CN112133455B - A dual-mode reactor core - Google Patents

Abstract

The invention belongs to the technical field of dual-mode reactors, and particularly relates to a core of a dual-mode reactor. The fuel (1) is stacked to form a cylindrical reactor core active area with an axis position as a through hole, a plurality of hydrogen flow channels (3) are arranged on the fuel (1), a single-layer container (4) is arranged on the outer side of the reactor core active area and the inner side of the through hole, and a heat pipe (2) is arranged on one side, not close to the fuel (1), of the single-layer container (4). According to the invention, the heat pipe (2) is arranged in the upper section area of the reactor core, so that the heat pipe (2) can well operate at a proper temperature, and the heat pipe (2) is prevented from being damaged due to overheating; a single-layer container (4) is adopted between the heat pipe (2) and the fuel (1), and vacuumizing or helium filling is not needed in the operation process, so that the operation mode of the reactor can be greatly simplified, and the reliability of the system is improved.

Description

A dual-mode reactor core

technical field

The invention belongs to the technical field of dual-mode reactors, and in particular relates to a dual-mode reactor core.

Background technique

Dual-mode space nuclear reactors have the functions of propulsion and power generation at the same time, combining many advantages of nuclear thermal propulsion reactors and space reactor power sources over conventional energy sources. The reactor is very suitable for manned moon landing, manned Mars, space transportation and other missions. The United States, Russia and other space powers have carried out extensive research on dual-mode reactors and proposed many reactor solutions.

Michael G.Houts of the United States mentioned a dual-mode reactor scheme ALERT based on a heat pipe reactor in the document "Alert-derivative bimodal space powerand propulsion systems". The core structure is shown in Fig. 4, Fig. 5 and Fig. 6. This scheme adopts circular plate-shaped uranium carbide fuel, and the active area of the core is formed by stacking multiple fuel plates, and tungsten plates are arranged between the fuel plates for To enhance the radial heat conduction capacity, many axial hydrogen flow channels are set in the fuel and tungsten plates. There are many heat pipes arranged in the center hole and the periphery of the active area. The working medium of the heat pipe is sodium, and the cladding material is niobium. There are two layers of containers between the fuel and the heat pipes, and a certain gap is left between the containers. The dual-mode reactor has two modes of operation: propulsion mode and generation mode. In propulsion mode, hydrogen flows from top to bottom through the fuel and the hydrogen flow channel in the tungsten plate, and after being heated, it is ejected from the bottom through the nozzle to generate thrust. At this time, there is a vacuum between the two layers of containers to weaken the fuel and The heat transfer performance between the heat pipes prevents the heat pipes from being damaged due to overheating; in the power generation mode, the discharge of hydrogen is stopped, and the core heat is exported from the heat pipes to generate electricity outside the reactor. At this time, helium is filled between the two layers of containers to strengthen the fuel. The heat transfer performance between heat pipes.

There are deficiencies in this dual-mode reactor scheme, and the analysis is as follows: a two-layer container is set between the fuel and the heat pipe. In the propulsion mode, the space between the containers needs to be vacuumed to reduce heat transfer to protect the heat pipe; Injection of helium is required to enhance heat transfer. This switching increases the complexity of the system and reduces the reliability of the system.

Contents of the invention

Based on the analysis of the inadequacies of the ALERT dual-mode reactor scheme in the background technology, the present invention is dedicated to proposing an improvement scheme, which simplifies the heat transfer mode between the fuel and the heat pipe and simplifies the system operation on the premise of ensuring the safety of the heat pipe mode to improve system reliability.

In order to achieve the above purpose, the technical solution adopted by the present invention is a dual-mode reactor core, which includes several annular plate-shaped fuels, and the fuel is stacked to form a cylindrical core active area with a through hole in the axial position, The fuel is provided with a number of hydrogen flow channels, wherein a single-layer container is provided on the outside of the core active area and the inside of the through hole, and a single-layer container is provided on the side of the single-layer container that is not close to the fuel. There are heat pipes.

Furthermore, both sides of the single-layer container are in good contact with the fuel and the heat pipe respectively, and a heat collector is also arranged between the heat pipe and the single-layer container.

Further, the heat pipe is parallel to the axis of the active zone of the core, and the bottom end of the heat pipe extends to the upper region of the active zone of the core.

Further, it also includes a reflective layer located on the periphery of the active area of the core where the heat pipe is arranged, and the material of the reflective layer is beryllium oxide, which is used to reflect fission neutrons to the fuel, thereby improving the fuel Reactivity; also includes several control drums arranged in the reflective layer, the control drums are cylindrical and parallel to the axis of the core active area, the main body of the control drum is a reflector, and the reflector The material of the body is beryllium oxide, and part of the side surface of the control drum is provided with a neutron absorber, the neutron absorber is boron carbide, and the neutron absorber is used to absorb the neutrons diffused by fission in the fuel; When the neutron absorber faces the fuel with the rotation of the control drum, the reactivity in the fuel can be reduced; when all the neutron absorbers on the control drum face the fuel If the above-mentioned fuel is used, the reactor is shut down, otherwise, the reactor is turned on; a multi-layer foil insulation material is arranged between the heat pipe and the reflective layer to reduce the leakage loss of core heat.

