RU2557184C1 - Water flow energy dissipator - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: water flow energy dissipator includes water line 1, pressure pipelines 2 provided with swirling devices 3. Pipelines 2 are connected with outlet sections to closed housing 5 in the form of a chamber towards each other. Mixing chamber 6 of a square cross-section is located under housing 5. Baffle wall 7 of chamber 6 has concave pressure face 8 made so that it faces upwards and to the side of outlet sections of pipelines. At the mixing chamber outlet point, a discharge channel is covered with plate 16 connected to partition wall 11. Baffle wall 7 of chamber 6 has inclined hole 9 attaching chamber 6 to discharge channel 10 and directed towards partition wall 11. Partition wall 11 is intended for changing the direction of the flow leaving outlet hole 15 of mixing chamber 6 to discharge channel 10, where jet flow from inclined hole 9 is connected to one common flow, which reduces bottom velocities after partition wall 11. Closed housing 5 is also provided with pipe 13 with gate valve 14 for pressure supply of air or atmosphere.

EFFECT: improving efficiency and reliability of dissipation of kinetic energy of the separated and again joint flow; high protection degree of a discharge channel against dynamic effects provided by air accumulations opening to the lower pool, which improves reliability of a water flow energy dissipator, reduces length of the closed section of the discharge channel and excludes the need of a well device for the lower pool of the channel.

2 cl, 2 dwg

Description

The invention relates to hydraulic engineering, hydraulics, hydromechanics, and more particularly, to hydraulic structures designed to extinguish energy after pressure pipelines in the receiving chamber.

Known energy absorbers of the flow SU 1030474, ЕОВВ 8/06, 07/23/1983, SU 1043246, ЕВВ 8/06, 09/23/1983, SU 1569375, ЕВВ 8/06, 06/07/1990. As a result of the splitting of the stream into jets and their collision, a drop in the flow velocity occurs, resulting in an intense quenching of its energy.

Known flow energy damper, including a cylindrical water well, a flow divider in two branches, tangentially connected to the well, the damper plates are mounted on racks with the possibility of vertical movement and are made with walls located around their perimeter (Copyright certificate SU 1059054, ЕОВВ 8/06 12/07/1983).

The disadvantage of this design is that it is complicated by the design of plates associated with unloading containers filled with water. At the same time, impact on the fastening elements of the outlet channel is not excluded, which means that it does not contribute to sufficient damping and smoothing of the water surface in the outlet channel. The difference in elevations does not allow to flood the hydraulic jump that forms when the liquid falls. Thus, the efficiency of quenching the flow in the outlet channel is insufficient. In addition, the complexity of the design of slabs from complex reinforced concrete work requires the stability of their ascent in a vertical position, limited by struts, while they can jam during movements, since the force of the resultant hydrostatic pressure in the well at different points occurs unevenly across the entire pressure plane of the slabs.

Also known is a flow energy damper, including a water conduit, a swirling device that separates the flow into jets, and a discharge channel (Copyright certificate SU 1712530, EV 8/06, 02/15/1992).

A disadvantage of the known damper is that when the device swirls the flow in horizontal sections in the damper chamber, intense pulsation of velocities and pressures occurs, as well as incomplete damping of the kinetic energy of the flow in the discharge channel. The jets of water flowing from the well are directed almost in one direction, therefore, their impact ineffectively extinguishes the flow energy. At the same time, the concatenation of the downstream is carried out according to the type of a driven off jump, on which the fastening section of the bottom of the outlet channel is not calculated, which leads to unacceptable erosion. In addition, the presence of such a flow stream before leaving the hole does not reduce the bottom velocity in the outlet channel and creates wave surface phenomena, which reduces the hydraulic operating conditions of the outlet channel.

Known spillway, including a tower with a drain hole and a discharge pipe, the upper part of the tower is closed by a sealed cover and equipped with an air duct with shutoff valves installed in a sealed cover and communicating the cavity under the cover with the atmosphere (Copyright certificate SU No. 1011772, ЕОВВ 8/06 dated 15.04. 1983).

