动床阻力研究与应用

Research on movable bed resistance and its application

动床阻力随床面形态的变化而变化,而床面形态又是水流强度的函数,Simons将两者关系分为三个流区,即低水流区、过渡区和高水流区。不同流区阻力特性和规律是不相同的,正确和合理地判别流区是正确确定阻力关系的先决条件。此文在Browline研究的基础上,进一步分析了影响床面形态的基本要素,提出了在第一时间判别流区的方法,建立了各区阻力关系式,并利用长江和黄河实测资料和水槽试验资料进行了预报计算,其精度优于其它同类公式。

Movable bed resistance is changed with the changes of bed surface morphology,and bed surface morphology is the function of flow intensity.Simons divided flow region into three regions which are low flow region,transition flow region and high flow region.The resistance character and law at the disparate flow region are different,so that the precondition of understanding deeply the resistance is distinguish the flow regions correctly and reasonably.On the base of Brownlie＇s research,which analyzed the basic influencing factors of bed surface morphology further,a technique to distinguish flow regions was put forward firstly,and then resistance relations for the three flow region were established.Finally,the forecast calculation for the established relations with the measured data of Yangtze River and Yellow River and of the experimental flume was carried out.The results showed that the relations have good accuracy,and they are better than other formulas.