植被群落作用下河道水流紊动能分布

Distribution of Turbulent Energy in Open Channel with Vegetation Patch

植被广泛存在于自然河道中,对河流水流特性产生一定影响。利用交错排列的竹签模拟非淹没的刚性植被群落,通过水槽试验,探讨了单个植被群落对水流紊动能分布的影响。结果表明:纵向、横向和垂向三个方向的紊动能分布受到植被群落不同程度的影响,尤其是纵向上紊动能分布在植被群落下游变化较大,呈现两个峰值;植被群落下游靠近植被群落处,横向上紊动能分布为水槽中心附近最大,向两侧逐渐减小,在水槽中心紊动能沿垂向均显著增加。

Vegetation widely exists in natural rivers,and it will influence the flow characteristics on a certain degree.The bamboo skewers were chosen to simulate non-submerged rigid vegetation patches.This paper uses laboratory experiments to study the distribution of turbulent kinetic energy with a circular patch.The results show that the longitudinal,transverse and vertical distributions of turbulent energy are influenced by the vegetation patch.The longitudinal distribution behind the vegetation patch changes greatly,and it appears two peaks.In the transverse direction,the distribution of the turbulent energy gets the maximum value near the center of the channel.The turbulent energy in the centerline increases significantly.