CN201473934U

CN201473934U - Diversion pier type differential surge chamber

Info

Publication number: CN201473934U
Application number: CN2009201921323U
Authority: CN
Inventors: 侯靖; 吴旭敏; 潘益斌; 陈晓江
Original assignee: Hydrochina East China Engineering Corp
Current assignee: Hydrochina East China Engineering Corp
Priority date: 2009-08-31
Filing date: 2009-08-31
Publication date: 2010-05-19
Anticipated expiration: 2019-08-31

Abstract

The utility model relates to a diversion pier type differential surge chamber. For solving technical problems, the utility model provides the diversion pier type differential surge chamber which has the advantages of simple structure and small work amount and can improve stress distribution condition of the bottom plate of the surge chamber under hydraulic pressure differential, so as to improve the structural security of the entire surge chamber. The utility model adopts the technical scheme that the diversion pier type differential surge chamber is provided with a diversion tunnel, the upper part of the diversion tunnel is communicated with a riser arranged vertically, the top end of the riser is communicated with a large well of the surge chamber, and the bottom end of the riser is communicated with the bottom part of the large well of the surge chamber through a backflow hole. The utility model is characterized in that a diversion pier connected to be a whole with the bottom plate of the surge chamber is arranged in the middle position of the derivation tunnel. The utility model is mainly used in hydraulic and hydro-power engineering, particularly in water-power engineering with large discharge, long derivation tunnel and high capacity.

Description

The differential surge-chamber of baffle pier formula

Technical field

The utility model relates to the surge-chamber that uses in a kind of Hydraulic and Hydro-Power Engineering, the differential surge-chamber of particularly a kind of baffle pier formula.Mainly be applicable in the various Hydraulic and Hydro-Power Engineerings particularly big flow, long diversion tunnel, jumbo hydroelectric project.

Background technology

The long diversion tunnel engineering of field of water conservancy; in diversion tunnel end, pressure piping stem the upstream surge-chamber must be set; avoid or be subjected to water hammer pressure less with the protection diversion tunnel; alleviate the water hammer pressure in the pressure pipeline of downstream; supply with the hydraulic turbine simultaneously and increase the needed water yield when loading; the water-level fluctuation of whole channel system when regulating unit operation obtains best quality of regulation.According to the hydraulic action and the structural configuration situation of surge-chamber, the surge-chamber that adopts in actual engineering has following several pattern: prismatic simple surge-chamber, the surge-chamber that has the expansion chamber, simple resistance cellular type surge-chamber, differential surge chamber and have the resistance cellular type surge-chamber of expansion chamber.

Surge-chamber is a waterpower adjustment building commonly used in the Hydraulic and Hydro-Power Engineering, differential surge chamber is superior as a kind of hydraulic performance, the big characteristic surge-chamber of surge-chamber the water-level fluctuation rapid and minimum safety margin of surging of decay, the riser and the big well construction on main and carry potential overflow weir less by diameter, the bottom is provided with the impedance hole and communicates with Da Jing, and its water-level fluctuation is by the area common guarantee of riser and big well.Because the riser diameter is little, the riser fluctuation in stage is rapid, and the flow velocity that can change faster in the derivation conduit is quoted the needs of flow to adapt to the hydraulic turbine after the load variations.The spilling water at riser top drops to Da Jing and returns riser all with bigger energy loss with the retaining of big well by return apertures simultaneously, therefore it is rapider than the surge-chamber water-level fluctuation decay of any other pattern, has improved the stability and the power supply quality of power station unit operation.Liu Xi river, the government office that China has built, the mountain range of getting down from horse, lion beach, Huang Tankou, Gutian I and II, with before three grades in gift river, the natural bridge secondary remodeling, power station such as big flat post all adopts differential surge chamber.But the pressure diversion system is arranged for one, when the flow in the system changed, the water level in the surge-chamber was with the generating period variation.Sometime water level and the head difference that forms of the pressure head in the runner in the surge-chamber directly acts on the base plate of surge-chamber as water ballast(ing).For having the power station of the diversion system of growing up, in diversion and power system generation waterpower transient process, the generating period SEA LEVEL VARIATION is rapider in the differential surge chamber, the pressure reduction that base plate bears is bigger, the huge often surge-chamber of the differential surge chamber of the tunnel correspondence of particularly growing up, surge-chamber base plate span is big, and the surge-chamber base arrangement safety of bearing huge pressure reduction is a very crucial problem, usually becomes the major influence factors whether surge-chamber selects the differential type pattern.

