Bed Shapes and Flow Resistance

This lecture covers the influence of bed shapes on flow resistance in rivers, focusing on the characteristics of different forms such as dunes, ripples, and benches. It explains the concept of relative traction force and the critical values of friction tension. The lecture also delves into the dimensionless variables used to describe bi-phasic flow and the Shields diagram for sediment transport. Additionally, it discusses the impact of background shapes on flow dynamics, the formation of vortices, and the geometric features of various bed forms. The instructor emphasizes the relationship between water level and flow, the determination of resistance coefficients, and the effects of background shapes on flow patterns.