JP2001003437A - Energy absorbing device for channel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control the flow velocity of a fluid flowing in a channel and restrain the turbulence thereof by mounting an energy absorbing fin comprising a plurality of mutually adjacent fins and a base material for fixing the fins, which are integrally formed, on the inner surface of the channel. SOLUTION: A plurality of mutually adjacent fins 6, 6 and a base material 7 for fixing the fins are integrally formed to constitute an energy absorbing fin 5. The energy absorbing fin 5 is mounted on the inner surface of a channel 2 such as a concrete U-shaped gutter 1 or hollowed steel pipe substantially extending over the whole length of the channel 2 so as to be laid along the flowing direction of a fluid. Only by mounting the energy absorbing fin 5 easy to mold on the channel 2, the contact area of the fluid flowing in the channel 2 with the inner wall of the channel 2 is increased to control the flow velocity of the fluid, and the turbulence of the fluid can be restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water channel damper installed on an inclined surface, and more particularly to a water channel damper for suppressing turbulence in a water channel.

[0002]

2. Description of the Related Art Hitherto, a water channel deenergizing device for suppressing the flow velocity of a fluid has been known. For example, Japanese Patent No. 2506334 discloses a valve in which a butterfly valve is incorporated in a pipe formed by joining hollow steel pipes. A valve energy reducing device has been proposed in which a box is provided and a plurality of projections are provided on the inner peripheral surface of the valve box on the downstream side of the valve box over substantially the entire circumference. In addition,
Japanese Patent Publication No. 7-300893 proposes a gutter flowing water damping material in which, in a concrete U-shaped gutter, a damping material formed in a step shape as a whole is laid at the bottom of the concrete U-shaped gutter.

However, in the valve energy reducing device disclosed in Japanese Patent No. 2506334, it is necessary to provide a butterfly valve and a valve box having a plurality of projections in the piping, so that the structure of the energy reducing device is extremely complicated. However, the cost is high.

In this regard, Japanese Patent Application Laid-Open No. Hei 7-300893 discloses that the step-shaped energy-reducing material separately molded is simply laid at the bottom of the existing concrete U-shaped gutter. Since the energy-reducing material is formed in a step shape, the energy-reducing material is increased in size, and the internal volume in the side groove is significantly reduced. For this reason, it is necessary to use a side groove whose left and right side walls are higher than a normal side groove, and the side groove becomes large and heavy,
Heavy gutters during transport and construction are inconvenient to handle and poor in workability. In addition, the structure in which the energy-reducing material is provided only on the bottom surface of the side groove has a problem that the energy-reducing effect is inferior.

The present invention is intended to solve such a problem, and provides a water channel deenergizing apparatus which is excellent in workability and can effectively suppress turbulent flow which causes water channel damage. The purpose is to do.

[0006]

According to a first aspect of the present invention, there is provided a water channel energy reducing device, wherein a plurality of energy reducing fins are provided adjacent to each other on an inner surface of the water channel, and the energy reducing fins are connected to the flow of the fluid. It is formed over almost the entire length of the water channel along the direction.

According to the above configuration, the contact area between the fluid flowing through the water channel and the inner wall of the water channel is increased by the energy-suppressing fins, and the flow velocity of the fluid is suppressed. Further, the fluid flows along the energy-suppressing fins, and turbulence of the fluid is suppressed by the rectifying action of the energy-suppressing fins.

[0008] The water channel energy dissipating device of claim 2 of the present invention includes:
2. The water channel deenergizing device according to claim 1, wherein the water channel is formed by a U-shaped side groove made of concrete. Thereby, the fluid in the U-shaped side groove is deenergized, and the turbulent flow in the U-shaped side groove installed on the steep slope is suppressed.

According to a third aspect of the present invention, there is provided a water channel de-energizing device according to the first aspect, wherein the water channel is formed of a hollow steel pipe. Thus, when the steel pipe is used as a branch pipe of a pipeline or the like, a pressure difference between the main pipe and a diversion pipe branched and connected to the main pipe is eliminated.

