WO2017168934A1

WO2017168934A1 - Water intake pit and plant

Info

Publication number: WO2017168934A1
Application number: PCT/JP2017/000627
Authority: WO
Inventors: 貴司川野; 川根　浩; 良三佐々木; 晴治香川
Original assignee: 三菱日立パワーシステムズ株式会社
Priority date: 2016-03-30
Filing date: 2017-01-11
Publication date: 2017-10-05
Also published as: CN108884649A; MY194508A; JP2017179822A; JP6653204B2; CN108884649B

Abstract

A water intake pit comprises: a first plate member (17) that extends from a rear wall to the upstream side direction with respect to water flow when immersed in water, that comprises an upper face (17a) opposite to the bottom end (38A) of an intake port (38), and that defines a first channel (26) between the first plate member and an inner bottom face (11a) of a pit body (11); a second plate member (18) that extends from the rear wall to the upstream side direction when immersed in the water and that is provided above the intake port (38); a second channel (27) provided between the first plate member (17) and the second plate member (18); and a third channel (28) provided above the second plate member (18) and in which water flows.

Description

Intake pit and plant

The present invention relates to a water intake pit and a plant provided with a pit main body and a pump that draws up water flowing in the pit main body.

Conventionally, in a thermal power plant, a desulfurization apparatus is used to purify exhaust gas. Such a desulfurization apparatus purifies exhaust gas by letting water (for example, seawater) fall from above the exhaust gas when purifying the exhaust gas.

The desulfurization device has a water intake pit equipped with a pit body and a pump that draws up water flowing in the pit body. The pump includes a suction pipe and a suction port provided at the lower end of the suction pipe.

The pump is arranged in a water discharge channel for discarding seawater which is cooling water for cooling water supplied to the condenser. The water discharge channel used in the thermal power plant is a water channel having a large size in the depth direction and the width direction.

A part of the suction pipe of the pump and the suction port are immersed in seawater flowing in the water discharge channel in the middle of the water discharge channel. As the water discharge channel, an overflow type water discharge channel is used. When using such a pump, it is important to suppress the generation of air suction vortices from the viewpoint of suppressing a decrease in pump performance.

Patent Document 1 discloses a vortex prevention device for a drainage pump for the purpose of suppressing the generation of air suction vortices around a pump arranged at the end of a pit that is not an overflow type.

JP 2001-214898 A

By the way, conventionally, in a pump arranged in a water discharge channel, a suction port is arranged at a position close to the inner bottom surface of the water discharge channel. For this reason, it was necessary to lengthen the length of the suction pipe.

As described above, when the length of the suction pipe is increased, the cost of the suction pipe is increased and the main shaft of the pump is lengthened. Therefore, it is necessary to separately provide a support member (bearing member), which increases the cost of the intake pit. It was connected.

On the other hand, in Patent Document 1, no consideration is given to the problem of the cost increase of such a water intake pit.

In addition, the distance between the inner bottom surface of the water discharge channel and the lower end of the suction port is conventionally set to a predetermined distance by the plant. Therefore, if the suction port is simply arranged above the inner bottom surface of the water discharge channel than before, the distance between the inner bottom surface of the water discharge channel and the lower end of the suction port becomes larger than before, and there is a risk that countermeasures against vortices may be difficult. Therefore, such a method cannot be used.

Therefore, the present invention can reduce the cost of the intake pit without causing the air suction vortex to be generated and without changing the distance between the bottom surface of the flow path and the lower end of the suction port from the conventional distance. The purpose is to provide a possible intake pit and plant.

The water intake pit according to the first aspect of the present invention extends in a predetermined direction, the pit body in which water flows from the upstream side toward the downstream side, and the width direction of the pit body in the pit body And a pump having a suction pipe immersed in water flowing in an upstream region located on the upstream side of the pit body, and a rear wall provided over the rear wall, and a suction port for sucking the water. In the immersed state, it extends in the direction from the rear wall toward the upstream side, is provided below the suction port, has an upper surface facing the lower end of the suction port, and the pit body A first plate-like member that divides a first flow path between an inner bottom surface and the suction port that extends in a direction from the rear wall toward the upstream side in a state immersed in the water; Provided above, and And a second plate member that divides the second flow channel between the first plate member and the third plate having a third flow channel through which the water flows. The suction pipe is disposed so as to penetrate the second plate member.

Thus, by providing the first plate-like member above the inner bottom surface of the pit body and below the lower end of the suction port, the conventional bottom surface of the pit body and the lower end of the suction port It is possible to shorten the length of the suction pipe immersed in water after matching the distance with the distance between the upper surface of the first plate member and the lower end of the suction port.

And since the length of a suction pipe becomes short, it becomes possible to reduce the cost of a suction pipe, and since it becomes unnecessary to provide the support member (bearing member) which supports a suction pipe separately, the cost of a water intake pit can be reduced. .

