感潮河段底床阻力特性分析

Analysis on the riverbed resistance characteristic of tidal river

为更好地了解长江感潮河段的底床阻力特性,在实测资料的基础上,结合流速对数分布的假设及谢才公式和曼宁公式给出了适合长江梅子洲河段(感潮河段)糙率的计算公式,并将公式加入到二维有限元水动力数学模型HSCTM中。数值计算的水位、流速及流场均显示了糙率公式的合理性;从尼库拉兹实验出发结合希夫林松的阻力公式从理论上探讨了摩阻流速和糙率高度之间的关系,并采用长江感潮河段的实测资料印证了两者之间存在间接的线性关系。

In order to understand the riverbed resistance characteristic of tidal rivers more clearly, on the basis of measured data combined with the assumption that the velocity distribution is logarithmic, the Chezy formula and the Manning formula, the formula for calculating the roughness of the Yangtze River （ tidal river）, are provided. The formula has also been added to the twodimensional finite element formula of the hydrodynamic mathematical model HSCTM. The numerical results, including the water level, velocity and flow field, show that the formula for calculating the roughaess is reasonable. The relationship between shear velocity and mug）mess height is discussed theoretically with the Nikm-adsc experiment combined with the resistance formula. The indirectly linear relationship between shear velocity and roughness height is proven with the measured tidal river data from the Yangtze River.