JP2010043969A - Steam separator, and boiling water reactor equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steam separator capable of reducing a pressure loss, while keeping high steam separation performance, and a boiling water reactor equipped with the steam separator and having improved reactor power and cost benefit. <P>SOLUTION: This steam separator having a multistage constitution, by connecting at least the second stage steam separation part 4 over a first stage steam separation part 3 is equipped with a hub 9 formed in a rod shape as a diffuser 6 or a swirler 12 provided in the first stage inner cylinder 7 and arranged on the center of the first stage inner cylinder 7; the first swirl vane 8 for imparting a centrifugal force to the outer peripheral part of a vapor-liquid mixture flow flowing inside the first stage inner cylinder 7; and the second swirl vane 10 for imparting centrifugal force to the inner peripheral part. The second swirl vane 10 is constituted so as to impart a larger centrifugal force to the vapor-liquid mixture flow than the centrifugal force imparted to the vapor-liquid mixture flow by the first swirl vane 8. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a steam separator for separating cooling water from a gas-liquid mixed flow generated in a nuclear reactor, and a boiling water reactor in which a reactor core and a plurality of steam separators are arranged in a reactor pressure vessel.

  In a nuclear power plant, in order to maintain the soundness of the turbine by eliminating the erosion and corrosion phenomenon in the steam turbine blade part, an air-water separator that separates the cooling water from the gas-liquid mixed flow generated by the heat generation of the core, and the separation A steam-water separation system configured with a steam dryer that removes droplets contained in the generated steam is used, and the amount of droplets contained in the steam is set to a predetermined value or less to be supplied to the steam turbine.

  FIG. 5 is a diagram showing an example of an improved boiling water reactor using a steam / water separator. The reactor pressure vessel 101 is filled with cooling water up to a predetermined level, and the core 103 is placed in the shroud 102. Is installed. Steam generated by heat generation in the core 103 is mixed with cooling water through the upper plenum 104 and flows into the steam-water separator 1 installed in a large number on the shroud head 105 by the standpipe 2 and contains steam containing droplets. Separated into cooling water.

  The steam containing the droplets is removed by the steam dryer 106 and then supplied to a steam turbine (not shown) via the main steam pipe 107 to drive the generator.

  At this time, the droplets removed by the steam dryer 106 are returned to the cooling water below from between the steam dryer skirt 108 and the reactor pressure vessel 101. On the other hand, the steam used to drive the generator is condensed by a condenser (not shown), heated by a feed water heater, and then returned as feed water from the feed water pipe 109 into the reactor pressure vessel 101.

  The cooling water separated by the steam separator 1 is mixed with the feed water supplied from the feed water pipe 109 and then descends in the downcomer 110 and is given kinetic energy by the internal pump 111 to pass through the lower plenum 112. It is recirculated to the core 103 via.

  By the way, the steam-water separator 1 applied to the boiling water reactor uses a steam-water separator having a multi-stage structure, so that necessary steam-water separation performance can be ensured. (For example, refer to Patent Document 1). In this multi-stage steam / water separator, steam / water separation is generally performed as follows.

  The gas-liquid mixed flow of steam and cooling water generated in the nuclear reactor flows into the stand pipe located at the lower end of the steam separator, and then the hub disposed in the diffuser connected to the upper end of the stand pipe and its By passing through a swirler composed of a plurality of swirl blades fixedly installed around, a centrifugal force is applied to form a swirl flow. Further, the gas-liquid mixed flow that has become a swirling flow flows into the first stage inner cylinder connected to the upper end of the diffuser, and the cooling water having a high density forms a liquid film on the outer peripheral side to form a droplet on the center side. Separated from the vapor containing. The separated steam passes through the inside of the first stage pick-off ring, and most of the liquid film passes through the outside of the first stage pick-off ring and is drained to the outside by the first stage outer cylinder.

  The steam containing droplets that have passed through the first stage pick-off ring has a centrifugal force and flows into the second stage steam-water separator having the same configuration as that of the first-stage steam-water separator. Droplets are separated from the steam and drained to the outside. Thus, the conventional steam separator is configured to install the steam / water separator in multiple stages so that the necessary steam / water separation performance can be ensured.

  On the other hand, in recent years, in order to increase the amount of power generation while ensuring the thermal margin of the reactor core, the pressure loss is reduced with respect to the steam separator disposed in the cooling water recirculation path. It is requested.

