CN105821819B - It is a kind of to improve the vent device of tailwater tunnel pressure - Google Patents
It is a kind of to improve the vent device of tailwater tunnel pressure Download PDFInfo
- Publication number
- CN105821819B CN105821819B CN201610218295.9A CN201610218295A CN105821819B CN 105821819 B CN105821819 B CN 105821819B CN 201610218295 A CN201610218295 A CN 201610218295A CN 105821819 B CN105821819 B CN 105821819B
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- tunnel
- ventilating opening
- air
- tailwater tunnel
- pressure
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02B—HYDRAULIC ENGINEERING
- E02B9/00—Water-power plants; Layout, construction or equipment, methods of, or apparatus for, making same
- E02B9/02—Water-ways
- E02B9/06—Pressure galleries or pressure conduits; Galleries specially adapted to house pressure conduits; Means specially adapted for use therewith, e.g. housings, valves, gates
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/20—Hydro energy
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Lining And Supports For Tunnels (AREA)
- Revetment (AREA)
Abstract
Improve the vent device of tailwater tunnel pressure the invention discloses a kind of, be made up of panel, two-way air port, unidirectional ventilating opening, choke lid, spring, column, bearing, rubber blanket etc..When air flows into tunnel by outside by passage, unidirectional ventilating opening is fully open, and hole area of now ventilating is in maximum, can effectively alleviate the negative pressure in tunnel；When air by tunnel by passage flow to it is outside constantly, unidirectional ventilating opening Close All, now passage only have two-way air port to be vented, the shock pressure at the end of exhaust can be effectively reduced, it is ensured that the safe operation of tunnel.The present invention is being met on the premise of other adjust guaranteed requests, shock pressure when negative pressure when can alleviate air inlet significantly in tunnel and exhaust, and especially for the higher tailwater tunnel of floor elevation, effect is more notable.
Description
Technical field
It is more particularly to a kind of to be used to improve tail tunnel of hydropower station pressure the present invention relates to Hydraulic and Hydro-Power Engineering technical field
The vent device of power, it is adaptable to the tail tunnel of hydropower station with passage.
Background technology
Large-scale run-of-river power station early construction needs the huge Construction diversion tunnel of construction scale, and designing will construct often
Diversion tunnel is combined with hydropower station tail water system, and the engineering later stage transforms part diversion tunnel into generating tailwater tunnel.Work as downstream stage
Reservoir level close to hole push up when, the initial pressure in tailwater tunnel is smaller, when transient process occurs for power station, the pressure in tail water road
And surge change relatively acutely, low pressure is produced in the tailwater tunnel that may result in position higher position, if low pressure reaches vaporization
I.e. there may be column separation phenomenon in pressure, hole, further result in fluid column and make up to cause huge pressure, will seriously endanger
And the safety of building.In order to avoid occurring such accident in design, passage 2 is often set at the top high point of tailwater tunnel 1,
As shown in Figure 1.Slow down the reduction of pressure in tailwater tunnel by way of tonifying Qi, now passage is in the shape of intake and exhaust
State.But the problem of local biphase gas and liquid flow occur in passage intake and exhaust and tailwater tunnel is also brought simultaneously, into pipeline
Air mass through overcompression, expansion, be then exhausted from bringing larger transient pressure during aperture, and with water spray phenomenon, whole transient process compared with
For complexity, some new hydrodynamicses and thermodynamic problems are occurred in that, if design or running improper, can be produced in the transient process
More serious pressure oscillation is given birth to, the lighter's influence stable operation of unit, serious results even in the serious accident that tunnel is destroyed,
Cause the loss for being difficult to retrieve.
When passage is in intake and exhaust state, the minimum negative pressure and highest malleation of the area of passage for tailwater tunnel
With considerable influence.When hole area of ventilating is larger, breathing action is very fast, and air inlet is conducive to the effective of negative pressure in tunnel soon
Alleviate, be vented the shock pressure produced soon larger；When hole area of ventilating is smaller, breathing action is relatively slow, is unfavorable for tunnel
The alleviation of middle negative pressure, but the shock pressure of exhaust finish time is smaller.Therefore, the size of rational selection passage, is needed
Consider larger malleation when minimum negative pressure and the passage exhaust in tailwater tunnel.In current design, all adopt substantially
With the ventilation hole area of fixed size, it is impossible to balance the contradiction between minimum negative pressure and maximum positive voltage well, the present invention is used
A kind of new ventilation well format, has coordinated the minimum negative pressure and instantaneous maximum positive voltage of tailwater tunnel well.
