阅读说明：本技术 一种棱柱式高温气冷堆下反射层、堆芯和高温气冷堆 (Prismatic high-temperature gas-cooled reactor lower reflecting layer, reactor core and high-temperature gas-cooled reactor ) 是由 董建华 张朔婷 张成龙 朱思阳 李呼昂 姚红 贺楷 杨长江 刘国明 汪俊 于 2021-07-05 设计创作，主要内容包括：本发明涉及一种棱柱式高温气冷堆下反射层、堆芯和高温气冷堆,属于核技术领域,下反射层由多个石墨砖构成,所述石墨砖内部开有腔室和槽道,所述腔室位于所述石墨砖的中心位置,用于流通冷却剂；所述槽道位于所述石墨砖的上段,槽道入口位于所述石墨砖的上端面上,并与堆芯冷却剂出口连通,槽道出口与所述腔室连通。本发明提供的下反射层结构可用于将冷却剂汇流,提高冷却剂流出堆芯的均匀性,并通过结构布置调整冷却剂流量分配以展平堆芯温度分布。(The invention relates to a prismatic high-temperature gas-cooled reactor lower reflecting layer, a reactor core and a high-temperature gas-cooled reactor, belonging to the technical field of nuclear, wherein the lower reflecting layer is composed of a plurality of graphite bricks, a cavity and a channel are arranged in the graphite bricks, and the cavity is positioned in the center of the graphite bricks and used for circulating coolant; the channel is positioned at the upper section of the graphite brick, the inlet of the channel is positioned on the upper end surface of the graphite brick and is communicated with the coolant outlet of the reactor core, and the outlet of the channel is communicated with the chamber. The lower reflecting layer structure provided by the invention can be used for converging the coolant, improving the uniformity of the coolant flowing out of the reactor core and adjusting the coolant flow distribution through structural arrangement so as to flatten the temperature distribution of the reactor core.)

1. The lower reflecting layer of the prismatic high-temperature gas-cooled reactor comprises a plurality of graphite bricks (1), and is characterized in that each graphite brick is internally provided with a chamber (3) and a plurality of coolant channels (2), wherein the chamber (3) is positioned at the center of the graphite brick (1) and used for circulating coolant;

the coolant channel (2) is positioned at the upper section of the graphite brick (1), the inlet of the coolant channel is positioned on the upper end surface of the graphite brick (1) and is communicated with the outlet of an external core coolant channel, and the outlet of the coolant channel is communicated with the chamber (3).

2. The lower reflecting layer for a prismatic high temperature gas-cooled reactor according to claim 1, wherein the chamber (3) is cylindrical.

3. The lower reflecting layer for a prismatic high-temperature gas-cooled reactor according to claim 2, wherein the coolant channels (2) are branch-shaped structures consisting of rectangular long and narrow channels.

4. The lower reflecting layer for a prismatic high temperature gas-cooled reactor according to claim 3, wherein the depth of the coolant channel (2) is gradually increased from the periphery of the graphite brick (1) toward the center.

5. The lower reflecting layer for a prismatic high temperature gas-cooled reactor according to any one of claims 1 to 4, wherein a plurality of the graphite bricks (1) are arranged in parallel in a horizontal direction.

6. A reactor core, comprising a fuel region and a lower reflecting layer arranged at the lower part of the fuel region, wherein a plurality of coolant channels are arranged in the fuel region, and the lower reflecting layer is the prismatic high temperature gas cooled reactor lower reflecting layer according to any one of claims 1 to 4.

7. The core according to claim 6, characterized in that the diameter of the cavity (3) of each graphite brick is gradually increased or decreased in the radial direction of the fuel zone.

8. The core according to claim 7, characterized in that the coolant channels (2) of each graphite brick are interfaced with each of said coolant channels on the corresponding fuel zone.

9. The core according to claim 8, characterized in that the coolant channel (2) width of each graphite brick is equal to the coolant channel diameter of the fuel zone.

10. A high temperature gas cooled reactor comprising a core, wherein the core is as claimed in any one of claims 7 to 9.

Technical Field

The invention belongs to the technical field of nuclear, and particularly relates to a lower reflecting layer of a prismatic high-temperature gas-cooled reactor, a reactor core and a high-temperature gas-cooled reactor.

Background

In the existing prismatic high-temperature gas cooled reactor, the lower reflecting layer structure only has a basic neutron reflecting function, the function of collecting fluid in each coolant channel is not designed, the function of adjusting the flow distribution of the coolant of a reactor core is also not designed, and the lower reflecting layer graphite brick is provided with through holes which are consistent with the structure of the graphite brick in the fuel area.

