JP2000319979A - Multi-stage swirl head - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To make it possible to form a stable swirling flow with a simple structure even at a high head and to suppress the inflow of air. SOLUTION: A spiral chamber 9, a tapered portion 10 formed at a lower end of the spiral chamber 9 so as to temporarily decrease its diameter downward,
A water collecting pipe 13 connected to the spiral chamber 9 from a tangential direction, a straight pipe part 11 connected to a lower part of the tapered part 10, and an upper part having a swirling force eliminating means 18 and a gas separating means 21 formed in the straight pipe part 11. Equipped with a vortex-type head structure 7 and an upper vortex-type head structure 7
A lower spiral chamber 22, a lower tapered portion 23 formed at the lower end of the lower spiral chamber 22 so as to have a diameter gradually reduced downward, and a lower end connected to the lower spiral chamber 22 from a tangential direction and an upper end The lower eddy current head 8 composed of the connecting pipe 25 connected to the lower end of the straight pipe part 11 of the upper eddy current head 7 and the lower straight pipe part 24 connected to the lower part of the lower taper part 23
Provide one or more stages.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-stage swirl type head, and more particularly, it is possible to eliminate falling energy with a simple structure even when water falls at a high head. The present invention relates to a multi-stage vortex-type head structure capable of stabilizing outflow of water from an outlet by suppressing air mixing.

[0002]

2. Description of the Related Art In order to eliminate inundation damage caused by rainwater in urban areas, a part of rainwater that has fallen during heavy rains is temporarily stored in a large storage pipe installed underground, and when the water level of the river falls A flood-prevention facility that pumps water stored in a storage pipe and discharges it to the river is currently being planned.

In the above-mentioned inundation countermeasure facility, a pipe line facility connecting a head extending over several tens of meters between a water collecting pipe for collecting rainwater and a storage pipe provided deep underground is called a head work. As an example of the construction, a vortex-type head construction as shown in FIGS. 6 and 7 has been studied.

FIG. 6 and FIG. 7 show an example of a generally known eddy current type dropping work, in which a water collecting pipe 2 for sending water 1 such as rainwater separated by a diversion facility (not shown) has an upper end. Is provided with a vertical tubular drop shaft 3 connected from the tangential direction, and a horizontally bent outflow pipe 4 is formed at the lower end of the drop shaft 3 to constitute a vortex-type head 5. It is connected to a storage unit such as a storage pipe provided underground not shown.

[0005] In the vortex-type head 5, when water 1 such as rainwater separated by a diversion facility (not shown) is supplied from the tangential direction to the upper end of the drop shaft 3 through the water collecting pipe 2, A swirling flow 6 is formed inside 3,
The falling energy of the water flow is attenuated by the swirling flow 6, and the swirling flow 6 gradually attenuates downward, flows out of the outflow pipe 4, is sent to a storage unit (not shown), and is stored. .

As described above, when the water 1 is swirled and caused to flow down the drop shaft 3, the falling energy of the water 1 can be reduced, and the falling water landing portion at the lower end of the drop shaft 3 is subjected to impact or the like. A large amount of water 1 can flow smoothly to the lower part in a short time without causing vibration or damage.

[0007] In addition to the vortex-type head 5 shown in FIGS. 6 and 7, a spiral plate is provided inside the drop shaft to forcibly form a swirling flow inside the drop shaft. Spiral plate type head works are also considered.

[0008] The spiral plate type head provided with such a spiral plate is forcibly swirling water by the spiral plate and causing the water to flow down. By providing a spiral plate, there is an advantage that the falling energy of water can be effectively eliminated, but on the other hand, the structure is complicated because the spiral plate and the support shaft for supporting it are provided inside the drop shaft. As a result, there is a problem that the production is very difficult and the device becomes very expensive. or,
It is easy to cause a problem that dust contained in rainwater or the like gets caught or adheres to the upper end portion or the mounting corner portion of the spiral plate.

On the other hand, the eddy current head 5 shown in FIGS. 6 and 7 has a simple internal structure and is very easy to manufacture and inexpensive as compared with the spiral plate head. This can be said to be an effective means since the problem that dust is caught or adhered hardly occurs.