Further, the second plate member is provided above the suction port so as to extend in the direction from the rear wall toward the upstream side in the state of being immersed in water, whereby the first plate member and the second plate member are provided. The second flow path partitioned between the plate-shaped member and the third flow path that is disposed on the second plate-shaped member and in which the flowing water comes into contact with air can be completely separated. It becomes possible. Thereby, when an air suction vortex is generated in the third flow path, it is possible to suppress the movement of the air suction vortex to the second flow path by the second plate member. Moreover, since it is possible to suppress the water flowing through the second flow path from coming into contact with air, it is possible to suppress the generation of air suction vortices in the water flowing through the second flow path.

Further, in the water intake pit according to the second aspect of the present invention, the rear wall partitions the inside of the pit body into the upstream region and the downstream region, and a part of the water flowing in the upstream region. The overflow weir may have a height that overflows and flows into the downstream region.

Thus, an overflow dam may be used as the rear wall.

Further, in the intake pit according to the third aspect of the present invention, the overflow dam is provided in a portion of the overflow weir facing the first flow path, and the water flowing through the first flow path is A communication portion that communicates from the upstream region to the downstream region may be included.

As described above, the communication part is provided in the overflow weir, and the water flowing through the third flow path is caused by flowing the water flowing through the first flow path from the upstream side to the downstream side of the overflow weir through the communication part. The difference between the flow rate of water and the flow rate of water flowing through the second flow path can be reduced. Thereby, generation | occurrence | production of the drift resulting from the difference of the flow volume of the water which flows through the 2nd and 3rd flow path can be suppressed. That is, it is possible to suppress a decrease in pump performance due to drift.

In the intake pit according to the fourth aspect of the present invention, the first and second plate-like members may be arranged so as to be parallel to the inner bottom surface of the pit body.

Thus, the first and second plate-like members can be arranged so as to be parallel to the inner bottom surface of the pit body.

Further, in the water intake pit according to the fifth aspect of the present invention, the second plate-like member is disposed so as to be parallel to the inner bottom surface of the pit main body, and the first plate-like member The upper surface of the first plate-shaped member may be inclined with respect to the inner bottom surface of the pit body so that the depth of the second flow path becomes deeper toward the rear wall. Good.

As described above, by arranging the upper surface of the first plate-shaped member to be inclined with respect to the inner bottom surface of the pit main body, the water in the second flow path is aligned with the upper surface of the first plate-shaped member. Therefore, the water flowing in the second flow path can be guided in the direction toward the suction port.

In the water intake pit according to the sixth aspect of the present invention, the width direction of the first to third flow paths is defined on a pair of side surfaces located in the width direction of the first and second plate-like members. Side walls may be provided.

Thus, by providing the side walls that define the width direction of the first to third flow paths, the width of the first to third flow paths can be reduced. Thereby, for example, when the underwater vortex suppressing member capable of suppressing the generation of the underwater vortex is disposed in the second flow path, the generation of the underwater vortex can be effectively suppressed by the underwater vortex suppressing member.

Further, in the intake pit according to the seventh aspect of the present invention, underwater capable of suppressing the generation of underwater vortices in the second flow path around the suction port arranged in the second flow path. A vortex suppression member may be arranged.

As described above, by arranging the underwater vortex suppressing member capable of suppressing the generation of the underwater vortex in the second flow path around the suction port arranged in the second flow path, it is caused by the underwater vortex. A decrease in the performance of the pump can be suppressed.

In the water intake pit according to the eighth aspect of the present invention, a guide for guiding the water flowing through the second flow path to the suction port to the first plate-like member or the second plate-like member. A member may be provided.

By providing the guide member having such a configuration, it is possible to guide water flowing in the second flow path in the direction toward the suction port.

Moreover, the plant according to the ninth aspect of the present invention may include the intake pit.

The plant configured as described above can suppress the generation of air suction vortex, and the cost of the water intake pit can be reduced without changing the distance between the bottom surface of the flow path and the lower end of the suction port from the conventional distance. Can be reduced.

According to the present invention, it is possible to suppress the generation of the air suction vortex, and to reduce the cost of the water intake pit without changing the distance between the bottom surface of the flow path and the lower end of the suction port from the conventional distance. Can do.