According to a fourth aspect of the present invention, there is provided a water channel energy reducing apparatus according to any one of the first to third aspects, wherein a plurality of fins which are close to each other, and each of the fins is provided. The energy-reducing fin is formed by integrally forming a fixed base member and the energy-reducing fin is attached to the inner surface of the water channel. Thus, the fluid can be deenergized only by attaching the deenergizing fin to the water channel. Further, the flow velocity of the fluid can be adjusted by simply changing the length and interval of the fin.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 4 show a first embodiment of the present invention.
An embodiment is shown, in which 1 is a concrete U-shaped gutter constituting a waterway 2. The side groove 1 has a conventionally well-known structure in which a pair of left and right side walls 1B are erected from both left and right sides of a bottom 1A, and a chamfered inclined surface 4 is formed at an inner corner of the bottom 1A and the side wall 1B.

Numeral 5 is a fin for energy reduction provided inside the side groove 1. A number of parallel fins 6 and a base material 7 for integrating these fins 6 are integrally formed of synthetic resin such as plastic. I have. The base 7 is formed in a U-shape having a pair of left and right side surfaces 5A and a bottom surface 5B so as to fit into the inner surface of the side groove 1, and the inclined surface of the side groove 1 is formed at a portion where the side surface 5A and the bottom surface 5B intersect. 4 are formed along the inclined surface 5C. On the other hand, the fins 6 are formed close to each other along the flow direction of the fluid over the entire length of the base member 7. Then, the base material 7 is fitted into the inner surface of the side groove 1, and the side groove 1 and the above-mentioned energy-reducing fins 5 are integrated by an appropriate means such as bonding. Thereby, the side groove 1
The fins 6 formed on the inner peripheral surface of the bottom groove 1A and the side wall 1B are formed in parallel with each other over the entire length of the side groove 1. Each of the fins 6 rises perpendicularly to the side surface 5A, the bottom surface 5B, and the inclined surface 5C of the base member 7, and the fins 6 formed at the adjacent ends of the surfaces 5A to 5C are slightly spaced from each other. At an angle.

In this embodiment configured as described above, by forming a number of fins 6 parallel to the inner peripheral surface of the side groove 1, the fluid in the side groove 1 can be reduced. That is, the flow velocity of the fluid flowing in the side groove 1 is calculated by the following formula using the Manning formula.

[0014]

(Equation 1) Here, Q = flow rate (m ³ / sec), A = flow area (m ² ), V = flow velocity (m / sec), R = diameter (m),
I = hydrodynamic gradient, n = roughness coefficient. When the width B of the side groove 1 is 1.00 m and the height h of the fluid is 0.5 m, the cross section A of the flowing water is 1.00 × 0.5 = 0.5 m ² . The length S is 3
cm fins 6 at 1 cm intervals S1
The magnification of the margin is 3 + 3 + 1/1 = 7 times, and the margin is (1.00+
2 x 0.50) x 7 = 14 m, and the depth R is 0.05 / 14.0 =
0.03571 m, the flow velocity V of the fluid calculated by the roughness coefficient n of the fin 6 (plastic = 0.012) is 2.021
m / sec.

On the other hand, when the flow velocity V of the concrete gutter without the fins 6 is calculated under the same conditions, the wet side is 1.00 + 2 ×
0.50 = 2 m, the depth R is 0.05 / 2.0 = 0.25 m, and the flow velocity V calculated by the roughness coefficient n of the gutter (concrete = 0.015) is 5.915 m / sec, which is almost 3 of the flow velocity V in this embodiment. Double. That is, by providing a large number of fins 6 parallel to the inner surface of the side groove 1, the flow velocity V of the fluid can be extremely effectively suppressed, and the fluid flows along the fins 6, and the rectification action of the fins 6 The turbulence can be suppressed.

