A structure for breaking through a threshold sand barrier based on self-vibration effect and a method for using the same

Abstract

The application discloses a kind of based on self-vibration effect's breaking down gate sand diversion wall structure, the branch stream side of dry flow and branch stream confluence has gate sand area, along the transverse extension of branch stream is used to guide water wall of high water level, guide water wall is set in gate sand area upstream;The middle part of guide water wall is equipped with gate, gate is installed in gate, and the guide water wall of gate extends downstream direction and is equipped with water retaining wall, water retaining wall extends into gate sand area, and water retaining wall includes left side wall and right side wall that are symmetrically arranged, left side wall and right side wall are all ladder-shaped, and the left side wall and right side wall are surrounded to be used to flush sand harmonic cavity for water retaining and flushing, and the downstream of flush sand harmonic cavity is narrower than upstream.The application also discloses corresponding use method.The application utilizes the structure of the application when breaking down gate sand, forms as intense resonance phenomenon as possible by artificial control height difference, and the breaking down efficiency and effect of gate sand are improved by corresponding water flow phenomenon.

Description

Structure and Application Method of Sand-Diverting Wall for Removing Barriers Based on Self-Vibration Effect Technical Field

[0001] This invention relates to the field of water conservancy engineering technology, and in particular to sand-blocking technology. Background Technology

[0002] In the confluence area of ​​main streams and tributaries of reservoirs in sandy rivers, sand barriers are easily formed at the tributary inlets, which hinder the connection between the main streams and tributaries and affect the normal functioning of the reservoir.

[0003] Sediment transport is one of the most important hydrological phenomena in rivers, significantly impacting their evolution. The confluence of tributaries and main streams in sediment-laden rivers is one of the areas where the interaction between water flow, sediment, and riverbed is most intense. Sediment easily accumulates here, commonly known as "reservoir barrier sand." Reservoir barrier sand obstructs the connection between tributaries and the main stream, exacerbating sediment deposition, raising water levels, increasing the risk of tributary floods, raising the erosion baseline, reducing the effective storage capacity of the reservoir, and weakening its regulatory capacity.

[0004] In existing technologies, there are techniques that involve setting up guide walls to concentrate the scouring force of river water to achieve water-binding scouring and thus destroy the barrier sand and effectively guide the main stream and tributaries. However, the guide walls in this technology are straight walls, which can only enhance the water flow at the guide wall due to the water-binding effect. They do not have the function of strengthening the scouring effect on the barrier sand through the self-vibration of the water body, and cannot further enhance the efficiency and effect of scouring the barrier sand to guide the main stream and tributaries. Summary of the Invention

[0005] The purpose of this invention is to provide a barrier sand guide wall structure based on the self-vibration effect, which provides a structural basis for the water flow self-vibration formed during water jet scouring.

[0006] To achieve the above objectives, this invention discloses a guide wall structure for breaking up barrier sand based on the self-vibration effect. A barrier sand area exists on one side of the tributary at the confluence of the main stream and the tributary. A guide wall extends laterally along the tributary to raise the water level, and is located upstream of the barrier sand area. A gate is provided in the middle of the guide wall, and a gate is installed at the gate.

[0007] The guide wall at the gate extends downstream and is equipped with a water-binding wall that extends into the sand-blocking area. The water-binding wall includes a left wall and a right wall that are symmetrically arranged. Both the left and right walls are stepped. The left and right walls form a sand-flushing resonant cavity for flushing sand. The downstream of the sand-flushing resonant cavity is narrower than the upstream.

[0008] The tributary water level is X meters higher than the main stream water level. The natural frequency of the sand-flushing resonant cavity matches the frequency of the water flow formed in the sand-flushing resonant cavity by the X-meter height difference.

[0009] This invention also discloses a method for using the above-mentioned barrier sand diversion wall structure based on the self-vibration effect, which is carried out according to the following steps:

[0010] The first step is installation; when the water level of the main stream is low and the tributary barrier sand is exposed above the water surface, the barrier sand-breaking guide wall structure based on the self-vibration effect is installed upstream of the barrier sand, so that the sand flushing resonant cavity extends into the barrier sand.

