Simulating complex hydraulic conditions, particularly two-phase flows over spillway chutes, can be achieved with high accuracy using three-dimensional numerical models. This study investigates the potential for vacuum generation and cavitation phenomena on the Aghchai Dam service spillway through numerical simulations conducted in Flow-3D. The analysis focuses on two specific flow rates, 4400 and 1065 cubic meters per second, as determined by experimental data. The Volume of Fluid (VOF) method is employed to accurately calculate the free surface flow. Simulation results at a discharge rate of 4400 cubic meters per second indicate a high likelihood of cavitation at critical locations, including the ogee curve and the angle transition in the chute channel. These areas require specific mitigation measures to prevent cavitation-induced damage. In contrast, at the lower flow rate of 1065 cubic meters per second, the risk of cavitation is minimal due to reduced flow velocity and the absence of flow separation from the bed. The numerical findings align closely with empirical observations, demonstrating the reliability of the simulation approach in predicting cavitation behavior.

翻译：利用三维数值模型可以高精度地模拟复杂的水力条件，特别是溢洪道泄槽上的两相流。本研究通过在Flow-3D中进行的数值模拟，探讨了Aghchai坝实用溢洪道上产生真空和发生空化现象的可能性。分析基于实验数据确定的两个特定流量（4400立方米/秒和1065立方米/秒）展开。研究采用体积分数（VOF）方法来精确计算自由表面流。在4400立方米/秒的泄流量下，模拟结果表明，在关键位置（包括堰顶曲线和泄槽渠道的角度过渡段）极有可能发生空化。这些区域需要采取特定的缓解措施以防止空化破坏。相比之下，在1065立方米/秒的较低流量下，由于流速降低且水流未从床面分离，空化风险极小。数值模拟结果与经验观测高度吻合，证明了该模拟方法在预测空化行为方面的可靠性。