从二相流方程出发研究平衡输沙──扩散理论和泥沙扩散系数的讨论

A study of sediment transport from the equations of turbulent two-phase flows──A discussion on diffusion theory and diffusion coefficient of sediment

根据力平衡原理研究泥沙浓度的垂向分布，参照湍流混合气体运动中组元间作用力的本构式的构成，给出了湍流二相流相间阻力的本构式，并由此推导了充分发展的明渠流动中泥沙浓度的垂向分布．以本文给出的泥沙力平衡方程为基础，引入某些近似可推导出沿用至今的（泥沙运动的）扩散理论所给出的方程．

The vertical distribution of sediment concentration is studied based on the force equilibrium principle in the present research. The constitutive relations of the interphase drag in a turbulent two-phase flow are given, refereing to the constitutive relations of the force between species in a turbulent gas-mixture flow. Finally the equation for the vertical distribution of sediment concentration in a fully developed channel flow is obtained. Based on the obtained equation, the diffusion equation of sediment currently used can be derived if some assumptions are introduced.