Summary of the invention

The technical problems to be solved in the utility model is: provide a kind of simple in structure, differential surge-chamber of baffle pier formula that engineering quantity is little at the problem of above-mentioned existence, improve the stressed distribution situation of surge-chamber base plate under the hydraulic pressuring difference effect, to improve the safety of structure of whole surge-chamber.

The technical scheme that the utility model adopted is: the differential surge-chamber of baffle pier formula, has diversion tunnel, its top is communicated with the riser of vertically arranging, the riser top is communicated with the big well of surge-chamber, the bottom is communicated with by the big bottom of return port and surge-chamber, it is characterized in that: the centre position is provided with the baffle pier that fuses with the surge-chamber base plate in the described diversion tunnel.

Described baffle pier upstream extremity is streamlined nose shape.

Described riser is to place the surge-chamber big well outside and be mounted in the interior Emergency Gate well of country rock, and concrete riser partition wall is set between the big well of riser and surge-chamber, and this riser partition wall two sides is inwardly recessed circular arc, formation concave mirror shape.

Described return port is asymmetric return port, and it is streamlined to be horn mouth in close riser side, is extension near the big well side of surge-chamber.

The beneficial effects of the utility model are: the utility model centre position in diversion tunnel is provided with the baffle pier that fuses with the surge-chamber base plate, guaranteeing that the tunnel electrical generation water is flow to end under the smooth-going prerequisite of possibility bottom the surge-chamber, the big shaft bottom span of slab of whole differential surge chamber can be reduced half, because square being directly proportional of base plate bending moment and span, the shearing of base plate is directly proportional with span, therefore reduce big shaft bottom span of slab, can improve the stressed distribution situation of surge-chamber base plate under the hydraulic pressuring difference effect at double, and optimized the structure of surge chamber vertical shaft base plate, increased substantially the reliability of whole engineering structures safety, widen the suitable works limit of differential surge chamber, improved electrical network and unit operation restrictive condition greatly.

Description of drawings

Fig. 1 is a main sectional view of the present utility model.

Fig. 2 is a sectional view of the present utility model.

Fig. 3 is that the A-A of Fig. 2 is to sectional view.

Fig. 4 is that the B-B of Fig. 2 is to sectional view.

The specific embodiment

As Fig. 1, shown in Figure 2, comprehensively build, the layout experience of project under construction surge-chamber, present embodiment is provided with above diversion tunnel 8 and is attached thereto riser 3 logical and that vertically arrange, be communicated with by overflow weir between riser 3 tops and the big well 6 of surge-chamber, the bottom is communicated with the big well of surge-chamber 6 bottoms by return port 5, the centre position is provided with the baffle pier 1 that fuses with surge-chamber base plate 2 in the described diversion tunnel 8, baffle pier 1 upstream extremity is streamlined nose shape in this example, guarantee surge-chamber bottom diversion tunnel 8 electrical generation water flow to end may shunt smooth-going, under the little prerequisite of head loss, the layout of baffle pier 1 makes surge-chamber base plate 2 spans be reduced to original half, make original single span frame construction be optimized to double-span frame structure, surge-chamber base plate 2 is linked to be overall structure by baffle pier 1 and diversion tunnel 8 base plates, unite stressed, bear upwards with in the process of launching stress load at surge-chamber base plate 2, part Load Transfer is given diversion tunnel 8 both sides abutment walls, another part load passes to diversion tunnel 8 base plates of its bottom by baffle pier 1, diversion tunnel 8 base plates are linked to be integral body with the surge-chamber base plate 2 at diversion tunnel 8 both sides abutment walls and top again, make the bending resistance of surge-chamber base plate 2, shear-carrying capacity significantly improves, stress form is more reasonable, the safety of structure, durability significantly improves, and structure scheme is coordinated rationally.

In this example with riser 3 and Emergency Gate well in conjunction with layout, be about to Emergency Gate well double as riser 3, and riser 3 placed the big well of surge-chamber 6 outsides, make it to be mounted in the country rock, reduce the free face of towering riser 3, improve the structural stability and the safety of riser 3.Simultaneously between riser 3 and the big well 6 of surge-chamber, steel concrete riser partition wall 4 is set, and riser partition wall 4 two sides are inwardly recessed circular arc, form concave mirror shape, so that under forward and reverse pressure reduction load action, all can form arching, the raising supporting capacity.As shown in Figure 3, Figure 4, in this example, two risers 3 of big well 6 outside symmetric arrangement of surge-chamber, form the Y font, and each riser 3 top all is communicated with by the big well 6 of overflow weir and surge-chamber, the bottom all is communicated with by the big well 6 of return port 5 and surge-chamber, and corresponding diversion tunnel 8 is two pressure pipings 9 at the downstream fork, forms the Y font.Two risers 3 are arranged in the junction of diversion tunnel 8 and two pressure pipings 9.

