GG282 Lecture Notes - Lecture 11: Manning Formula, Turbulence, Flow Velocity
Document Summary
Estimated using a flow formula such as the: Examine the impact of r on stream velocity using the manning equation. Width, depth, gradient and bed materials will change, thus velocity and flow conditions will vary. Water molecules move in parallel paths that slide over one another with little mixing. Water molecules move along highly variable paths with considerable mixing. Used to define the transition from laminar to turbulent flow: R= is length (distance) v(second v)= kinematic viscosity (measure of the resistance of a fluid to deform) Where v is velocity, d is depth, g is acceleration due to gravity (m/s2) When fr>1: flow is more chaotic and erosive. Velocity profiles for smooth turbulent (a) and rough turbulent flow (b) in the boundary layer. The boundary layer extends from the bed upward to the main flow. In the case of smooth turbulent flow (a) there is a thin layer of very low velocity water at the bed (labelled viscous sublayer)
