Resistance Effect of Vegetation Bending Form to Water Flow
The resistance characteristics of vegetated ecological channel is one of the research focuses of environmental hydraulics.In order to explore the resistance characteristics of flexible vegetation under different bending angles,cylindri-cal aluminum rods were bent to simulate flexible vegetation.A force measuring device was used to carry out indoor flume experiments on cylindrical aluminum rods under different inclination angles and velocity range.Firstly,the relationship between the resistance and velocity of vertical cylindrical aluminum rods was studied,and the obtained dragging force co-efficient Cd was consistent with previous studies.At the same time,the reliability of the force measuring device was veri-fied.Then,experiments on vegetation resistance under different inclination angles were carried out,and it was found that the Vogel number gradually decreased with the decrease of inclination angle and finally increased abruptly.When the veg-etation is bent,the existing rigid upright vegetation cluster model is no longer applicable.In this paper,parameters Cθ re-lated to the inclination angle are introduced to modify the model,which significantly improves the simulation accuracy.The research results can provide technical for accurate simulation of ecological vegetated river hydraulics.
NETL
NSTL
万方数据
维普
