水土保持学报2017，Vol.31Issue(6)：1-7,7.DOI:10.13870/j.cnki.stbcxb.2017.06.001
模拟植被地表覆盖率和粗糙度对坡面流水动力特性的影响
Effect of Simulate Vegetation Coverage and Surface Roughness on Hydrodynamics of Overland Flows
摘要
Abstract
In order to study the dynamic characteristics of overland flows under the combined effects of rigid vegetation coverage and surface roughness,the hydraulic flume experiment was carried out.The experiment included 10 discharges (0.33～1.95 m3/h),five different coverage levels (0,0.5％,1％,1.5％,2％),four different surface roughness levels (ks=0.01,0.18,0.25,0.38 mm) and one angle level (15％).The results show that:(1) The flow velocity fluctuated from 0.06 to 0.59 m/s,the average flow velocity was negatively correlated with the vegetation coverage and the surface roughness.When the vegetation coverage increased,the average flow velocity which increased with the discharge would reduce the level of increase.The correction factor (α) coefficient had a positive correlation with the vegetation coverage and a negative correlation with the surface roughness.(2) The Reynolds number ranged 153～910,the flow pattern was mainly concentrated in the transition zone and the virtual laminar zone,and the flow regime was mainly concentrated in the rapids zone.With the increases of vegetation coverage and surface roughness,the flow regime gradually extended to the slack zone (Fr＜ 1).(3) The total flow resistance coefficient was exponential with Reynolds number,and positively correlated with surface roughness and vegetation coverage.(4) The influence index of resistance showed that when the flow rate was less than 1.05 m3/h,the influence of surface roughness was greater than the vegetation coverage,otherwise the vegetation coverage became into the prominence.The total resistance was significantly different with the linear superposition value of grain resistance and surface object resistance through t-test,indicating that the linear superposition could not be used to calculate the total resistance,when the grain resistance and surface object resistance existed.关键词
坡面流/植被覆盖/地表粗糙/水力学特性Key words
overland flow/vegetation coverage/surface roughness/hydraulic property分类
农业科技引用本文复制引用
刘文剑,张会兰,王玉杰,王云琦,杨坪坪,王晨沣,赵兴龙..模拟植被地表覆盖率和粗糙度对坡面流水动力特性的影响[J].水土保持学报,2017,31(6):1-7,7.基金项目
中央高校基本科研业务费专项(2016ZCQ06) （2016ZCQ06）
