高拱坝水垫塘体型设计优化方案试验

Test Study on Plunge Pool Shape Optimization of High Arch Dam

通过整体水工模型试验,以流态和动水压力为指标,对某高拱坝水垫塘体型的合理性进行了论证。结果表明,射流水舌在水垫塘内落点集中,加之水垫厚度不足,底板局部冲击压力和脉动压力过大;水垫塘长度不足,水流在塘内无法形成完整水跃,直接冲击翻越二道坝。为此,提出水垫塘体型优化方案,优化后水垫塘内流态明显改善,底板动水压力显著降低且分布均匀,可见优化后的水垫塘体型趋于合理,可直接指导工程设计。

Based on the factors such as flow pattern and hydrodynamic pressure, the shape design rationality and optimization of the plunge pool of one high arch dam were conducted through the whole hydraulic engineering mode[ test. It was found that the landing area of jet flow was much concentrated and then the impact force and pulsation pressure on part base plate were very large in addition of the shortness of the pool depth. Because of the lack of the plunge pool length, the complete hydraulic jump can not be formed in the pool and the jet flow impacted and boosted over the subsidiary dam. Thus, the optimized design of the plunge pool was presented to solve the existed problems. After optimization, the flow pattern in the pool was obviously improved, and the hydrodynamic pressure on the base plate decreased sharply and was well-distributed. Therefore, the plunge pool shape became rational after optimization, which could be directly used for the project design.