JP2005282081A - Energy absorbing structure and discharge passage used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an energy absorbing structure and a discharge passage used therefor, capable of reducing the site area required for installing a flow passage on the downstream side of an energy absorber, by reducing turbulence and a water surface change of a water flow when bending the downstream flow passage of the energy absorber. <P>SOLUTION: This energy absorbing structure is constituted by using the energy absorber 2, and the discharge passage 3 for outwardly discharging fluid whose energy is absorbed by the energy absorber 2. At this time, a bending part 14 for changing the flow direction of the fluid is formed in the discharge passage 3. A straightening block 13 is arranged on a bottom surface in the bending part 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a derating structure provided with a derating process, and a discharge path used therefor.

  Conventionally, facilities such as a hydroelectric power plant and a sewage facility have been provided with a depressing work in order to depress high-speed water flow (see, for example, Patent Document 1). For example, in a hydroelectric power plant, surplus water is discharged from the spillway to the spillway due to overflow at the time of load interruption, and the discharged water is discharged from the spillway to the river through the drainage channel.

  At this time, the water released by the overflow has a large kinetic energy due to the fall. For this reason, if it is discharged as it is, it may adversely affect the river. Therefore, in order to attenuate the kinetic energy of water, a depressurizer is connected to the end of the spillway.

  As a typical depressurizer used in a hydroelectric power plant, a jump-type depressurizer is known that causes a jump in a water tank provided near the end of a spillway to attenuate kinetic energy (for example, , See Patent Document 1). Specifically, what formed the block and the sub dam in order in the water flow direction in the water tank is known.

In this water jump type depressurization work, the water flowing through the spillway first collides with the block. Thereby, the flow direction of water is dispersed and the kinetic energy is attenuated. Moreover, the kinetic energy of water is further attenuated by the collision with the sub dam. In this way, the water reduced by the reduction work is discharged into the river through the discharge channel.
JP 2003-155770 A

  However, although the water that has been de-energized as described above is guided to the water discharge channel, a bend is formed in the flow path from the de-energizing work to the water discharge channel (hereinafter referred to as “discharge channel”) due to site restrictions. There is a case. In this case, if the angle of bending is small (for example, about 90 degrees), the water reduced by the depressurization work collides with the bent portion, thereby causing a water level difference due to damming and causing drift. For this reason, the flow of water is disturbed downstream of the bent portion, and the fluctuation of the water surface increases, which may adversely affect not only the discharge channel but also the river.

  On the other hand, if the bending is not formed in the discharge channel or the bending angle is increased, the total length of the water discharge channel is increased accordingly. For this reason, the site area required for the installation of the water discharge channel is increased, and the cost for land acquisition is increased. In addition, the construction cost of the canal will increase.

  Further, if the number of blocks constituting the de-energizing work is increased, the de-energizing effect is enhanced. Therefore, even if the bending angle in the discharge path is small, it is considered that the disturbance of the water flow and the fluctuation of the water surface downstream of the bent portion can be reduced. In this case, however, the construction cost of the de-energizing work increases.

  Furthermore, there are cases in which de-energization works are newly installed in existing hydroelectric power stations. In this case, it is considered that the site area is particularly limited. Therefore, it is required to install a spillway, a depressurizer, a discharge channel, and a water discharge channel in a limited site, and to reduce water flow disturbance and water surface fluctuation downstream of the bent portion.

  The purpose of the present invention is to solve the above-mentioned problems and reduce the disturbance of the water flow and the fluctuation of the water surface when the flow path downstream of the depressurizer is bent, and is necessary for installing the flow path downstream of the depressurizer It is an object of the present invention to provide a de-energizing structure capable of reducing the site area and a discharge path used therefor.

  In order to achieve the above object, the reduction structure according to the present invention has a reduction work and a discharge path for discharging the fluid reduced by the reduction work to the outside, It has a bent part formed so that the flow direction of fluid changes, and a rectification block is provided in the bottom in the above-mentioned bent part.

  In order to achieve the above object, the discharge path in the present invention is a discharge path for discharging the fluid depressurized by the depressurization work to the outside, and is bent so as to change the flow direction of the fluid. And a rectifying block is provided on the bottom surface of the bent portion.