[0010]

However, while the eddy current type head 5 shown in FIGS. 6 and 7 has a simple structure, it has a small degree of freedom in terms of head, flow rate, and the like. For example, for the diameter D of the drop shaft, 1
5D to 20D or more (D is 2 meters, 3
In the case of a high head that requires a length of 0 m to 40 m or more), the swirling flow 6 given at the upper part of the vortex-type head 5 is weakened at the lower position and becomes a state close to a vertical flow, For this reason, there is a possibility that the original purpose of the head work of eliminating the falling energy of water may not be achieved.

That is, in order to attenuate the falling energy of the water 1 in the vortex-type head 5, the drop shaft 3
It is necessary to form a stable swirling flow 6 over the entire inside of the nozzle.

In addition, the rate of air entrapment into the outflow pipe 4 in the vortex-type head work 5 is generally large, and in order to cope with the problem that the amount of water stored in the storage section is reduced due to air mixing, the outflow pipe 4 is used. Alternatively, a piping system or the like for air release is installed in the storage unit to remove the mixed air, so that there is a problem that the equipment cost for the air release increases, and the released air is released to the ground. There is a problem that an unpleasant odor may occur in a part.

As described above, in order to apply the swirl type head 5 to a case of a high head, a condition that a stable swirling flow 6 is formed in the entire inside of the drop shaft 3 and the air mixing rate is further reduced is achieved. There is a need.

The present invention has been made in view of the above-mentioned circumstances, and provides a multi-stage vortex-type head with a simple structure capable of forming a stable swirling flow even at a high head and suppressing mixing of air. With the goal.

[0015]

SUMMARY OF THE INVENTION The present invention provides a spiral chamber, a tapered portion formed at the lower end of the spiral chamber so as to have a diameter gradually reduced downward, and a water collecting pipe connected to the spiral chamber from a tangential direction. An upper vortex-type head having a straight pipe portion connected to a lower portion of the tapered portion, and a swirling force eliminating means and a gas separating means formed in the straight pipe part. And a lower tapered portion formed at the lower end of the lower spiral chamber so as to gradually reduce the diameter downward, and a lower end connected to the lower spiral chamber from a tangential direction and an upper end formed at a lower end of a straight pipe portion of the upper spiral type head. The lower eddy current type drop construction consisting of the connected connection pipe and the lower straight pipe section connected to the lower part of the lower taper section is 1
The present invention relates to a multi-stage vortex-type head structure having at least two steps.

In the above means, a swirling force eliminating means may be provided in the lower straight pipe portion of the lower swirl type head drop, and the swirling force eliminating means is provided in the axial direction of the straight pipe part protruding inside the straight pipe part. The projection may be a long projection, the gas separation means may be an orifice, the lower end of the connecting pipe may be connected to the lower spiral chamber via a throttle, and the upper chamber may be connected to the lower spiral chamber. An air outlet may be provided at the center of the shaft.

According to the above means, the following effects can be obtained.

The water introduced from the tangential direction and swirled into the swirl chamber of the upper swirling type drop head is dropped by the swirling force being increased by the tapered portion and flowing down while strongly swirling in the lower straight pipe portion. Energy is effectively attenuated. The water that has flowed down the straight pipe portion is rapidly swept away by the frictional resistance of the swirling force extinguishing means comprising the projection provided on the lower inner surface of the straight pipe portion, whereby the swirling flow is quickly eliminated, whereby the falling energy is effectively attenuated, Further, the pressure loss is increased by the gas separating means using the orifice, so that the air is reliably separated. Therefore, the aeration rate is low,
A stable flow can be formed without causing vibration or damage due to impact or the like on the landing part.

The water from which the falling energy of the water has been reduced by the upper vortex-type head and the water from which the mixed air has been removed is introduced into the lower vortex chamber of the lower vortex-type head via a connecting pipe from the tangential direction. By turning, the turning force is increased by the lower tapered portion and flows down in the lower straight pipe portion, so that the falling energy is reduced. At this time, since the connection pipe is provided with a throttle portion to introduce the water having the increased flow rate into the lower swirl chamber, the swirling force in the lower swirl type head can be increased.
Further, the swirling flow is rapidly eliminated by the frictional resistance of the swirling force extinguishing means comprising the projection provided at the lower part of the lower straight pipe portion of the lower swirl type head, whereby the falling energy is effectively attenuated.

