point; 26-Irregular quadrilateral prism; 27-Rectangular prism; 28-First irregular pentagonal prism; 29-Second irregular pentagonal prism. Detailed Implementation

[0039] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0040] In the description of this invention, it should be noted that the terms "above" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience and simplification of the description and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0041] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connection," "setting," "installation," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] It is understood that, without conflict, the various embodiments and features in the embodiments of the present invention can be combined with each other.

[0044] It is understood that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, while the parts unrelated to the present invention are not shown in the drawings.

[0045] Currently, high-temperature gas-cooled reactors use sealed resistance components to control bypass flow, but this cannot avoid problems such as increased gaps due to thermal expansion and assembly, leading to increased bypass flow. This invention provides a low-bypass-flow reflector module, including a module body and a flow guide block. The contact surface on the module body for contact with adjacent low-bypass-flow reflector modules includes a shaped region and a planar region. When two adjacent low-bypass-flow reflector modules are assembled, a gap flow channel is formed. A gap flow energy dissipation region is formed in the shaped region of the two adjacent contact surfaces, and a gap flow normal region is formed in the planar region of the two adjacent contact surfaces. In other words, the gap flow channel includes a gap flow energy dissipation region and a gap flow normal region. The flow guide block is located within the gap flow energy dissipation region (i.e., the shaped region) and separates the gap flow channel within the gap flow energy dissipation region. The first gap flow channel and the second gap flow channel are used. When the gap flow enters the gap flow energy dissipation zone, it is divided into the first gap flow and the second gap flow by the guide block. The first gap flow forms a reverse flow after passing through the special flow channel (i.e. the first gap flow channel) formed by the irregular area and the guide block. The reverse flow is opposite to the direction of the second gap flow in the second gap flow channel. When the first gap flow and the second gap flow intersect (i.e. merge), they collide due to the different flow directions of the two gap flows, resulting in energy loss. This is manifested as a large resistance when passing through the gap flow energy dissipation zone, which increases the flow resistance and thus reduces the side flow.

[0046] Furthermore, the present invention also provides a low sideflow reflection layer comprising a plurality of blocks, which are stacked together, and the blocks employ the low sideflow reflection layer module described above.

[0047] Furthermore, the present invention also provides a core structure, including a fuel layer and the aforementioned low-bypass reflection layer, wherein the low-bypass reflection layer is disposed on the periphery of the fuel layer.

[0048] Furthermore, the present invention also provides a high-temperature gas-cooled reactor, including a reactor core, and the reactor core adopts the reactor core structure described above.

[0049] The low-bypass reflector module, low-bypass reflector layer, core structure, and high-temperature gas-cooled reactor of the present invention, through special structural design optimization of the reflector module, can increase energy loss in the flow, thereby increasing flow resistance and achieving the purpose of reducing bypass.

[0050] Example 1

[0051] like Figures 1-13 As shown, this embodiment discloses a low-bypass reflection layer module, including a module body and a flow guide block, wherein:

[0052] The module body is a prism with a polygonal cross-section. The contact surfaces on the module body for contacting the adjacent low-sideflow reflection layer module 1 include an irregular region 16 and a planar region 17. When two adjacent low-sideflow reflection layer modules 1 are assembled, they form a gap flow channel 2, and a gap flow energy dissipation region is formed in the irregular region 16 and a gap flow normal region is formed in the planar region 17.

[0053] The guide block 3 is located in the gap flow energy dissipation zone and divides the gap flow channel 2 in the gap flow energy dissipation zone into a first gap flow channel and a second gap flow channel. When the gap flow 7 enters the gap flow energy dissipation zone, it is divided into a first gap flow 8 and a second gap flow 9 by the guide block. The first gap flow 8 forms a reverse flow after passing through the first gap flow channel. The reverse flow is opposite to the direction of the second gap flow 9.

[0054] Specifically, such as Figure 1 As shown, the module body can be a trapezoidal prism, with its contact surfaces labeled A, B, C, and D. Each of these surfaces is divided into a shaped area 16 and a planar area 17, but the positions of the shaped and planar areas on surfaces A and C are opposite to those on surfaces B and D. During assembly, as... Figure 3 , Figure 5 As shown, a transverse low-sideflow gap channel 2 can be formed between surface B and surface D, and a longitudinal low-sideflow gap channel 2 can be formed between surface A and surface C.

[0055] In this embodiment, the low-side-flow reflection layer module 1 generates two types of gap flows 7 after assembly: longitudinal gap flows 7 (such as...). Figure 7 (as shown) and transverse gap flow 7 (as shown) Figure 8 (As shown). Due to the presence of irregular region 16 and planar region 17 on the contact surface of the module, both types of gap flows 7 have gap flow energy dissipation region and gap flow normal region. Among them, the resistance of the gap flow energy dissipation region is large, while the resistance of the gap flow normal region is normal.