However, in the conventional high temperature gas cooled reactor, there are problems that coolant flow distribution is not ideal when coolant enters a core fuel region, flow field distribution is not uniform when coolant flows out of the core, and the like, which causes an excessively high local temperature of core fuel and an excessively high pressure-bearing temperature of a core lower member, and adversely affects the safe operation of the high temperature gas cooled reactor, and therefore, it is necessary to develop a new structural form of lower reflector graphite bricks to improve the safety of the high temperature gas cooled reactor.

Disclosure of Invention

In order to solve the defects in the prior art, the invention aims to provide a lower reflecting layer of a prismatic high-temperature gas-cooled reactor, a reactor core and a high-temperature gas-cooled reactor, which can converge the coolant, improve the uniformity of the coolant flowing out of the reactor core and adjust the distribution condition of the coolant flow.

In order to achieve the above purpose, the first technical scheme adopted by the invention is as follows:

the lower reflecting layer of the prismatic high-temperature gas-cooled reactor comprises a plurality of graphite bricks, wherein a cavity and a plurality of coolant channels are formed in each graphite brick, and the cavity is positioned in the center of each graphite brick and used for circulating coolant;

the coolant channel is positioned at the upper section of the graphite brick, the inlet of the coolant channel is positioned on the upper end surface of the graphite brick and is communicated with the outlet of the external core coolant channel, and the outlet of the coolant channel is communicated with the chamber.

Further, the chamber of the prismatic high temperature gas cooled reactor lower reflection layer is cylindrical.

Further, in the lower reflecting layer of the prismatic high-temperature gas-cooled reactor, the coolant channel is a branch-shaped structure formed by rectangular long and narrow channels.

Further, the depth of the coolant channel gradually increases from the periphery of the graphite brick to the center of the lower reflecting layer of the prismatic high-temperature gas-cooled reactor.

Furthermore, in the prismatic high-temperature gas-cooled reactor lower reflecting layer, a plurality of graphite bricks are distributed in parallel along the horizontal direction.

Based on the prismatic high-temperature gas cooled reactor lower reflecting layer, the second technical scheme adopted by the invention is as follows:

a reactor core comprises a fuel area and a lower reflecting layer arranged at the lower part of the fuel area, wherein a plurality of coolant channels are arranged in the fuel area, and the lower reflecting layer is the lower reflecting layer of the prismatic high-temperature gas cooled reactor.

Further, in the core as described above, the cavity diameter of each graphite brick gradually increases or decreases in the radial direction of the fuel region.

Further, in the core as described above, the coolant channels of each graphite brick are butted against each of the coolant passages on the corresponding fuel region.

Further, in the core as described above, the coolant channel width of each graphite brick is equal to the coolant passage diameter of the fuel region.

Based on the reactor core, the third technical scheme adopted by the invention is as follows:

a high-temperature gas cooled reactor comprises a reactor core, wherein the reactor core adopts the reactor core structure.

The prismatic lower reflecting layer, the reactor core and the high-temperature gas-cooled reactor have the following remarkable technical effects:

according to the lower reflecting layer, the cavities and the channels are arranged in the graphite bricks to form a branch-shaped converging channel structure, so that the coolant in the coolant channels of the graphite bricks in the fuel area of the reactor core is guided to converge towards the center, the flow of the coolant in each channel is adjusted, and the uniformity of the coolant after flowing out of the reactor core is improved, so that the overall heat exchange performance of the reactor core is improved, the temperature distribution of the reactor core is effectively flattened, the impact of the flowing coolant on lower components of the reactor core is reduced, and the safety allowance of the reactor core is increased; and the lower reflecting layer can keep larger graphite volume, thereby reducing the neutron leakage risk of the reactor core, improving the structural strength of the lower reflecting layer, ensuring the reliability and stability of the lower reflecting layer and the reactor core, and further providing powerful guarantee for the normal operation of the high-temperature gas cooled reactor.

Drawings

Fig. 1 is a schematic structural diagram of a lower reflective layer of a prismatic high temperature gas cooled reactor according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a gas flow channel structure of a lower reflection layer of the prismatic high temperature gas cooled reactor in FIG. 1;

FIG. 3 is a longitudinal sectional view of the lower reflective layer of the prismatic high temperature gas cooled reactor of FIG. 1;

wherein, 1-graphite brick; 2-coolant channels; 3-chamber.

Detailed Description

The invention is further described with reference to specific embodiments and drawings attached to the description.

As shown in fig. 1-3, the lower reflecting layer of the prismatic high-temperature gas-cooled reactor provided by the invention is composed of a plurality of graphite bricks 1, a chamber 3 and a plurality of coolant channels 2 are arranged in each graphite brick 1, the chamber 3 is positioned at the center of the graphite brick 1, and the outlet of the chamber 3 is arranged on the lower end face of the graphite brick 1 and used for circulating coolant; the coolant channel 2 is a branch-shaped structure formed by rectangular long and narrow channels, is positioned at the upper section of the graphite brick 1, the depth of the coolant channel 2 is gradually deepened from the periphery of the graphite brick 1 to the center direction, the inlet of the coolant channel 2 is positioned on the upper end surface of the graphite brick 1 and is communicated with the outlet of the coolant channel of the reactor core, and the outlet of the coolant channel 2 is communicated with the chamber 3.