Therefore, according to the above-described multi-stage vortex type head,
By providing the required number of lower vortex-type heads in the lower part of the lower vortex-type head, a swirling flow can be formed well and the fall energy can be attenuated even in the case of an ultra-high head.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 5 show an embodiment of the present invention. FIG. 1 shows a case in which an upper vortex-type head structure 7 and one lower vortex-type head structure 8 are provided. .

In FIG. 1, the upper vortex-type drop head 7 includes a circular spiral chamber 9 having a required diameter, and a tapered portion formed at a lower portion of the spiral chamber 9 so that the diameter is gradually reduced downward. And a straight pipe portion 11 whose upper end is connected to the lower end of the tapered portion 10. The straight pipe portion 11 is provided with the spiral chamber 9.
The diameter is smaller.

Further, as shown in FIG. 2, a water collecting pipe 13 formed from a circular tube into a square tube and having a narrowed portion 12 is connected to the spiral chamber 9 in a tangential direction. Water collecting pipe 13
Is configured to supply water 1 such as rainwater separated by a water separation facility (not shown) to the swirling chamber 9 in a tangential direction by increasing the flow velocity by a throttle unit 12. The spiral chamber 9;
The water collecting pipe 13 connected in the tangential direction and the tapered part 10 constitute the eddy current promoting part 14.

Further, an air outlet 16 for opening the inside of the spiral chamber 9 to the outside is provided at an axial center position of the spiral chamber 9 in the upper plate 15 of the spiral chamber 9. The air outlet 16 may be provided with an air outlet pipe 16 </ b> A that has entered the inside of the spiral chamber 9 as shown by a two-dot chain line.

The inner surface of the lower part of the straight pipe part 11 is shown in FIG.
As shown in FIG. 3, a plurality of projections 17 extending in the axial direction of the straight pipe portion 11 projecting inward to increase the frictional resistance of the swirling flow 6, increase the pressure loss, and eliminate the swirling flow 6. A turning force extinguishing means 18 is provided. The projection 17 can be formed by fixing a narrow plate or bar to the inner surface of the straight pipe portion 11 by welding.

Further, in the lower portion of the turning force eliminating means 18 in the straight pipe portion 11, the gas is reduced by increasing the pressure loss by narrowing the cross-sectional area of the flow passage by an opening 19 having a diameter smaller than the diameter of the straight pipe portion 11. Orifice 20 to be separated
Gas separation means 21 is provided. In FIG. 1, only one orifice 20 is provided, but two or more orifices may be provided.

Further, the turning force eliminating means 1 by the projections 17 is used.
It is also possible to invert the vertical position of the gas separating means 21 by the 8 and the orifice 20 so that the gas separating means 21 is provided on the upper side and the turning force eliminating means 18 is provided on the lower side.

Referring to FIG. 1, a lower vortex-type head 8 includes a cylindrical lower vortex chamber 22 and a lower taper portion 23 formed at a lower portion of the lower vortex chamber 22 so as to have a diameter gradually reduced downward. And a lower straight pipe portion 24 having an upper end connected to a lower end of the lower tapered portion 23. The lower straight pipe part 24 is
The diameter is smaller than that of the lower spiral chamber 22.

Further, as shown in FIG. 5, the lower end of a connection pipe 25 composed of a vent pipe whose upper end is connected to the lower end of the straight pipe part 11 of the upper vortex type drop head 7 is tangential to the lower spiral chamber 22. Connected from the direction.

The connecting pipe 25 forms a throttle section 26 by a vertically elongated square pipe from a circular pipe connected to the lower end of the straight pipe section 11, and the flow rate of water is increased by the throttle section 26 to form a lower spiral chamber. 22 is supplied from the tangential direction. The lower spiral chamber 22, a connecting pipe 25 connected in a tangential direction,
The lower tapered portion 23 forms a lower eddy current promoting portion 27.