The content of the invention
Goal of the invention：The tailwater tunnel ventilation well format that area is fixed in the prior art, exists and is difficult to minimum to bear simultaneously
Pressure and maximum positive voltage control the deficiency in preferably scope.In order to overcome this shortcoming of fixed-area passage, improve tail water
Pressure in tunnel, it is ensured that the safe and reliable operation in power station, the present invention is intended to provide a kind of improve the ventilation of tailwater tunnel pressure
Aperture apparatus：The ventilation well format of Unidirectional flow-limiting, the size for hole area of being ventilated during by adjusting air inlet and exhaust, to improve tail water tunnel
Pressure in hole.
Technical scheme：In order to solve the above technical problems, a kind of passage for improvement tailwater tunnel pressure that the present invention is provided
There is two-way air port and unidirectional ventilating opening, institute on device, including the panel in tailwater tunnel passage, the panel
Stating two-way air port is used for the air inlet and exhaust of tailwater tunnel, and the unidirectional ventilating opening has the unidirectional of limitation tailwater tunnel exhaust
Backstop structure.
Specifically, the one-way check structure includes the column being fixed on panel, is set in the choke lid on column, with
And choke lid is covered the spring of unidirectional ventilating opening.When air flows out tailwater tunnel, the choke lid covers unidirectional ventilating opening,
Area during air outflow is reduced, further the outflow of limitation air.
Specifically, bearing is installed between column and the choke lid, the contact site of the panel and choke lid is provided with
Rubber blanket.Bearing can reduce the friction during movement of choke lid.Rubber blanket plays cushioning effect, it is to avoid choke lid is closed and opened
When destroyed due to excessive velocities.
Specifically, the column is three be distributed at unidirectional ventilating opening edge in equilateral triangle.Choke lid level can be made
Decline, prevent from tilting.
Specifically, by the derivation of equation, passage, choke lid, column each several part dimension and weight are calculated, and pass through meter
The length for determining column is calculated, when choke lid reaches least significant end, it is to avoid long its ultimate strength that exceedes of spring elongation makes spring quilt
Draw bad, it is impossible to retract choke lid：
The length L=L of column1+L2+b
The height h=L of choke cover plate1+b
In formula, the tensile elongation of spring when wind speed v is 0The weight m of choke lid, the coefficient of elasticity k of spring, bullet
The initial length b of spring；When air is flowed into from top to bottom, by the area A of unidirectional ventilating opening, a diameter of D, air resistance coefficient is c, wind
To the thrust of choke lidThe tensile elongation of spring
Specifically, unidirectional ventilating opening edge is provided with the projection of choke lid on the panel.Covered completely in choke lid
When ensure air not recirculation.
Specifically, the Installation Elevation of the panel is in passage more than maximum water level.The water in passage is not influenceed
Body flows and fluctuation of surging.
Present invention simultaneously provides the method for work of the vent device of above-mentioned improvement tailwater tunnel pressure, it is characterised in that：
When transient process occurs for power station, pressure and surge change in tail water road, under atmospheric pressure, air is via ventilation
Hole enters tailwater tunnel from top to bottom；At panel, air flows down, choke lid opens unidirectional ventilating opening, and air is from double
It is co-flowed into ventilating opening and unidirectional ventilating opening, slows down the negative pressure in tailwater tunnel；
When the water surface rises in tailwater tunnel, the air in tunnel by passage discharge line, at panel air to
Upper motion, in the presence of air and spring, choke lid closes unidirectional ventilating opening, and now air can only pass through middle two-way
Air port is discharged, transient pressure during reduction air mass delivery port.
The present invention theoretical foundation be：Ventilating, hole area is bigger, and intake process is faster, slows down tailwater tunnel vacuum effect and gets over
It is good.From the angle, it is desirable to which hole area of ventilating is the bigger the better.But ventilation hole area is bigger, exhaust process is also faster, produces
Shock pressure it is also relatively large.Tailwater tunnel peak suction, maximum shock pressure and engineering are considered in engineering design
The multinomial factor such as arrangement determines ventilation hole area.By tailwater tunnel passage operation principle and it is described above it can be seen from compared with
Excellent vent hole structure form is：The tunnel stage is flowed into air, orifice area is larger, air inlet is very fast, meets tailwater tunnel most
Lower negative pressure requirement；The tunnel stage is discharged in air, orifice area is smaller, be vented more slow, satisfaction shock pressure requirements, so that
Improve the pressure of tailwater tunnel on the whole.
