Study On Hydraulic Aracteristics Of Ecological Fishway

Ecological fishway, which can not only linkup the fishing migration route, but alsoplay a role of ecological corridor to maintain the river continuum, is an importanteco-compensation measure. Therefore, the construction and research on ecologicalfishway is very important.This paper has concluded the types, construction situation, research progress onfishway, and has used the hydraulic model test and numerical simulation technology tostudy the hydraulic characteristics of4types ecological fishway which against thebackground of a project in upper Yangtze River. We focus on the effects of dischargechange, pool room structure change(the change of middle piers) and slope change onhydraulic characteristics.This paper uses hydraulic model test on type1to study the hydraulic characteristics.We has systematically measured the velocity distribution and water fall of adjacent poolsof3kinds discharge. At the same time, the business software——fluent is applied tocarry out a series of3-d numerical simulation on4types of ecological fishway. Wecompare the calculated data with the data of the physical model test, and analyze the flowregime, velocity distribution and turbulent kinetic energy distribution on four differentconfigurations. And through comparative analysis, the dimensionless velocitydistribution and attenuation of maximum velocity on cross section along the flow arestudied. The result show are as follows：Numerical simulation and experimental resultsare very close, and numerical simulation has higher calculation accuracy; The numericalsimulation is very close to the experimental results which has a high calculation accuracy②Velocity increases with the increase of flow rate, and when the downstream waterdepth is fixed, the upstream water depth is also increased;③The arrangement of middlepiers made it possible to attenuate the maximum velocity in the abutment piers, and thereduction effect of middle piers is stronger than the abutment ones; The two are reducedrespectively about30%~30%,30%~33%;④Within a certain extent(2%), the slopechange has a little influence on velocity distribution, namely the flow in the pool roomhas obvious characteristics of two-dimensional flow;⑤Through analyzing thedimensionless date of the turbulent kinetic energy on the room surface and the volumetricenergy dissipation, we find that the two have a positive correlation relationship. At last,we analyze the anvanteages and disadvantages of the4types ecologicalfishway and put forward the research prospect on fishway construction in the new era.