The lower inner surface of the lower straight pipe portion 24 of the lower swirl type head 8 is projected inward to increase the frictional resistance of the swirling flow 6, increase the pressure loss, and extinguish the swirling flow 6. A turning force extinguishing means 18 comprising a plurality of projections 17 that are long in the vertical direction is provided. Note that the swirling force eliminating means 18 may not be provided in the lower vortex-type head drop 8.

The outlet pipe 4 as shown in FIG. 6 is connected to the lower end of the lower straight pipe section 24. On the other hand, when it is applied to the case of a higher head, the lower eddy current type head 8 shown in FIG.
A required number of lower vortex heads 8 are connected to the connecting pipe 2
5 for connection.

Next, the operation of the above embodiment will be described.

In FIG. 1, the water 1 sent from the water collecting pipe 13 is squeezed by the throttle unit 12 to increase the flow velocity and is introduced into the swirl chamber 9 from the tangential direction. When turning and further flowing down the tapered portion 10, the turning force is increased, and thus the falling energy flows down the straight pipe portion 11 in a state where it is effectively attenuated.

Further, due to the increase of the swirling force, the air in the water 1 is gathered so as to form an air column A at the center of the tapered portion 10 as shown in FIG. Since the water flows out from the outside 16, the air mixing ratio of the water 1 guided to the straight pipe portion 11 can be significantly reduced.

As shown in FIGS. 1 and 3, the water flowing down while turning inside the straight pipe portion 11 is guided to a turning force eliminating means 18 composed of a projection 17 provided on the inner surface of the straight pipe portion 11.
The swirling flow 6 is rapidly extinguished due to the frictional resistance by 7, thereby effectively damping the falling energy and at the same time increasing the pressure loss.

Further, the water from which the swirling flow 6 has been extinguished by the swirling force extinguishing means 18 is substantially immediately downstream, as shown in FIGS. As a result, the pressure loss is increased, whereby the air mixed in the water 1 is forced to be pushed toward the center of the upper tapered portion 10 where the pressure is low, and the air is reliably separated. You will be

As described above, since the air is effectively separated and removed by the upper vortex head 7, it is possible to reduce the size of the air venting device conventionally provided in the outflow pipe 4 or the storage part. Alternatively, the installation can be omitted altogether.

The water from which the falling energy of the water has been reduced by the upper vortex head 7 and the air from which the air has been removed flows down the connecting pipe 25 from the lower end of the straight pipe section 11 and is throttled by the throttle section 12 to reduce the flow velocity. After being raised, it is tangentially introduced into the lower volute 22 of the lower swirl 8, whereby the water 1 is swirled again in the lower volute 22. The swirling flow 6 formed in the lower spiral chamber 22 has a further increased swirling force when passing through the lower tapered portion 23 and flows down the lower straight pipe portion 24, thereby effectively reducing the falling energy. Attenuated.

The water that has flowed down while turning inside the lower straight pipe portion 24 is guided to the turning force eliminating means 18 composed of a projection 17 provided on the lower inner surface of the lower straight pipe portion 24, and the swirling flow is caused by the frictional resistance of the projection 17. 6 are rapidly extinguished, thereby effectively attenuating the falling energy. As a result, the outflow pipe 4 shown in FIG.
Can be led to.

On the other hand, in the case of a higher head, a required number of lower vortex-type heads 8 can be further provided below the lower vortex-type head 8 in FIG. 1. Even in the case of an ultra-high head, the falling energy can be satisfactorily attenuated and the water can flow down.

It should be noted that the present invention is not limited to the above-described embodiment, but that the swirling force eliminating means and the gas separating means may have shapes other than those shown in the drawings. The connection between the collecting pipe and the connecting pipe may be horizontal or inclined, the shape of the connecting pipe may be variously changed, and other various changes may be made without departing from the scope of the present invention. Of course.