Inventive principle：By taking Transient Process of Hydropower Station as an example, illustrate to be provided with two-way air port and unidirectional ventilating opening panel
The operation principle and effect of Unidirectional flow-limiting passage.
When transient process occurs for power station, pressure and surge change in tail water road relatively acutely, may result in compared with
Water surface reduction in eminence tailwater tunnel, produces low pressure.Under atmospheric pressure, air enters from top to bottom via passage
Tailwater tunnel.At panel, air flows down.In the presence of air, choke lid is quickly moved down, now unidirectional ventilation
Mouth is opened, and air can be co-flowed into from two-way air port and unidirectional ventilating opening, and intake velocity is very fast, can be very good to slow down tail
Negative pressure in water tunnel.
When the water surface rises in tailwater tunnel, the air in tunnel passes through passage discharge line.At panel, air to
Upper motion.In the presence of air and spring, choke lid is quickly moved up, and closes unidirectional ventilating opening, and now air can only lead to
Two-way air port discharge in the middle of crossing, exhaust velocity is slower, can effectively reduce transient pressure during air mass delivery port.
Beneficial effect：Compared with prior art, the present invention is efficiently solved in Hydropower Plant transient process, due to tail
There is larger transient pressure when water level reduction produces excessive negative pressure and water level ascending air discharge tailwater tunnel aperture in water tunnel
The problem of, this structure type to passage further optimizes, and the raising of power station regulation quality and flexible stable operation have
Very significant effect.
Except the technical problem of invention described above solution, the technical characteristic of composition technical scheme and by these skills
Outside the advantage that the technical characteristic of art scheme is brought, a kind of vent device of improvement tailwater tunnel pressure of the invention can be solved
The advantage that the other technical characteristics and these technical characteristics included in other technologies problem certainly, technical scheme are brought, will be tied
Accompanying drawing is closed to be described in more detail.
Brief description of the drawings
Fig. 1 is existing tailwater tunnel vent hole structure schematic diagram；
Fig. 2 is tailwater tunnel vent hole structure schematic diagram of the invention；
Fig. 3 is panel construction top view of the invention；
Fig. 4 is the top view of unidirectional ventilating opening in Fig. 3；
Fig. 5 is front view when Fig. 3 is in opening；
Fig. 6 is front view when Fig. 3 is closed；
Fig. 7 is Fig. 3 relative dimensions schematic diagrames；
Fig. 8 arranges sketch for the power station water-carriage system of the embodiment of the present invention；
Fig. 9 arranges sketch for the hydropower station tail water system of the embodiment of the present invention；
Figure 10 is pressure change graph at passage of the embodiment of the present invention；
In figure：Tailwater tunnel 1, passage 2, panel 3, two-way air port 4, unidirectional ventilating opening 5, choke lid 6, spring 7 is stood
Post 8, bearing 9, rubber blanket 10.
Embodiment
Embodiment：
The present embodiment is used to improve the vent device of tailwater tunnel pressure as shown in Figures 2 and 3, in tailwater tunnel 1
The top of passage 2 set panel 3.Panel 3 is provided with unidirectional ventilating opening 5 and two-way air port 4, and wherein two-way air port 4 can
Bidirection air intake, unidirectional ventilating opening 5 allows air to flow into from top to bottom, when air from bottom to top flows out, in wind-force and spring
In the presence of pulling force, cover plate covers unidirectional ventilating opening 5, prevents the outflow of air.By the effect of two kinds of passages, can be achieved by
The quick air inlet into tailwater tunnel 1 of passage 2, slows down the negative pressure in tunnel；Tailwater tunnel 1 is slowly vented to passage 2, drop
Transient pressure during low air mass delivery port.
