This study integrates a large eddy simulation (LES) model and volume of fluid (VOF) method to simulate the free-surface flows over inflexible circular-crested dams of different shapes. The simulated water depths and pressures on the dam surface are validated by the results of laboratory experiments. Then the numerical model examines the effects of the water depths and the Reynolds number on the hydrodynamic force and the discharge coefficient. The simulation results reveal that the time-averaged drag coefficient decreases as the downstream water depth H₂ increases, while the influence of water depth H₂ on the lift coefficients is less significant. Furthermore, the discharge coefficients of circular and elliptical dams, computed from the simulated velocity profiles over the crest of the dam, agree with the formulae suggested by previous studies when the downstream depth H₂/H₁ < 0.90. In contrast, the discharge coefficient of a tear-shape dam is slightly larger than those of circular dams.

中文翻译：

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橡胶坝自由面流动的数值分析

这项研究集成了大型涡流模拟（LES）模型和流体体积（VOF）方法，以模拟不同形状的非挠性圆拱坝上的自由表面流动。大坝表面的模拟水深和​​压力已通过实验室实验的结果进行了验证。然后，数值模型检验了水深和雷诺数对流体动力和排放系数的影响。仿真结果表明，该时间平均阻力系数减小作为下游水深度H _2倍的增加，而水深度H的影响₂对升力系数影响不大。此外，根据大坝顶部的模拟速度曲线计算得出的圆形和椭圆形大坝的流量系数，与下游深度H ₂ / H ₁ <0.90时先前研究所建议的公式一致。相反，泪状坝的排放系数略大于圆形坝的排放系数。