Formulas for the velocity distribution over a sediment bed

The logarithmic formulas for smooth flow, transitional flow, and fully rough flow, may be combined in the form:

u/u_* = (1/k)ln(y/ak_s) + 8.5 = (2.3/k)log₁₀(y/ak_s) + 8.5

where u is the average point velocity at a distance y above the bed, u_* the shear velocity, k the von Kármán “constant”, k_s a length parameter, and a a correction factor, with a value that depends on the ratio of the height of the irregularities projecting from the bed surface to the thickness of the laminar sublayer.

Back.

Back to my front page.