JP2002070713A - Air intake system for water mill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air inlet device and an air inlet means which can be manufactured in a low cost and maintained easily. SOLUTION: An air inlet material 19 which is equipped in the flow passage facing to the runner band 10 of a runner 9 or placed in the downstream of the runner 9 and supplying air into flow water rotating the runner 9 is formed in the segment construction inside the inner circumference of the flow passage and a plurality of air inlets 18 to intake air from inlet pipe 5 into the water flow is equipped with air inlet material 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air supply device for increasing the amount of dissolved oxygen in water passing through a water turbine.

[0002]

2. Description of the Related Art In deep water layers such as reservoirs with a water depth of 10 m or less, natural circulation of water is not so much performed, photosynthesis is not as active as the surface layer, and the dissolved oxygen concentration is generally low. If water withdrawn from the lower part of the reservoir passes through the turbine and flows down, the downstream biological environment may be reduced.

[0003] Conventionally, in a dam facility, a method has been adopted in which air is supplied from a land-based compressor to an air diffuser tube installed near the bottom of a reservoir, and air ejected from the air diffuser tube is mixed into a lower layer fluid. Also, an agitation pump is installed near the surface of the water surface to pump low-rise water, and replacement with surface water has been attempted. Alternatively, a method has been practiced in which a stirrer is installed in water and air is supplied into a stirring flow generated by rotation of a stirrer blade to increase the concentration of dissolved oxygen in a reservoir.

[0004] These methods are countermeasures against water in a reservoir upstream of the turbine, and are not necessarily water taken by the turbine. As means for effectively increasing the dissolved oxygen concentration downstream of the water turbine, as shown in FIG. 9, an air passage 12 is provided inside the blade 10 of the rotating runner 9 of the water turbine, and formed into a structure through which air can pass. Air is supplied from the upper cover 4, which is a stationary portion of the water turbine, through the air supply pipe 5, and is supplied to the inside of each blade 10. Attempts have been made to supply air (US Pat. No. 5,879,130).

[0005] In this method, the air supply passage must be formed inside the runner and the blade which is originally not thick in structure, which may increase the number of processing steps of the runner and increase the cost. Also, in this method, there is a concern that the strength of the runner may be reduced.

[0006] The conventional water turbine suction pipe may be provided with an air supply pipe for the purpose of suppressing the vibration of the water turbine caused by the swirling flow generated at the time of partial load operation deviating from the design operation point. When a pressure pulsation is generated by the swirling flow and the water turbine vibrates, air is supplied from the air supply pipe to reduce the pressure pulsation. The purpose of this air supply pipe is different from that of the present invention as described above.

[0007]

In the above-described method of supplying air from the trailing edge of the rotating runner blade of the water turbine, there is a great possibility that the cost will increase due to an increase in the number of processing steps. In addition, it is expected that maintenance is difficult due to the complicated supply passage structure.

The present invention has been made in view of such circumstances, and has as its object to provide a water turbine air supply device that can be manufactured at low cost and that is easy to maintain.

[0009]

In order to achieve the above object, a feature of a water supply device for a water turbine according to the present invention is that the air supply device is provided in a flow path of a running water for rotating a runner and supplies air to the running water. An air supply member to be evacuated is formed in a segment structure on the inner peripheral side of the flow path, and the air supply member is provided with a plurality of through holes for supplying air into flowing water.

Specifically, the present invention provides the following devices.

According to the present invention, there is provided an air supply member provided in a flow path of flowing water for rotating a runner, for supplying air to the flowing water.
In a water supply device for a water turbine having an air supply pipe for supplying the air to the air supply member, the air supply member is formed in a segment structure on an inner peripheral side of the flow path, and supplied from the air supply pipe. A water supply device for a water turbine, comprising: a plurality of through holes for supplying air into the flowing water.

[0012] Preferably, the air supply member is formed on an inner peripheral side of a flow path facing a runner band of the runner.