  As described above, in the present invention, a rectifying block having a depressurizing effect is provided in the discharge path separately from the depressurizing work. For this reason, it is possible to suppress the occurrence of a water level difference or drift due to damming at the bent portion of the discharge path, and as a result, it is possible to suppress the occurrence of water flow disturbance or water surface fluctuation downstream. Therefore, if the current reducing structure and the discharge path in the present invention are used, the total length of the flow path downstream of the current reducing work can be shortened, and the site area required for installation can be reduced.

  In the de-energizing structure and the discharge path in the present invention, the bent portion is formed so that the flow direction of the fluid changes by approximately 90 degrees, and the rectifying block protrudes from the bottom surface of the bent portion. A first columnar block and a second columnar block, each of the first columnar block and the second columnar block each having a first side facing the fluid before passing through the bent portion, and the first columnar block. A second side surface facing the opposite side of the side surface, a third side surface facing the fluid flow direction after passing through the bent portion, and a fourth side surface facing the opposite side of the third side surface. And the first columnar block has the first side surface when the distance from one side wall surface to the other side wall surface before bending of the discharge path is W. The bend It is in a position advanced by (1 / 5.25) W in the flow direction before bending with respect to the side wall surface on the inner peripheral side after bending of the bent portion, and the third side surface is in front of the bent portion before bending. The second columnar block is arranged such that the first side surface of the second columnar block is located at a position advanced by (1/7) W in the direction opposite to the flow direction after bending with respect to the side wall surface on the inner peripheral side. The first columnar block is located at a position advanced by (1 / 5.25) W in the flow direction before bending with respect to the second side surface of the first columnar block, and the fourth side surface is before bending of the bent portion. It is preferable to adopt an aspect in which the film is disposed so as to be at a position advanced by (1/7) W in the flow direction after being bent with respect to the outer peripheral side wall surface.

  Further, in the depressurizing structure and the discharge path in the present invention, the first columnar block and the second columnar block are formed in a regular quadrangular prism shape, and the length of one side in the cross section of the regular quadrangular column is ( It is also preferable that the aspect is set to 1 / 3.5) W.

  Furthermore, when the fluid depth when the fluid is allowed to flow into the bent portion without forming the first columnar block and the second columnar block is h, the first columnar block and the It is also preferable that the height of the second columnar block is set to (1 / 1.51) h.

  In the energy reducing structure in the present invention, the energy reducing work is a jump water type energy reducing work, and has a water tank, a block, and a sub dam. It can be set as the aspect currently installed in the bottom face of the said water tank in order along a flow direction. Further, the spillway for guiding the water discharged from the spillway is connected to the depressurizer, and the discharge path is connected to the spillway for guiding the water discharged from the spillway to the river It can also be.

  Hereinafter, the de-energizing structure and the discharge path in the embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view showing an example of a derating structure in the embodiment of the present invention.

  As shown in FIG. 1, the force-reducing structure 10 includes a pressure-reducing work 2 and a discharge path 3 that discharges the fluid relieved by the pressure-reducing work 2 to the outside. In FIG. 1, the arrows indicate the direction of fluid flow. In the example of FIG. 1, the energy reducing work 2 is connected to the spillway 1. For this reason, the water (fluid) released from the spillway due to overflow is guided to the depressurizer 2 by the spillway 1 and is deenergized by the depressurizer 2. The water reduced by the depressurizer 2 flows into the discharge path 3. Reference numeral 5 denotes a power plant.

  As shown in FIG. 1, the discharge path 3 is provided with a bent portion 14. For this reason, the flow direction of the water flowing through the discharge path 3 is changed by the bent portion 14. In the example of FIG. 1, the end of the discharge path 3 is connected to the water discharge path 4. Therefore, the water flowing through the discharge channel 3 is discharged into the river through the water discharge channel 4 after the flow direction is changed. Further, the de-energizing structure 10, the spillway 1, and the water discharge path 4 are made of concrete.

