Numerical Investigation On Three-Dimensional Fishway Hydraulic Characteristic And Fish Passage Energetics

Spatial and temporal distribution of water resources in China is very uneven, to satisfy the demands of the rapid development of our country, people continue to build all kinds of water conservancy facilities in the river in recent years. These artificial gates, dams destroyed the original river, resulting in river ecosystem fragmentation, blocked the natural migration passage of fish and other aquatic animals and plants, rivers of biodiversity caused serious decline. Under the circumstances of vigorously promoting ecological civilization construction, the fishway is not only a hydraulic project, but also an ecological beneficial compensation project. It plays an important role in restoring the original river ecological environment and protecting the river species diversity.In this paper, based on collecting a vast amount of literature and the previous research results, making a thorough study on the hydraulic characteristics of the fishway, and a numerical simulation basic principle of the free surface flows in open channels, such as the fishway, is described in detail on the use of FLUENT software. The main contents of this thesis are listed as follows:(1) On the basis of reading and sorting extensive literature, the domestic and foreign research progress of fishway are summarized in detail. Combined with the actual engineering situation at home and abroad, putting forward our country problems in constructing fishway and discussing the application of numerical simulation in the fishway design and research.(2) It introduces the necessity of the construction of the fishway, at the same time, involved in some items, such as the fish swimming ability, the layout of the basic principles of fishway, the types of fishway characteristics, the hydraulic characteristics of different types of fishway parameters.(3) Briefly introducing the basic governing equations, numerical algorithm, turbulence model, numerical simulation method of the free surface of the fishway.(4) In this paper, through the hydraulic model test, validating the discharge capacity of Surface Orifice Spillway for a Hydropower Station. Through testing the hydraulic parameters of the Surface Orifice Spillway, and getting the reservoir water level-flow rate curve.(5) According to the test results, the CAD, ANSYS ICEM and FLUENT software was used to numerical investigation of the spillway. Comparisons between the numerical predictions and the experimental measurements have been produced, the alignment is higher. It shows that the FLUENT software can achieve high precision in simulating the flow problem with free surface flow channel.(6) Three-dimensional (3-D), computational fluid dynamics model (CFD) of ipsilateral vertical-slot fishway and opposite side vertical-slot fishway was successfully established. The velocity field characteristics of a single poud indicate a strong 3-D velocity field in the fishway, with eddies, flow separations, vortices, upwellings, and downwellings. Based on the burst swimming speeds, the simulated flow-field results are employed to calculate the force and energy acting on the adult pink salmon.The hydraulic characteristic of fishway and the quantitative analysis of fish passage energetic have a guiding significance to the fishway construction management and optimization design of structure, the modeling approach could be utilized for the further research of the fishway and management of fishways.