The coolant in each coolant channel of the core fuel area is guided by the coolant channels 2 to be collected towards the center, and meanwhile, the adjacent coolant channels communicated together by the coolant channels 2 are mixed in the cavity 3, so that the uniformity of the coolant after flowing out of the core is improved.

Through the diameter size of adjustment cavity 3, realize the rational distribution of coolant flow in each passageway to improve the holistic heat transfer performance of reactor core, effectively flatten the temperature distribution of reactor core. The larger the diameter of the chamber 3, the lower the flow resistance, and since the fuel assembly flow channels and the lower reflector flow channels are in communication, the more coolant enters the upper fuel assembly, thus reducing the temperature of the fuel assembly; conversely, the smaller the diameter of the chamber 3, the greater the flow resistance, so the less coolant enters the upper fuel assembly, thus raising the temperature of this row of fuel assemblies.

The plurality of graphite bricks 1 are arranged in parallel in the horizontal direction. The number, shape and size of the graphite bricks 1 are determined according to the structural design requirement of the graphite reactor internals of the reactor; the structural form of the graphite bricks is mainly determined according to the requirements of the air inflow, the size, the quantity and the structural form of the coolant channel of the reactor core fuel assembly.

Each graphite brick 1 has a plurality of coolant channel inlets at the upper portion thereof, and the depth of the coolant channel 2 is smaller than the total height of the graphite brick 1. The number, size and position of the inlets of the coolant channels 2 are determined according to the structural design requirement of the core fuel assembly connected with the upper layer, and each core fuel assembly coolant channel is ensured to have the inlet of the coolant channel 2 connected with the coolant channel, so that the core coolant can flow into the mixing chamber at the bottom of the prismatic high-temperature gas cooled reactor.

In the present embodiment, the chamber 3 is cylindrical, and may have a rectangular parallelepiped shape, a polygonal prism shape, or other shapes.

In the operation process of the reactor, coolant flows in from the reactor core through an inlet of a coolant channel 2 at the upper part of a lower reflecting layer graphite brick 1, flows along the coolant channel 2 in the graphite brick 1, is converged through a converging structure of coolant holes of the lower reflecting layer, an outlet of each channel is communicated with a cavity 3, and finally flows downwards through an outlet of the cavity 3 to enter a mixing cavity at the bottom of the prismatic high-temperature gas-cooled reactor.

Based on the lower reflecting layer of the prismatic high-temperature gas-cooled reactor, the invention also provides a reactor core, which comprises a fuel area and a lower reflecting layer arranged at the lower part of the fuel area, wherein a plurality of coolant channels are arranged in the fuel area, and the lower reflecting layer is the lower reflecting layer of the prismatic high-temperature gas-cooled reactor. The coolant channels of each graphite brick are butted against each coolant channel on its corresponding fuel zone, and the coolant channel width is equal to the coolant channel diameter of the fuel zone.

Preferably, the diameter of the chamber of each graphite brick gradually increases or decreases along the radial direction of the fuel zone.

Based on the reactor core, the invention also provides a high-temperature gas cooled reactor which comprises the reactor core, wherein the reactor core adopts the reactor core structure.

According to the lower reflecting layer of the prismatic high-temperature gas-cooled reactor, the reactor core and the high-temperature gas-cooled reactor, the chambers and the channels are arranged in the graphite bricks to form a branched collecting channel structure, so that the coolant in the coolant channel of each graphite brick in the fuel area of the reactor core is guided to collect towards the center, the flow of the coolant in each channel is adjusted, and the uniformity of the coolant after flowing out of the reactor core is improved, so that the overall heat exchange performance of the reactor core is improved, the temperature distribution of the reactor core is effectively flattened, the impact of the flowing coolant on a component at the lower part of the reactor core is reduced, and the safety allowance of the reactor core is increased; and the lower reflecting layer can keep larger graphite volume, thereby reducing the neutron leakage risk of the reactor core, improving the structural strength of the lower reflecting layer, ensuring the reliability and stability of the lower reflecting layer and the reactor core, and further providing powerful guarantee for the normal operation of the high-temperature gas cooled reactor.

The above-described embodiments are merely illustrative of the present invention, which may be embodied in other specific forms or in other specific forms without departing from the spirit or essential characteristics thereof. The described embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. The scope of the invention should be indicated by the appended claims, and any changes that are equivalent to the intent and scope of the claims should be construed to be included therein.