KR102592765B1 - A device for reducing air bubbles in the fluid machinery of a nuclear power plant - Google Patents

Abstract

The present invention relates to a bubble reduction device for a nuclear power plant system fluid device. More specifically, it is installed at the front or rear end of the fluid device and removes bubbles contained in the fluid passing through the fluid device, thereby damaging the fluid device due to bubble bursting. This relates to a bubble reduction device for nuclear power plant system fluid devices that prevents and ensures stable system operation.
For this purpose, a housing having an inlet pipe and an outlet pipe formed at one end and the other end, respectively, through which fluid inflows and fluids discharges; and an induction chamber installed inside the housing and guiding the fluid introduced through the inflow pipe to the upper part of the housing, wherein the induction chamber is formed in a cylindrical shape with an outer diameter corresponding to the inner diameter of the housing, Characterized by comprising a body having an opening opening in the flow direction, and a guide vane formed along the circumference of the body and providing a conduit through which fluid flowing in through the opening is discharged in the circumferential direction of the body. Provides a bubble reduction device for nuclear power plant system fluid devices.

Description

{A device for reducing air bubbles in the fluid machinery of a nuclear power plant}

The present invention relates to a bubble reduction device for nuclear power plant system fluid equipment, and more specifically, to a nuclear power plant system that separates and removes air bubbles contained in the fluid, thereby preventing damage to the fluid equipment due to bubble bursting and enabling stable system operation. This relates to bubble reduction devices in power plant system fluid devices.

A nuclear power plant is a facility that uses the heat energy generated by nuclear fission of fuel to transfer heat to water passing through a steam generator to generate steam, and the generated steam operates a turbine and generator to obtain electrical energy. Nuclear power plants maintain the safety of nuclear power plants and prevent the spread of radioactive materials by ensuring that the reactor core, which holds nuclear fuel, and the reactor coolant system, which transfers heat energy generated from the reactor to the secondary side, are operated safely within the range of design standards. Facilities must be provided for this. To achieve this, nuclear power plants are equipped with an engineered safety facility system to safely stop the power plant in the event of an accident. The engineering safety facility system includes the containment system, emergency core cooling system, and passive auxiliary feedwater system.

Among the safety equipment systems, the passive auxiliary water supply system will be taken as an example and will be examined with reference to the attached FIG. 1. As an example of the passive auxiliary water supply system, Figure 1 shows a passive secondary condensation system of a light water reactor disclosed in Republic of Korea Patent No. 10-1022164. Referring to FIG. 1, the passive secondary condensation system of a conventional light water reactor includes a steam generator 10 that generates steam by heat of the nuclear reactor, a main engine 11 that supplies heat from the steam generator 10 to the turbine side, and a turbine. The main water supply pipe (12) through which the water condensed by heat exchange with the cooling water is recovered to the steam generator (10), and the steam supply pipe that branches off from the main engine (11) and blocks the steam supply to the turbine side when the reactor operation is stopped. The steam flowing in through (13) is condensed into water by heat exchange in the condenser (20) contained inside the passive condensation tank (30), and then condensed through the condensate water recovery pipe (14) connected to the outlet of the condenser (20). It is configured to merge water into the main water supply pipe 12, and a backflow prevention unit 40 is installed in the condensate water recovery pipe 14 to prevent backflow of condensed water.

Meanwhile, due to the characteristics of the power plant system described above, air bubbles are generated within the system due to various causes, and fluid devices such as pumps, valves, pipes, and orifices in the system are exposed to the risk of mechanical damage due to bubble bursting (cavitation). . The pump is designed to secure the effective suction head to prevent mechanical damage caused by bubble bursting, but safety is not considered in the design of driven devices such as piping, and they are exposed to the risk of mechanical damage, so there is no improvement measure. It is being demanded.

Republic of Korea Patent No. 10-1022164

The present invention was devised to solve the above problems, and the purpose of the present invention is to separate and remove bubbles in the fluid moving along the system of a nuclear power plant, so that the safety of system operation and the mechanical soundness of the fluid device can be maintained. The purpose is to provide a bubble reduction device for nuclear power plant system fluid devices.