  Here, the concrete structure of the depressurization work 2 and the discharge path 3 is demonstrated using FIGS. 2A and 2B are schematic configuration diagrams showing an example of a reduction structure and a discharge path according to the embodiment of the present invention. FIG. 2A is a plan view and FIG. 2B is a cross-sectional view. FIG. 3 is an enlarged perspective view showing an example of the energy reducing work used in the energy reducing structure in the embodiment of the present invention. FIG. 4 is an enlarged perspective view showing an example of the discharge path in the embodiment of the present invention.

  First, the configuration of the energy reducing work 2 in the present embodiment will be described. As shown in FIG.2 and FIG.3, in this Embodiment, the energy reducing work 2 which comprises a power reducing structure is a jumping type energy reducing work. The energy reducing work 2 includes a water tank 9, a first block group 6, a second block group 7, and a sub dam 8. The inlet side of the water tank 9 is connected to the spillway 1, and the outlet side is connected to the discharge path 3. The first block group 6 in the first row, the second block group 7 in the second row, and the sub dam 8 are installed on the bottom surface of the water tank 9 in order along the water flow direction.

  2 and FIG. 3, first, water introduced from the spillway flows along the slope 15 and collides with the first block group 6 and the second block group 7 one after another. . At each collision, the water flow direction is dispersed and the water loses kinetic energy. Next, the water colliding with the first block group 6 and the second block group 7 further collides with the sub dam 8 to cause a water jump phenomenon. As a result, the water further loses kinetic energy, and the flow rate of the water is greatly reduced as compared with the case where it flows into the depressurizer 2.

  2 and 3, the block group provided upstream of the sub dam 8 has two rows, but the number of blocks in the block group is not particularly limited. Further, the number of blocks constituting each of the first block group 6 and the second block group 7 is not particularly limited. In the present invention, the number of blocks in the block group and the number of blocks constituting the block group can be appropriately set according to the scale, cost, etc. of the hydroelectric power plant.

  In the example of FIGS. 2 and 3, the slope 15 is formed so that the cross-sectional shape thereof coincides with the free fall curve of water discharged from the spillway 1, but in the present invention, the shape of the slope is It is not particularly limited. The inclined surface 15 may be an inclined plane. However, the flow velocity of the water flowing on the slope 15 is high, and if a space is generated between the flowing water and the slope 15, a negative pressure is generated and the concrete forming the slope 15 is damaged. For this reason, it is preferable to form the slope 15 so that it may correspond with the free fall curve of water, as shown in FIG.2 and FIG.3.

  In the present invention, the energy reducing work 2 is not limited to the jumping type. In the present invention, the stress reducing work 2 may be a vertical pile type power reducing work, an impact type power reducing work or the like.

  Next, the structure of the discharge path 3 in this Embodiment is demonstrated. As shown in FIGS. 2 and 4, a bent portion 14 is provided near the end of the discharge path 3. For this reason, as described above, the water depressurized by the depressurization work 2 flows into the water discharge channel 4 (see FIG. 1) after the flow direction is changed. Moreover, in this Embodiment, as FIG.2 and FIG.4 shows, the bending part 14 is formed so that the flow direction of water may change about 90 degree | times. Therefore, as described in the background art, the bent angle of the flow path by the bent portion 14 is small, and the water flow is turbulent and the water level is likely to change in the water discharge channel 4 (see FIG. 1).

  However, in the present embodiment, as shown in FIGS. 2 and 4, the bent portion 14 is provided with a rectifying block 13. In the example of FIGS. 2 and 4, the rectifying block 13 is formed of a first columnar block 11 and a second columnar block 12.

  As shown in FIG. 4, the first columnar block 11 includes a first side surface 11 a facing the water before passing through the bent portion 14, and a second side surface facing the opposite side of the first side surface 11. 11b, a third side surface 11c facing the water flow direction after passing through the bent portion 14, and a fourth side surface 11d facing the opposite side of the third side surface. In addition, the 1st columnar block 11 is formed in the regular square column shape, and the area in each of the 1st side surface 11a-the 4th side surface 11d is the same.