[0044]

According to the present invention, the water introduced from the tangential direction into the swirl chamber of the upper swirl type head structure and swirled by the swirling force is increased by the tapered portion and flows down while strongly swirling in the lower straight pipe portion. This has the effect of effectively attenuating the falling energy. The water that has flowed down the straight pipe portion is rapidly swept away by the frictional resistance of the swirling force extinguishing means formed on the lower inner surface of the straight pipe portion, thereby effectively attenuating the falling energy. There is an effect, and further, there is an effect that the air is reliably separated by increasing the pressure loss by the gas separation means by the orifice. Therefore, there is an effect that a stable flow can be formed with a low air entrapment rate and without causing vibration or damage due to an impact or the like in a drop landing portion.

The water from which the falling energy of the water has been reduced by the upper vortex-type head and the water from which the mixed air has been removed is introduced into the lower vortex chamber of the lower vortex-type head via a connecting pipe from the tangential direction, and again. By turning, the swirling force is further increased by the lower tapered portion to flow down in the lower straight pipe portion, and there is an effect that the falling energy is reduced. At this time, since the connection pipe is provided with a throttle portion to introduce the water whose flow velocity has been increased into the lower swirl chamber, there is an effect that the swirling force in the lower swirl type head can be increased. In addition, the swirling flow is rapidly eliminated by the frictional resistance of the swirling force extinguishing means comprising the projection provided at the lower part of the lower straight pipe portion of the lower vortex type head, so that the drop energy is effectively attenuated. There is.

According to the above-described multi-stage vortex-type head, a required number of lower vortex-type heads are further provided below the lower vortex-type head, so that a swirling flow can be formed well even in the case of an ultra-high head. This has the effect of attenuating the fall energy.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of an embodiment of the present invention.

FIG. 2 is a view taken in the direction of arrows II-II in FIG.

FIG. 3 is a view taken in the direction of arrows III-III in FIG. 1;

FIG. 4 is a view in the direction of arrows IV-IV in FIG. 1;

FIG. 5 is a view in the direction of arrows VV in FIG. 1;

FIG. 6 is a side view showing an example of a conventional swirl type head.

FIG. 7 is a plan view of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water 6 Swirling flow 7 Upper vortex type drop 8 Lower vortex type drop 9 Swirl chamber 10 Taper part 11 Straight pipe part 13 Water collecting pipe 16 Air outlet 16A Air outflow pipe 17 Protrusion 18 Turning force eliminating means 20 Orifice 21 Gas separation Means 22 Lower spiral chamber 23 Lower taper part 24 Lower straight pipe part (straight pipe part) 25 Connection pipe 26 Restricted part

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Satoshi Kawasaki 1 Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Ishikawajima-Harima Heavy Industries Co., Ltd. F-term (reference) 2D063 CA25

Claims (6)

[Claims] 1. A swirl chamber, a tapered portion formed at a lower end of the swirl chamber so as to have a diameter gradually reduced downward, a water collecting pipe connected to the swirl chamber from a tangential direction, and a lower part of the tapered portion. A straight pipe portion, an upper vortex type head having a swirling force eliminating means and a gas separating means formed in the straight pipe part, a lower vortex chamber, a lower vortex chamber, and a lower vortex chamber at the lower end of the lower vortex chamber A lower tapered portion formed so that the diameter is gradually reduced downward, a lower end connected to the lower spiral chamber from a tangential direction, and an upper end connected to a lower end of a straight pipe portion of the upper vortex type drop head; A multi-stage swirl head comprising at least one lower swirl head comprising a lower straight pipe portion connected to a lower part of a tapered portion. 2. The multi-stage vortex-type head drop according to claim 1, further comprising a turning force eliminating means provided in a lower straight pipe portion of the lower vortex-type head drop. 3. The multistage eddy current head according to claim 1, wherein the turning force eliminating means is an axially long projection of the straight pipe protruding inside the straight pipe. 4. The multi-stage vortex-type head drop according to claim 1, wherein the gas separating means is an orifice. 5. The lower part of the connecting pipe is connected to the lower spiral chamber via a throttle part.
Or a multi-stage vortex-type head described in 4. 6. The multi-stage vortex head according to claim 1, wherein an air outlet is provided at the center of the axis of the spiral chamber of the upper vortex head.