In order to achieve the above object, the present invention includes a housing having an inlet pipe and an outlet pipe formed at one end and the other end, respectively, through which fluid inflows and fluids discharges; and an induction chamber installed inside the housing and guiding the fluid introduced through the inflow pipe to the upper part of the housing, wherein the induction chamber is formed in a cylindrical shape with an outer diameter corresponding to the inner diameter of the housing, Characterized by comprising a body having an opening opening in the flow direction, and a guide vane formed along the circumference of the body and providing a conduit through which fluid flowing in through the opening is discharged in the circumferential direction of the body. Provides a bubble reduction device for nuclear power plant system fluid devices.

At this time, the discharge pipe is formed at a position spaced downward from the top of the housing to form a clearance space in the upper inner part of the housing, and the housing is provided so that air bubbles formed in the fluid can be removed by creating a vacuum in the clearance space of the housing. It is desirable that a vacuum generating means is installed.

In addition, it is preferable that a membrane partition wall made of Teflon is further installed on the upper inner peripheral surface of the housing.

In addition, it is preferable that the pipe of the guide vane is divided into a plurality of pipes in the height direction of the guide vane.

The bubble reduction device for nuclear power plant system fluid equipment according to the present invention has the following effects.

The present invention can reduce air bubbles contained in the fluid moving through the power plant system by being installed in the piping at the front or rear end of the fluid device based on the fluid device of a nuclear power plant, and the fluid with reduced bubbles can be used to transport the fluid device. Since it can pass through, it is possible to maintain the mechanical soundness of the fluid equipment of the nuclear power plant system and has the effect of increasing system operation safety.

That is, the present invention creates a vortex in the flow of fluid through an induction chamber to effectively separate bubbles, and the bubbles separated through the induction chamber are adsorbed to a membrane partition made of Teflon or removed through a vacuum generating means. Bubbles contained in the fluid that has passed through the bubble reduction device of the invention can be effectively removed.

Figure 1 is a diagram showing the configuration of a passive auxiliary water supply system of a nuclear power plant.
Figure 2 is a diagram showing a state in which the bubble reduction device of the nuclear power plant system fluid device according to a preferred embodiment of the present invention is installed in the front pipe of the pump.
Figure 3 is a cross-sectional view showing a bubble reduction device for a nuclear power plant system fluid device according to a preferred embodiment of the present invention.
Figure 4a is a perspective view showing an induction chamber constituting a bubble reduction device for a nuclear power plant system fluid device according to a preferred embodiment of the present invention.
Figure 4b is a cross-sectional view showing an induction chamber constituting a bubble reduction device for a nuclear power plant system fluid device according to a preferred embodiment of the present invention.
Figure 5 is a diagram showing a membrane partition wall constituting a bubble reduction device for a nuclear power plant system fluid device according to a preferred embodiment of the present invention.

The terms or words used in this specification and claims are not to be construed limited to their ordinary or dictionary meanings, and the inventor can appropriately define the concept of terms in order to explain his or her invention in the best way. It must be interpreted based on the meaning and concept consistent with the technical idea of the present invention.

Hereinafter, a bubble reduction device (hereinafter referred to as 'bubble reduction device') of a nuclear power plant system fluid device according to a preferred embodiment of the present invention will be described with reference to the attached FIGS. 2 to 5.

As shown in FIG. 2, the bubble reduction device is installed in the front pipe of a fluid device, such as a pump (P), to reduce bubbles contained in the fluid moving toward the pump (P) and send them to the pump (P), Mechanical damage to fluid devices due to bubble bursting (cavitation) was prevented and system operation was ensured stably.

As shown in FIG. 3, the bubble reduction device includes a housing 100, an induction chamber 200, a membrane partition wall 300, and a vacuum generating means 400.

