高水头大流量泄洪洞侧壁掺气设施水力特性研究

Study on hydraulic characteristics of sidewall aerators in high-head large-discharge spillway tunnel

本文利用模型试验方法,对高水头大流量泄洪洞高流速明流洞段边墙掺气设施的水力特性开展了系统研究。在分析侧壁掺气效果的影响因素及下游边墙水翅成因的基础上,提出了两种防水翅侧坎体型,该体型通过控制侧空腔长度沿水深方向的变化,在保证掺气效果的同时能有效抑制侧墙水翅的形成。研究还表明,设置侧壁掺气设施一般会影响底部掺气效果,应对掺气底坎和侧坎进行整体优化。最后,基于对侧坎水力特性的综合分析,提出了侧壁掺气设施体型设计原则及优化方法。

Hydraulic characteristics of sidewall aerators in high-head large-discharge spillway tunnel have been studied by adopting a model test approach in this work. We made an analysis on the factors of aeration effect and the causes of sidewall water-wings and obtained two shapes of water wing-free sidewall aerators. These new shapes have good air-entraining behaviors and an ability to inhibit the formation of water wings on the sidewall via＇controlling the length of side cavity. The results also show that generally sidewall aerators produce a certain effect on the air entrainment near the bottom, and thus the bottom aerator and side aerator should be optimized as a whole. Finally, a discussion is presented on design principles and optimization methods for sidewall aerator shapes, based on a comprehensive analysis on the hydraulic characteristics of sidewall aeration.