导流洞改建为跌流式竖井溢洪道的试验研究

结合某水电站导流洞改建永久性溢洪道试验,研究了跌流式竖井溢洪道的水力特性,并对消力井布置进行了优化研究。研究表明,该溢洪道自环形进水口以下采用突扩方式与竖井连接所形成的脱壁水流结构,与传统的贴壁式竖井的水流结构具有明显不同,不仅可以有效避免竖井段因水流流速较高可能造成的空化空蚀破坏,降低施工难度,而且有利于水舌掺气并促进消力井消能。该研究提出的消力井优化布置体型,与传统的布置形式相比具有更高的消能效率,消能效率可以达到83%以上。

Experimental study of drop shaft spillway reconstructed by diversion tunnel

Combined with an experiment on reconstruction of the diversion tunnel as a permanent spillway in one hydropower project,the hydraulic characteristics of the drop shaft spillway were studied.The optimization of the layout of the stilling well was also studied.The results show that the sudden enlargement between the circular inlet and the shaft in this spillway is significantly different from the traditional face-stuck shaft.This can prevent cavitation of the vertical shaft by high-velocity flow,reducing the difficulty of construction.It is beneficial to the water jets aeration and promotes tenergy dissipation.The optimal layout of the constructed spillway has a higher energy consumption efficiency,reaching 83%.