Further, the fuel is a high temperature resistant fuel, including uranium carbide fuel, (U,Zr)C and CERMET fuel.

Further, the working fluid used by the heat pipe is sodium or lithium, and the cladding material of the heat pipe is niobium, molybdenum, molybdenum-rhenium alloy or tungsten-rhenium alloy.

Further, tungsten plates are arranged between each fuel.

Further, the hydrogen flow channel is parallel to the axis of the active zone of the core.

Further, the material of the single-layer container is tungsten-rhenium alloy.

Further, the material of the heat collector is niobium, molybdenum, molybdenum-rhenium alloy or tungsten-rhenium alloy.

The beneficial effects of the present invention are:

1. In the propulsion mode, hydrogen flows through the hydrogen flow channel 3 from top to bottom, so the operating temperature of the fuel 1 in the upper section of the active zone of the core is relatively low. The present invention arranges the heat pipe 2 in the upper section of the core, It can make the heat pipe 2 operate at a suitable temperature, and ensure that the heat pipe 2 will not be damaged due to overheating.

2. In the ALERT scheme in the background technology, under the two modes of propulsion and power generation, the gap between the heat pipe 2 and the fuel 1 needs to be evacuated and filled with helium respectively, which makes the operation of the reactor complicated. , and reduces the reliability of the system. In contrast, the solution proposed by the present invention uses a single-layer container 4 between the heat pipe 2 and the fuel 1, and does not need to be vacuumed or filled with helium during operation, which greatly simplifies the operation mode of the reactor and improves the reliability of the system.

Description of drawings

Fig. 1 is the schematic diagram of the core active zone of a kind of dual-mode reactor core described in the specific embodiment of the present invention (does not comprise reflection layer 7 and control drum 6);

Fig. 2 is the schematic diagram of a kind of dual-mode reactor core described in the specific embodiment of the present invention;

Fig. 3 is a longitudinal sectional view of a dual-mode reactor core described in the specific embodiment of the present invention;

Fig. 4 is the schematic diagram of the core active zone of the ALERT dual-mode reactor core described in the background technology part of the present invention (does not include reflection layer 7 and control drum 6);

Fig. 5 is the schematic diagram of ALERT dual-mode reactor core described in the background technology part of the present invention;

Fig. 6 is the longitudinal sectional view of the ALERT dual-mode reactor core described in the background technology part of the present invention;

In the figure: 1-fuel, 2-heat pipe, 3-hydrogen flow channel, 4-single-layer container, 5-heat collector, 6-control drum, 7-reflecting layer, 8-tungsten plate, 9-double-layer container.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, a dual-mode reactor core provided by the present invention includes several annular plate-shaped fuel 1, and the fuel 1 is stacked to form a cylindrical core active area whose axis position is a through hole, and the fuel 1 Several hydrogen flow channels 3 are arranged on the top, and the hydrogen flow channels 3 are parallel to the axis of the core active area. A single-layer container 4 is arranged outside the active area of the core and inside the through hole, and a heat pipe 2 is arranged on the side of the single-layer container 4 not close to the fuel 1 .

Both sides of the single-layer container 4 are in good contact with the fuel 1 and the heat pipe 2 respectively, and a heat collector 5 is arranged between the heat pipe 2 and the single-layer container 4 to further enhance the heat transfer performance with the fuel 1 .

The heat pipe 2 is parallel to the axis of the active area of the core, and the bottom end of the heat pipe 2 extends to the upper area of the active area of the core, but not to the lower area of the active area of the core. The operating temperature of the fuel 1 in the upper area of the active area of the core is Relatively low, so that the heat pipe 2 will not be overheated and damaged.

As shown in Fig. 2 and Fig. 3, it also includes a reflective layer 7 located at the periphery of the active area of the core where the heat pipe 2 is arranged. The material of the reflective layer 7 is beryllium oxide, which is used to reflect fission neutrons to the fuel 1, thereby improving the fuel efficiency. Reactivity of 1; also includes several control drums 6 arranged in the reflection layer 7, the control drums 6 are cylindrical, parallel to the axis of the core active area, the main body of the control drums 6 is a reflector, and the material of the reflector is Beryllium oxide, part of the side surface of the control drum 6 is provided with a neutron absorber, the neutron absorber is boron carbide, and the neutron absorber is used to absorb the neutrons from fission and diffusion in the fuel 1; the neutron absorber rotates with the control drum 6 When facing the fuel 1, the reactivity in the fuel 1 can be reduced; when all the neutron absorbers on the control drum 6 face the fuel 1, the reactor is shut down; otherwise, the reactor is turned on.

