挑流水垫塘坎尾壅水特性研究

挑流水垫塘(消力池)尾坎的壅水特性,对尾坎选型有重要的影响。通过模型试验实测和堰流计算的对比分析,对非淹没和淹没过流状态下尾坎壅水特性进行了研究。研究发现,受水垫塘(消力池)内的水流紊动影响,一般实际工程中尾坎高度可能偏小,因此,选择尾坎高度时需要在堰流计算的基础上适当加高。非淹没过流状态下,当泄洪流量相对较小时,尾坎高度可直接由堰流计算壅水曲线确定;随着泄洪流量的增加,水流紊动对尾坎壅水高度的影响也越来越大,尾坎的实际壅水高度与堰流计算值之间的差值逐渐增大,最高可达16.64%。淹没过流状态下,随泄洪流量的增加,水流紊动对尾坎壅水高度的影响越来越小,尾坎的实际壅水高度与堰流计算值之间的差值也逐渐减小,最小仅为7.43%。

Backwater Characteristics of Tail Bucket of Ski-jump Plunge Pool

Based on model test results and weir flow calculation results,the backwater characteristics of tail bucket of ski-jump plunge pool(stilling basin) in submerged and non-submerged state are studied.It’s found that the tail bucket height should be increased on the basis of weir flow calculation because it is smaller in actual projects influenced by flow turbulence in the plunge pool.The tail bucket height can be determined by backwater curve when the flood discharge is relatively small in non-submerged state.With the increase of flood discharge,the backwater height is increasingly subject to the influence of flow turbulence,giving rise to a greater difference between the actual backwater height and the weir flow calculation result,which could reach 16.64% at the maximum.In submerged state,the backwater height is less influenced by flow turbulence,so that the difference between the actual backwater height and the weir flow calculation becomes smaller,with 7.43% at the minimum.