A fuel assembly cooling system in a lead-based nuclear reactor experimental device

Abstract

The application discloses a kind of fuel assembly cooling systems in lead-based nuclear reactor experimental device, including fuel assembly and cooling component, the fuel assembly includes sleeve and heating rod fixed in sleeve, installation flange is provided on the sleeve, the sleeve is installed on reaction tank by installation flange, first air hole and second air hole are opened on the lateral wall of the sleeve;The upper end of the reaction tank is provided with through hole, the outside of the sleeve is provided with gas cooler, the air outlet end of the air cooler is connected with gas pump and is connected with gas pump by air pipe, the air outlet end of the gas pump is connected with air inlet pipe, the air inlet pipe is connected with the through hole on the reaction tank to deliver cooling gas into reaction tank.The cooling gas is circulated into the sleeve, and the heating rod in the sleeve is cooled cyclically, to avoid high temperature damage of the heating rod in the lead-based nuclear reactor, thereby improving the service life of the heating rod, and avoiding frequent replacement of the heating rod.

Description

Technical Field

[0001] This invention relates to the field of nuclear reactor technology, and more specifically to a fuel assembly cooling system in a lead-based nuclear reactor experimental apparatus. Background Technology

[0002] Lead-based reactors are one of the reference reactor types for fourth-generation nuclear energy systems. They use lead as the coolant medium and are expected to be among the first fourth-generation nuclear energy systems to achieve industrial demonstration and commercial application. Due to the excellent thermal conductivity, sufficient tritium breeding ratio, relatively simple design, and attractiveness in terms of economy and safety of lead-based materials (such as lead-lithium alloys) cladding, they have attracted considerable attention in the international field of nuclear fusion reactor research.

[0003] CLEAR-S is an integrated test facility for lead-based reactors using a liquid heavy metal pool. The core of a lead-based nuclear reactor is located at the center of a pressure vessel and consists of multiple fuel assemblies with identical geometry and mechanical structure. Heated fuel rods are installed in the fuel assemblies, and the nuclear energy released from nuclear fission in the fuel rods is immediately converted into heat energy and removed by a coolant made of lead-based material.

[0004] The fuel assembly contains multiple heating rods inserted into a sleeve. The fuel assembly extends into the reaction vessel, which is filled with an aluminum-based cooling medium. However, at the connection outlet between the fuel assembly and the reaction vessel, there is no aluminum-based cooling medium. Overheating of the heating rods in this area can easily burn them out. Figure 3 Region A is shown. Therefore, improvements to the fuel assemblies of existing lead-based nuclear reactors are required. Summary of the Invention

[0005] The purpose of this invention is to solve the above-mentioned technical problems and provide a fuel assembly cooling system for a lead-based nuclear reactor experimental device.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A fuel assembly cooling system for a lead-based nuclear reactor experimental device includes a fuel assembly and a cooling assembly. The fuel assembly includes a sleeve and a heating rod fixed inside the sleeve. The sleeve is provided with a mounting flange and is mounted on a reactor vessel via the mounting flange. The lower end of the sleeve extends into the reactor vessel, which is filled with an aluminum-based cooling medium. A first vent hole and a second vent hole are provided on the side wall of the sleeve. The first vent hole is located on the inner wall of the reactor vessel where the sleeve is located and is above the liquid level of the aluminum-based cooling medium in the reactor vessel. The second vent hole is located on the side above the mounting flange.

[0008] The upper end of the reaction vessel has a through hole, and a gas cooler is provided on the outside of the sleeve. The outlet end of the air cooler is connected to an air pump and is connected to the air pump through an air pipe. The outlet end of the air pump is connected to an air inlet pipe. The air inlet pipe is connected to the through hole on the reaction vessel to deliver cooling gas to the reaction vessel. The second vent hole is connected to an outlet pipe. The outlet pipe is connected to the air inlet end of the gas cooler to guide the hot gas discharged from the sleeve into the gas cooler for cooling.

[0009] By delivering cooling gas into the reaction vessel and then into the sleeve through the first vent, the heating rod is cooled. The discharged gas is then delivered to the gas cooler through the outlet pipe for further cooling. This process is repeated to cool the heating rod, thereby preventing it from burning out due to excessive heat and extending its service life.

