Mechanisms of ice accumulation in a river bend-an experimental study  

作　　者：Jun WANG Jue-yi SUI Hong-ya ZHANG Pang-pang CHEN Faye HIRSHFIELD 

机构地区：[1]School of Civil Engineering,Hefei University of Technology [2]Environmental Engineering Program,University of Northern British Columbia Prince George [3]Anhui Institute of Architectural and Industry [4]Environmental Science Program,University of Northern British Columbia Prince George

出　　处：《International Journal of Sediment Research》2012年第4期521-537,共17页国际泥沙研究（英文版）

基　　金：supported by the National Natural Science Foundation of China (50979021);the Natural Science Foundation of Anhui Province(090415217);Hefei University of Technology(GDBJ2008-020-Seed Grant for Ph.D.);Hefei University of Technology(2010HGXJ0064-Science Fund for Young Scholars);Natural Science and Engineering Research Council of Canada

摘　　要：In this study, under conditions of different flow and ice discharge, extensive experiments have been carried out in a 180°-bend flume and an S-shaped bend channel. The phenomenon and mechanisms of ice accumulation in the bend channel have been studied, lee accumulation along the convex bank was normally thicker than that along the concave bank. The maximum thickness of ice accumulation in the downstream bend channel occurred close to the convex bank. The difference between the maximum thickness and tile minimum thickness of ice accumulation was significant. The entire ice accumulation became unstable if flow Froude number was large. When the flow Froude Number is high, the entire ice accumulation becomes unstable. For Froude Number between 0.035 and 0.060, the bottom surface of＇ ice accumulation became waved in form. Small changes in Froude number and ice discharge rate can change a channel from a state of no ice accumulation to uniform accumulation over the channel bend. The higher the ice discharge, the more uniform the ice accumulation. The experimental results have been compared with field observations of ice jams at the Hequ Reach of the Yellow River.In this study, under conditions of different flow and ice discharge, extensive experiments have been carried out in a 180°-bend flume and an S-shaped bend channel. The phenomenon and mechanisms of ice accumulation in the bend channel have been studied, lee accumulation along the convex bank was normally thicker than that along the concave bank. The maximum thickness of ice accumulation in the downstream bend channel occurred close to the convex bank. The difference between the maximum thickness and tile minimum thickness of ice accumulation was significant. The entire ice accumulation became unstable if flow Froude number was large. When the flow Froude Number is high, the entire ice accumulation becomes unstable. For Froude Number between 0.035 and 0.060, the bottom surface of＇ ice accumulation became waved in form. Small changes in Froude number and ice discharge rate can change a channel from a state of no ice accumulation to uniform accumulation over the channel bend. The higher the ice discharge, the more uniform the ice accumulation. The experimental results have been compared with field observations of ice jams at the Hequ Reach of the Yellow River.

关 键 词：180° bend flume Frazil ice Ice jam or ice accumulation S-shape bend channel Thickness profile 

分 类 号：P333[天文地球—水文科学]