[0013] Preferably, the air supply member is formed on the inner peripheral side of a flow path located downstream of the runner.

[0014] Preferably, the opening position of each of the through holes on the flowing water surface side is located downstream of the opening position on the air supply tube side.

According to the present invention, there is provided a water turbine having an opening provided on an inner surface of a suction pipe through which water flowing through a guide vane and a runner flows out in a downstream direction, and an air supply pipe for supplying air to the opening. In the air supply device, the opening portion functions as a drain port for draining water leaking from a gap between the guide vanes and water wound up by the runner during an idle operation of the water wheel, and the air supply pipe during operation of the water wheel. The water supply device is configured to function as an air supply port for supplying the air supplied from the water into the flowing water.

Further, the present invention provides an air supply port provided on the inner surface of a suction pipe through which the flowing water that has passed through the runner flows out in a downstream direction, and supplies air to the flowing water, and supplies air to the air supplying port. A water supply device having an air supply pipe, wherein the air supply port is provided in the vicinity of a downstream side of a projection structure provided on an inner surface of the suction pipe and suppressing a swirling flow of the flowing water. Provide a water supply device for a water turbine.

According to the present invention, there is provided a projection structure provided on an inner surface of a suction pipe for allowing flowing water that has passed through a runner to flow in a downstream direction, and suppressing a swirling flow of the flowing water, and supplying air to the projection structure. In the air supply device for a water turbine having an air supply pipe, the protrusion structure has an air supply port for supplying air into the flowing water, and the air supply port is provided according to a direction of a swirling flow of the flowing water. And an air supply device for a water turbine, wherein the air supply direction is changed.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A water supply device for a water turbine according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a water turbine provided with a water supply device for a water turbine according to a first embodiment of the present invention. FIG.
FIG. 3 is a perspective view of an air supply member for the suction pipe of FIG.
FIG. 2 is a plan view of an air supply member for a side pressure chamber in FIG. 1.

As shown in FIG. 1, water taken from a water intake (not shown) of a dam passes through a water pipe (not shown) and enters a casing 1 of a water turbine. After that, it reaches the stay vanes 2, the guide vanes 3, and the runners 9, and the pressure and kinetic energy stored in the water are transmitted to the runners 9. Runner 9
Transmitted through the turbine 7 is converted into electric energy by a generator (not shown) disposed above the main shaft.

The water that has passed through the runner 9 flows out in a water flow direction 17, passes through a suction pipe 16, and reaches downstream.

The present embodiment is an example in which an air supply device including the air supply member 19 shown in FIGS. 2 and 3 is provided in both the suction pipe 16 and the side pressure chamber 14, respectively. An air supply device may be provided only on the suction pipe 16 or only on the suction pipe 16.

The dissolved oxygen concentration detector 30 detects the dissolved oxygen concentration of the water passing through the runner 9, and when the dissolved oxygen concentration is less than a specified value, a signal for opening the air supply valve is sent to a valve control signal generator 29. Sent to. From there, an air supply valve opening operation command is transmitted to the air supply valve 24 and the air supply flow rate control valve 25, and the air in the air source 28 is supplied to the header 22 through the pipe 23.

The supplied air passes through the air supply pipe 5 and enters the air chamber 20, from the air supply port 18 of the air supply member 19 to the side pressure chamber 14.
Out of the flowing water of the pipe or the flowing water of the suction pipe 16. The symbol 19a is attached to the flowing water surface side of the air supply member 19, and the symbol 19b is attached to the counter-current water surface side.

Here, the air supply member 19 for the suction pipe 16 in FIG. 2 will be described.

The air supply member 19 for the suction pipe 16 has a circumferentially divided eight-segment structure in which eight individual air supply members are combined. The air supply port 18 has a plurality of small diameters, and air is sent out into the water from the plurality of openings.

Even if a large amount of air is injected into water at once from a single location, the air does not dissolve in the water, and the effect of increasing the dissolved oxygen concentration in water is poor. Here, air is easily injected into water by injection from a plurality of openings.