The housing 100 constitutes the exterior of the bubble reduction device and forms an internal space. An inflow pipe 110, which is a pipe through which fluid flows into the internal space, and an discharge pipe 120, a pipe through which fluid is discharged from the internal space, are formed at one end and the other end of the housing 100, respectively. At this time, the discharge pipe 120 is installed at a position spaced downward from the top of the housing 100. Accordingly, the highest water level of the inner space of the housing 100 corresponds to the highest point of the discharge pipe 120, and a clearance space S spaced apart from the upper surface of the housing 100 is formed at the upper part of the inner space of the housing 100. In addition, an upper through hole 130 that communicates with the inner space of the housing 100 is formed at the upper end of the housing 100, and the upper through hole 130 allows a vacuum generating means 400 to be described later to be connected to the inner space of the housing 100. It is designed to create a vacuum by generating negative pressure.

The induction chamber 200 guides the fluid flowing into the internal space through the inlet pipe 110 to the upper part of the housing 100, and guides the fluid while rotating in the circumferential direction along the inner circumferential surface of the housing 100. It creates a difference in flow velocity between the bubbles and water contained within it, effectively separating the bubbles from the fluid. The induction chamber 200 is preferably fixed to the inner space of the housing 100 and installed in the lower part of the housing 100. That is, when dividing the internal space of the housing 100 into upper and lower parts, it is preferable that the induction chamber 200 is fixed to the lower part of the internal space of the housing 100. The induction chamber 200 is preferably formed to have an outer diameter corresponding to the inner diameter of the housing 100, as shown in FIGS. 3 and 4A, and is preferably composed of a body 210 and a guide vane 220.

The body 210 of the induction chamber 200 is preferably provided in a cylindrical shape, and forms an opening 211 that opens toward the inflow pipe 110. That is, the body 210 in the preferred embodiment is formed in a hollow cylindrical shape that is opened downward. The guide vane 220 provides a conduit through which fluid flowing into the body 210 through the opening 211 can be discharged out of the housing 100, and is formed along the circumferential surface of the body 210. The guide vane 220 preferably provides a pipe rounded toward the circumference of the body 210 as shown in FIGS. 4A and 4B so that the fluid can be discharged while applying a rotational force in the circumferential direction of the body 210. do. Accordingly, the outer shape of the guide vane 220 is preferably formed to be rounded in one direction around the circumference of the body 210. Meanwhile, the guide vane 220 is preferably divided in the height direction of the body 210. That is, as shown in FIG. 4A, the guide vane 220 is configured so that the pipe through which the fluid exits is partitioned in the height direction of the body 210. At this time, it is preferable that the number of divided configurations of the guide vanes 220 is plural. As the guide vane 220 is divided in this way, the fluid flowing into the body 210 is not only rotated in the circumferential direction along the inner circumferential surface of the body 210, but is also discharged uniformly through the outlet of the guide vane 220. Rather, as it is discharged irregularly, a vortex is formed and rises, effectively separating the bubbles. In other words, this configuration of the induction chamber 200 can guide the fluid to the upper part of the internal space of the housing 100 while effectively separating water and air bubbles.

The membrane partition wall 300 collects bubbles of fluid guided to the upper part of the housing 100 through the induction chamber 200 and serves to reduce fluid bubbles from escaping the discharge pipe 120. As shown in FIGS. 3 and 5, the membrane partition wall 300 is preferably made of a hollow cylindrical shape with an open bottom, and is installed in the upper part of the inner space of the housing 100. At this time, the membrane partition wall 300 is preferably fixed in close contact with the inner peripheral surface of the housing 100, and the material of the membrane partition wall 300 is preferably Teflon. Teflon has the characteristic of effectively adsorbing air bubbles due to its material characteristics. Additionally, the membrane partition wall 300 may be formed as a mesh to increase the bubble adsorption rate. Meanwhile, a side hole 310 is formed on the outer peripheral surface of the membrane partition 300 to discharge fluid into the discharge pipe 120, and the diameter of the side hole 310 corresponds to the diameter of the discharge pipe 120. Additionally, an upper hole 320 is formed on the upper surface of the membrane barrier wall 300 to create a vacuum inside the membrane barrier wall 300. The upper hole 320 is configured for connection with the vacuum generating means 400, which will be described later.