It is a top view of the principal part of the intake pit which concerns on the 1st Embodiment of this invention. FIG. ₂ is a cross-sectional view of the intake pit shown in FIG. 1 in the direction of line A ₁ -A ₂ . FIG. 2 is a cross-sectional view of the intake pit shown in FIG. 1 in the direction of line A ₃ -A ₄ . It is sectional drawing which expanded the structure of the suction inlet of the intake pit shown in FIG. 2, and the circumference | surroundings of a suction inlet. It is sectional drawing of the principal part of the water intake pit which concerns on the modification of the 1st Embodiment of this invention. It is a top view of the principal part of the intake pit of the 2nd Embodiment of this invention. FIG. 7 is a cross-sectional view of the intake pit shown in FIG. 6 in the L ₁ -L ₂ line direction. FIG. 8 is a perspective view of the underwater vortex suppressing member shown in FIGS. 6 and 7. It is sectional drawing of the principal part of the intake pit which concerns on the 3rd Embodiment of this invention. It is sectional drawing of the principal part of the intake pit which concerns on the modification of the 3rd Embodiment of this invention. It is sectional drawing of the principal part of the intake pit which concerns on the 4th Embodiment of this invention. It is sectional drawing of the principal part of the intake pit which concerns on the modification of the 4th Embodiment of this invention.

[First Embodiment]
FIG. 1 is a plan view of a main part of a water intake pit according to the first embodiment of the present invention. In FIG. 1, illustration of the pump main body 35 and the suction port 38 shown in FIG. 2 constituting the pump 15 is omitted, and only the suction pipe 37 is shown. In FIG. 1, C is water flowing in the pit body 11 (hereinafter referred to as “water C”), and R1 is a pit body 11 (hereinafter referred to as “upstream”) located upstream from the overflow weir 13 (an example of a rear wall). , R2 indicates a pit body 11 (hereinafter referred to as “downstream region R2”) positioned downstream of the overflow weir 13. The water C includes seawater and the like.

In FIG. 1, B1 is the direction in which the water C flows upstream of the first and second plate-like members 17 and 18 (hereinafter referred to as “B1 direction”), and B2 is the water C in the downstream region R2. The flowing direction (hereinafter referred to as “B2 direction”) and G indicate the flowing direction of water C in the third flow path 28 (hereinafter referred to as “G direction”), respectively. In FIG. 1, the X direction is the extending direction of the pit body 11, the Y direction is the width direction of the pit body 11, and the Z direction is the depth direction of the pit body 11 (the depth direction of water flowing in the pit body 11). Show.

FIG. 2 is a cross-sectional view of the intake pit shown in FIG. 1 in the direction of line A ₁ -A ₂ . In FIG. 2, Ca indicates the upper surface of water C flowing through the third flow path 28 (hereinafter referred to as “upper surface Ca”). 2, the same components as those in the structure shown in FIG.

3 is a cross-sectional view of the intake pit shown in FIG. 1 in the direction of line A ₃ -A ₄ . 3, the same components as those shown in FIGS. 1 and 2 are denoted by the same reference numerals.

FIG. 4 is an enlarged cross-sectional view of the intake port of the intake pit shown in FIG. 2 and the configuration around the intake port. In FIG. 4, D is the diameter (hereinafter referred to as “diameter D”) of the lower end 38 </ b> A of the suction port 38, I is the central axis (hereinafter referred to as “central axis I”) of the suction pipe 37, and J is the lower end of the suction port 38. The distance from 38A to the upper surface 17a of the first plate member 17 (hereinafter referred to as “distance J”), and K the distance from the central axis I to the overflow weir 13 (hereinafter referred to as “distance K”). ing. 4, the same components as those shown in FIGS. 1 to 3 are denoted by the same reference numerals.

With reference to FIGS. 1 to 4, the intake pit 10 of the first embodiment is a facility provided in a plant (for example, a thermal power plant or a chemical plant), and is an example of a pit main body 11 and a rear wall. Overflow weir 13, pump 15, side walls 16-1 to 16-4, first plate member 17, second plate member 18, first flow path 26, and second flow A path 27, a third flow path 28, and a communication portion 31 are included.

The pit body 11 has a bottom plate portion 11A and a pair of

side wall portions

11B and 11C. The bottom plate portion 11 </ b> A extends in the X direction and has an inner bottom surface 11 a of the pit body 11. The pair of

side wall portions

11B and 11C are provided at a pair of ends in the Y direction of the bottom plate portion 11A. Thereby, a pair of

side wall part

11B, 11C is opposingly arranged in the Y direction. The pit body 11 having the above-described configuration extends in the X direction (predetermined direction), and water C flows from the upstream side toward the downstream side.

The overflow weir 13 is provided in the pit body 11 in the Y direction. The lower end of the overflow weir 13 is connected to the inner bottom surface 11a of the bottom plate portion 11A. Of the two ends of the overflow weir 13 located in the Y direction, one end is connected to the side wall portion 11B, and the other end is connected to the side wall portion 11C. As a result, the overflow weir 13 divides the pit body 11 into an upstream region R1 and a downstream region R2 in the X direction.

The height of the overflow weir 13 is such that a part of the water C flowing through the upstream region R1 can overflow and flow into the downstream region R1.

The pump 15 has a pump body 35, a suction pipe 37, and a suction port 38. The pump body 35 has a mechanism (not shown) for pumping water C. The pump body 35 is connected to one end of the suction pipe 37.