As a known technique for reducing the pressure loss of the steam / water separator, there is no diffuser between the stand pipe and the first stage inner cylinder, and pressure is set by installing a swirler in the first stage inner cylinder having a relatively low flow rate. Those that reduce the loss (for example, see Patent Document 2), those that provide a swirler in the first-stage cylinder and reduce the hub diameter to significantly reduce the pressure loss (for example, see Patent Document 3). In addition, there are those that define the dimensions and shapes such as the hub diameter and the outlet angle of the swirler swirl blade that can reduce the pressure loss while maintaining the gas-liquid separation performance (see, for example, Patent Document 4).
JP-A-10-197678 Japanese Utility Model Publication No. 8-1361 JP 2000-153118 A JP 2003-114293 A

  However, since the technique disclosed in Patent Document 2 is intended for a steam generator of a pressurized water reactor and is not configured to include a diffuser or a stand pipe with a small diameter, a boiling water reactor or an improved boiling water atom It cannot be applied to the furnace. The technique disclosed in Patent Document 3 can reduce pressure loss as the hub diameter is reduced and the outlet angle of the swirler blades is reduced. However, on the other hand, the centrifugal force applied to the gas-liquid mixed flow is reduced. Since it becomes small, air-water separation performance falls. Furthermore, since the technique disclosed in Patent Document 4 is intended to maintain the gas-liquid separation performance and reduce the pressure loss while maintaining the hub diameter at a certain size or more, the hub diameter can be reduced. It is difficult and there is room for improvement in reducing pressure loss by reducing the hub diameter.

  The present invention has been made in view of the situation of the prior art as described above, and a first object of the present invention is to reduce the gas-liquid separation performance while further reducing the pressure loss by reducing the hub diameter. It is to enable suppression.

  In addition, the second object of the present invention is to reduce the pressure loss of the steam separator and maintain high steam / water separation performance to improve the reactor power and improve the economic efficiency. To provide a furnace.

  In order to achieve the first object, according to the present invention, firstly, a plurality of stages of steam-water separators are arranged along the flow direction of the gas-liquid mixed flow, and the first arranged at the most upstream side. The stage air-water separator is disposed below the first stage inner cylinder connected to the upper end of the standpipe via a diffuser and a centrifugal force is applied to the gas-liquid mixed flow. A swirler that forms a liquid film on the inner surface of the first stage inner cylinder with the liquid separated from the gas-liquid mixed flow; and an inner surface of the first stage inner cylinder that is disposed above the first stage inner cylinder. The first stage pick-off ring that separates the liquid film formed from the gas-liquid mixed flow and the first stage inner cylinder is disposed so as to surround the first stage outer cylinder, and the first stage outer cylinder is disposed between the first stage outer cylinder and the first stage outer cylinder. From the first stage outer cylinder constituting the first stage drainage flow path for discharging the liquid film separated from the gas-liquid mixed flow by the stage pick-off ring In the steam separator, the swirler is formed in a rod-like shape, and a hub disposed at the center of the first stage inner cylinder and a peripheral part of the gas-liquid mixed flow flowing inside the first stage inner cylinder are centrifuged. A first swirl vane that applies force and a second swirl vane that imparts centrifugal force to the inner peripheral portion, and the second swirl vane has a larger centrifugal force than the centrifugal force that the first swirl vane imparts to the gas-liquid mixed flow. The force was applied to the gas-liquid mixed flow.

  According to this configuration, since the hub is formed in a rod shape, the hub diameter can be reduced to the minimum, and the pressure loss of the gas-liquid separator can be reduced to the maximum. In addition, the swirler includes the first and second swirl vanes, and the centrifugal force that the second swirl vane imparts to the gas-liquid mixed flow is greater than the centrifugal force that the first swirl vane imparts to the gas-liquid mixed flow. Cooling water contained in the central part of the liquid mixture flow can be efficiently directed to the inner surface of the first stage inner cylinder, and a liquid film can be formed on the inner surface of the first stage inner cylinder, thus achieving high air-water separation. Performance can be demonstrated.

  Secondly, in the first steam separator, the swirler includes a hub formed in a rod shape, a cylindrical body arranged concentrically on the outer periphery of the hub, and the cylindrical body. The first swirl vane is formed on the outer surface, and the second swirl vane is formed between the outer surface of the hub and the inner surface of the cylindrical body.