[0010] Furthermore, the cooling gas is Ar gas.

[0011] Furthermore, a first control valve is connected in series on the intake pipe, which is used to control the flow of the medium inside the intake pipe.

[0012] Furthermore, a second control valve is connected in series with the vent pipe, which is used to control the flow of the medium inside the vent pipe.

[0013] The present invention provides a fuel assembly cooling system for a lead-based nuclear reactor experimental apparatus, which has the following beneficial effects: it effectively solves the problem of overheating of the central conductor of the heating rod within the fuel assembly by using Ar gas to cool the central region of the fuel assembly. Ar gas enters the gas phase space at the top of the main container reactor through a through-hole in the top cover, then enters the heating zone of the central conductor of the sleeve through a first vent hole on the sleeve wall of the heating assembly. The Ar gas is then led out of the container through a second vent hole at the top of the sleeve and transported to a gas cooler for cooling. The cooling gas circulates back into the sleeve to circulate and cool the heating rods inside, preventing high-temperature damage to the heating rods in the lead-based nuclear reactor, thereby increasing the service life of the heating rods and avoiding frequent replacements. Attached Figure Description

[0014] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings:

[0015] Figure 1 This invention provides a schematic diagram of the structure of a fuel assembly cooling system in a lead-based nuclear reactor experimental apparatus.

[0016] Figure 2 This invention provides a schematic diagram of the cooling gas flow direction in the fuel assembly cooling system of a lead-based nuclear reactor experimental device.

[0017] Figure 3 This is a schematic diagram of the background technology.

[0018] The following are the labels in the diagram: 1. Fuel assembly; 11. Sleeve; 111. First vent; 112. Second vent; 12. Heating rod; 13. Mounting flange; 2. Cooling assembly; 21. Gas cooler; 22. Gas pump; 23. Inlet pipe; 24. First control valve; 25. Outlet pipe; 26. Second control valve; 3. Reactor; 31. Through hole; 4. Aluminum-based cooling medium. Detailed Implementation

[0019] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that in the embodiments of the present invention, all directional indications (such as up-down-left-right-forward-backward...) are only used to explain the relative positional relationship and movement between the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly. The connection can be a direct connection or an indirect connection.

[0022] like Figures 1-2 As shown, a fuel assembly cooling system in a lead-based nuclear reactor experimental device includes a fuel assembly 1 and a cooling assembly 2. The fuel assembly 1 includes a sleeve 11 and a heating rod 12 fixed inside the sleeve 11. The sleeve 11 is provided with a mounting flange 13. The sleeve 11 is mounted on a reactor vessel 3 through the mounting flange 13. The lower end of the sleeve extends into the reactor vessel 3. The reactor vessel 3 is filled with an aluminum-based cooling medium 4. A first vent hole 111 and a second vent hole 112 are provided on the side wall of the sleeve 11. The first vent hole 111 is located on the pipe wall inside the reactor vessel 3 where the sleeve is located, and the first vent hole 111 is located above the liquid surface of the aluminum-based cooling medium 4 in the reactor vessel 3. The second vent hole 112 is located on the side above the mounting flange 13.

[0023] The upper end of the reaction vessel 3 is provided with a through hole 31. A gas cooler 21 is provided on the outside of the sleeve 11. The outlet end of the air cooler is connected to an air pump 22 and is connected to the air pump 22 through an air pipe. The outlet end of the air pump 22 is connected to an air inlet pipe 23. The air inlet pipe 23 is connected to the through hole 31 on the reaction vessel 3 to deliver cooling gas to the reaction vessel 3. An outlet pipe 25 is connected to the second vent 112. The outlet pipe 25 is connected to the air inlet end of the gas cooler 21 to guide the hot gas discharged from the sleeve 11 into the gas cooler 21 for cooling.

[0024] Cooling gas is supplied to the reaction vessel 3 and enters the sleeve 11 through the first vent 111 to cool the heating rod 12. The discharged gas is then supplied to the gas cooler 21 through the outlet pipe 25 for further cooling. This process is repeated to cool the heating rod 12, thus preventing it from overheating and burning out, and extending its service life. Specifically, Ar gas is used as the cooling gas.

