Experiment And Numerical Simulation Model Of The Shihmen Reservoir Spillway Tunnel Hydraulic Characteristics

In the construction of Dam Project, the discharge structures often encountered inadequate flow capacity, atomization and downstream energy dissipation and other hydraulic problem. It means to solve the problem is usually physical model tests, or by numerical simulation. There is a physical model test time-consuming, not continuous information flow field flow field vulnerable to interference and disadvantages of scale effect, etc., but more intuitive model tests, the results of high confidence. Numerical simulation method can overcome the shortcomings of a scale model and flow field disturbance test exists to provide richer information on water flow in engineering practice, but there may be numerical simulation calculation error, the value of different treatment methods may lead to false results. Taking Hanzhong City, Shaanxi Province Shihmen Reservoir left bank spillway tunnel for the study,using experimental and numerical simulation model combining method, the hydraulic pressure problem exists spillway tunnel were analyzed. Main achieved the following findings:Firstly, Low water level, the cave for the next full flow alternately coexist transition flow regime; found that there is a negative pressure zone upstream of the spillway tunnel segment by turning left bank of the Shihmen Reservoir spillway tunnel gate full model analysis of test results. Bureau gate opening test results showed that: swerve pressure decreases with increasing degree of opening of the gate of the reservoir water level is gradually increased.Bucket model tests found downstream water splashing, water erosion and aerosolization a more serious problem.Secondly, For downstream atomization, erosion problems, has been tested Model Test and Analysis of the bucket with four kinds of modification of the bucket, preferably a final recommendation bucket shape, namely lob angle of + 6° bucket list side stick legs body Programme. Test test found that the atomization recommend bucket shape and erosion problems have been significantly improved.Thirdly, Section for turning out full flow and negative pressure alternately problem using FLUENT software Spillway Tunnel under different gate opening and different conditions for water level flow pattern and hydraulic parameter associated numerical simulation, analysis of simulation results obtained Hydrodynamic pressure and turning out the distribution of theflow segment plate pressure, the water line.Forthly, Test and numerical simulation model results were compared, the results show that the model tests and numerical results agree well with the overall trend, the pressure within 0.4m of the basic error, a method of numerical model and a reasonable choice for engineering practice to provide some guidance.