The vacuum generating means 400 creates a vacuum in the upper part of the internal space of the housing 100, that is, the clearance space S of the membrane partition wall 300, and filters out air bubbles formed in the clearance space S of the membrane partition wall 300. It plays a role. That is, the vacuum generating means 400 generates negative pressure inside the membrane partition wall 300 to remove bubbles in the fluid induced into the upper part of the housing 100 through the induction chamber 200. As shown in FIG. 3, the vacuum generating means 400 is preferably composed of a suction pipe 410 and a vacuum pump 420. The suction pipe 410 is connected to the upper hole 320 of the membrane partition 300 through the upper hole 130 of the housing 100, and the vacuum pump 420 is inside the membrane partition 300 through the suction pipe 410. Negative pressure is generated to remove air bubbles.

Hereinafter, we will look at the operation of the bubble reduction device configured as described above.

The pump (P) operates to move fluid to the nuclear power plant system, and the fluid passes through a bubble reduction device before passing through the pump (P). The fluid moves through the inlet pipe 110 of the bubble reduction device and is then guided to the upper part of the internal space of the housing 100 through the induction chamber 200 of the housing 100. At this time, the fluid flows into the induction chamber 200 through the opening 211 of the induction chamber 200, and the fluid rotates in the circumferential direction of the induction chamber 200 inside the induction chamber 200, forming a vortex. . In this process, the fluid flows out of the induction chamber 200 through the guide vane 220, which is divided into multiple stages. At this time, the fluid forms a vortex (vortex) inside the induction chamber 200 and flows out irregularly through the guide vane 220 located at the bottom and the guide vane 220 located at the top, causing the fluid contained in the fluid to flow out. As the bubbles are effectively separated, the fluid moves to the upper part of the internal space of the housing 100.

The bubbles separated from the fluid are collected in the membrane partition 300, and the fluid from which the bubbles are separated is moved to the discharge pipe 120 through the side hole 310 of the membrane partition 300. The air bubbles collected and separated from the fluid in the membrane partition wall 300 are removed from the inside of the membrane partition wall 300 as they exit through the suction pipe 410 by generating negative pressure of the vacuum pump 420.

As explained so far, the bubble reduction device in the nuclear power plant system fluid device according to the present invention effectively separates the bubbles contained in the fluid before or after the fluid moving in the nuclear power plant system passes through the fluid device, thereby reducing the risk of bubble bursting. Damage to fluid devices was prevented and stable system operation was achieved.

Although the present invention has been described in detail with respect to the described embodiments above, it is obvious to those skilled in the art that various changes and modifications are possible within the technical scope of the present invention, and such changes and modifications naturally fall within the scope of the appended patent claims.

100: Housing 110: Inlet pipe
120: Discharge pipe 130: Upper through hole
200: Induction chamber 210: Body
211: opening 220: guide vane
300: Membrane partition wall 310: Side hole
320: Upper hole 400: Vacuum generating means
410: Suction pipe 420: Vacuum pump

Claims (4)

A housing having an inlet pipe and an outlet pipe formed at one end and the other end, respectively, through which fluid inflows and fluids discharges; and
It is installed inside the housing and includes an induction chamber that guides the fluid introduced through the inflow pipe to the upper part of the housing,
The induction chamber is,
It is formed in a cylindrical shape with an outer diameter corresponding to the inner diameter of the housing, and has a body having an opening that opens toward the direction in which the fluid flows, and is formed along the circumference of the body, and the fluid flowing in through the opening moves in the circumferential direction of the body. It includes a guide vane that provides a pipe discharged to,
The discharge pipe is formed at a position spaced downward from the top of the housing to form a clearance space in the upper inner part of the housing,
A vacuum generating means is installed in the housing to remove air bubbles formed in the fluid by creating a vacuum in the clearance space of the housing,
A membrane partition wall made of Teflon is installed on the upper inner peripheral surface of the housing,
A bubble reduction device for a nuclear power plant system fluid device, characterized in that the pipe of the guide vane is divided into a plurality of parts in the height direction of the guide vane.







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