[0011] The second step is to regulate the water level difference by storing water; close the gate and use the guide wall to raise the water level of the tributary upstream of the gate sand until the water level difference between the tributary and the main stream reaches X meters.

[0012] The third step is to open the sluice gates to concentrate the flow and flush away the sand;

[0013] When the water level difference between the tributary and the main stream reaches X meters, the gate is opened. The tributary water upstream of the guide wall is concentrated and flows downstream through the sand-flushing resonant cavity to flush the barrier sand. When the water flows in the sand-flushing resonant cavity, a standing wave is formed in the sand-flushing resonant cavity under the resonance effect. At the downstream outlet of the sand-flushing resonant cavity, discontinuous vortex circulation and jet phenomena are formed. The discontinuous vortex circulation causes the barrier sand to be subjected to multi-directional forces and become more loose. The jet carries the sand downstream and eventually connects the main stream and the tributary.

[0014] The present invention has the following advantages:

[0015] The sand-flushing resonant cavity with stepped sidewalls can generate strong resonance at specific water flow velocities. It can also generate obvious resonance over a wide range of water flow velocities. This vibration is generated by the interaction of water flow pressure waves and eddies, causing the water flow to vibrate naturally.

[0016] Specifically, when a stable water flow passes through the sand-flushing resonant cavity, the water generates initial pressure excitation at the stepped sections on the left and right walls (i.e., the contraction surfaces of the sand-flushing resonant cavity). The stepped sections also cause the pressure excitation to be fed back into the sand-flushing resonant cavity, forming feedback pressure oscillations, which cause the water flow to vibrate naturally.

[0017] After resonance occurs, a large-scale discontinuous vortex circulation and a high-intensity jet are naturally generated at the outlet of the sand flushing resonant cavity, thereby improving the water flow's ability to flush and remove sand, achieving a better removal effect on the downstream blocking sand, and more quickly and reliably connecting the main stream and tributaries.

[0018] The natural frequency of the flushing resonant cavity matches the frequency of the water flow formed in the flushing resonant cavity by the water flow with an elevation difference of X meters. The elevation difference between the main stream and the tributary can be controlled by the timing of the gate opening to form the strongest possible resonance in the flushing resonant cavity, thereby maximizing the efficiency and effect of water jet flushing to break up the barrier sand.

[0019] By using the method of this invention, the water flow passing through the sand flushing resonant cavity is made to resonate with the sand flushing resonant cavity by controlling the water level difference. The sand blocking the gate in the downstream direction is more easily loosened by the multi-directional force under the action of the intermittent vortex circulation (normal water flow is in the downstream direction, and the turbulence formed by the impact has a small influence, so the effect of loosening the sand blocking the gate is not obvious). The jet phenomenon has a strong sand carrying capacity, and can carry more sand downstream than the same amount of water flow.

[0020] In summary, by using the method of this invention, the structure of this invention can be used to create the strongest possible resonance phenomenon when breaking up barrier sand by artificially guiding (controlling the height difference), thereby improving the efficiency and effect of breaking up barrier sand through the corresponding water flow phenomenon. Attached Figure Description

[0021] Figure 1 is a schematic diagram of the structure of the present invention.

[0022] Figure 2 shows the simulation effect of water jet flushing when there is only a water jet wall without stepped sections.

[0023] Figure 3 is a simulation diagram of the effect of water jet flushing of sand using the self-vibration effect-based sand-repelling guide wall structure of the present invention. Detailed Implementation

[0024] As shown in Figure 1, this invention provides a diversion wall structure for breaking through the barrier sand based on the self-vibration effect. The tributary 3 at the confluence of the main stream 2 (such as the Yellow River) and the tributary 3 has a barrier sand area 1 on one side. A diversion wall 4 extends laterally along the tributary 3 to raise the water level. The diversion wall 4 is located upstream of the barrier sand area 1. A gate 5 is provided in the middle of the diversion wall 4, and a gate (the gate is a conventional technology and is not shown in the figure) is installed at the gate 5.

