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Boundary shear stress (for natural rivers)

Description

Assuming a single, well-mixed, homogeneous fluid and a single acceleration due to gravity (both are good assumptions in natural rivers, and the second is a good assumption for processes on Earth, or any planetary body with a dominant influence on the local gravitational field), the only two variables that determine the boundary shear stress are the depth and the slope. For natural streams a typical useful relationship exists

Related formulas

Variables

τbboundary shear stress (Pa)
cunitsUnit conversion constant equal to 1 (kg/m2*s2)
hDepth of the flow (m)
sLope (dimensionless)