As described above, in this embodiment, since a large number of parallel fins 6 are provided in the side groove 1 close to each other and over the entire length of the side groove 1, the contact area with the fluid is increased. Therefore, the flow velocity of the fluid can be suppressed,
Since the fluid flows along the fins 6, turbulent flow of the fluid can be suppressed, and damage to the water channel 2 can be suppressed.
In general, in a steep gradient of 1/10 to 1/20 in a channel, the flow velocity is high and it is difficult for fish to inhabit the environment. 5, the flow velocity can be suppressed, and the flow velocity can be easily adjusted by changing the length and interval of the fins 6. Therefore, if the gutter 1 is used as a fish movement block such as a dam, it is suitable for fish habitation. Environment can be easily constructed. In addition, fins 5 for energy reduction
Is formed separately from the side groove 1, forming both the side groove 1 and the energy-reducing fins 5 is easy, and if the energy-reducing fins 5 are laid on the existing side groove 1, etc., the side groove 1 can be replaced. , Can be easily deenergized. FIG.
As shown in the figure, in the curved water channel 2, it is necessary to form the outer wall side higher than the inner wall side in the bent portion 1 </ b> R due to centrifugal force. Therefore, it is not necessary to make the outer wall side high.

FIGS. 6 to 8 show a second embodiment of the present invention.
Portions having the same functions as those of the first embodiment are denoted by the same reference numerals, and the description of overlapping portions will be omitted, and only different portions will be described. In this embodiment, the water channel 11 is constituted by the hollow steel pipe 10. Similarly to the first embodiment, the energy-reducing fins 14 integrally formed of a synthetic resin such as plastic having a large number of fins 12 and a base material 13 are attached to the inner peripheral surface of the steel pipe 10. In this embodiment, the steel pipe
Since the energy-suppressing fins 14 are assembled to the inner surface of the base 10, the base material 13 is formed in a hollow cylindrical shape, and the fins 12 formed on the inner surface of the base material 13 are integrally formed on the steel pipe 10 radially toward the inner surface. I have. In the present embodiment, FIG.
As shown in FIG. 1, a steel pipe 10 is used as a branch pipe of a water supply and sewage system or an agricultural pipeline. In such water and sewage or agricultural pipelines, at a position close to the water source, there is a large pressure difference between the main pipe dynamic water level and the required hydraulic water level at the junction between the water distribution pipe 20 and the main pipe 21, and the upstream Although the amount of water greatly exceeding a predetermined flow rate flows through the diversion pipe 20 located on the side of the main pipe and causes water shortage on the downstream side of the main pipe, in the present embodiment,
By forming a large number of fins 6 on the inner surface of the steel pipe 10 which constitutes the flow pipe, the flow force of the fluid flowing through the steel pipe 10 can be reduced, whereby the pressure difference between the main pipe 21 and the diversion pipe line 20 can be reduced. Can be eliminated. That is, the pressure reduction amount of the steel pipe 10 is calculated by the following equation based on the Manning equation described in the first embodiment.

[0018]

(Equation 2) Here, H = amount of reduced pressure (m), R = depth (m), n = roughness coefficient, V = in-pipe speed (m / sec), A = cross-sectional area of flowing water (m ² ), P = water edge ( m), β = magnification of the edge. H = decompression amount (m) is calculated under the condition that the pipe diameter r of the steel pipe 10 is 0.30 m, the length L is 100 m, and the fins 12 are 7.5 cm long and attached to the steel pipe 10 at intervals of 1 cm. The speed V in the pipe is a standard 1.V flowing through a steel pipe 10 having a pipe diameter r of 0.30 m.
20 m / sec, and the roughness coefficient n is set to 0.012 of plastic as in the first embodiment. Therefore, the magnification β of the margin P is 7.5 + 7.5 + 1/1 = 16 times, and the margin P is (π × 0.30) × 16
= 15.0797m, cross section A of flowing water is π × 0.30 ² /4=0.07069
m ² , depth R is 0.07069 / 15.0797 = 0.004688m,
The reduced pressure amount H is 26.428 m.