In the described construction, the tower does not create a rotational movement of the water flow in the vertical shaft, therefore, the length of the outlet pipe increases, which creates a pressure in it for working with a full cross section. The flow in the shaft must actually always be flooded for the end of the duct. However, this is not always possible, since the upper level can change frequently, respectively, the hole in the duct is taken with a calculation at a mark not lower than the normal backed level. Another disadvantage is that a large amount of air is released from the water under the cover, which negatively affects the mine's throughput, pressure on the mine walls increases, and hydrodynamic loads occur. In addition, this shaft construction is connected to a discharge pipe, in which formation of air accumulations under the pipe ceiling is possible, which is a consequence of deaeration of the flow, in the absence of a deepening of the end of the discharge pipe to the level of the downstream. The accumulation of air is moved by the stream, and the exit from the spillway is accompanied by a hydraulic shock, which can lead to the destruction of the structure. In addition, such air resistance in the pipe causes a decrease in throughput in the entire spillway. Therefore, such structures are built with a large margin of safety or should limit the mode of their operation in such a way as to exclude the formation of air accumulations on the tract. Both lead to a rise in the cost of the spillway as a whole.

Known flow rate damper for sedimentation tanks, including inlet and outlet channels and a water intake chamber located between them, made in the form of a pipe perpendicular to the axis of the damper with a top hole overlapped by a curved plate articulated above it, facing the concave side to the chamber, the pipe is located at the bottom level the outlet channel and is made with two lateral horizontal holes oriented towards the downstream side, while the plate is fixed to the chamber with the bottom torons, and opposite the lateral holes water-baffle walls are installed (Copyright certificate SU No. 1682458, ЕВВ 8/06, dated 07.10.1991).

However, this absorber is inoperative at high pressures. In addition, it is intended mainly for the control of sediment. In addition, the manufacture of a curvilinear plate requires an expensive scarce metal, and a stream having a sufficiently large kinetic energy can cause the plate to detach from the axis of rotation, i.e. the device is unreliable. The next drawback is also the main one, because the low reliability of the quenching of kinetic energy, due to the straightforwardness of the flows moving towards each other at the point of convergence of the rigidly fixed water-breaking walls, through the top of which the overflow also occurs simultaneously (this is noted by the authors themselves in the description).

The high randomly probable unidirectionality of colliding flows in the outlet channel, leading to the summation of the kinetic energy in the center between the rigid water-retaining walls fixed to the bottom, forms a rise of water upward, which causes large bursts and waves behind them when the flow expands, erosion of the channel slopes, which reduces the efficiency and the reliability of the quenching of the water flow (this is confirmed by the invention according to AS SU No. 1550033, cl. EB 8/06 of 03/15/1990). Thus, the efficiency of quenching the excess kinetic energy of the flow in the known device is significantly reduced, while having a large metal consumption and determines stringent requirements for the design of the damper.

The closest technical one to the proposed one is a spillway, including a mixing chamber located in the body of the retaining structure above the downstream channel, pressure galleries with gates connected to the upper pool and connected to the mixing chamber towards each other, an air duct connecting the mixing chamber with the atmosphere, a water chamber, located under the mixing chamber, and a discharge water conduit connecting the water chamber to the downstream, while it is equipped with a transverse water wall installed in the water slaughter a chamber under the mixing chamber and made with a concave face turned upward and upstream into a quarter of a cylindrical surface, the radius of which is equal to the length of the mixing chamber (Author's certificate SU No. 1504307, ЕОВВ 8/06 of 08/30/1989).

