摘要
冬季北方河流经常出现冰塞现象,而弯道处易于卡封是普遍认识,但对其形成机理的认识尚有待探索。借助于实验室的试验水槽,通过改变水流条件和冰流量条件,研究了S型弯槽和直槽冰塞形成条件,并进行对比分析,试验表明:弯槽段冰塞形成的临界Fr值大于直槽临界Fr值,即在相同水深的条件下,更大的流速时弯槽段也能形成冰塞;弯槽段能形成冰塞的Fr值范围大于直槽,故弯槽段更易形成冰塞;平衡冰塞厚度大致随着初始流速的增大而减小,随着初始水深的增大而增大,随着冰流量的增加而增加。
Ice jam is a common phenomenon for rives in cold regions.Lodgment and gorging can easily occur especially in curved channels.The formation of ice jam and its thickness distribution in curved channels were not fully understood.By changing the flow conditions and ice discharge in a flume in the laboratory,the condition of ice jam forming in a curved channel and straight flute was studied and comparatively analyzed.The experiment results showed that the threshold Fr number of ice jam forming for curved channel was larger than that for straight flute,that is to say under the condition of the same water depth,the bigger velocity of curved channel could also form ice jam.The Fr number of ice jam formation in a curved channel ranged larger than that in straight flute.The curved channel was more likely to form ice jam.Balance of ice jam thickness decreased with the increase of initial velocity,roughly increased as the initial water depth increased,and increased with the increase of the ice flow rule.
出处
《南水北调与水利科技》
CAS
CSCD
北大核心
2016年第6期87-90,共4页
South-to-North Water Transfers and Water Science & Technology
基金
国家自然科学基金资助项目(51379054)~~
关键词
冰塞
佛汝德数
临界值
平衡冰塞厚度
试验研究
ice jam
Froude number
threshold
balance thickness
experimental study