The suction pipe 37 extends in the Z direction. A part (lower end side) of the suction pipe 37 is immersed in water C flowing upstream of the overflow weir 13. The other end of the suction pipe 37 is disposed between the first plate member 17 and the second plate member 18. The suction pipe 37 is disposed so as to penetrate the second plate member 18.

When the diameter of the lower end 38A of the suction port 38 is D, the distance K between the central axis I of the suction pipe 37 and the overflow weir 13 can be appropriately set within a range of 0.75D to 1.0D, for example. It is. By setting the distance K within such a range, generation of underwater vortices in the second flow path 27 can be suppressed.

The suction port 38 is provided at the other end of the suction pipe 37. The suction port 38 is disposed between the first plate member 17 and the second plate member 18. The suction port 38 sucks water C flowing through the second flow path 27.

As the suction port 38, for example, a bell mouth can be used. The diameter D of the lower end 38A of the suction port 38 can be appropriately set according to the purpose.

The side walls 16-1 to 16-4 are plate-like members. The side walls 16-1 to 16-4 are predetermined in the order of the side wall 16-1, the side wall 16-2, the side wall 16-3, and the side wall 16-4 in the Y direction in the upstream region R1 in the pit body 11. Are arranged with an interval of. The side walls 16-1 and 16-4 are provided on a pair of side surfaces located in the Y direction (the width direction of the first and second plate members 17 and 18) of the first and

second plate members

17 and 18. It has been. Thus, the side walls 16-1 and 16-4 define the width direction of the first to third flow paths 26 to 28.

The side wall 16-1 faces the side wall portion 11C in a state of being separated from the side wall portion 11C. The side wall 16-4 faces the side wall part 11B in a state of being separated from the side wall part 11B. Thereby, the distance between the side wall 16-1 and the side wall 16-4 in the Y direction is configured to be smaller than the distance between the side wall part 11B and the side wall part 11C.

The side walls 16-1 to 16-4 are orthogonal to the inner bottom surface 11a of the bottom plate portion 11A, and their lower ends are connected to the bottom plate portion 11A. One end of the side walls 16-1 to 16-4 positioned in the X direction is connected to the overflow weir 13. The upper ends of the side walls 16-1 to 16-4 are arranged at a position higher than the upper end of the overflow weir 13. Of the side walls 16-1 to 16-4, two adjacent side walls define the width direction (Y direction) of the first to third flow paths 26 to 28.

Thus, by providing the side walls 16-1 to 16-4 that define the width direction of the first to third channels 26 to 28, the widths of the first to third channels 26 to 28 are narrowed. It becomes possible. Thereby, for example, when the underwater vortex suppressing member that can suppress the generation of the underwater vortex is disposed in the second flow path 27, the generation of the underwater vortex can be effectively suppressed by the underwater vortex suppressing member. .

The first plate member 17 is a rectangular plate member. The first plate-like member 17 is provided in the lower part between the side walls 16-1 to 16-4 while being immersed in water C. Both ends in the Y direction of the first plate-like member 17 are connected to two side walls provided at adjacent positions among the side walls 16-1 to 16-4. One end of the first plate member 17 in the X direction is connected to the lower portion of the overflow weir 13.

The first plate member 17 extends from the overflow weir 13 toward the upstream side. The first plate-like member 17 is disposed so as to be parallel to the inner bottom surface 11a of the bottom plate portion 11A. The first plate-like member 17 defines the depth direction (Z direction) of the first flow path 26 between the inner bottom surface 11a of the bottom plate portion 11A.

The first plate-like member 17 has an upper surface 17a and a lower surface 17b that are flat. The upper surface 17a faces the second plate member 18 with water C interposed therebetween. The lower surface 17b is disposed to face the inner bottom surface 11a of the bottom plate portion 11A with water C interposed therebetween. The upper surface 17 a of the first plate-like member 17 faces the lower end of the suction port 38 and is disposed below the suction port 38. The upper surface 17 a of the first plate member 17 is separated from the suction port 38.

When the diameter of the lower end 38A of the suction port 38 is D, the distance J between the lower end 38A of the suction port 38 and the upper surface 17a can be appropriately set within a range of 0.3D to 0.5D, for example. By setting the distance J within such a range, generation of underwater vortices in the second flow path 27 can be suppressed.

The thickness of the first plate member 17 can be appropriately set within a range of, for example, 500 mm (when the first plate member 17 is a concrete structure). Moreover, as a material of the 1st plate-shaped member 17, the material which has water resistance (when seawater is used as the water C, the material which has seawater resistance) is preferable. As such a material, for example, concrete can be used.