  Further, the second columnar block 12 is also formed in the shape of a regular quadrangular column like the first columnar block 11, and the first side surface 12a, the second side surface 12b, the third side surface 12c, and the fourth side block 12 are formed. It has a side surface 12d. Further, the first side surface 12a to the fourth side surface 12d of the second columnar block 12 are directed to the first side surface 11a to the fourth side surface 11d of the first columnar block 11, respectively. The direction is the same.

  With such a configuration, the rectification block 13 functions to reduce the momentum of the flow from the depressurizer 2 and has the effect of dispersing the momentum of the water flow in the width direction of the water channel after being bent. Therefore, by installing the rectifying block 13, it is possible to suppress the occurrence of damming up and drifting of the water surface when the water from the depressurizer 2 collides with the bent portion 14. As a result, water flow disturbance and water surface fluctuations are reduced.

  From this, if the de-energizing structure 10 and the discharge path 3 are employed, the flow of water from the turbulent portion 2 to the river can be bent because the disturbance of the water flow and the water surface fluctuation in the bent portion 14 can be reduced. Therefore, the water discharge channel (see FIG. 1) can be installed within the limited site at the shortest distance, and the cost for construction of the hydroelectric power plant can be reduced. Moreover, if it is the reduction | decrease structure 10 and the discharge path 3, introduction to the existing hydroelectric power station is also easy.

  2 and 4, the bent portion 14 is formed so that the water flow direction changes by 90 degrees. However, in the present invention, the angle of the water flow direction changed by the bent portion 14 is particularly limited. Is not to be done. The present invention can be applied without particular limitation as long as the bent portion 14 causes a disturbance in the flow of water and fluctuations in the water surface, which may adversely affect the river. In such a case, the angle in the water flow direction that varies depending on the bent portion 14 may be, for example, a range of 90 degrees or more and less than 180 degrees.

  In the present invention, the shape of the rectifying block 13 is not particularly limited. Further, in the example of FIGS. 2 and 4, in the bent portion 14, corners are formed at the boundary between the side wall of the discharge path 3 before bending and the side wall of the discharge path 3 after bending. It is not limited to the embodiment. In the present invention, an aspect in which the side wall of the discharge path 3 before bending and the side wall of the discharge path 3 after bending are connected by a curved surface, or an aspect in which the boundary is chamfered may be used.

  Moreover, in the example of FIG. 2, the discharge path 3 is bent to such an extent that no drift occurs at the two locations 16a and 16b upstream of the bent portion 14 due to site restrictions. It is not limited. In the present invention, the discharge path 3 may be a flow path that is not bent except for the bent portion 14.

  In this specification, the “discharge path before bending” refers to a discharge path through which water (fluid) before passing through the bent portion 14 flows, and the “discharge path after bending” refers to the bent portion 14. It refers to the discharge path through which water (fluid) passes.

  Next, a preferred position and size of the rectifying block 13 shown in FIGS. 2 and 4 will be described with reference to FIG. FIGS. 5A and 5B are diagrams showing the rectifying block 13 provided in the discharge path 3 shown in FIGS. 2 and 4. FIG. 5A is a plan view and FIG. 5B is a cross-sectional view.

  In the example of FIGS. 2 and 4, as shown in FIG. 5A, the position and the cross-sectional size of the first columnar block 11 and the second columnar block 12 are the same as those before the discharge passage 3 is bent. It is determined using the distance W from the peripheral side wall surface 3a to the peripheral side wall surface 3b. Specifically, the length M of one side in the cross section of the regular quadrangular column is preferably set to (1 / 3.5) W.

  In FIG. 5, the side wall surface 3 c indicates the side wall surface on the inner peripheral side after the bent portion 14 is bent. Further, the side wall surface 3d indicates the side wall surface on the outer peripheral side after the bent portion 14 is bent.

  The position of the first columnar block 11 is set using the distance W on the basis of the inner peripheral side wall surface 3c after bending and the inner peripheral side wall surface 3a before bending. The position of the second columnar block 12 is set using the distance W on the basis of the second side surface 11b of the first columnar block 11 and the side wall surface 3b on the outer peripheral side before bending.