Described return port 5 is asymmetric return port, be that return port 5 is being designed to horn mouth streamlined structure build near riser 3 sides, be designed to extension 7 builds near big well 6 sides of surge-chamber, its diameter is identical with return port 5 straight hole section diameters, can make current be about 1.2 like this from the forward flow velocity damped coefficient that riser 3 flows into the big well 6 of surge-chamber, and current are about 1.7 from the reverse flow damped coefficient that the big well 6 of surge-chamber flows into riser 3, above-mentioned damped coefficient is after build is determined, be a definite value in the stock size scope, obtain by model testing.If return port is symmetrical aperture, then positive and negative flow velocity damped coefficient is about 1.5).Because current flow into the forward deattenuation of the big well 6 of surge-chamber from riser 3, be equivalent to strengthen the orifice area that becomes a mandarin, water pressure in the riser 3 can significantly reduce, thereby reduces the hydraulic pressuring difference load of the big well 6 of riser 3 relative surge-chambers, and has reduced the hydraulic pressuring difference load of surge-chamber base plate 2.Current increase from the reverse flow damping that the big well 6 of surge-chamber flows back to riser 3, be equivalent to reduce the flow-out hole open area, thereby strengthened the characteristic of surging under the big well 6 of surge-chamber anti-, improve the ability of the big well 6 water level tension skies of surge-chamber, made power station unit operation restrictive condition further improve.The waterpower fluctuation total damping of surge-chamber is all relevant with return port 5 positive and negative two water (flow) directions, and a direction reduces and another direction increase, and total damping still can be constant substantially.In addition, asymmetric return port 5 is set, has effectively avoided surge-chamber base plate 2 that the weakening of impedance hole to base arrangement globality and intensity is set, further improved the safety of structure of differential surge chamber in the bottom of riser 3.

The operating principle of present embodiment is: when surge-chamber generation upsurge, current at first flow into by riser 3 bottom plate rabbets in the diversion tunnel 8, make riser 3 middle water levels raise rapidly and surpass the overflow weir elevation at riser 3 tops, and to big well 6 overflows of surge-chamber, diversion tunnel 8 interior current flow into the big well 6 of surge-chambers by the asymmetric return port 5 of riser 3 bottoms simultaneously, the current that overflow with riser 3 tops, water level in the big well 6 of surge-chamber is progressively risen, in this process, surge-chamber base plate 2 produces huge upward hydraulic pressure load.When the water level in the big well 6 of surge-chamber with after water level in the riser 3 flushes substantially, the process of surging under surge-chamber begins, along with the current in the diversion tunnel 8 begin to reflux, cause the water level in the riser 3 to reduce rapidly, water body in the big well 6 of surge-chamber flows into riser 3 by the asymmetric return port 5 of riser 3 bottoms, and flows back to diversion tunnel 8 through riser 3 bottom plate rabbets, and big well 6 water levels of surge-chamber progressively descend, in this process, surge-chamber base plate 2 produces huge to the launching stress load.

Claims

1. differential surge-chamber of baffle pier formula, has diversion tunnel (8), its top is communicated with the riser of vertically arranging (3), riser (3) top is communicated with the big well of surge-chamber (6), the bottom is communicated with the big well of surge-chamber (6) bottom by return port (5), it is characterized in that: the interior centre position of described diversion tunnel (8) is provided with the baffle pier (1) that fuses with surge-chamber base plate (2).

2. the differential surge-chamber of baffle pier formula according to claim 1 is characterized in that: described baffle pier (1) upstream extremity is streamlined nose shape.

3. the differential surge-chamber of baffle pier formula according to claim 1 and 2, it is characterized in that: described riser (3) is for placing outside the big well of surge-chamber (6) and being mounted in the interior Emergency Gate well of country rock, between riser (3) and the big well of surge-chamber (6) concrete riser partition wall (4) is set, and this riser partition wall (4) two sides is inwardly recessed circular arc, forms concave mirror shape.

4. the differential surge-chamber of baffle pier formula according to claim 1 and 2 is characterized in that: described return port (5) is asymmetric return port, and it is streamlined to be horn mouth in close riser (3) side, is extension (7) near the big well of surge-chamber (6) side.

5. the differential surge-chamber of baffle pier formula according to claim 3, it is characterized in that: described return port (5) is asymmetric return port, it is streamlined to be horn mouth in close riser (3) side, is the diameter extension (7) identical with return port (5) straight hole section near the big well of surge-chamber (6) side.