By having the first plate-like member 17 described above, the distance between the inner bottom surface of the conventional pit body and the lower end of the suction port, and the upper surface 17a of the first plate-like member 17 and the lower end 38A of the suction port 38 are obtained. It is possible to shorten the length of the suction pipe 37 immersed in the water C after matching the distance J.

By reducing the length of the suction pipe 37 in this way, the cost of the suction pipe 37 can be reduced, and it is not necessary to separately provide a support member (bearing member) (not shown) that supports the suction pipe 37. The cost of the intake pit 10 can be reduced.

The second plate-shaped member 18 is a rectangular plate-shaped member. The second plate member 18 is provided between the side walls 16-1 to 16-4 positioned above the first plate member 17 in the state of being immersed in water C.

Both ends in the Y direction of the second plate-shaped member 18 are connected to two side walls provided at adjacent positions among the side walls 16-1 to 16-4. One end of the second plate member 18 in the X direction is connected to the upper portion of the overflow weir 13. The second plate-like member 18 extends in the direction from the overflow weir 13 toward the upstream side. The second plate-like member 18 is disposed so as to be parallel to the inner bottom surface 11a of the bottom plate portion 11A.

The second plate-like member 18 has an upper surface 18a and a lower surface 18b that are flat, and a through hole 18A. The upper surface 18 a defines the bottom of the third flow path 28. The lower surface 18 b faces the upper surface 17 a of the first plate-like member 17 with water C interposed therebetween. The through hole 18 </ b> A is a hole for inserting the suction pipe 37. The second plate-like member 18 can be made of, for example, the same thickness and the same material as the first plate-like member 17 described above.

By providing the second plate-shaped member 18 described above, the second flow path 27 partitioned between the first plate-shaped member 17 and the second plate-shaped member 18, and the second plate-shaped member It is possible to completely separate the third flow path 28 that is disposed on 18 and in which the flowing water C is in contact with air.

Thereby, when an air suction vortex is generated in the third flow path 28, the movement of the air suction vortex to the second flow path 27 by the second plate member 18 can be suppressed. In addition, since it is possible to suppress the water C flowing through the second flow path 27 from coming into contact with air, it is possible to suppress the generation of air suction vortices in the water flowing through the second flow path 27.

The arrangement positions of the first and second plate-

like members

17 and 18 in the Z direction can be appropriately set within the range of the height of the overflow weir 13, and are shown in FIGS. The arrangement positions of the first and second plate-

like members

17 and 18 are not limited.

The first flow path 26 is partitioned by the inner bottom surface 11a of the pit body 11 and the first plate member 17 in the depth direction, and the width direction is adjacent to the side walls 16-1 to 16-4. Are divided by two side walls. In the case of FIG.1 and FIG.3, the three 1st flow paths 26 are arranged with respect to the Y direction.

The second flow path 27 is partitioned in the depth direction by the first plate member 17 and the second plate member 18, and the width direction is adjacent to the side walls 16-1 to 16-4. It is divided by two side walls provided in the position. The second flow path 27 is disposed on the first flow path 26 via the first plate member 17. In the case of FIGS. 1 and 3, three second flow paths 27 are arranged in the Y direction.

The bottom of the third flow path 28 is defined by the second plate-shaped member 18, and the width direction is defined by two side walls provided at adjacent positions among the side walls 16-1 to 16-4. ing. The third flow path 28 is disposed on the second flow path 27 via the second plate-like member 18. Water C that flows through the overflow weir 13 flows through the third flow path 28. In the case of FIG.1 and FIG.3, the three 3rd flow paths 28 are arranged with respect to the Y direction. The first to third flow paths 26 to 28 are stacked in the Z direction.

The communication portion 31 is provided so as to penetrate a portion of the overflow weir 13 that faces each first flow path 26. The communication unit 31 allows the water C flowing through the first flow path 26 to communicate from the upstream region R1 to the downstream region R22.

As the shape of the communication part 31 when viewed from the flow direction of the water C, for example, a polygon or a circle can be used. Moreover, the opening area of the communication part 31 is, for example, the flow rate of the water C flowing through the first flow channel 26, the flow rate of the water C flowing through the second flow channel 27, and the water C flowing through the third flow channel 28. It is good to determine so that it may become equal to the flow velocity of.

By having the communication part 31 described above, the third flow path 28 is made to flow by flowing the water C flowing through the first flow path 26 from the upstream side to the downstream side of the overflow weir 13 via the communication part 31. The difference between the flow rate of the flowing water C and the flow rate of the water C flowing through the second flow path 27 can be reduced. Thereby, the generation | occurrence | production of the drift resulting from the difference in the flow volume of the water C which flows through the 2nd and

3rd flow paths

27 and 28 can be suppressed. That is, it is possible to suppress a decrease in performance of the pump 15 due to the drift.