Unidirectional ventilating opening structure form as shown in Figure 4, Figure 5, Figure 6 and Figure 7, uses the phase of spring 7 between choke lid 6 and panel 3
Even, be in contact position setting rubber blanket 10, is provided with column 8 in the middle of spring 7, choke lid 6 is connected with column 8 with bearing 9, column
Bottom expands, and upper surface is provided with rubber blanket 10.Spring initial length is b, and the weight of choke cover plate is m, the coefficient of elasticity of spring
For k, air resistance coefficient is c, and the area of unidirectional ventilating opening is A, a diameter of D, then the tensile elongation of spring when wind speed v is 0
The height h=L of choke cover plate1+b。
When air is flowed into from top to bottom, thrust of the wind to choke lidNow the tensile elongation of spring isTherefore the length L=L of column1+L2+b。
When choke lid is moved to the top or bottom, choke lid and panel or column contact site are provided with rubber
Rubber cushion, it is to avoid the too fast destruction that collides of choke lid movement velocity.
When removal of load operating mode occurs for unit, liquid level declines in tailwater tunnel, and pressure reduction, ambient pressure is more than tail water tunnel
Hole pressure, air flows into tailwater tunnel by ventilating opening from top to bottom.At panel, air-flow blows choke lid and moved downward, i.e.,
Unidirectional ventilating opening is opened.Air can enter tailwater tunnel by two-way air port and unidirectional ventilating opening, and air inlet area is larger, therefore mend
Gas speed, can alleviate the negative pressure of tailwater tunnel in time.
When liquid level rises in tailwater tunnel, the air being originally present in tunnel is compressed, and air pressure increase is big more than extraneous
Air pressure, air excludes tailwater tunnel via passage from bottom to top.At panel, air-flow blows choke lid and moved upwards, i.e., single
Closed to ventilating opening.Air can only discharge tailwater tunnel by unidirectional ventilating opening, and leaving area is smaller, therefore exhaust velocity is more delayed
Slowly, transient pressure during air mass delivery port is greatly reduced.
Certain water channeling type power station piping upstream is using the arrangement form of " single tube unit ", and tail water discharge is using " three machines one
The arrangement form in the hole of room one ", its Hydraulic unit horizontal layout are as shown in figure 8, L in figure11Section and L12Section section arrangement is such as Fig. 9 institutes
Show, passage is arranged in tailwater tunnel and diversion tunnel junction.
The present embodiment is by setting different ventilation hole areas and using the vent hole structure in the present invention, comparing this power station
When removal of load simultaneously occurs for three units, the pressure change at tailwater tunnel passage, specific result of calculation is as shown in Figure 10.
As shown in Figure 10, when from New type ventilating pore structure, the pressure of tailrace tunnel is well controlled, and avoids substantially
The shock pressure of exhaust finish time.When unit starts removal of load, the pressure in tailwater tunnel is begun to decline.When using biography
During the vent hole structure of system, air inlet area is identical with leaving area, and larger shock pressure occurs after terminating for exhaust process, and it is pressed
Force value reaches 47.90m, is unfavorable for the safe operation of tailwater tunnel.And when from new vent hole structure, pressure is obtained very
Control well.Breathing area is larger during air inlet, minimum pressure that can be in rapid recovery tunnel, and breathing area reduces during exhaust,
The velocity of discharge of mitigation of gases, it is 21.32m that maximum, which hits pressure, well below the pressure value under conventional ventilation pore structure so that
Pressure oscillation is preferably controlled.
The above results show：Aperture is fully open during New type ventilating pore structure, i.e. air inlet proposed by the present invention, and exhaust only has
Part aperture is vented, and pressure oscillation is preferably controlled, and protects the safety of tunnel.
Present invention employs the structure that panel is set in passage, the opening in the middle of panel is regard as two-way air port；
The osculum that surrounding is opened is as unidirectional ventilating opening.Unidirectional ventilating opening is provided with choke lid below panel, and choke lid is groove shapes knot
Structure, is connected with spring, and spring upper end is fixed on panel, and lower end is connected with choke lid.There are column, choke lid and column in the middle part of spring
Between have a rolling bearing, column bottom is increased, and prevents choke lid displacement is excessive from causing spring to exceed its ultimate strength.Bottom upper table
Face is provided with rubber blanket, it is to avoid because excessive velocities are destroyed when choke lid is opened.Unidirectional ventilating opening can limit air and pass through
Passage is flowed upwards out, i.e., when air flows from top to bottom, and unidirectional ventilating opening is opened, and air can be from unidirectional ventilating opening and two-way
Air port is flowed into；When air flows from bottom to top, unidirectional ventilating opening is closed, therefore air can only flow out from two-way air port.
