Flow-line variable-cross-section back-flushing energy dissipation fishway with fish luring function

Abstract

The invention provides a flow-line variable-cross-section back-flushing energy dissipation fishway with a fish luring function. The flow-line variable-cross-section back-flushing energy dissipation fishway comprises bottom plates, back-flushing water outlets, a base, flow-line-type combination side walls, back-flushing waterways, a lower chamber, an underwater water outlet; the flow-line-type combination side walls are uniformly arranged along the whole fishway; the back-flushing waterways are formed in the bottom plates and are located at downstream parts which are 60 cm away from narrowest parts of the fishways defined by the left and right flow-line-type combination side walls; the lower chamber is arranged below the bottom plates; the underwater water outlet is formed in a bottom partof a tail end of the lower chamber; and each back-flushing waterway is of a curve-surface structure of which the lower part is large and the upper part is small. The flow-line variable-cross-section back-flushing energy dissipation fishway has the beneficial effects that flowing speed and flow of bottom-layer water flows of the water outlets of the fishway are increased through bottom-layer high-pressure water flows, and a fish luring effect of the water outlets in the fishway is improved; back-flushing water flows and flow-line-type fishway side walls are designed, so that water flow energy in the fishway is dissipated; the flowing state and flowing speed of water flows in the fishway are improved; and a fish passing rate of the fishway is improved.

Description

technical field [0001] The invention belongs to the technical field of water conservancy engineering, in particular to a recoil energy-dissipating fishway with variable streamline cross-section and the function of luring fish. Background technique [0002] Migration is an active, regular, cyclical movement of some fish species that repeats annually as the stages of the fish life cycle progress; dam construction blocks fish migration, which has a negative impact on fish reproduction and river There is a relatively large potential threat to the ecology of the dam; as an important facility for migratory fish and other aquatic animals to pass through the artificial dam, the fishway plays an important role in coordinating the contradiction between the dam construction and the ecological environment. to meet the requirements of migratory fish going up or down the river; the existing fishways, including hundreds of patented technologies, mainly include simple trough type, Daniel ty...

AI Technical Summary

Problems solved by technology

[0002] Migration is an active, regular, cyclical movement of some fish species that repeats annually as the stages of the fish life cycle progress; dam construction blocks fish migration, which has a negative impact on fish reproduction and river There is a relatively large potential threat to the ecology of the dam; as an important facility for migratory fish and other aquatic animals to pass through the artificial dam, the fishway plays an important role in coordinating the contradiction between the dam construction and the ecological environment. to meet the requirements of migratory fish going up or down the river; the existing fishways, including hundreds of patented technologies, mainly include simple trough type, Daniel type, diaphragm type and different varieties of fishways, but most of them are currently The fish passing rate of the fishway is low; the hydraulic problems involved in the fishway are one of the key factors affecting the success of the fishway. For water conservancy projects with water head, the current existing technology is easy to achieve the purpose of higher fish passing rate, but for water conservancy projects with medium and high water heads, due to the current energy dissipation method used in the fishway, it is very easy to form eddy currents or turbulent flows, which may be difficult for some individuals with small , the target fish species with small ability to overcome the flow velocity and poor adaptability to complex flow regimes cannot achieve a high fish passing rate; the existing technology rarely involves the flow regime and velocity at the entrance of the fishway, resulting in The poor effect of luring fish at the exit of the fishway exacerbates the reality of the low fish passing rate in the fishway; the Chinese patent CN 205152915 U fishway replenishment and fish luring system is only used to lure fish along the fishway section, and does not take water into account. After flowing into the water, surface flow is mainly formed, and the effect of luring fish near the entrance of the fishway is poor; Chinese patent CN 106759165 A has a fishway with a constant inlet flow rate. Considering the poor effect of luring fish near the entrance of the fishway, it is trying to improve. However, the technical solution needs to be discussed. The patent adds a shaft at the entrance, and many side holes are opened on the left and right sides of the shaft. Although there are also bottom holes, this improvement will cause many problems. In the embodiment of the side hole, in these two embodiments, the water flow will still flow out from the upper part, and there is little or no water flow in the lower part; in the embodiment of the side hole in the lower layer, only the low layer flow is emphasized and the surface water flow disappears, so the improvement effect cannot be achieved; Secondly, a large number of lateral water outlet holes are used to flow out. The direction of the outflow and the direction of the water flow are perpendicular to the direction of the flow, which will lead to turbulence of the water flow, difficulty for fish to find the entrance, reduction of energy, and poor fish luring effect. Finally, because the total water volume does not change, the total water flow velocity There is no change, and the fish luring effect cannot be improved

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