  According to this configuration, since the cylindrical body is provided on the outer periphery of the second swirl vane, the first swirl blade can be easily attached to the hub and the second swirl vane, and the swirler can be easily manufactured. it can.

  Thirdly, according to the present invention, in the first steam separator, the swirler includes a hub formed in the rod shape, a second swirling blade formed on an outer surface of the hub, and a second swirling blade. The first swirl vane is formed outward from the tip.

  According to this configuration, since the cylindrical body is not provided, the pressure loss of the gas-liquid separator can be reduced as compared with the case where the cylindrical body is provided, and the first swirl blade side from the flow path on the second swirl blade side. Since the movement of the gas-liquid mixed flow into the flow path becomes easy, gas-liquid separation can be promoted.

  Fourthly, according to the present invention, in the first to third air / water separators, a tip end of the first swirl vane is joined to an inner surface of the first stage inner cylinder.

  According to this configuration, since the swirler is provided on the inner surface of the first stage inner cylinder having the same diameter as the large diameter portion of the diffuser, the pressure loss of the gas-liquid separator can be reduced as compared with the case where the swirler is provided in the diffuser. Can do.

  According to the fifth aspect of the present invention, in the first to third air / water separators, the tip of the first swirl vane is joined to the inner surface of the diffuser.

  According to this configuration, since the swirler is provided in the diffuser, it is easy to apply a centrifugal force to the gas-liquid mixed flow, and high steam / water separation performance can be achieved, and the swirler can be made smaller and lighter. The seismic resistance of the separator can be increased.

  Sixthly, in the first to fifth steam separators according to the present invention, the hub has a small radius of curvature at the upstream end with respect to the flow direction of the gas-liquid mixed flow, and the hub at the downstream end. The configuration is such that it has a streamlined shape with a large radius of curvature.

  According to this configuration, since the rod-shaped hub is formed in a streamline shape, the hub hardly becomes a resistance factor of the gas-liquid mixed flow, and the pressure loss of the gas-liquid separator can be reduced.

  Seventh, the present invention provides a reactor pressure vessel in which cooling water is filled to a predetermined water level, a core installed in the shroud, a gas-liquid mixed flow generated by heat generation of the core, and steam containing droplets and cooling In a boiling water reactor comprising a steam-water separator that separates into water and a steam dryer that removes droplets from steam containing droplets separated by the steam-water separator, the steam-water separator As described above, a plurality of stages of steam / water separation sections are arranged along the flow direction of the gas-liquid mixed flow, and the first stage steam / water separation section disposed on the most upstream side is connected to the upper end of the stand pipe via the diffuser. A cylindrical first-stage inner cylinder connected to the first-stage inner cylinder, the first-stage inner cylinder being disposed below the first-stage inner cylinder, applying a centrifugal force to the gas-liquid mixed flow, and the liquid separated from the gas-liquid mixed flow A swirler that forms a liquid film on the inner surface of the inner cylinder, and an inner surface of the first inner cylinder that is disposed above the first inner cylinder. The first stage pick-off ring that separates the formed liquid film from the gas-liquid mixed flow and the first stage outer cylinder are disposed so as to surround the first stage outer cylinder, and the first stage outer cylinder is disposed between the first stage outer cylinder and the first stage outer cylinder. A first-stage outer cylinder constituting a first-stage drainage channel for discharging a liquid film separated from the gas-liquid mixed flow by a pick-off ring, and the swirler is formed in a rod shape, A hub disposed at the center of the cylinder, a first swirl vane that applies centrifugal force to the outer peripheral part of the gas-liquid mixed flow that flows inside the first stage inner cylinder, and a second swirl vane that applies centrifugal force to the inner peripheral part The second swirl vane is configured to include a component that applies a centrifugal force to the gas-liquid mixed flow larger than the centrifugal force that the first swirl vane imparts to the gas-liquid mixed flow.

  As described above, since the steam-water separator according to the present invention has a hub-like shape, the hub diameter can be reduced to the minimum, the pressure loss of the gas-liquid separator can be reduced to the maximum, and the swirler can be reduced. The first and second swirl vanes have a centrifugal force applied to the gas-liquid mixed flow by the second swirl blades greater than the centrifugal force imparted to the gas-liquid mixed flow by the first swirl vane. The cooling water contained in the central portion of the first can be efficiently directed toward the inner surface of the first stage inner cylinder, and high steam-water separation performance can be exhibited. Therefore, the boiling water reactor equipped with this steam separator can increase the flow rate of the steam-water mixed flow, and can improve the output and the economy.