[0056] like Figure 7 , Figure 8 As shown, it is assembled from four adjacent low-sideflow reflection layer modules 1, forming two interstitial flows 7, one longitudinal and one transverse. Among them, 11, 14, 22, and 23 are interstitial flow energy dissipation regions, and 12, 13, 21, and 24 are interstitial flow ordinary regions. The fluid corresponding to each region is denoted as f. 11 f 14 f 22 f 23 f 12 f13 f 21 f 24 Each gap flow , , , Both flows pass through a gap flow energy dissipation region and a gap flow normal region. The high resistance in the gap flow energy dissipation region significantly reduces the bypass flow rate. Although the fluid will flow towards the low-resistance region, if it wants to flow from f... 12 and f 13 Flow to f 21 or f 24 It must pass through intersection 25 (e.g. Figure 9 As shown in the diagram, the flow area at intersection 25 is much smaller than the flow area of ​​the ordinary flow zone in the gap, resulting in a much higher flow velocity through intersection 25 and a significantly increased resistance. Assuming the flow area at intersection 25 is 1mm × 1mm and the flow area of ​​the ordinary flow zone in the gap is 200mm × 1mm, then the resistance through intersection 25 is (200) times that of the ordinary flow zone in the gap. 2 =40,000 times, which will greatly inhibit gap flow f 12 and f 13 To f 21 or f 24 Flow. As can be seen from the above structure, the sideflow in the two gaps generated by the assembly of the low sideflow reflective layer module will be greatly reduced.

[0057] In some embodiments, the irregular region 16 includes a plurality of grooves arranged in sequence. When two adjacent low-sideflow reflection layer modules 1 are assembled, the grooves on the contact surfaces of the two modules can be joined together to form a series of continuous flow dissipation units 15. That is, the gap flow energy dissipation region includes a series of flow dissipation units 15 connected in series. The guide block 3 is disposed in the upper flow dissipation unit 15. After the gap flow 7 enters the flow dissipation unit 15, it will be divided into a first gap split flow 8 and a second gap split flow 9. By connecting multiple flow dissipation units 15 in series, the energy loss can be increased and the resistance can be increased.

[0058] In some implementations, the walls of the grooves are arc-shaped, meaning that the walls of the forward and reverse flow second gap channels in each flow dissipation unit do not cause abrupt changes in the flow direction of the gap flow, thus minimizing the impact of structural resistance on the flow and relying mainly on energy loss from collisions to reduce the sideflow.

[0059] Compared to traditional methods that typically increase resistance in the flow path (e.g., by setting up square flow deflectors to create right-angle bends in the flow path), the flow guide block 3 in this embodiment does not act as a blockage, but rather guides the flow without generating significant resistance while changing the flow direction. The lower the resistance, the better, and the bypass flow is mainly reduced by relying on the energy loss from the collision of the two gaps.

[0060] In some embodiments, the guide block 3 is provided with a positioning boss 30 to ensure the minimum width of the first gap flow channel and the second gap flow channel. On the one hand, this can reduce the impact of assembly error and expansion deformation (which is very small and can even be ignored). On the other hand, it can ensure that the first gap split 8 and the second gap split 9 have similar flow distribution. However, even if there is a difference, a large amount of such small flow channels can still generate huge energy loss and increase flow resistance.

[0061] Specifically, the positioning boss 30 can be a protrusion or a protrusion line, but is not limited to these.

[0062] Example 2

[0063] This embodiment discloses a low-bypass reflection layer module, which differs from Embodiment 1 in that:

[0064] like Figure 10 As shown, the order of the irregular area 16 and the ordinary area 17 on the contact surface is the opposite of that in Example 1.

[0065] Example 3

[0066] This embodiment discloses a low-bypass reflection layer module, which differs from Embodiment 1 in that:

[0067] like Figure 11 As shown, the longitudinal contact surfaces of the module body (e.g., surfaces B and D) are oblique and not perpendicular to the longitudinal gap flow channel 2.

[0068] Example 4

[0069] This embodiment discloses a low-bypass reflection layer module, which differs from Embodiment 1 in that:

[0070] like Figure 12 As shown, the module body is not a trapezoidal prism, but an irregular quadrilateral prism 26 and a rectangular prism 27.

[0071] Example 5

[0072] This embodiment discloses a low-bypass reflection layer module, which differs from Embodiment 1 in that:

[0073] like Figure 13As shown, the module body is a first irregular pentagonal prism 28 and a second irregular pentagonal prism 29, and the gap flow channel is non-linear.

[0074] The low-bypass reflective layer modules in Examples 1-5 can increase energy loss in the flow, thereby increasing flow resistance and achieving the goal of reducing bypass flow. Simultaneously, since the resistance is mainly caused by energy dissipation resulting from the collision between the first and second gaps, bypass flow can be reduced without decreasing the flow area. This ensures that changes in the gap area during assembly and operation after project construction will not cause significant changes in bypass flow rate, guaranteeing consistency between design and product, and preventing substantial economic losses due to design deviations.