According to the water intake pit 10 of the first embodiment, it is possible to suppress the generation of the air suction vortex in the second flow path 27 in which the suction port 38 is disposed, and the bottom surface of the second flow path 27 The cost of the water intake pit 10 can be reduced without changing the distance J between the upper surface 17a of the first plate-shaped member 17 and the lower end of the suction port 38 from the conventional distance (predetermined distance).

Moreover, the plant (for example, a thermal power plant, a chemical plant, etc.) provided with the intake pit 10 mentioned above can acquire the effect similar to the intake pit 10 of 1st Embodiment.

FIG. 5 is a cross-sectional view of a main part of a water intake pit according to a modification of the first embodiment of the present invention. In FIG. 5, the same components as those in the structure shown in FIG.

Referring to FIG. 5, the intake pit 40 according to the modification of the first embodiment has an inner bottom surface of the pit body 11 such that the depth of the second flow path 27 becomes deeper toward the overflow weir 13. The configuration is the same as that of the water intake pit 10 of the first embodiment except that the upper surface 17a of the first plate member 17 is inclined with respect to 11a.

According to the intake pit 40 of the modified example of the first embodiment, the first plate-like member is arranged by inclining the upper surface 17a of the first plate-like member 17 with respect to the inner bottom surface 11a of the pit body 11. Since the water C flows in the second flow path 27 along the upper surface 17 a of the member 17, the water C flowing in the second flow path 27 can be guided in the direction toward the suction port 38.

[Second Embodiment]
FIG. 6 is a plan view of the main part of the intake pit according to the second embodiment of the present invention. 6, illustration of the pump main body 35 (refer FIG. 7) and the 2nd plate-shaped member 18 (refer FIG. 7) which comprise the pump 15 is abbreviate | omitted for convenience of explanation. Further, in FIG. 6, the suction pipe 37 and the suction port 38 are schematically illustrated so that the positional relationship between the underwater vortex suppressing member 46, the suction pipe 37, and the suction port 38 becomes clear. In FIG. 6, the same components as those in the structure shown in FIG.

FIG. 7 is a cross-sectional view of the intake pit shown in FIG. 6 in the L ₁ -L ₂ line direction. In FIG. 7, the same components as those shown in FIGS. 2 and 6 are denoted by the same reference numerals. FIG. 8 is a perspective view of the underwater vortex suppressing member shown in FIGS. 6 and 7. 8, the same components as those shown in FIGS. 6 and 7 are denoted by the same reference numerals.

With reference to FIGS. 6 to 8, the intake pit 45 of the second embodiment is the same as the intake pit 10 of the first embodiment except that an underwater vortex suppressing member 46 is further provided. It is configured in the same way.

The underwater vortex suppressing member 46 is disposed in the second flow path 27 and around the suction pipe 37. The underwater vortex suppressing member 46 includes a cross-shaped bottom plate portion 49 and first to third column portions 51 to 53.

The cross-shaped bottom plate portion 49 is a member having a cross shape. The cross-shaped bottom plate portion 49 is disposed on the upper surface 17 a of the first plate-like member 17. The cross-shaped bottom plate portion 49 has an outer surface 49 a that contacts the upper surface 17 a of the first plate-like member 17. An intersecting portion located at the center of the cross-shaped bottom plate portion 49 is disposed below the suction port 38. The cross-shaped bottom plate portion 49 configured as described above suppresses the occurrence of underwater vortices on the lower side of the suction port 38.

The first column portion 51 is provided at one end portion disposed on the downstream side of the flow of the water C among the four end portions of the cross-shaped bottom plate portion 49. The first column portion 51 extends in the Z direction and has an outer surface 51 a that faces the surface 13 a of the overflow weir 13. The first column portion 51 having such a configuration suppresses the occurrence of underwater vortices on the downstream side of the suction port 38.

The second column part 52 is provided at one end part arranged in the Y direction among the two end parts of the cross-shaped bottom plate part 49 arranged in the Y direction. The second column part 52 extends in the Z direction.

The third column portion 53 is provided at the other end portion arranged in the Y direction among the two end portions of the cross-shaped bottom plate portion 49 arranged in the Y direction. The third column portion 53 extends in the Z direction. The third column portion 53 is disposed so as to face the second column portion 52 in the Y direction. The height of the third column portion 53 is the same as that of the second column portion 52.

The above-described second and

third column parts

52 and 53 suppress the occurrence of underwater vortices in the Y direction of the suction port 38.

According to the water intake pit 45 of the second embodiment, the underwater vortex suppression capable of suppressing the generation of underwater vortices in the second flow path 27 around the suction port 38 disposed in the second flow path 27. By disposing the member 46, it is possible to suppress a decrease in performance of the pump due to the underwater vortex. Moreover, the intake pit 45 of 2nd Embodiment can acquire the effect similar to the intake pit 10 of 1st Embodiment.