  The air / water separator according to the invention has a hub formed in a rod shape, and a swirler having first and second swirl vanes, and the second swirl vanes generate centrifugal force applied to the gas-liquid mixed flow by the first swirl vanes. Since it is larger than the centrifugal force applied to the liquid mixture flow, the pressure loss of the gas-liquid separator can be reduced, and high gas-water separation performance can be exhibited.

  The boiling water reactor of the present invention forms a swirler hub provided in a steam separator into a rod shape, and includes a swirler with first and second swirl vanes, and the second swirl vanes are in a gas-liquid mixed flow. Since the centrifugal force to be applied is made larger than the centrifugal force that the first swirl vane gives to the gas-liquid mixed flow, the pressure loss can be greatly reduced while maintaining the steam-water separation performance of the steam-water separator at a high level. It is possible to increase the flow rate of the gas-water mixed flow, thereby improving the output of the boiling water reactor and improving the economy.

  Hereinafter, a first embodiment of a steam-water separator and a boiling water reactor according to the present invention will be described with reference to FIG. FIG. 1 is an explanatory diagram of a steam separator according to the first embodiment. The boiling water reactor according to the first embodiment is obtained by applying the steam-water separator of FIG. 1 to the improved boiling water reactor shown in FIG.

  As shown in FIG. 1A, the steam / water separator 1 according to the first embodiment includes a first-stage steam / water separator 3, a second-stage steam / water separator 4, and a third-stage steam / water separator 5. It has a three-stage configuration consisting of The first-stage steam-water separation unit 3 includes a diffuser 6 that is installed on the shroud head 105 and connected to the upper end of the stand pipe 2 that communicates with the upper plenum 104 (see FIG. 5). A first stage inner cylinder 7 is connected to the upper end of the diffuser 6, and a plurality of first swirl vanes 8 are joined to the first stage inner cylinder 7. A swirler in which a spiral second swirl blade 10 shown in FIGS. 1B and 1C is joined to the first swirl blade via a cylindrical body 11 between the first swirl blade and the hub 9. 12 By providing the second swirl vane 10 inside the first swirl vane 8, further reducing the low pressure loss while maintaining the gas-liquid separation performance.

  A first-stage outer cylinder 14 is installed on the outer periphery of the first-stage inner cylinder 7 via a plurality of partition plates 13 arranged in the circumferential direction. A flow path is formed by the partition plate 13 between the first stage inner cylinder 7 and the first stage outer cylinder 14, and the lower end of the first stage outer cylinder 14 opens downward.

  The second stage steam-water separation unit 4 includes a second stage inner cylinder 16, a second stage outer cylinder 17, and a second stage pick off ring 18 assembled on the first stage pick-off ring 15. A second-stage drain port is provided at the lower end of the cylinder 17.

  The third-stage steam-water separation unit 5 includes a third-stage inner cylinder 19, a third-stage outer cylinder 20, and a third-stage pick-off ring 21 assembled on the second-stage pick-off ring 18. At the lower end of 18, a third stage drainage port is provided.

  Next, the operation of the gas-liquid mixed flow flowing in the steam-water separator 1 according to this embodiment configured as described above will be described. A gas-liquid mixed flow of steam and cooling water flows from the upper plenum 104 into the stand pipe 2 connected to the shroud head 105 and is installed inside the first stage inner cylinder 7 so as to have the first swirl blade 8 and the second swirl blade 10. And a swirler 12 composed of the hub 9. A centrifugal force is applied to the outer peripheral portion of the gas-liquid mixed flow by the first swirl vane 8, and a centrifugal force greater than that of the first swirl blade 8 is imparted to the central portion by the second swirl blade 10, The flow from the flow path of the blade 8 joins, and the conversion from the droplet in the vapor to the liquid film is promoted in the first stage inner cylinder 7. 80 to 90% or more of the separated liquid film is separated by the first stage pick-off ring 15, and the first stage inner cylinder 7 and the first stage are separated by the pressure difference between the first inner cylinder inner side 7 and the first outer cylinder 14 outer side. It flows down between the outer cylinders 14 and is drained. The vapor and liquid film containing droplets that have passed through the first-stage pick-off ring 15 flow into the second-stage inner cylinder 16, and from the droplets to the liquid film in the same manner as in the first-stage inner cylinder by centrifugal force. The liquid film is separated by the second stage pick-off ring 18. The separated liquid film flows down between the second stage inner cylinder 16 and the second stage outer cylinder 17 due to the pressure difference between the inner side of the second inner cylinder 16 and the outer side of the second outer cylinder 17 and is discharged from the second stage drain port. Then, it flows down along the outer surface of the first stage outer cylinder 14. At this time, the steam flowing out from the second-stage drain outlet together with the drainage rises outside the steam / water separator 1.