[0025] Specifically, a first control valve 24 is connected in series on the intake pipe 23, and the first control valve 24 is used to control the flow of the medium inside the intake pipe 23. A second control valve 26 is connected in series on the outlet pipe 25, and the second control valve 26 is used to control the flow of the medium inside the outlet pipe 25. By setting the first control valve 24 and the second control valve 26, it is convenient to control the on / off state of the pipeline.

[0026] Working principle: To solve the overheating problem in the middle of the heating rod 12 in the CLEAR-S heating assembly, Ar gas is used to cool the middle area of ​​the fuel assembly 1. The cooling assembly 2 mainly includes a gas pump 22, a gas cooler 21, and related pipelines and valves; Ar gas enters the gas phase space above the main container reaction tank 3 through a through hole 31 on the top cover of the main container reaction tank 3, and then enters the middle conductor heating area of ​​the sleeve 11 through the first vent hole 111 on the wall of the sleeve 11 in the heating assembly. The Ar gas is led out of the container through the second vent hole 112 above the sleeve 11 and delivered to the gas cooler 21 for cooling. The cooling gas circulates back into the sleeve 11 to circulate and cool the heating rod 12 inside the sleeve 11. Due to the different structure of CLEAR-S, there is a partition inside the flange connection to block the pipe from going in, making it inconvenient to arrange the conveying pipe inside, and it is inconvenient for the cooling gas to enter the interior from the upper end of the sleeve 11 to cool the heating rod in the middle; In this application, the cooling gas enters the container from the upper end of the reaction tank 3 and then enters the sleeve 11 through the first vent hole 111, which facilitates the cooling gas to cool the heating rod in the sleeve 11.

[0027] The parts not covered in this technical solution can be implemented using existing technologies.

[0028] The foregoing has shown and described the basic principles, main features, and characteristics of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection of this invention includes the appended claims and their equivalents.

Claims

1. A fuel assembly cooling system in a lead-based nuclear reactor experimental apparatus, characterized in that: The device includes a fuel assembly (1) and a cooling assembly (2). The fuel assembly (1) includes a sleeve (11) and a heating rod (12) fixed inside the sleeve (11). The sleeve (11) is provided with a mounting flange (13). The sleeve (11) is mounted on a reaction vessel (3) through the mounting flange (13). The lower end of the sleeve extends into the reaction vessel (3). The reaction vessel (3) is filled with an aluminum-based cooling medium (4). A first vent hole (111) and a second vent hole (112) are provided on the side wall of the sleeve (11). The first vent hole (111) is located on the pipe wall inside the reaction vessel (3) where the sleeve is located, and the first vent hole (111) is located above the liquid surface of the aluminum-based cooling medium (4) in the reaction vessel (3). The second vent hole (112) is located on the side above the mounting flange (13). The upper end of the reaction vessel (3) is provided with a through hole (31). A gas cooler (21) is provided on the outside of the sleeve (11). The outlet end of the gas cooler (21) is connected to a gas pump (22) and is connected to the gas pump (22) through a gas pipe. The outlet end of the gas pump (22) is connected to an inlet pipe (23). The inlet pipe (23) is connected to the through hole (31) on the reaction vessel (3) to deliver cooling gas to the reaction vessel (3). The second vent hole (112) is connected to an outlet pipe (25). The outlet pipe (25) is connected to the inlet end of the gas cooler (21) to guide the hot gas discharged from the sleeve (11) into the gas cooler (21) for cooling.

2. The fuel assembly cooling system in a lead-based nuclear reactor experimental apparatus according to claim 1, characterized in that: The cooling gas used is Ar gas.

3. The fuel assembly cooling system in a lead-based nuclear reactor experimental apparatus according to claim 2, characterized in that: A first control valve (24) is connected in series on the air intake pipe (23). The first control valve (24) is used to control the flow of medium inside the air intake pipe (23).

4. The fuel assembly cooling system in a lead-based nuclear reactor experimental apparatus according to claim 2, characterized in that: The vent pipe (25) is connected in series with a second control valve (26), which is used to control the flow of the medium inside the vent pipe (25).

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