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SED2D-WES Version 4.3 Beta

which is applicable to the lower 15 percent of the boundary layer when

u* D

> 30

(7)

ν

where

u = mean flow velocity

D = water depth

b.

The Manning shear stress equation,

=

*

(8)

where

g = acceleration due to gravity

n = Mannings roughness value

CME = coefficient of l.0 for metric units and l.486 for English units

c.

A Jonsson - type equation for surface shear stress (plane beds) caused by waves and currents,

1 f w uom + fcu

u

u + om

u* =

(9)

2 uom + u

2

where

fw = shear stress coefficient for waves

uom = maximum orbital velocity of waves

fc = shear stress coefficient for currents

d.

A Bijker - type equation for total shear stress caused by waves and currents,

10