BackgroundVelocity distributions refer to the spatial and temporal patterns of velocity in open channel flow. Our focus this week will be restricted primarily to those distributions in a vertical water column at a particular location. We call this the velocity profile U(y) and we will discuss the difference in profiles between the viscous boundary layer and the larger turbulent portion of the flow. We will focus primarily on the so-called logarithmic velocity profile (PvK).We will then focus on models of uniform flow (no convective accelerations) and steady flow (no local accelerations). We will see how these equations are derived, what the assumptions required to employ them are and how these are commonly applied in every day practice. We will see that the derivation of uniform flow equations depends on a balance between driving forces and resisting forces and will discuss the many ways in which flow resistance influences the flow and various mechanisms for representing it. Lecture Materials
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