摘要
为探究不同底坡对渠道糙率的影响,采用9种不同底坡的人工渠道,在6种不同的流量条件下研究糙率随底坡和流量变化的规律。试验结果表明:在明渠均匀流条件下,随着底坡的变化,渠道糙率存在3种不同的变化规律。当Fr<1时,随着流量的增大,糙率逐渐减小;当1<Fr<1.51时,随着流量的增大,糙率先减小后增大;当Fr>1.51时,随着流量的增大糙率逐渐增大。当流量相同时,随着底坡的增大,糙率逐渐增大。在缓流渠道中,渠道糙率随底坡变化的速率很快;在急流渠道中,渠道糙率随底坡变化的速率较慢,糙率趋于某一常数。
In order to analyze the effect of different bottom slopes on the artificial channel roughness, an experiment is carried out under nine artificial channels of different bottom slopes with six different flow discharges to discuss the regularity of roughness changing with the bottom slope and flow discharge. The experimental results indicate that under an uniform flow, with the change of the bottom slope, channel roughness exists three different variation rules. With the increase of the flow, roughness value decreases gradually when Fr 〈 1. With the increase of the flow discharge, roughness value decreases and then increases when 1 〈 Fr 〈 1.51, and increases gradually when Fr〉 1.51. With the increase of the bottom slope, roughness value increases gradually under the same flow condition. With the change of channel bottom slope, the change rate of channel roughness is fast in the subcritical flow channel, the change rate of channel roughness is slow in the torrent channel, and rouzhness value tends to be a constant.
出处
《水利水电科技进展》
CSCD
北大核心
2013年第6期48-51,共4页
Advances in Science and Technology of Water Resources
基金
新疆水利水电工程重点学科基金(xjslgczdxk20101202)
关键词
糙率
底坡
均匀流
人工渠道
试验研究
roughness coefficient
bottom slope
uniform flow
artificial channel
experimental research