  The droplets contained in the steam that passes through the second stage pick-off ring 18 and flows into the third stage inner cylinder 19 adhere to the inner wall of the third stage inner cylinder 19 by centrifugal force, and are separated by the third stage pick-off ring 21. Due to the pressure difference between the inside of the third stage inner cylinder 19 and the outside of the third stage outer cylinder 20, it flows down between the third stage inner cylinder 19 and the third stage outer cylinder and is discharged from the third stage drain port. It flows down along the outer surface of the stepped outer cylinder 17. At this time, the steam that flows out from the third-stage drain outlet together with the drainage rises outside the steam / water separator 1.

  Details of the swirler 12 in the steam separator of the present embodiment are shown in FIG. 1 (b) and FIG. 1 (c). The swirler 12 includes a first swirl vane 8, a second swirl vane 10, a hub 9, and a cylindrical body 11. In FIG. 2B, eight first swirl vanes 8 are provided, but the gist of the present invention is not limited to eight, and may be about six to eight. The second swirl vane 10 has a spiral structure provided in the cylinder 11, and the hub 9 is composed of a streamlined lower end 9a composed of a cone and a hemisphere, a columnar main body 9b, and a cone and a hemisphere. This is composed of a streamlined upper end portion 9c. The 2nd swirl | wing blade 10 is installed in the column-shaped main-body part 9b. The upper end portion 9c of the hub may be cut flat. Further, the cylindrical body 11 can be provided with a notch penetrating from the inner peripheral side of the cylindrical body 11 to the outer peripheral side. If it does in this way, since a gas-liquid mixed stream can be moved to the inside and outside of the cylindrical body 11 through a notch, a higher gas-liquid separation performance can be obtained.

  In the gas-liquid separator according to this embodiment, since the hub 9 is formed in a rod shape, the hub diameter can be reduced to the minimum, and the pressure loss of the gas-liquid separator can be reduced to the maximum. Further, the swirler 12 includes first and second swirl vanes 8 and 10, and the centrifugal force that the second swirl blade 10 imparts to the gas-liquid mixed flow is greater than the centrifugal force that the first swirl vane 8 imparts to the gas-liquid mixed flow. Therefore, the cooling water contained in the central portion of the gas-liquid mixed flow can be efficiently directed toward the inner surface of the first stage inner cylinder 7, and a liquid film is formed on the inner surface of the first stage inner cylinder 7. And can exhibit high air-water separation performance. Moreover, since the steam separator of this example is provided with the cylindrical body 11 on the outer periphery of the second swirl vane 10, it is possible to facilitate the attachment of the first swirl vane 8 to the hub 9 and the second swirl vane 10, The swirler can be easily manufactured. Furthermore, since the steam separator of this example is provided with the swirler 12 on the inner surface of the first stage inner cylinder 7, the pressure loss of the gas-liquid separator can be reduced as compared with the case where the swirler 12 is provided in the diffuser 6. Can do.

  Hereinafter, a second embodiment of a steam separator and a boiling water reactor according to the present invention will be described with reference to FIG. FIG. 2 is an explanatory diagram of a steam separator according to the second embodiment. The boiling water reactor according to the second embodiment is obtained by applying the steam-water separator of FIG. 1 to the improved boiling water reactor shown in FIG.

  As shown in FIGS. 2A, 2B, and 2C, the gas-liquid separator according to the second embodiment includes the second swirl blade 10 having a plurality of blades and omits the cylindrical body 11. The first swirl vane 8 is directly formed at the tip of the second swirl vane 10.

  Since the gas-liquid separator of this example does not have the cylindrical body 11 between the first swirl vane 8 and the second swirl vane 10, the pressure loss of the gas-liquid separator can be reduced as compared with the case of having the cylindrical body 11. While being able to reduce, the movement of the gas-liquid mixed flow from the flow path on the second swirl vane 10 side to the flow path on the first swirl vane 8 side is easy, and gas-liquid separation can be promoted.

