深孔有压隧洞平板闸门小开度闸后水力特性及 改善措施试验研究

深孔有压隧洞平板闸门小开度运行时,闸后水流侧收缩现象比较严重,流态较为复杂,需要采取一定的工程措施来改善闸后水流流态。基于物理模型试验与理论分析相结合的方法研究了不同导流坎坎高下的闸后水力特性。结果表明:闸后水流侧收缩现象随导流坎坎高的增加而减小,闸后水流水舌高度和水舌长度明显降低且底板负压基本消失,压强分布趋于均匀。但闸室导流坎坎高的增加对过流能力有一定影响,相对平底闸室,闸下过流能力随导流坎坎高的增加而减小,为避免影响过流能力,导流坎坎高不宜太大。

Experimental Study on the Hydraulic Characteristics and Improvement Measures of Deep Hole Pressurized Tunnel Plane Gate After Small Opening

The side contraction of the water behind the gates is more serious and the water flow diffuses longitudinally, resulting in a more complex flow pattern, when the plane gate of the deep-hole pressure tunnel operates with small opening. Therefore, some engineering measures need to be taken to improve the flow pattern behind the gates. Based on the physical model experiment and the theoretical analysis, the hydraulic characteristics behind the gate under different heights of diversion ridge are studied in this paper. The results show that the side contraction of the water behind the gate decreases with the increase of the height of the diversion ridge, the height and length of the tongue of the water behind the gate decrease significantly and the negative pressure of the bottom plate basically disappears, and the pressure distribution tends to be uniform. However, the increase of the height of the diversion ridge in the gate chamber has a certain influence on the flow capacity. Compared with the plane bottom gate chamber, the flow capacity under the gate decreases with the increase of the height of the diversion ridge. In order to avoid affecting the flow capacity, the height of the diversion ridge should not be too high.