植物坝覆盖区明渠二维两相流场紊动特性研究

漂浮植被占用了行洪断面面积,增大了河流的阻力,遇到障物后,造成河道严重堵塞。通过室内物理模型试验和数值模拟的方法,研究、分析大面积覆盖水面的漂浮植被对河道泄洪能力、河道水体结构、水流特性的影响。根据紊动强度和雷诺应力沿程变化,从波动幅度上看,植物覆盖区波动幅度较大;对根茎区,无植物覆盖但受影响区紊动强度不大,但较无植物覆盖时的明渠水流有明显增大,植物坝覆盖区及植物坝前缘区变化显著,尤其是植物坝前缘区的紊动强度波动很剧烈。

Research on Turbulent Properties of Two-dimensional and Two-phase Flow Field of Open Channel in Vegetation Coverage Area

The floating vegetation would take up part of the cross section area for flood flow,increase flow resistance,and cause river blockage when encountering barrier.Through model test and numerical simulation,the effects of large-area floating vegetation on river flood capacity as well as on river water body structure and water flow properties are researched and analyzed.According to the streamwise variation of turbulent intensity and Reynolds stress,and based on the motion range,the motion range of vegetation coverage area is bigger;To the root-stock area,there has no vegetation coverage,the turbulent intensity in the influence area is not great,but it increases obviously compared with that in the open-chaanel flow.The variations in the vegetation coverage area and its fore-area are obvious,particularly in its fore-area,the motion of the turbulent intensity is very violent.