  Hereinafter, a third embodiment of the steam-water separator and the boiling water reactor according to the present invention will be described with reference to FIG. FIG. 3 is an explanatory view of a steam separator according to the third embodiment. The boiling water reactor according to the third embodiment is obtained by applying the steam-water separator of FIG. 1 to the improved boiling water reactor shown in FIG.

  As shown in FIG. 3, the gas-liquid separator according to the third embodiment is characterized in that a swirler 12 is provided inside the diffuser 6.

  In the gas-liquid separator of this example, a swirler 12 including a first swirl vane 8, a second swirl vane 10, and a hub 9 is arranged in a high-speed gas-liquid mixed flow that flows in the stand pipe 2 having a small flow path area. Since the turning force is applied, the gas-liquid separation performance in the first stage gas-liquid separation unit 3 can be improved, the weight of the swirler 12 can be reduced, and the earthquake resistance can be improved.

  In addition, in FIG. 3, although the example which equipped the inside of the diffuser 6 with the swirler 12 which concerns on 1st Embodiment shown in FIG. 1 is shown, the summary of this invention is not limited to this, It is of course possible to provide the swirler 12 according to the second embodiment shown in FIG.

  The features and functions of the gas-liquid separator according to the present invention will be described below in comparison with the prior art.

  One of the methods for reducing the acceleration loss, which shows most of the pressure loss of the steam separator, is to reduce the axial velocity by reducing the hub diameter. However, in the method of reducing the hub diameter, since the flow velocity in the axial direction is reduced and the flow velocity in the circumferential direction that affects the gas-liquid separation is also lowered, the gas-liquid separation performance is deteriorated. Further, when the hub diameter is reduced, the exit angle of the swirl vane joined to the hub is reduced, so there is a limit to reducing the pressure loss while securing the design requirement value for gas-liquid separation.

  FIG. 4A schematically shows a cross-sectional view of the prior art first-stage inner cylinder, hub, and swirl vane when viewed from the downstream (above). FIG. 4B schematically shows the relationship between the outer exit angle of the swirl vane joined to the inner cylinder and the inner exit angle joined to the hub at the time of eight swirl vanes.

  In the prior art, although the outer outlet angle is large, the inner outlet angle cannot be increased because the hub diameter is small and the circumferential length is short. When the hub diameter is reduced, the inner exit angle is reduced, so that the rotational speed in the circumferential direction is reduced, and the centrifugal force is not sufficiently applied to the mixed fluid in the central portion of the cylinder in the vicinity of the hub, thereby reducing the gas-liquid separation performance.

  On the other hand, the swirler 12 is comprised by the 1st swirl | wing blade 8, the 2nd swirl | wing blade 10, and the hub 9, and the 2nd swirl | wing blade 10 which enlarged the centrifugal force was ensured, ensuring the flow path of a gas-liquid mixed flow. In the present invention provided inside the swirl vane 8, since the centrifugal force at the center of the cylinder near the hub 9 can be secured, the pressure loss can be further reduced while satisfying the design requirement of gas-liquid separation. .

  Note that the steam-water separator according to the present invention is intended to improve not only the newly installed reactor but also the steam-water separator of the currently operating reactor, thereby improving the power output and economic efficiency of the reactor. It is possible.

It is explanatory drawing of the steam-water separator which concerns on 1st Embodiment. It is explanatory drawing of the steam-water separator which concerns on 2nd Embodiment. It is explanatory drawing of the steam-water separator which concerns on 3rd Embodiment. It is a figure which shows the relationship between the exit angle of the outer side of a turning blade, and the exit angle of an inner side. It is a longitudinal cross-sectional view of an improved boiling water reactor.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Steam separator, 2 ... Stand pipe, 3 ... 1st stage steam / water separation part, 4 ... 2nd stage steam / water separation, 5 ... 3rd stage steam / water separation part, 6 ... Diffuser, 7 ... 1st stage Inner cylinder, 8 ... first swirling blade, 9 ... hub 10 ... second swirling blade, 11 ... cylindrical, 12 ... swirler, 13 ... partition plate, 14 ... first stage outer cylinder, 15 ... first stage pick-off ring, 16 2nd stage inner cylinder, 17 ... 2nd stage outer cylinder, 18 ... 2nd stage pickoff ring, 19 ... 3rd stage inner cylinder, 20 ... 3rd stage outer cylinder, 21 ... 3rd stage pickoff ring, 101 ... Atom Furnace pressure vessel, 102 ... shroud, 103 ... core, 104 ... upper plenum, 105 ... shroud head, 106 ... steam dryer, 107 ... main steam pipe, 108 ... steam dryer skirt, 109 ... feed pipe, 110 ... downcomer, 111 ... Internal pump, 112 ... Lower plenum.