Each individual air supply member has a mounting bolt hole 3
1 is fixed to the suction pipe 16 through a bolt. There is an individual air supply member having a butt portion 32, which has been specially considered to facilitate disassembly and assembly. As shown in the figure, the convex individual air supply member shown in FIG. By providing the convex individual air supply member in this manner, an air supply device including the air supply member 19 can be configured without forming a gap in the circumferential direction, and more air can be supplied.

Next, an air supply member 19 for the side pressure chamber 14 shown in FIG.
Will be described.

The air supply member 19 for the side pressure chamber 14 has a circumferentially-divided six-segment structure in which six individual air supply members are combined. The six individual air supply members have the same shape and the same dimensions. As in the case of the suction pipe, there is a mounting bolt hole 31 through which the bolt is fixed to the stationary portion of the side pressure chamber 14.

The air supply member 19 for the suction pipe 16 and the side pressure chamber 14 has a segment structure.
It is economical to replace only the deteriorated part. Economical means that frequent maintenance does not increase the cost and the air supply system can be maintained in the best condition. As a result, the dissolved oxygen concentration increasing method that makes full use of the air supply system can be achieved. Is achieved.

It should be noted that the shape, size, and number of the air supply ports, and the manner of dividing the air supply members are appropriately selected according to the conditions of each hydroelectric power plant.

The replacement of the air supply member 19 on the suction pipe 16 side will be supplemented below.

If it is necessary to replace the air supply member 19, after draining the water turbine, a scaffold is set in the suction pipe 16, the air supply member 19 is disassembled, and the air supply member disassembled from the work manhole. The member 19 is unloaded. Carrying in and mounting may follow the same process. As described above, since the disassembled air supply member 19 can be carried out and carried in from the work manhole, the work can be performed without disassembling other structures.

Returning to FIG. 1, the periphery of the air supply device will be described. The reason that two valves are provided between the air source 28 and the header 22 is that the air supply valve 24 is for a simple full open and full close operation, and the flow control valve 25 enables adjustment according to the situation. That's why. The valve 26 of the air supply pipe system on the side pressure chamber 14 side is
It is for discharging when soil and the like accumulate in the air supply system. The valve 26 of the air supply pipe system on the side of the suction pipe 16 has the same purpose. By the way, the static pressure on the wall surface of the suction pipe 16 of the water turbine may drop below the atmospheric pressure depending on the operating conditions.

In such a case, air supply is naturally performed only by opening the air supply pipe to the atmosphere without forced air supply using the air source 28. The valve 27 is a valve that is opened and closed when the above-described natural air supply state is established. At this time, the valve 26 is open. In the present embodiment, the air chamber 20 on the side of the suction pipe 16 has an inclined structure to prevent accumulation of earth and sand and dust on the bottom.

FIG. 4 is a sectional view of the air supply member 19 shown in FIGS. Air supply port 18 on the flowing water surface side 19a of air supply member 19
Is located at the counter-current water surface side 19b, that is, the air supply source 28.
It is configured to be located downstream from the opening position on the side. With this configuration, intrusion of earth and sand in flowing water into the air supply passage 18a is suppressed, and clogging of the air supply passage 18a is prevented. That is, by improving the soundness of the air supply device including the air supply member 19, a high-performance air supply device can be realized.

FIG. 5 is a sectional view of a water turbine equipped with a water supply device for a water turbine according to a second embodiment of the present invention. FIG.
The same components are denoted by the same symbols. When a standby operation or a phase adjustment operation is requested by a pump turbine or a water turbine, the water surface in the runner 9 room is depressed to perform the idling operation. At this time, water leaks from a gap between the guide vanes 3 that are fully closed, and water that has been wound up by the runners 9 accumulates between the guide vanes 3 and the runners 9. Suction pipe 1
Drain pipe 3 so-called 20DG2 for draining to 6
3 are installed.