A multi-layer foil insulation material (not shown in the figure) is arranged between the heat pipe 2 and the reflection layer 7 to reduce leakage loss of core heat.

Fuel 1 is high temperature resistant fuel, including uranium carbide fuel, U, ZrC and CERMET fuel.

The working fluid used by the heat pipe 2 is sodium or lithium, and the cladding material of the heat pipe 2 is niobium, molybdenum, molybdenum-rhenium alloy or tungsten-rhenium alloy.

Tungsten plates 8 are arranged between each fuel 1 to enhance radial heat conduction capability.

The material of the single-layer container 4 is tungsten-rhenium alloy.

The material of the heat collector 5 is niobium, molybdenum, molybdenum-rhenium alloy or tungsten-rhenium alloy.

Finally, the specific application of the present invention is further described:

The dual-mode reactor core has two modes of operation: propulsion mode and power generation mode.

In the propulsion mode, the hydrogen working fluid flows through the fuel 1 and the hydrogen flow channel 3 in the tungsten plate 8 from top to bottom, and after being heated, it is ejected from the bottom through the nozzle to generate thrust. At the same time, part of the heat of the core is transferred to the heat pipe 2 through the single-layer container 4 and the heat collector 5, and then transferred to the thermoelectric conversion system outside the stack by the heat pipe 2 to generate electric energy.

In the power generation mode, the thermal power of the core is relatively low, the hydrogen working medium will stop discharging, and the heat generated by the fuel 1 will be transferred to the heat pipe 2 through heat conduction, and then transferred to the external thermoelectric conversion system to generate electricity.

The device described in the present invention is not limited to the examples described in the specific implementation manner. Other implementation manners obtained by those skilled in the art according to the technical solution of the present invention also belong to the technical innovation scope of the present invention.

Claims (8)

1. A dual-mode reactor core comprises a plurality of annular plate-shaped fuels (1), the fuels (1) are stacked to form a cylindrical core active area with an axial position as a through hole, and a plurality of hydrogen flow channels (3) are arranged on the fuels (1), and the dual-mode reactor core is characterized in that: a single-layer container (4) is arranged on the outer side of the core active area and the inner side of the through hole, and a heat pipe (2) is arranged on one side, which is not close to the fuel (1), of the single-layer container (4); two sides of the single-layer container (4) are in good contact with the fuel (1) and the heat pipe (2) respectively, and a heat collector (5) is arranged between the heat pipe (2) and the single-layer container (4); the heat pipe (2) is parallel to the axis of the core active area, and the bottom end of the heat pipe (2) extends to the upper section area of the core active area.

2. The dual mode reactor core of claim 1, wherein: the reactor core is characterized by further comprising a reflecting layer (7) positioned at the periphery of the core active area provided with the heat pipe (2), wherein the reflecting layer (7) is made of beryllium oxide and is used for reflecting fission neutrons to the fuel (1) so as to improve the reactivity of the fuel (1); the reactor core is characterized by further comprising a plurality of control drums (6) arranged in the reflecting layer (7), the control drums (6) are cylindrical and parallel to the axis of the core active area, the main body of each control drum (6) is a reflector made of beryllium oxide, a neutron absorber is arranged on part of the side surface of each control drum (6), the neutron absorber is boron carbide and is used for absorbing neutrons generated by fission and diffusion in the fuel (1); when the neutron absorber faces the fuel (1) with the rotation of the control drum (6), the reactivity in the fuel (1) can be reduced; when the neutron absorbers on all the control drums (6) face the fuel (1), the reactor is shut down, otherwise, the reactor is opened; and a plurality of layers of foil heat insulation materials are arranged between the heat pipes (2) and the reflecting layer (7) so as to reduce the leakage loss of the heat of the reactor core.

3. The dual mode reactor core of claim 1, wherein: the fuel (1) is a high-temperature-resistant fuel, and the types of the fuel comprise uranium carbide fuel, (U, zr) C and CERMET fuel.

4. The dual mode reactor core of claim 1, wherein: the working medium adopted by the heat pipe (2) is sodium or lithium, and the cladding material of the heat pipe (2) is niobium, molybdenum-rhenium alloy or tungsten-rhenium alloy.

5. The dual mode reactor core of claim 1, wherein: tungsten plates (8) are arranged between the respective fuels (1).

6. The dual mode reactor core of claim 1, wherein: the hydrogen flow channel (3) is parallel to the axis of the core active area.

7. The dual mode reactor core of claim 1, wherein: the single-layer container (4) is made of tungsten-rhenium alloy.

8. The dual mode reactor core of claim 1, wherein: the heat collector (5) is made of niobium, molybdenum-rhenium alloy or tungsten-rhenium alloy.

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