齿墩数量对齿墩式内消能工消能率影响试验

针对洞塞式消能工对消能体型的过流能力有较大影响的缺点,为尽可能减小其影响,进行了齿墩式内消能工物理模型试验,设计了面积收缩比为0.375条件下不同齿墩数量的3种方案来试验分析齿墩式内消能工过流能力、局部水头损失系数、消能效果、脉动压强特性及脉动流速特性。试验结果表明:齿墩数量对齿墩式内消能工的消能效果起着一定的作用,在试验范围内,随着齿墩数量的增加,过流能力增强,局部水头损失系数减小,消能率降低;紊动强度在距齿墩段进口1.5D(D为管道内径)处达到最大,7D后趋于平稳;脉动压强在距齿墩段进口1.3D~1.6D达到最大,然后急剧衰减,在距进口5.6D处趋于平稳。

Experimental study on influence of number of tooth blocks on energy dissipation efficiency of tooth block energy dissipater

In order to reduce the influence of a plug energy dissipater on the conveyance capability, a tooth block energy dissipater was investigated through physical modeling experiments. Through the testing of three schemes with different numbers of tooth blocks and the same area contraction ratio of 0.375, the conveyance capacity, local head loss coefficient, energy dissipation effect, turbulence intensity, and characteristics of fluctuating pressure were analyzed. The results show that the number of tooth blocks has a certain effect on the energy dissipation effect, and, in the experimental range, with the increase of the number of tooth blocks, the conveyance capacity increases, the local head loss coefficient decreases, and the energy dissipation efficiency declines. The maximum turbulence intensity occurs 1.5 times the tunnel diameter away from the inlet of the tooth block, and then become stable further than 7 times the tunnel diameter away. The maximum fluctuating pressure occurs 1.3 to 1.6 times the tunnel diameter away from the inlet of the tooth block, then sharply decreases, and finally become stable 5.6 times the tunnel diameter away from the inlet of the tooth block.