CN212010380U

CN212010380U - Heat pipe type passive temperature controller for secondary shielding water tank

Info

Publication number: CN212010380U
Application number: CN201921938352.6U
Authority: CN
Inventors: 程建杰; 陶汉中; 李维; 李强
Original assignee: Nanjing Tech University
Current assignee: Nanjing Tech University
Priority date: 2019-11-11
Filing date: 2019-11-11
Publication date: 2020-11-24
Anticipated expiration: 2029-11-11

Abstract

A heat pipe type passive temperature controller for a secondary shielding water tank belongs to the technical field of heat dissipation of nuclear power devices. The invention mainly utilizes two times of simple phase changes in the closed space of the heat pipe to absorb heat generated by the electronic element, and combines various heat transfer modes of heat conduction, natural convection and forced convection to efficiently and stably discharge the heat out of the secondary shielding water tank. The temperature controller mainly comprises a condensation branch pipe (1), fins (2), an upper header pipe (3), an ascending pipe (4), a descending pipe (5), a steam distributor (6), a liquid collector (7), a flow guide air duct (8), a circulating fan (9), a condensation section shell (10), a connecting bent pipe (11), a lower header pipe (12) and a gasification branch pipe (13). The invention takes the heat pipe as the main heat conducting element, effectively solves the problems of unstable active circulation and work of the traditional coil heat exchange device, and fully ensures the normal operation of the nuclear reactor and the relative stability of the temperature in the water shielding layer.

Description

Heat pipe type passive temperature controller for secondary shielding water tank

Technical Field

The invention relates to a secondary shielding water tank heat pipe type passive temperature controller using a heat pipe as a heat conducting element, and belongs to the technical field of heat dissipation of nuclear power devices.

Background

Today, the development of nuclear power is becoming rapid and more nuclear power plants are used in various fields. For marine power plants, nuclear reactors have some incomparable advantages with other plants, such as good concealment, high endurance, high power, etc. However, since nuclear reactors are potentially radioactive, it is necessary to provide a protective shield to protect crew and the surrounding environment from radioactive hazards. In a reactor shield cooling system, a ring-by-ring structure of lead layer-shield water-lead layer (secondary shield water tank) is generally used, and the inside and outside lead layer and the secondary shield water layer reduce neutrons and radiation leaking out of the core to allowable levels and take away heat of the core. This results in a gradual increase in the temperature of the water shield, producing either undercooling or saturation boiling, which reduces the effect of shielding nuclear radiation. Therefore, it is becoming more and more urgent to develop a secondary shield water tank temperature controller.

At present, in most secondary shielding water tanks, a coil pipe which is arranged in advance is adopted to carry out cooling water circulation so as to take away heat. However, with the development of science and technology and the improvement of automation, the internal structure of the secondary shielding water tank becomes more and more complex, which brings many problems to the design, installation and maintenance of the coil heat dissipation device. Meanwhile, the heat dissipation device is in active circulation and has a certain difference with the passive safety device. The invention adopts the heat pipe as the heat transfer device, the heat pipe is a high-efficiency heat conduction element which realizes passive heat transfer by two times of simple phase change in a closed space, and the defect of active circulation of the coil pipe heat dissipation device is overcome. Because the heat pipes are relatively independent, even if a single heat pipe fails, the normal work of other heat pipes cannot be influenced, and the working reliability is higher. In addition, the heat pipe has simple structure and is very convenient to install and maintain. Therefore, the heat pipe type passive temperature controller realizes efficient and stable heat dissipation, and effectively ensures the normal operation of the nuclear reactor and the relative stability of the temperature in the water shielding layer.

Disclosure of Invention

The invention provides a secondary shielding water tank temperature controller consisting of a special-shaped heat pipe and an air cooling system, which comprises a condensation branch pipe (1), fins (2), an upper header pipe (3), an ascending pipe (4), a descending pipe (5), a steam distributor (6), a liquid collector (7), a flow guide air channel (8), a circulating fan (9), a condensation section shell (10), a connecting bent pipe (11), a lower header pipe (12) and a gasification branch pipe (13).