A drain pipe 34, commonly called 20DG1, for draining the water in the side pressure chamber 14 is usually provided.

In this embodiment, the drain pipes 33,
34, an air supply pipe 5, an air supply valve 24, and a flow control valve 25 are added. During the idling operation, the air supply valve 2
4. The flow control valve 25 is fully closed and the valves 35 and 36 are fully open. During the operation of the water turbine, the valves 35 and 36 are fully closed, and the air supply valve 24 and the flow control valve 25 are opened.

The air is supplied from the air source 28 through the header 22 and the air supply pipe 5 to the flowing water from the openings 37 and 38 of the suction pipe 16. This air increases the dissolved oxygen concentration in the water.

In this embodiment, the equipment can be operated efficiently and the water can be supplied to the running water of the economical turbine.

FIG. 6 is a sectional view of a water turbine equipped with a water supply device for a water turbine according to a third embodiment of the present invention. FIG.
The same components are denoted by the same symbols.

In the present embodiment, the air supply port 18 is provided downstream of the projection structure 39 for suppressing the swirling flow generated during the partial load operation of the water turbine. Since the location of the air supply port 18 has a lower field pressure than other locations, air can easily enter from the outside. Air supply to a low pressure location and the pressure of the air source 28 can be reduced accordingly. In other words, it is possible to save energy and reduce the facilities of the air source 28.

FIG. 7 is a partial sectional view of a water turbine equipped with a water supply device for a water turbine according to a fourth embodiment of the present invention.
The same components as those in FIG. 6 are denoted by the same symbols.

The present embodiment has been devised by paying attention to the fact that the direction of the swirling flow in the suction pipe 16 changes depending on the operating conditions of the water turbine. Generally, when the water wheel is operated near the design point, the water flowing out of the runner 9 has no swirl component, and the flow in the suction pipe 16 does not become a swirl flow.

At the time of light load operation on the small flow rate side from the design point of the water turbine, the water flowing out of the runner 9 has a swirl component in the same direction as the rotation direction of the runner 9. A swirling flow is generated in the same direction as the rotation direction.

On the other hand, at the time of overload operation on the large flow rate side from the design point of the water turbine, the water flowing out of the runner 9 has a swirl component in the direction opposite to the rotation direction of the runner 9. 9 generates a swirling flow in the opposite direction to the rotation direction.

In FIG. 7, the direction 40a of the swirling flow is the direction of the swirling flow during light load operation, and is the same as the direction of rotation of the runner 9. The direction 40b of the swirling flow is the direction of the swirling flow during the overload operation, and is opposite to the direction of rotation of the runner 9. The above-mentioned swirling flow is generated and the suction pipe 16
When the projection structure 39 collides with the inside, the pressure of the projection structure 39 on the side facing the swirling flow increases, and the pressure on the shadow side thereof decreases. FIG. 8 is a front view of the projection structure 39 having the air supply port 18.

Therefore, when air is supplied into the suction pipe 16, it is more effective to supply air from the negative side of the protruding structure 39 where the pressure becomes low. In the present embodiment, the switching valve 41 is changed according to the operating state, that is, the direction of the swirling flow in the suction pipe 16.
To switch the air supply destination, and to effectively supply air from the air supply port 18 on the low pressure side of the projection structure 39. Thereby, the dissolved oxygen concentration of the water downstream of the turbine can be increased.

The air chamber 20 inside the projection structure 39 shown in the figure is partitioned by a partition 42 into two air chambers. Further, the switching valve 41 has a role of switching air supply to each air chamber and shutting off the air supply.

[0052]

As is apparent from the above description, according to the first, second and third aspects of the present invention, since the air supply member has a segment structure, if the air supply member deteriorates, only the deteriorated portion needs to be replaced. Good and economical advantage, it is easy to maintain the air supply system in the best condition, as a result, it is easy to maintain and improve the dissolved oxygen concentration downstream of the turbine, and to maintain and improve the biological environment downstream of the turbine Can be.

