确定泥沙运动有效切应力方法的探讨

On the effective shear stress of sediment transport

本文通过理论分析及实测资料检验表明 ,无论对于何种泥沙运动状态 ,决定泥沙运动的有效切应力既不是沙粒切应力又不是全部切应力 ,而是介于两者之间 ,近似为沙粒切应力与全部切应力的几何平均值 .这一有效切应力不但是对切应力类水流强度指标的总结 ,还可以概括平均流速和水流功率等水流强度指标 .

The effective shear stress of sediment transport is analyzed theoretically and tested by experimental data.The result shows that the effective shear stress is neither the overall shear stress nor the sand grain shear stress,but the geometric mean of these two stresses.The effective shear stress not only generalizes the flow intensity but also summarizes the flow intensities of mean flow velocity,stream power and unit stream power.