The disadvantage is that after the collisions of the flows in the mixing chamber in the water chamber, there is no noticeable rotation to a greater extent, which mainly departs from the center of the chamber, flattening of the rotating flow is formed due to the rectangular shape of the chamber in cross section, i.e. The square shape of the camera is missing. Another disadvantage is that in the body of the retaining structure - the dam, the chamber is connected to the outlet conduit in the form of a pipe with flooding from the downstream to reduce the kinetic energy of the stream leaving the conduit. However, in such water conduits - this is a small capacity of flooded with exhaust air, in which the movement of the flow occurs in the form of cork flow in it. Thus, from the outlet (slot) in the water chamber, the outlet is located closer to the ceiling of the outlet pipe (water conduit), air accumulation occurs, since the downstream is flooded, and such plugs cannot be completely eliminated. In addition, the possibility of water hammer is not excluded, which negatively affects the reliability of the structure as a whole, and it is not effective enough when working in the open channel mode due to design flaws.

The technical result from the use of the claimed invention is to increase the reliability by reducing the dynamic loads that accompany the exit to the downstream of the air congestion and reduce material consumption.

The technical result is achieved in that in a water flow energy absorber including a water conduit, pressure pipelines provided with swirling devices and connected to a closed casing in the form of a chamber facing each other, a mixing chamber is located under the casing, the wall of which has an outlet, the water-supply wall of the mixing chamber has a concave face from the side of the outlet in which the inclined hole is made, the mixing chamber is made of square cross-section, while at the exit Yes, the flow from the mixing chamber, the outlet channel is blocked by a plate connected with the partition, and the inclined opening of the watering wall is directed towards the partition of the outlet channel.

In addition, the housing in the form of a chamber is equipped with an air tube, one end of which is passed through the housing cover, and the other is in communication with the atmosphere with a control valve.

The implementation of the energy absorber from the interconnected elements contributes to the quenching of the water flow due to the presence of a mixing chamber of square cross-section, accompanied by intensive mixing of water with air and the movement of water, when leaving the outlet in front of the partition in the second section, with intensive impact of the jets there is an effective residual quenching of excess kinetic water flow energy; reduces the dimensions of the fastening channel of the outlet channel in the entire range of expenses.

In FIG. 1 shows an extinguisher of energy of a water stream, plan; in FIG. 2 is a section AA in FIG. one.

The energy absorber of the water stream includes an inlet conduit 1, pressure pipelines 2 provided with swirling devices 3 that divide the stream into jets. Pipelines 2 are connected by output sections 4 built into the sealed housing 5 in the form of a camera towards each other. Under the housing 5 is a mixing chamber 6 of a square cross section. The wall 7 of the chamber 8 has a concave discharge face 8, made with the upward and toward the outlet sections 4. The side wall 7 of the chamber 6 has an inclined hole 9 connecting the chamber 6 with the outlet channel 10 and directed towards the partition 11.

An opening for the air pipe 13 having a valve 14 is made in the cover 12 of the housing 5. The lower end of the air pipe 13 is installed at the inlet of the housing 5, and the second end is connected to the atmosphere or to a compressor that delivers air through the valve 14, which affects the water flow . The mixing chamber 6 with a square cross section is located below the pressure pipes 2 and is connected through the outlet 15 to the discharge channel 10. At the outlet of the flow from the mixing chamber 6, the discharge channel 10 is blocked by a plate 16 connected to the partition 11. The partition 11 is designed to change the direction of the flow from the outlet 15 of the mixing chamber 6 into the outlet channel 10, where the stream of the jet from the inclined hole 9 is connected to one common stream, which reduces bottom velocity behind the partition 11.