According to the fourth aspect of the present invention, the soundness of the air supply device is improved, and a high-performance air supply device can be realized.

Further, according to the fifth aspect of the present invention, an air supply device that effectively utilizes existing facilities can be realized.

According to the sixth and seventh aspects of the present invention, an energy-saving air supply device can be realized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a water turbine equipped with a water supply device for a water turbine according to a first embodiment of the present invention.

FIG. 2 is a perspective view of an air supply member for the suction pipe of FIG. 1;

FIG. 3 is a plan view of an air supply member for a side pressure chamber in FIG. 1;

FIG. 4 is a sectional view of the air supply member of FIGS. 2 and 3;

FIG. 5 is a sectional view of a water turbine equipped with a water supply device for a water turbine according to a second embodiment of the present invention.

FIG. 6 is a sectional view of a water turbine equipped with a water supply device for a water turbine according to a third embodiment of the present invention.

FIG. 7 is a partial sectional view of a water turbine provided with a water supply device for a water turbine according to a fourth embodiment of the present invention.

FIG. 8 is a front view of the protrusion structure 39 of FIG.

FIG. 9 is a sectional view of a water turbine having an air supply device according to the related art.

[Explanation of symbols]

5 ... air supply pipe, 9 ... runner, 14 ... side pressure chamber, 15 ... runner band, 16 ... suction pipe, 17 ... flowing water direction, 18 ... air supply port, 18a ... air supply passage, 19 ... air supply member, 19a ... air supply Flowing water surface side of air member, 19b ... countercurrent water surface side of air supply member, 20
... air chamber, 22 ... header, 24 ... air supply valve, 25 ... flow control valve, 28 ... air source, 29 ... valve control signal generator, 3
0: dissolved oxygen concentration detector, 33, 34: drain pipe, 39:
Projection structure

Claims (7)

[Claims] An air supply for a water turbine provided in a flow path of running water for rotating a runner, the air supply member supplying air to the flowing water, and an air supply pipe supplying the air to the air supply member. In the device, the air supply member is formed in a segment structure on the inner peripheral side of the flow path, and has a plurality of through holes for supplying air supplied from the air supply pipe into the flowing water. Water turbine air supply system. 2. The water supply device for a water turbine according to claim 1, wherein the air supply member is formed on an inner peripheral side of a flow path facing a runner band of the runner. 3. The air supply device for a water turbine according to claim 1, wherein the air supply member is formed on an inner peripheral side of a flow path located downstream of the runner. 4. The air supply device for a water turbine according to claim 1, wherein an opening position of each of the through holes on a flowing water surface side is located downstream of an opening position on the air supply tube side. . 5. A water supply device for a water turbine, comprising: an opening provided on an inner surface of a suction pipe through which guide water flows through a guide vane and a runner to flow in a downstream direction; and an air supply pipe for supplying air to the opening. The opening functions as a drain port for draining water leaking from the gap between the guide vanes and water wound up by the runner during idle running of the turbine, and is supplied from the air supply pipe during operation of the turbine. A water supply device for a water turbine, which is configured to function as an air supply port for supplying air into the flowing water. 6. An air supply port provided on the inner surface of a suction pipe through which the flowing water passing through the runner flows out in a downstream direction, for supplying air to the flowing water, and an air supply pipe for supplying air to the air supply port. Wherein the air supply port is provided near the downstream side of a projecting structure provided on the inner surface of the suction pipe and suppressing the swirling flow of the flowing water. apparatus. 7. A protruding structure provided on an inner surface of a suction pipe for allowing flowing water passing through a runner to flow out in a downstream direction and suppressing a swirling flow of the flowing water, and an air supply pipe for supplying air to the protruding structure. In the water supply device for a water turbine, the protrusion structure has an air supply port for supplying air into the flowing water, and the air supply port supplies the air in accordance with a direction of a swirling flow of the flowing water. A water supply device for a water turbine, wherein the supply direction is changed.