  Specifically, the first columnar block 11 has the first side surface 11a at a position where the first side surface 11a is bent with respect to the side wall surface 3c and advanced by a distance LH1 in the flow direction before the first side block 11c. It arrange | positions so that it may exist in the position which advanced the distance LV1 in the direction opposite to the flow direction after bending on the wall surface 3a. At this time, LH1 is preferably set to (1 / 5.25) W. LV1 is preferably set to (1/7) W.

  Further, the second columnar block 12 has a first side surface 12a at a position advanced by a distance LH2 in the flow direction before bending with respect to the second side surface 11b of the first columnar block 11, and its fourth side. The side surface 12d is bent with respect to the side wall surface 3b as a reference so as to be in a position advanced by LV3 in the flow direction after. At this time, LH2 is preferably set to (1 / 5.25) W. LV3 is preferably set to (1/7) W.

  In the second columnar block 12, the arrangement can be performed based on the fourth side surface 11d of the first columnar block 11 instead of the side wall surface 3b. In this case, the first side surface 12a is positioned in the same manner as described above, and the third side surface 12c is in the direction opposite to the flow direction after bending with respect to the fourth side surface 11d of the first columnar block 11. It is arrange | positioned so that it may exist in the position advanced LV2. At this time, LV2 is preferably set to (1/7) W.

  In the example of FIGS. 2 and 4, as shown in FIG. 5B, the height T of the first columnar block 11 and the second columnar block 12 is determined using the water depth h. . The water depth h is the water depth when water is caused to flow into the bent portion 14 without forming the first columnar block 11 and the second columnar block 12. At this time, the height T of the first columnar block 11 and the second columnar block 12 is preferably set to (1 / 1.51) h.

  By the way, if the water flow momentum is simply reduced, the first columnar block 11 and the second columnar block 12 may be enlarged. However, if it is too large, the water surface at the bent portion 14 becomes too high, and the water surface difference from the downstream becomes large, which may make it difficult to disturb the water flow and reduce the water level fluctuation. Therefore, it is preferable to set the size of the first columnar block 11 and the second columnar block 12 as described above. In this case, the flow of water can be effectively flowed with the minimum necessary lift. Distribute momentum.

  As described above, in the present embodiment, an example in which the de-energizing structure and the discharge path of the present invention are applied to the spillway of a hydroelectric power plant is described. However, the present invention is not limited to this. The de-energizing structure and the discharge path of the present invention can be applied to any equipment other than a hydroelectric power plant, for example, equipment that requires the de-energization of fluid flowing at high speed, such as sewage equipment.

  As described above, according to the present invention, it is possible to bend the flow path while suppressing the occurrence of turbulence of the water flow and the fluctuation of the water surface downstream of the depressurizer that deviates the fluid flowing at high speed. . For this reason, since the freedom degree of the design of the flow path in the downstream of a depressurization work can be improved, the required site can be reduced and the flow path length can be shortened. As a result, it is possible to reduce costs in facilities that require a depressurization work, such as hydroelectric power plants and sewage facilities.

It is a top view which shows an example of the suppression structure in embodiment of this invention. It is a schematic block diagram which shows an example of the decelerating structure and discharge path in embodiment of this invention, Fig.2 (a) is a top view, FIG.2 (b) is shown with sectional drawing. It is a perspective view which expands and shows an example of the energy-reduction work used for the energy-reduction structure in embodiment of this invention. It is a perspective view which expands and shows an example of the discharge path in embodiment of this invention. It is a figure which shows the rectification | straightening block 13 provided in the discharge path 3 shown in FIG.2 and FIG.4, Fig.5 (a) is a top view, FIG.5 (b) is shown with sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Spillway 2 Reduction | restoration work 3 Drainage path 3a-3d Side wall surface 4 Drainage channel 5 Power plant 6 1st block group 7 2nd block group 8 Subdam 9 Water tank 10 Derating structure 11 1st columnar block 11a 1st 1 side surface 11b second side surface 11c third side surface 11d fourth side surface 12 second columnar block 12a first side surface 12b second side surface 12c third side surface 12d fourth side surface 13 rectifying block 14 bent portion 15 Slope 16a, 16b Bending point

Claims (10)