[0025] A water-guiding wall 4 at gate 5 extends downstream and is equipped with a water-binding wall. The water-binding wall extends into the sand-blocking area 1. The water-binding wall includes a left wall 6 and a right wall 7 symmetrically arranged on the left and right sides. Both the left wall 6 and the right wall 7 are stepped (and have corresponding stepped parts 9). The left wall 6 and the right wall 7 form a sand-flushing resonant cavity 8 for flushing sand. The downstream of the sand-flushing resonant cavity 8 is narrower than the upstream.

[0026] The sand-flushing resonant cavity 8 with stepped sidewalls can generate a strong resonance phenomenon at a specific water flow velocity. It can also generate a significant resonance phenomenon over a wide range of water flow velocities. This vibration is generated by the interaction of the pressure wave and eddy current of the water flow, causing the water flow to vibrate naturally.

[0027] Specifically, when a stable water flow passes through the sand-flushing resonant cavity 8, the water generates initial pressure excitation at the stepped sections 9 (i.e., the contraction surfaces of the sand-flushing resonant cavity 8) on the left wall 6 and the right wall 7. The stepped sections 9 also cause the pressure excitation to be fed back into the sand-flushing resonant cavity 8, forming feedback pressure oscillation, which causes the water flow to vibrate naturally.

[0028] After resonance occurs, a large-scale discontinuous vortex circulation and a high-intensity jet are naturally generated at the outlet of the sand flushing resonant cavity 8, thereby improving the water flow's ability to flush and remove sand, achieving a better removal effect on the downstream barrier sand, and more quickly and reliably connecting the main stream 2 and the tributary 3.

[0029] Calculations show that a gate 5 width of 5-10 meters is sufficient, with 7.5 meters being the optimal width. In this embodiment, the gate 5 is 7.5 meters wide, the left side wall 6 and right side wall 7 of the guide wall are both 21 meters long, each stepped section 9 of the left side wall 6 and right side wall 7 is 1 meter wide, and each segment of the left side wall 6 and right side wall 7 separated by the stepped section 9 is 7 meters long.

[0030] The water level of tributary 3 is X meters higher than that of the main stream 2. The natural frequency of the sand-flushing resonant cavity 8 matches the frequency of the water flow formed in the sand-flushing resonant cavity 8 by the water flow with a height difference of X meters. X is a positive real number and X > 2 meters.

[0031] The natural frequency of the flushing resonant cavity 8 matches the frequency of the water flow formed in the flushing resonant cavity with a height difference of X meters. The height difference between the main stream 2 and the tributary 3 can be controlled by the timing of the gate opening to form the strongest possible resonance in the flushing resonant cavity 8, thereby maximizing the efficiency and effect of water jet flushing to break up the barrier sand.

[0032] The value of X meters and the natural frequency value of the matching sand-flushing resonant cavity 8 are matched and designed by the designer according to the specific conditions of the main stream 2 and tributary 3 (referencing historical water level data); since the guide wall 4 can raise the water level, as long as the guide wall 4 has sufficient height, the value of X can be specified by the designer. In this embodiment, X is preferably 4, that is, the water level of tributary 3 is 4 meters higher than the water level of main stream 2.

[0033] This invention also discloses a method for using the above-mentioned barrier sand diversion wall structure based on the self-vibration effect, which is carried out according to the following steps:

[0034] The first step is installation; when the water level of the main stream 2 (when there is a reservoir connected to the main stream 2, it refers to the reservoir water level) is low and the barrier sand of the tributary 3 is exposed above the water surface, the barrier sand-breaking guide wall structure based on the self-vibration effect is installed upstream of the barrier sand, so that the sand flushing resonant cavity 8 extends into the barrier sand.

[0035] The second step is to regulate the water level difference by storing water; close the gate and use the guide wall 4 to raise the water level of the tributary 3 upstream of the gate sand until the water level difference between the tributary 3 and the main stream 2 reaches X meters.

