The Segment In The Discharge Flow Aeration Hom Numerical Simulation And Experimental Research

In the construction of the dam projects, the cavitations’damage of the release structures has been one of the key problems for attention. Aerator set on the surface of the outlet structures to reduce or avoid cavitations damage has been recognized as one of the most effective technical measures to alleviate cavitations. The bottom slope of the release structures often encounter anti-arc which is more complex than the straight slope segment. The study of flow characteristics of anti-arc and anti-arc aeration mechanism is meaningful.In this paper, Mainly through the establishment of two-dimensional mathematical model for numerical simulation, To study the relationship of anti-arc radius, the aerator and anti-arc flow characteristics and aeration cavity characteristics, and analyze the results of numerical simulation and model test results, used to verify the feasibility and accuracy of the numerical simulation.The numerical simulation adopt two-phase flow VOF model and RNG turbulence model to simulate anti-arc currents flow process, water tongue shape, characteristics of aeration cavity, flow distribution under different conditions. Through the establishment of the model of the anti-arc chute in experiment, in order to analyze the anti-arc aerated flow characteristics, the aerator body size influence of the aeration cavity characteristics, the experimental results and numerical calculation results at different points.this is the conclusion of this research,1) When referred to computational model with the complex boundary, use unstructured mesh computational domain, use two-phase flow VOF model and RNG turbulence model to simulate anti-arc currents flow process, the results show that, numerical simulation and experimental results are in good agreement, the numerical simulation method is feasible;2) According to the numerical simulation and experimental results, increases of anti-arc radius will cause growth of cavity length and reduction length of the cavity water.so, to increase the anti-arc radius can improve the flow cavitations characteristics.3) According to the numerical simulation, with the increase of the slope of bucket, cavity length and cavity water length becomes longer, but in the experiment, between bucket slope and slope bucket is not all positive relationship. There are some errors with the numerical simulation results; in experiment, increased traffic will cause the growth of the cavity length and cavity water length, and more obvious changes within the range of small flow;4) According to the numerical simulation and experimental results, bucket height changes have a significant impact on the flow pattern, the numerical simulation calculations show that the turbulence is strongly, as the cavity length and the length of the cavity water is proportional to the height of the bucket, there are some limitations by changing the bucket height to improve the cavity characteristics.