Go up header pipe (3) and link together tedge (4), downcomer (5) and condensation branch pipe (1) of taking fin (2) and constitute the condensation segment, be in the tilt state during condensation branch pipe (1) installation, be favorable to the condensate to collect, fin (2) have been arranged outward in condensation branch pipe (1) for strengthen the heat exchange with the air, diversion air duct (8) and circulating fan (9) have been arranged outward in the condensation segment, when the natural convection current of air can satisfy the heat dissipation requirement, the fan is closed. The lower header pipe (12) connects the gasification branch pipes (13) together to form an evaporation section, and the gasification branch pipes (13) are arranged in parallel, can be arranged in a single layer or in multiple layers. The tube may have smooth wall or may be provided with porous material to homogenize the liquid film and strengthen the gasifying process. The condensation section and the evaporation section are connected through a connecting bent pipe (11). The invention provides two schemes of a single pipe and a double pipe, wherein the single pipe scheme is that an ascending pipe (4) and a descending pipe (5) are arranged in a sleeve mode, the number of holes formed in a shielding partition plate can be reduced, and the double pipe scheme is that the ascending pipe (4) and the descending pipe (5) are respectively arranged.

The secondary shielding water tank absorbs heat generated by a nuclear reactor to heat a shielding water layer, the gasification branch pipes (13) absorb the heat of the shielding water layer, the heat is transferred to a condensation section through the lower header pipe (12) and the ascending pipe (4), the steam distributor (6) in the upper header pipe (3) distributes steam in the ascending pipe to each condensation branch pipe (1), the steam emits heat in the condensation branch pipes (1) and radiates the heat to the periphery through the fins (2), and finally the heat is guided out to the external environment through the diversion air duct (8) through the circulating fan (9). The vapor condenses into liquid in the condensation branch pipe (1), collects into a liquid collector (7) under the action of gravity and returns to the evaporation section again through a downcomer (5).

Drawings

Figure 1 is a detailed block diagram of the condenser section in a double tube scheme.

The names of the reference numbers in fig. 1 are: 1. a condensing branch pipe; 2. a fin; 3. an upper header pipe; 4. a riser pipe; 5. a down pipe; 6. A steam distributor; 7. a liquid collector.

Figure 2 is a detailed block diagram of the evaporator end of the double tube scheme.

The reference numbers in fig. 2 are: 12. a lower header pipe; 13. and (4) gasifying the branch pipe.

Fig. 3 is a schematic diagram of a dual tube scheme.

The reference numbers in fig. 3 refer to: 8. a diversion air duct; 9. a circulating fan; 10. a condenser section shell; 11. and connecting the bent pipe.

Fig. 4 is a schematic diagram of a single tube arrangement.

The reference numbers in fig. 4 are: 8. a diversion air duct; 9. a circulating fan; 10. a condenser section shell; 11. and connecting the bent pipe.

Detailed description of the preferred embodiments

As shown in fig. 3, the heat pipe type passive temperature controller for the secondary shielded water tank mainly comprises a condensation branch pipe (1), fins (2), an upper header pipe (3), an ascending pipe (4), a descending pipe (5), a steam distributor (6), a liquid collector (7), a flow guide air duct (8), a circulating fan (9), a condensation section shell (10), a connecting bent pipe (11), a lower header pipe (12) and a gasification branch pipe (13).

Wherein go up header pipe (3) and link together tedge (4), downcomer (5) and condensation branch pipe (1) of taking fin (2) and constitute the condensation segment, be in the tilt state during condensation branch pipe (1) installation, be favorable to the condensate to collect, fin (2) have been arranged outward to condensation branch pipe (1) for strengthen the heat exchange with the air, diversion wind channel (8) and circulating fan (9) have been arranged outward to the condensation segment, when the air natural convection can satisfy the heat dissipation requirement, the fan is closed. The lower header pipe (12) connects the gasification branch pipes (13) together to form an evaporation section, and the gasification branch pipes (13) are arranged in parallel, can be arranged in a single layer or in multiple layers. The tube may have smooth wall or may be provided with porous material to homogenize the liquid film and strengthen the gasifying process. The condensation section and the evaporation section are connected through a connecting bent pipe (11).