The shape of the underwater vortex suppressing member 46 described above is an example, and the shape of the underwater vortex suppressing member 46 is not limited to the shape shown in FIGS. For example, when a portion where the underwater vortex is likely to be generated is known in advance, the shape may be such that generation of the underwater vortex at that portion is suppressed.

Further, an underwater vortex suppressing member having the same function as the above-described underwater vortex suppressing member 46 may be provided in the intake pit 40 shown in FIG.

(Third embodiment)
FIG. 9 is a cross-sectional view of the main part of a water intake pit according to the third embodiment of the present invention. 9, the same components as those shown in FIGS. 1 to 4 are denoted by the same reference numerals.

Referring to FIG. 9, the water intake pit 60 of the third embodiment shortens the length of the first plate-like member 17, is the first plate-like member located in the X direction and on the upstream side. Except that the guide member 61 is provided at the end of 17, the configuration is the same as the intake pit 10 of the first embodiment.

The guide member 61 is an L-shaped step forming member, has a shallow depth on the inlet side of the second flow path 27, and the second flow path at the position where the first plate-like member 17 is disposed. 27 is a member for increasing the depth of 27. Thereby, a step is formed between the guide member 61 and the first plate-like member 17.

The water C flowing into the second flow path 27 flows along the surface of the guide member 61 that partitions the second flow path 27, and then flows along the upper surface 17 a of the first plate-like member 17. , And supplied to the suction port 38. As a material of the guide member 61, for example, a material similar to that of the first plate member 17 can be used.

According to the water intake pit 60 of the third embodiment, by having the above-described guide member 61 (L-shaped step forming member), the second flow path 27 in the direction toward the suction port 38 (F direction). It is possible to guide the water C flowing in. That is, the water C can be efficiently pumped from the suction port 38 by suppressing the upward flow of the water C in the second flow path 27. Moreover, the intake pit 60 of the third embodiment described above can obtain the same effects as the intake pit 10 of the first embodiment.

In the third embodiment, the case where the first plate member 17 and the guide member 61 are separated from each other has been described as an example. However, the first plate member 17 and the guide member 61 are integrated. It may be.

FIG. 10 is a cross-sectional view of the main part of a water intake pit according to a modification of the third embodiment of the present invention. In FIG. 10, the same components as those of the structure shown in FIG.

Referring to FIG. 10, the intake pit 65 of the modification of the third embodiment is different from the guide member 61 constituting the intake pit 60 of the third embodiment except that a guide member 66 is provided. It is comprised similarly to the intake pit 60 of 3rd Embodiment.
The guide member 66 is provided at the end of the first plate-like member 17 located in the X direction and on the upstream side.

The guide member 66 is a step forming member having a curved shape. The guide member 66 can reduce the depth on the inlet side of the second flow path 27 and increase the depth of the second flow path 27 at the position where the first plate-like member 17 is disposed. It is made into a shape. As a result, the depth of the second flow path 27 gradually increases from the upstream side of the guide member 66 toward the first plate member 17.

The water C flowing into the second flow path 27 flows along the surface of the guide member 66 that partitions the second flow path 27, and then flows along the upper surface 17 a of the first plate-like member 17. , And supplied to the suction port 38. As the material of the guide member 66, for example, the same material as that of the first plate member 17 can be used.

The intake pit 65 of the modification of the third embodiment having the guide member 66 configured as described above can obtain the same effect as the intake pit 60 of the third embodiment described above.

(Fourth embodiment)
FIG. 11 is a cross-sectional view of the main part of a water intake pit according to the fourth embodiment of the present invention. In FIG. 11, the same components as those shown in FIGS. 1 to 4 are denoted by the same reference numerals.

Referring to FIG. 11, the water intake pit 70 of the fourth embodiment is the same as the water intake pit 10 of the first embodiment except that a guide member 71 is provided on the lower surface 18 b of the second plate-like member 18. It is set as the same structure.

The guide member 71 is a member having a quadrangular prism shape extending in the Y direction. The guide member 71 is a member for guiding the moving direction of the water C flowing through the upper part of the second flow path 27 in the direction toward the lower part of the second flow path 27 (the direction toward the suction port 38).

According to the water intake pit 70 of the fourth embodiment, by having the guide member 71 described above, the moving direction of the water C flowing through the upper part of the second flow path 27 is directed toward the lower part of the second flow path 27. Can be guided to. Moreover, the intake pit 70 of the fourth embodiment described above can obtain the same effects as the intake pit 10 of the first embodiment.

In the fourth embodiment, the case where the first plate member 17 and the guide member 71 are separated is described as an example. However, the first plate member 17 and the guide member 71 are integrated. It may be configured.

FIG. 12 is a cross-sectional view of the main part of a water intake pit according to a modification of the fourth embodiment of the present invention. In FIG. 12, the same components as those shown in FIGS. 1 to 4 are denoted by the same reference numerals.