Embodiments of the present invention are described in detail above in association with accompanying drawing, but the present invention is not limited to described reality
Apply mode.For one of ordinary skill in the art, in the range of the principle and technological thought of the present invention, to these implementations
Mode carries out a variety of changes, modification, replacement and deformation and still fallen within protection scope of the present invention.
Claims (5)
1. a kind of improve the vent device of tailwater tunnel pressure, including the panel in tailwater tunnel passage, it is special
Levy and be：There is two-way air port and unidirectional ventilating opening, the two-way air port is used for the air inlet of tailwater tunnel on the panel
And exhaust, the unidirectional ventilating opening, which has, limits the one-way check structure that tailwater tunnel is vented, and the one-way check structure includes
The column on panel is fixed on, the choke lid on column, and the spring for making choke lid cover unidirectional ventilating opening is set in.
2. a kind of vent device of improvement tailwater tunnel pressure according to claim 1, it is characterised in that：The column
Bearing is installed between choke lid, the contact site of the panel and choke lid is provided with rubber blanket.
3. a kind of vent device of improvement tailwater tunnel pressure according to claim 1, it is characterised in that：It is described vertical
Post is three be distributed at unidirectional ventilating opening edge in equilateral triangle.
4. a kind of vent device of improvement tailwater tunnel pressure according to claim 1, it is characterised in that：
The length of columnL=L 1 +L 2 +b
The height of choke cover plateh= L 1 +b
In formula, wind speedvFor 0 when spring tensile elongation, the weight of choke lidm, the coefficient of elasticity of springk, spring
Initial lengthb；When air is flowed into from top to bottom, by the area of unidirectional ventilating openingA, it is a diameter ofD, air resistance coefficient isc, wind is to resistance
The thrust of gas lid, the tensile elongation of spring。
5. a kind of vent device of improvement tailwater tunnel pressure according to claim 1, it is characterised in that：The panel
Upper unidirectional ventilating opening edge is provided with the projection of choke lid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610218295.9A CN105821819B (en) | 2016-04-08 | 2016-04-08 | It is a kind of to improve the vent device of tailwater tunnel pressure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610218295.9A CN105821819B (en) | 2016-04-08 | 2016-04-08 | It is a kind of to improve the vent device of tailwater tunnel pressure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105821819A CN105821819A (en) | 2016-08-03 |
| CN105821819B true CN105821819B (en) | 2017-08-15 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201610218295.9A Active CN105821819B (en) | 2016-04-08 | 2016-04-08 | It is a kind of to improve the vent device of tailwater tunnel pressure |
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Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110080926B (en) * | 2019-05-05 | 2024-05-07 | 黄河勘测规划设计研究院有限公司 | Impact type turbine set structure for increasing power generation water head |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2049196C1 (en) * | 1992-11-17 | 1995-11-27 | Николай Викторович Арефьев | Compensating basin of pressure high-line conduit of hydroelectric power station |
| CN103062451A (en) * | 2011-10-24 | 2013-04-24 | 温永林 | One-way valve |
| CN202972060U (en) * | 2012-11-29 | 2013-06-05 | 路汉芝 | Adjustable automatic exhaust one-way valve |
| CN104060591B (en) * | 2014-07-15 | 2016-06-01 | 中国电建集团中南勘测设计研究院有限公司 | A kind of power station pressure regulation well |
| CN204282317U (en) * | 2014-11-17 | 2015-04-22 | 中国电建集团成都勘测设计研究院有限公司 | Power station free pressure flow replaces tailrace tunnel |
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2016
- 2016-04-08 CN CN201610218295.9A patent/CN105821819B/en active Active
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| CN105821819A (en) | 2016-08-03 |
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| EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20160803 Assignee: PowerChina Huadong Engineering Corp.,Ltd. Assignor: HOHAI University Contract record no.: X2021320000023 Denomination of invention: A vent device for improving the pressure of tailrace tunnel Granted publication date: 20170815 License type: Common License Record date: 20210316 |
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| EE01 | Entry into force of recordation of patent licensing contract |