On the other hand, in the case of the steel pipe 10 without the fins 12,
Is π × 0.30 = 0.94248 m, and the depth R is 0.07069 / 0.9424
8 = 0.075 m, so the roughness coefficient n of the steel pipe 10 (steel pipe = 0.
012) is 0.656 m, and when the steel pipe 10 without the fins 12 is compared with the steel pipe 10 having the fins 12, the reduced pressure H is approximately 40 times. So, for example,
When the steel pipe 10 is used as a branch pipe for water and sewage or an agricultural pipeline, the pressure difference between the main pipe 10A and the water pipe 20 branched and connected thereto is eliminated. Further, similarly to the first embodiment, the amount of reduced pressure can be easily adjusted by changing the length and interval of the fins 12.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments.
Various modifications can be made within the scope of the present invention.
For example, in each of the above embodiments, the side groove or the steel pipe and the energy-suppressing fin are formed of different members, and the base material of the energy-suppressing fin is bonded and fixed to the side groove or the steel pipe. However, the fixing means may be, for example, a screw. The fixing means may be appropriately selected. Further, as shown in FIG. 9, for example, the side groove 1 (steel pipe) and the fin 6 are integrally formed without separating the side groove or the steel pipe and the energy-suppressing fin, or as shown in FIG. Gutter 1
(Steel pipe) may be embedded with only the fins 6. Further, the dimensions, shape, material, length and spacing of the fins and the like of the gutter or the steel pipe are not limited to those in the above-described embodiment, but are shown in FIG.
As shown in FIG. 1, the fin 6A may be formed to be long.

[0021]

According to the first aspect of the present invention, a plurality of energy reducing fins are provided on the inner surface of the water channel, and the energy reducing fins are arranged in the flow direction of the fluid. Since it is formed over substantially the entire length of the water channel along the water channel, the contact area between the fluid flowing through the water channel and the inner wall of the water channel is increased by the energy-suppressing fins. The turbulence of the fluid can be suppressed by the energy reducing fins along the fins.

According to the water channel energy dissipation device of the second aspect of the present invention, in the water channel energy dissipation device of the first aspect, since the water channel is a U-shaped gutter made of concrete, the water channel is installed on a steep slope. The U-shaped side groove can be prevented from being damaged due to turbulence by reducing the fluid in the U-shaped side groove.

According to the water channel de-energizing device of the third aspect of the present invention, in the water channel de-energizing device according to the first aspect, since the water channel is a hollow steel pipe, it is used as a water pipe for a pipeline. In this case, the pressure difference between the main pipe and the water distribution pipe can be eliminated.

According to a fourth aspect of the present invention, there is provided the water channel de-energizing device according to any one of the first to third aspects, wherein the plurality of fins which are close to each other and each of the fins are provided. And the base material for fixing the fin is integrally formed to constitute the energy-reducing fin, and the energy-reducing fin is attached to the inner surface of the water channel. The energy can be reduced, and the energy-saving fin can be easily formed.

[Brief description of the drawings]

FIG. 1 is a front view of a side groove showing a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of the vicinity of the fin.

FIG. 3 is a perspective view of the upper groove.

FIG. 4 is a plan view of the upper groove.

FIG. 5 is a plan view of the bent side groove.

FIG. 6 is a front view of a steel pipe showing a second embodiment of the present invention.

FIG. 7 is a perspective view of the same steel pipe.

FIG. 8 is a schematic explanatory diagram of the same pipeline.

FIG. 9 is an enlarged cross-sectional view showing a modified example of the method for fixing to the energy dissipation fin of the present invention.

FIG. 10 is an enlarged cross-sectional view showing a modified example of the method for fixing the same to another energy-saving fin.

FIG. 11 is a front view of a side groove showing a modification in which the length of the fin is changed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gutter 2,11 Waterway 6,12 Fin 7,13 Base material 5,14 Energy-saving fin 10 Steel pipe

Claims (4)

[Claims] A plurality of energy-suppressing fins are provided on an inner surface of a water channel, and the energy-suppressing fins are formed over substantially the entire length of the water channel along the flow direction of the fluid. Water channel energy dissipating device. 2. The water channel energy dissipation device according to claim 1, wherein said water channel is a U-shaped gutter made of concrete. 3. The water channel energy dissipation device according to claim 1, wherein said water channel is a hollow steel pipe. 4. A plurality of fins adjacent to each other and a base material for fixing the fins are integrally formed to constitute the energy-reducing fin, and the energy-reducing fin is attached to the inner surface of the water channel. 4. The method according to claim 1, wherein
A water channel energy dissipating device according to any one of the preceding claims.