T型分流/汇流连接井“品”字型墙均流防涡技术

Water Diversion and Vortex Precaution Technique of "∴"-type Walls in a T-junction Chamber

王庆坨连接井是一个T型分流/汇流水工建筑物,是联接南水北调中线天津段干线工程与王庆坨水库的重要枢纽。现通过实体模型试验,利用三维超声波流速仪量测不同水力条件下连接井内的流速分布,提出了在连接井内设置品字型墙均流防涡装置的新技术。"品"字型均流防涡装置结构特点为:在连接井出口闸两导墙延长线及连接井中轴线上平行布置三排导流墙,形成"品"字型导流结构,通过调节三个导流墙的相对位置,达到使下游多孔箱涵分流均匀,且防止连接井内形成较大立轴漩涡带气进入下游箱涵。"品"字型墙均流防涡装置:结构简单,施工方便,投资少,运行维护费用低,可推广到类似的横向进水、分水工程中。

The Wangqingtuo junction chamber, a T type hydraulic structure with a lateral inflow or outflow at 90°angle, is a hinge of Tianjin main line of South-to-North Water Diversion Project with Wangqingtuo reservoir. Different depth measurements were made using a point gauge while velocity measurements were taken using an acoustic doppler velocimeter over a grid defined throughout the junction region in physical model test. The water diversion and vortex precaution device of “∴”- type diversion walls was developed. The main characters of this new device were that three diversion walls were parallel arranged with one in the middle and the other two in the extended line of the separation walls in the junction chamber. It was found that the velocity downstream was well distributed and the vertical-axls vortex in front of the outlet gate was prevented by adjusting the relative positions of the three rows of diversion wall. Such new device with simply structure, easy construction and low cost can be extended to other similar lateral inflow or outflow projects.