摘要
冰盖作为冰期河流的上部约束,极大地改变了冰下水流结构。为了解冰下水流流态特征,在黄河什四份子河段开展了冰情测验,利用象限分析法对实测冰盖水流数据进行了流态分析。结果表明,各流态在各断面的出现频率基本一致;上层水体中,内向与外向交互流态对雷诺应力的贡献率之和小于喷射与下扫流态,下层水体则相反,说明上层水体主要以内向与外向交互流态为主,下层水体则主要以喷射与下扫流态为主。由于冰盖的存在,改变了水流的紊动结构,中上层水体出现逆流速梯度,改变了中上层水体的水流流态,下层水体则未受影响,冰盖对水流流速分布的影响是流态变化的根本原因。研究为冰下水流流态的认识提供了基础支撑。
As the upper constraint of rivers,the ice sheet changes the structure of water flow under ice greatly.In order to understand the characteristics of water flow under ice,the ice condition test was carried out in the Shisifenzi bend of the Yellow River,and the measured flow was analyzed by using the quadrant analysis method.The results show that the occurrence frequency of the flow regime in each section is basi⁃cally the same.In the upper layer,the sum of the contribution rates of the inward and outward interaction flow regime to the Reynolds stress is less than that of the ejection and sweep flow,however,the lower layer is the opposite.It shows that the upper layer is dominated by inward and outward interaction,while the lower layer is dominated by ejection and sweep.Due to the existence of ice sheet,the turbulence structure of wa⁃ter flow is changed,and the counter-current velocity gradient appears in the middle and upper layers,which influnces the middle and upper layers,while the lower layers are not affected.The influence of ice sheet on the flow velocity distribution is the fundamental factor for the change of flow regime.The research could provide the basic support for the understanding of water flow regime under ice.
作者
罗红春
冀鸿兰
牟献友
郜国明
张宝森
LUO Hongchun;JI Honglan;MOU Xianyou;GAO Guoming;ZHANG Baosen(College of Water Conservancy and Civil Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China;Yellow River Institute of Hydraulic Research,Zhengzhou 450000,China)
出处
《水文》
CSCD
北大核心
2022年第4期7-11,共5页
Journal of China Hydrology
基金
国家自然科学基金资助项目(51969020,52169017)
2018自治区应用技术研究与开发资金项目(201802104)
内蒙古自然科学基金重点项目(2022ZD08)。
关键词
冰盖
水流流态
象限分析法
原型试验
黄河
ice cover
water flow regime
quadrant analysis method
prototype test
Yellow River
