闸墩式量水槽试验研究

Experimental Study on Pier as Water Measuring Flume

研究渠道量水设施对灌区节水、实现水资源高效可持续利用具有重要意义，在满足量水所要求的条件下，应优先选用水工建筑物量水。针对闸墩兼作量水槽并能结合闸门以实现联合测流的要求，提出一种闸墩式量水槽。选择8种收缩比和3种槽长在矩形渠道中进行了系统试验。结果表明，无量纲数Kc／Bc和H／Bc高度相关，根据理论分析和室内试验得出的流量公式简明实用，自由出流时流量计算最大相对误差3．59％。闸墩式量水槽临界淹没度可达0．91，增加量水槽长度会增大相应量水槽的临界淹没度。控制收缩比为0．49～0．65时可得到较好的量水效果。

Water-gauging facility in canals is of great significance to water saving and efficient and sustainable water utilization in irrigation districts. Hydraulic structure has priority in choosing measuring device on condition that requirements for measurement are met. To meet the combined flow measurement need of gate integrated by pier as measuring flume, pier-type flume is presented. New flume is made through a serial of experiments in rectangle canal with 8 kinds of contraction ratios and 3 kinds of lengths. The results show that non-dimension number Kc/Bc and H/Bc have highly correlation. According to theoretical analysis and experiment indoor, the simple and practical flow formula is gained in this paper. The maximum relative error of discharge calculation is only 3. 59% in free outflow. The maximum critical submergence degree of flume is 0. 91. In addition, increment in length of flume will enlarge critical submergence degree. Furthermore, better water measuring performances will be obtained if contraction ratios are controlled ran ging from 0.49 to 0.65.