摘要
采用3种不同粒径粗糙度的人工加糙明渠和光滑PVC壁面明渠,在9种不同底坡、6组不同的流量条件下,研究了明渠均匀流中糙率值与粗糙度、弗汝德数间相关关系。研究结果表明:(1)相同流量条件下:随着弗汝德数Fr的增大,糙率n值逐渐增大。同一弗汝德数Fr下,粗糙度Δ越大,糙率n值越大。(2)不同绝对粗糙度下:随着弗汝德数Fr增大,糙率n值增大。当Fr<0.70时(即缓流),糙率n值与弗汝德数Fr有关,与绝对粗糙度Δ关系不大,即n=f(Fr);当0.7<Fr<1.0时(即缓流),糙率值n与弗汝德数Fr和绝对粗糙度Δ都有关系,即n=f(Fr,Δ);当Fr>1.0时(即急流),糙率n值与绝对粗糙度Δ有关,与Fr关系不大,即n=f(Δ)。
The relationships between the roughness values and roughness,Froude number of open channel flow were investigated using 3kinds of different roughness of artificial roughness channel,in 9different bottom slopes and 6groups of different flow conditions.The results showed that：（1）Under the same flow condition,with the increase of Froude number Fr,the roughness value nincreased.Under the same Froude number Fr,the greater the roughnessΔ,the greater the roughness value n.（2）Under different absolute roughness,when Fr〈0.70,the roughness value n was related with Froude number Fr,and had little relation with absolute roughnessΔ,n=f（Fr）.When 0.7〉Fr〉1.1,the roughness value nhad a relationship with the Froude number Frand absolute roughnessΔ,n=f（Fr,Δ）.When Fr〉1.1,the roughness value n was related with absolute roughnessΔ,and had little relation with Froude number Fr,n=f（Δ）.
出处
《南水北调与水利科技》
CAS
CSCD
北大核心
2016年第2期183-186,共4页
South-to-North Water Transfers and Water Science & Technology
基金
新疆维吾尔自治区自然科学基金资助项目(2015211A025)~~
关键词
粗糙度
均匀流
糙率系数
弗汝德数
roughness
uniform flow
roughness values
Froude number