A depressurization work, and a discharge path for discharging the fluid depressurized by the depressurization work to the outside,
The said discharge path has the bending part formed so that the flow direction of the said fluid might change, and the rectification | straightening structure by which the rectification | straightening block is provided in the bottom face in the said bending part. The bent portion is formed such that the flow direction of the fluid changes by approximately 90 degrees;
The rectifying block is formed of a first columnar block and a second columnar block protruding from the bottom surface in the bent portion,
Each of the first columnar block and the second columnar block includes a first side surface facing the fluid before passing through the bent portion, and a second side surface facing the opposite side of the first side surface. And at least a third side surface facing the flow direction of the fluid after passing through the bent portion, and a fourth side surface facing the opposite side of the third side surface,
When the distance from one side wall surface to the other side wall surface before bending of the discharge path is W,
The first columnar block has a position where the first side surface advances (1 / 5.25) W in the flow direction before bending with respect to the side wall surface on the inner peripheral side after the bending portion is bent. And the third side surface is disposed at a position advanced by (1/7) W in a direction opposite to the flow direction after bending with respect to the inner peripheral side wall surface before bending of the bent portion. And
In the second columnar block, the first side surface of the second columnar block is located at a position advanced by (1 / 5.25) W in the flow direction before bending with respect to the second side surface of the first columnar block. The fourth side surface is arranged so as to be located at a position advanced by (1/7) W in the flow direction after bending with respect to the side wall surface on the outer peripheral side before bending of the bent portion. Derating structure as described.   The first columnar block and the second columnar block are formed in a regular quadrangular prism shape, and the length of one side in the cross section of the regular quadrangular column is set to (1 / 3.5) W. Derating structure as described.   When the fluid depth of the fluid when the fluid is allowed to flow into the bent portion without forming the first columnar block and the second columnar block is h, the first columnar block and the second columnar block are formed. The de-energizing structure according to claim 2 or 3, wherein a height of the columnar block is set to (1 / 1.51) h. The depressurizer is a jump type depressurizer, and has a water tank, a block, and a sub dam.
The said block and the said auxiliary | assistant dam are the suppression structures in any one of Claims 1-4 installed in the bottom face of the said water tank in order along the flow direction of the said fluid. A spillway that guides water released from the spillway is connected to the depressurizer,
The de-energizing structure according to any one of claims 1 to 5, wherein the discharge channel is connected to a water discharge channel that guides water discharged from the spillway to a river. A discharge path for discharging the fluid reduced by the depressurizer to the outside,
A bent portion formed to change the flow direction of the fluid;
A discharge path, wherein a rectifying block is provided on a bottom surface of the bent portion. The bent portion is formed such that the flow direction of the fluid changes by approximately 90 degrees;
The rectifying block is formed of a first columnar block and a second columnar block protruding from the bottom surface in the bent portion,
Each of the first columnar block and the second columnar block includes a first side surface facing the fluid before passing through the bent portion, and a second side surface facing the opposite side of the first side surface, , Having at least a third side faced in the fluid flow direction after passing through the bent portion and a fourth side face facing away from the third side face,
When the distance from one side wall surface to the other side wall surface before bending of the discharge path is W,
The first columnar block has a position where the first side surface advances (1 / 5.25) W in the flow direction before bending with respect to the side wall surface on the inner peripheral side after the bending portion is bent. And the third side surface is disposed at a position advanced by (1/7) W in a direction opposite to the flow direction after the bending with respect to the side wall surface on the inner peripheral side before the bending portion is bent. And
In the second columnar block, the first side surface is in a position advanced by (1 / 5.25) W in the flow direction before bending with respect to the second side surface of the first columnar block. The fourth side surface is arranged so as to be in a position advanced by (1/7) W in the flow direction after bending with respect to the side wall surface on the outer peripheral side before bending of the bent portion. The described discharge path.   The first columnar block and the second columnar block are formed in a regular quadrangular prism shape, and a length of one side in a cross section of the regular quadrangular column is set to (1 / 3.5) W. The described discharge path.   When the fluid depth of the fluid when the fluid is allowed to flow into the bent portion without forming the first columnar block and the second columnar block is h, the first columnar block and the second columnar block are formed. The discharge path according to claim 8 or 9, wherein the height of the columnar block is set to (1 / 1.51) h.

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