Referring to FIG. 12, the water intake pit 75 of the modified example of the fourth embodiment is different from the guide member 71 constituting the water intake pit 70 of the fourth embodiment except that a guide member 76 is provided. It is comprised similarly to the intake pit 70 of 4th Embodiment.

The guide member 76 has a curved surface 76a disposed on the upstream side. The curved surface 76 a guides the moving direction of the water C flowing through the upper part of the second flow path 27 in the direction toward the lower part of the second flow path 27. As a material of the guide member 76, for example, the same material as that of the second plate member 18 can be used.

The water intake pit 75 of the modified example of the fourth embodiment having such a configuration can reduce the impact of water C hitting the guide member 76 by the curved surface 76a. Moreover, the intake pit 75 of the modification of 4th Embodiment can acquire the effect similar to the intake pit 70 of 4th Embodiment.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Deformation / change is possible.

For example, in the first to fourth embodiments, the overflow weir 13 has been described as an example of the rear wall, but instead of the overflow weir 13, the water C flowing through the third flow path 28 overflows. A rear wall (not shown) that does not flow may be used. In this case, the same effect as in the first to fourth embodiments can be obtained.

Moreover, the guide member 71 shown in FIG. 11 or the guide member 76 shown in FIG. 12 may be provided in the intake pits 60 and 65 shown in FIGS. Thereby, the water C flowing in the second flow path 27 in the direction toward the suction port 38 can be reliably guided.

The present invention is applicable to a water intake pit and a plant including a pit body and a pump that draws up water flowing in the pit body.

10, 40, 45, 60, 65, 70, 75 Intake pit 11 Pit body 11a Inner bottom surface 11A

Bottom plate portion

11B, 11C Side wall portion 13 Overflow weir 13a surface 15 Pump 16-1 to 16-4 Side wall 17

First plate

17a, 18a, Ca

upper surface

17b, 18b lower surface 18 second plate member 18A through hole 26 first channel 27 second channel 28 third channel 31 communication unit 35 pump body 37 suction pipe 38 Suction port 38A Lower end 46 Submersible vortex suppressing member 49 Cross-shaped

bottom plate portion

49a, 51a Outer surface 51 First column portion 52 Second column portion 53

Third column portion

61, 66, 71, 76 Guide member 76a Curved surface B1, B2, E to G directions C Water D Diameter I Central axis J, K Distance R1 Upstream area R2 Downstream area

Claims

A pit body that extends in a predetermined direction and in which water flows from the upstream side toward the downstream side,
In the pit body, a rear wall provided across the width direction of the pit body,
A pump having a suction pipe immersed in water flowing through an upstream region located on the upstream side of the pit body, the suction port including the water suction port;
In the state of being immersed in the water, it extends in the direction from the rear wall toward the upstream side, is provided below the suction port, has an upper surface facing the lower end of the suction port, and A first plate member that divides the first flow path between the inner bottom surface of the pit body;
In the state immersed in the water, it extends in the direction from the rear wall toward the upstream side, and is provided above the suction port. The second plate is provided between the first plate member and the second plate member. A second plate member that partitions the flow path;
With
On the second plate-shaped member, there is a third flow path through which the water flows,
The intake pipe is a water intake pit disposed so as to penetrate the second plate-like member.
The rear wall divides the inside of the pit body into the upstream region and the downstream region, and has a height over which a part of the water flowing through the upstream region overflows and flows into the downstream region. The water intake pit according to claim 1, which is a flow weir.
A communicating portion that is provided in a portion of the overflow weir facing the first flow path and communicates the water flowing through the first flow path from the upstream area to the downstream area; The water intake pit according to claim 2.
The water intake pit according to any one of claims 1 to 3, wherein the first and second plate-like members are arranged so as to be parallel to the inner bottom surface of the pit main body.
The second plate-like member is disposed so as to be parallel to the inner bottom surface of the pit body,
The first plate-like member has an upper surface of the first plate-like member with respect to an inner bottom surface of the pit main body so that the depth of the second flow path becomes deeper toward the rear wall. The water intake pit according to any one of claims 1 to 3, wherein the water intake pit is arranged to be inclined.
The side wall which divides the width direction of the said 1st thru | or 3rd flow path is provided in a pair of side surface located in the width direction of the said 1st and 2nd plate-shaped member, respectively. The intake pit described in item 1.
Any one of Claims 1 thru | or 6 which arrange | position the underwater vortex suppression member which can suppress generation | occurrence | production of the underwater vortex in the said 2nd flow path around the said suction inlet arrange | positioned in the said 2nd flow path. The intake pit according to claim 1.
8. The guide member according to claim 1, wherein a guide member that guides the water flowing through the second flow path to the suction port is provided on the first plate-like member or the second plate-like member. The intake pit described.
A plant including the intake pit according to any one of claims 1 to 8.