[0036] The third step is to open the sluice gates to concentrate the flow and flush away the sand;

[0037] When the difference in water level between the tributary and the main stream reaches X meters, the gate is opened. The water from the upstream tributary 3 on the guide wall is concentrated and flows downstream through the sand-flushing resonant cavity 8 to flush the barrier sand. When the water flows in the sand-flushing resonant cavity 8, a standing wave is formed in the sand-flushing resonant cavity 8 under the effect of resonance. At the downstream outlet of the sand-flushing resonant cavity 8, discontinuous vortex circulation and jet phenomena are formed. The discontinuous vortex circulation causes the barrier sand to be subjected to multi-directional forces and become more loose. The jet carries the sand downstream and eventually connects the main stream 2 and the tributary 3.

[0038] By using the method of this invention, the water flow passing through the sand flushing resonant cavity 8 is made to resonate with the sand flushing resonant cavity 8 by controlling the water level difference. The downstream barrier sand is more easily loosened by the multi-directional force under the action of the intermittent vortex circulation (normal water flow is towards the downstream direction, and the turbulence formed by the impact has a small influence, so the effect of loosening the barrier sand is not obvious). The jet phenomenon has a strong sand carrying capacity and can carry more sand downstream than the same amount of water flow.

[0039] In summary, by using the method of the present invention, a resonance phenomenon can be artificially guided to form when breaking up the barrier sand, thereby improving the efficiency and effectiveness of breaking up the barrier sand through the corresponding water flow phenomenon.

[0040] When the water level in the main stream is high, the water in the main stream can overflow the guide wall in this invention to store water in the tributaries.

[0041] As shown in Figures 2 and 3, by adopting the structure of the present invention, compared with the straight plate water jet flushing, the present invention enables the barrier sand to have a greater height drop in a wider area, that is, to flush away more barrier sand and achieve better main and tributary flow conduction effect.

[0042] The above embodiments are only used to illustrate and not limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention without departing from the spirit and scope of the present invention. Any modifications or partial substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A guide wall structure for breaking up a barrier sand dune based on the self-vibration effect, wherein a barrier sand dune area exists on one side of the tributary at the confluence of the main stream and the tributary, and a guide wall extends laterally along the tributary to raise the water level, the guide wall being located upstream of the barrier sand dune area; a gate is provided in the middle of the guide wall, and a gate is installed at the gate, characterized in that: The guide wall at the gate extends downstream and is equipped with a water-binding wall that extends into the sand-blocking area. The water-binding wall includes a left wall and a right wall that are symmetrically arranged. Both the left and right walls are stepped. The left and right walls form a sand-flushing resonant cavity for flushing sand. The downstream of the sand-flushing resonant cavity is narrower than the upstream.

2. The barrier sand diversion wall structure based on self-vibration effect according to claim 1, characterized in that: The tributary water level is X meters higher than the main stream water level. The natural frequency of the sand flushing resonator matches the frequency of the water flow formed in the sand flushing resonator by the X-meter height difference.

3. The method of using the barrier sand diversion wall structure based on the self-vibration effect as described in claim 2, characterized in that... The process is as follows: The first step is installation; when the main stream water level is low and the tributary barrier sand is exposed above the water surface, install the barrier sand-breaking guide wall structure based on the self-vibration effect upstream of the barrier sand, so that the sand-flushing resonant cavity extends into the barrier sand; the second step is water storage and elevation adjustment; close the gate and use the guide wall to raise the tributary water level upstream of the barrier sand until the elevation difference between the tributary water level and the main stream water level reaches X meters; the third step is gate opening and flow concentration for sand flushing; when the elevation difference between the tributary water level and the main stream water level reaches X meters, open the gate, and the tributary water upstream of the guide wall concentrates and flows downstream through the sand-flushing resonant cavity to flush the barrier sand. When the water flows in the sand-flushing resonant cavity, a standing wave is formed in the sand-flushing resonant cavity under the resonance effect, and discontinuous vortex circulation and jet phenomena are formed at the downstream outlet of the sand-flushing resonant cavity. The discontinuous vortex circulation makes the barrier sand subject to multi-directional forces and more loose, and the jet carries the sand downstream, eventually connecting the main stream and the tributary.

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