The working principle of the invention is as follows: the secondary shielding water tank absorbs heat generated by a nuclear reactor to heat a shielding water layer, the gasification branch pipes (13) absorb the heat of the shielding water layer, the heat is transferred to a condensation section through the lower header pipe (12) and the ascending pipe (4), the steam distributor (6) in the upper header pipe (3) distributes steam in the ascending pipe to each condensation branch pipe (1), the steam emits heat in the condensation branch pipes (1) and radiates the heat to the periphery through the fins (2), and finally the heat is guided out to the external environment through the diversion air duct (8) through the circulating fan (9). The vapor condenses into liquid in the condensation branch pipe (1), collects into a liquid collector (7) under the action of gravity and returns to the evaporation section again through a downcomer (5).

According to the invention, the heat of the secondary shielding water layer is rapidly led out by utilizing two times of simple phase changes in the heat pipe closed space, and the heat is efficiently and stably discharged out of the secondary shielding water tank by matching with an air cooling system, so that the problems of unstable active circulation and work of the traditional coil heat exchange device are effectively solved. The invention takes the heat pipe as a main heat conducting element, thereby effectively ensuring the normal operation of the nuclear reactor and the relative stability of the temperature in the water shielding layer.

Claims

1. The utility model provides an active temperature controller of secondary shield water tank heat pipe formula non-which characterized in that:

the device comprises a condensation branch pipe (1), fins (2), an upper header pipe (3), an ascending pipe (4), a descending pipe (5), a steam distributor (6), a liquid collector (7), a flow guide air duct (8), a circulating fan (9), a condensation section shell (10), a connecting bent pipe (11), a lower header pipe (12) and a gasification branch pipe (13);

go up header pipe (3) and link together tedge (4), downcomer (5) and condensation branch pipe (1) of taking fin (2) and constitute the condensation zone, lower header pipe (12) link together each gasification branch pipe (13) and have constituted the evaporation zone, gasification branch pipe (13) are parallelly connected to be arranged, can arrange with the multilayer by the individual layer and arrange, and condensation zone and evaporation zone pass through connecting bend (11) and link to each other.

2. The heat pipe type passive temperature controller of the secondary shielded water tank of claim 1, wherein:

the gasification branch pipe (13) absorbs heat, the heat is transferred to the upper header pipe (3) through the lower header pipe (12) and the ascending pipe (4), the upper header pipe (3) transfers the heat to each condensation branch pipe (1) by utilizing the steam distributor (6), the condensation branch pipes (1) radiate the heat to the periphery through the fins (2), and finally the heat is led out to the external environment through the diversion air duct (8) through the circulating fan (9).

3. The heat pipe type passive temperature controller of the secondary shielded water tank of claim 1, wherein:

the condensation branch pipe (1) is obliquely installed, and fins (2) are arranged outside the condensation branch pipe (1).

4. The heat pipe type passive temperature controller of the secondary shielded water tank of claim 1, wherein:

the inner wall of the gasification branch pipe (13) is provided with two arrangement methods of a smooth wall surface and a porous material, and the porous material is used for strengthening the gasification branch pipe (13) to absorb heat.

5. The heat pipe type passive temperature controller of the secondary shielded water tank of claim 1, wherein:

the connection mode of the ascending pipe (4) and the descending pipe (5) has a single-pipe scheme and a double-pipe scheme, the single-pipe scheme is that the ascending pipe (4) and the descending pipe (5) are arranged in a sleeve mode, and the double-pipe scheme is that the ascending pipe (4) and the descending pipe (5) are respectively arranged.

6. The heat pipe type passive temperature controller of the secondary shielded water tank of claim 1, wherein:

and a diversion air duct (8) and a circulating fan (9) are arranged in the condensation section shell (10) and are used for meeting the heat dissipation requirement.