Numerical Simulation and Intelligent Computing of Aeration Characteristics on Step Surface of Stepped Spillway Dam

In order to explore the influence of the slope of stepped spillway dam on the aeration characteristics of stepped spillway surface under high head and large single width flow, taking a hydropower station as the prototype, RNG and VOF models were introduced to conduct numerical simulation research on the different angle of stepped spillway: 51.34 degrees, 53.13 degrees and 56.98 degrees. Results show that the length of the aerated cavity increases first and then decreases with the increase of slope. When the angle is 53.13 degrees, the length of the aerated cavity is the longest, which is 7.5m. The rule of aeration concentration of step surface is consistent with the rule of cavity length. As the slope increases, the aeration concentration of step surface increases first and then decreases. In each cavity segment, the aeration concentration of step surface is lower than 3% of the minimum protection aeration concentration of step surface, under which cavitation damage will occur on step surface.