Claims (7)

A plurality of stages of steam / water separation sections are arranged along the flow direction of the gas-liquid mixture flow, and the first stage steam / water separation section disposed at the most upstream side is connected to the upper end of the standpipe via a diffuser. A cylindrical first-stage inner cylinder, which is disposed below the first-stage inner cylinder, applies a centrifugal force to the gas-liquid mixed flow, and the liquid separated from the gas-liquid mixed flow in the first stage A swirler that forms a liquid film on the inner surface of the cylinder, and a first-stage pick-off that is disposed above the first-stage inner cylinder and separates the liquid film formed on the inner surface of the first-stage inner cylinder from the gas-liquid mixed flow For discharging the liquid film separated from the gas-liquid mixed flow by the first stage pick-off ring between the ring and the first stage outer cylinder, which is disposed so as to surround the outside of the first stage inner cylinder. In the air / water separator comprising the first stage outer cylinder constituting the first stage drainage channel of
The swirler is formed in a rod shape, a hub disposed at the center of the first stage inner cylinder, and a first swirl vane that applies centrifugal force to the outer peripheral portion of the gas-liquid mixed flow that flows inside the first stage inner cylinder. And a second swirl vane that applies a centrifugal force to the inner peripheral portion, and the second swirl vane generates a centrifugal force that is greater than the centrifugal force that the first swirl vane imparts to the gas-liquid mixed flow. A gas-liquid separator characterized by giving.   The swirler includes a hub formed in the shape of a rod, a cylindrical body disposed concentrically on the outer periphery of the hub, a first swirl vane formed on an outer surface of the cylindrical body, an outer surface of the hub, and the The gas-liquid separator according to claim 1, comprising a second swirl blade formed between the inner surface of the cylindrical body.   The swirler includes a hub formed in the rod shape, a second swirl blade formed on the outer surface of the hub, and a first swirl blade formed outward from the tip of the second swirl blade. The gas-liquid separator according to claim 1, wherein   The gas-liquid separator according to any one of claims 1 to 3, wherein a tip end of the first swirl vane is joined to an inner surface of the first stage inner cylinder.   The gas-liquid separator according to any one of claims 1 to 3, wherein a tip end of the first swirl vane is joined to an inner surface of the diffuser.   The hub is formed in a streamline shape with a small radius of curvature at the upstream end and a large radius of curvature at the downstream end in the flow direction of the gas-liquid mixed flow. The gas-liquid separator according to claim 5. Reactor pressure vessel filled with cooling water to a predetermined water level, core installed in the shroud, and steam that separates the gas-liquid mixed flow generated by the heat generation of the core into steam containing droplets and cooling water In a boiling water reactor comprising a separator and a steam dryer for removing droplets from steam containing droplets separated by a steam separator,
As the steam / water separator, a plurality of steam / water separators are disposed along the flow direction of the gas / liquid mixed flow, and the first steam / water separator disposed at the most upstream side is provided with a diffuser. A cylindrical first-stage inner cylinder connected to the upper end of the standpipe and a lower part of the first-stage inner cylinder, which is separated from the gas-liquid mixture flow by applying a centrifugal force to the gas-liquid mixture flow A swirler that forms a liquid film on the inner surface of the first stage inner cylinder with liquid, and a liquid film that is disposed above the first stage inner cylinder and that is formed on the inner surface of the first stage inner cylinder. Between the first stage pick-off ring and the first stage outer cylinder, and is separated from the gas-liquid mixed flow by the first stage pick-off ring. A first-stage outer cylinder that constitutes a first-stage drainage channel for discharging the liquid film, and the swirler has a rod shape A hub that is formed and disposed at the center of the first stage inner cylinder, a first swirl vane that applies centrifugal force to the outer peripheral part of the gas-liquid mixed flow that flows inside the first stage inner cylinder, and an inner peripheral part A second swirl vane that applies a centrifugal force, and the second swirl vane includes a component that applies a greater centrifugal force to the gas-liquid mixed flow than the centrifugal force imparted to the gas-liquid mixed flow by the first swirl vane. Boiling water reactor characterized by.

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