The energy absorber of the water stream operates as follows. The water flow, passing through the swirling devices 3, is twisted in different directions in the housing 5. As a result of splitting the stream into jets and their collision, as well as the falling of the stream on the concave face 8, a rotational movement is formed inside the mixing chamber 6 of square cross section, part of which passes through the outlet 15, and the other part of the flow through the inclined opening 9, into the outlet channel 10 towards the partition 11 with the floor slab 16. Here the flows interact again, combine, and the resulting flow arrives t in a calm state into the outlet channel 10. With this position, the partition 11 with the floor slab 16 of the energy quenching device of the water flow is even more efficient, since there is an additional drop in the flow velocity, resulting in an intense quenching of its energy. Depending on the volume of incoming water, the pressure in the mixing chamber 6, the outflow into the outlet channel 10 to the partition 11 can be carried out either from an inclined hole 9 arranged in the wall 7 with a concave face 8 at low flow rates, or together through the outlet 15, formed by the wall of the housing 5 and the wall 7 of the mixing chamber 6 - at higher flow rates. Thus, in front of the partition 11 with the slab 16, flooding of the hydraulic jump takes place, water flows into the open exhaust channel 10. With the open valve 14, air enters through the pipe 13 into the sealed housing 5, is intensively mixed with water, carried away in a rotational movement in the mixing chamber 6 , which improves the quenching of the energy of the water flow, and passes into the area with a partition 11 with a floor slab 16 and then into the outlet channel 10. It should be clarified that for effective exposure to air flow when mixed with water, it is possible that the speed of the outlet 5 from the opening in the cover 12 of the housing 5 is not less than the flow rate in the pipelines 2, which will also depend on the filling of the housing 5 and the chamber 6 itself with a square cross section with a rotational movement of water closer to the center of the chamber, where the flow acquires compressed cross section. The higher the efficiency, the less the mass energy density of the pulsations of the flow velocities from the side of the partition 11 with the floor slab 16 acquires. Reducing the loads and shifting them to the region of final quenching of kinetic energy makes it possible to significantly protect the open discharge channel from erosion in the immediate vicinity of the quenching chamber. Due to the suppression of pulsations, the dynamic loads on the structure are not as high as in cases when the quenching is carried out only by twisting devices, and also will allow to extinguish the excess kinetic energy of the stream over a smaller length of the discharge channel. The use of air contributes to the saturation of water with oxygen, which favorably affects the development of various fauna in watercourses. When the gate valve 14 is closed, the air dissolved in the water is also discharged from the mixing chamber 6 into the discharge open channel 10, which increases the flow rate of the water passing in the water flow damper.

Thus, in three sections: intense collision, helical motion and hopping conjugation of jets, the excess kinetic energy of the flow is effectively quenched for the diverting open channel.

The proposed device can be used to extinguish the energy of a water stream in various hydraulic structures. Especially effective is the use of highly kinetic flow devices in structures. This preserves the dimensions of the fastening channel of the outlet channel and reduces the construction depth of the mixing chamber in the entire range of discharge costs. A feature of the present invention lies in the fact that increasing the efficiency and reliability of quenching the kinetic energy of the shared stream and reconnected occurs in the chamber, the shape of which is made with a square cross-section with the subsequent direction of the parts of the connecting stream towards the partition with the floor slab, i.e. under the partition, and thereby achieved a high degree of protection of the outlet conduit from dynamic influences due to the exit of air clusters in the downstream, and therefore, the reliability of the energy damper of the water stream increases; the length of the closed section of the discharge channel is reduced and the need for a well in the lower channel of the channel is eliminated.

Claims (2)

1. A water flow energy absorber, including a water conduit, pressure pipelines provided with swirling devices and connected to a closed casing in the form of a chamber facing each other, a mixing chamber is located under the casing, the wall of which has an outlet, the watery wall of the mixing chamber has a concave face on the outlet side holes in which an inclined hole is made, characterized in that the mixing chamber is made of square cross-section, while at the outlet of the stream from the mixer hydrochloric chamber exhaust channel blocked plate associated with a partition, and an inclined hole stilling wall directed toward the partition exhaust channel. 2. The damper according to claim 1, characterized in that the housing in the form of a chamber is equipped with an air tube, one end of which is passed through the housing cover, and the other is in communication with the atmosphere and has a control valve.

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