底格栅模型相似问题及优化体型水力特性研究

Similarity of Water Diversion of Grille-bottom Scales and Hydraulics Characteristics of the Optimal Style

针对山区多沙河流引水防沙问题,进行了底格栅取水的研究,得出了水力特性的试验成果。为解决因格栅尺寸较小,模型难以加工且可能因模型的缝隙过小使水流达不到阻力平方区而使模型相似率得不到保证的问题,通过系列模型试验方法对模型相似率进行了研究,表明栏栅的过流能力不受栅条和缝隙的具体尺寸的影响,而只与栅条形状有关。试验观察发现,格栅廊道水流前缘的边墙是阻水的关键部位,提出了栅条长度可缩短1/4的优化体型,仅减小1%～10%的取水流量。

The study on water diversion of grillebottom was carried out in order to solve water utilize problem in the excessive sediment mountainous river, so the test of hydraulic characteristics was carried out. A serious model test was made to study the simulation law for overcoming the difficulty of making the model's grille of very small scale, while the similarity may not be very good because of insufficient Reynolds number, which show that the discharge capacity of the grille is only related to the shape but not to its practical scale. The experiment showed that the key part of blocking water was the front wall, so the optimization style was introduced with the grille length reduced to 3/4 of the conventional style while the effect of water diversion is only reduced 1%～10%.