[0075] Example 6

[0076] This embodiment discloses a low sideflow reflection layer, which includes multiple blocks, and the blocks adopt the low sideflow reflection layer module 1 described in any one of embodiments 1 to 5 above.

[0077] In some embodiments, positioning pins and positioning grooves may be provided between the low-sideflow reflection layer module 1 and the low-sideflow reflection layer module 2 to ensure accurate positioning and prevent misalignment of the contact surfaces of adjacent modules, which would prevent the formation of such a layer. Figure 4 , 6 The effective clearance flow channel shape is shown.

[0078] The low bypass reflection layer of this embodiment, since it includes the low bypass reflection module described in any one of embodiments 1 to 5, can also increase energy loss in the flow, thereby increasing flow resistance, achieving the purpose of reducing bypass flow and other effects, which will not be elaborated here.

[0079] Example 7

[0080] This embodiment discloses a reactor core structure, including a fuel layer and a low-bypass reflection layer as described in Embodiment 6, wherein the low-bypass reflection layer is disposed on the periphery of the fuel layer.

[0081] In some implementations, such as Figure 14 , Figure 15 As shown, the cross-section of this core structure can be hexagonal or octagonal, but is not limited to these, and will not be elaborated here.

[0082] In some implementations, such as Figure 16 , Figure 17 As shown, the core structure also includes an inner reflector layer 5 and / or an outer reflector layer 6. The inner reflector layer 5 is located inside the low bypass reflector layer 10, that is, between the fuel layer 4 and the low bypass reflector layer 10. The outer reflector layer 6 is located outside the low bypass reflector layer 10 to fill the irregular area between the low bypass reflector layer 10 and the fuel layer 4, and to further increase the bypass resistance through a labyrinth seal.

[0083] The core structure of this embodiment, since it includes the low bypass reflection layer described in Embodiment 6, can also increase energy loss in the flow, thereby increasing flow resistance, achieving the purpose of reducing bypass and other effects, which will not be elaborated here.

[0084] Example 8

[0085] This embodiment discloses a high-temperature gas-cooled reactor, including a reactor core, and the reactor core adopts the reactor core structure described in Embodiment 7.

[0086] The high-temperature gas-cooled reactor in this embodiment adopts the core structure described in Embodiment 7, which can also increase energy loss in the flow, thereby increasing flow resistance, achieving the purpose of reducing bypass flow and other effects, which will not be elaborated here.

[0087] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A low-bypass reflection layer module, characterized in that, Includes the module body and the flow guide block. The contact surface on the module body for contacting adjacent low-sideflow reflection layer modules includes an irregular region and a planar region. When two adjacent low-sideflow reflection layer modules are assembled, a gap flow channel is formed, and a gap flow energy dissipation region is formed in the irregular region. The flow guide block is disposed within the gap flow energy dissipation zone and divides the gap flow channel in the gap flow energy dissipation zone into a first gap flow channel and a second gap flow channel. When the gap flow enters the gap flow energy dissipation zone, it is divided into a first gap split and a second gap split by the flow guide block. The first gap split forms a reverse flow after passing through the first gap flow channel. The reverse flow is opposite to the direction of the second gap split.

2. The low-bypass reflection layer module according to claim 1, characterized in that, The irregularly shaped area on the adjacent contact surface of the module body is in the opposite position to the planar area.

3. The low-bypass reflection layer module according to claim 1 or 2, characterized in that, The irregular region includes several grooves arranged in sequence. When two adjacent low-side-flow reflection layer modules are assembled, they can form a series of continuous flow dissipation units. The flow guide blocks are disposed in the flow dissipation units.

4. The low-bypass reflection layer module according to claim 3, characterized in that, The wall of the groove is arc-shaped.

5. The low-bypass reflection layer module according to claim 3, characterized in that, The guide block is provided with a positioning boss.

6. The low-bypass reflection layer module according to claim 5, characterized in that, The module body is a prism with a polygonal cross-section.

7. A low-bypass reflection layer, comprising a plurality of blocks, characterized in that, The block adopts the low-side-flow reflection layer module as described in any one of claims 1 to 6.

8. The low-bypass reflection layer according to claim 7, characterized in that, A positioning pin and a positioning groove are provided between the low-sideflow reflection layer module and the low-sideflow reflection layer module.

9. A core structure, characterized in that, It includes a fuel layer and a low-bypass reflection layer as described in claim 7 or 8, wherein the low-bypass reflection layer is disposed on the periphery of the fuel layer.

10. The core structure according to claim 9, characterized in that, It also includes an inner reflective layer and / or an outer reflective layer. The inner reflective layer is disposed between the fuel layer and the low bypass reflective layer, and the outer reflective layer is disposed around the low bypass reflective layer.

11. A high-temperature gas-cooled reactor, comprising a core, characterized in that, The reactor core adopts the reactor core structure described in any one of claims 9 to 10.

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