Figure 2. Definition sketch for terminology

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ERDC/CHL CHETN-IV-34

June 2001

If zs = ha, the total transport through the water column is obtained:

U aCb ha

[1 - exp(-λ)]

qin (ha ) =

(4)

Chart Datum

Suspended Particle

Trajectory

ha C(z)

∆z

Channel Design

qin

Cross Section

Z=0

Figure 2. Definition sketch for terminology

The advective velocity across the channel Uc can be estimated from the continuity equation

given the velocity and ambient depth upstream of the channel and the average depth hc in the

channel:

Uc =

(5)

Therefore, if a suspended sediment particle of fall speed Vf is transported with advective velocity

Uc across a channel of width W, it will fall a vertical distance ∆z given by:

hc V f

∆z =

Vf =

(6)

ha U a

Particles suspended to level ∆z or greater at the updrift end of the channel will pass over the

channel, whereas particles with elevations less than ∆z will fall into the channel and be deposited

there.

The ratio p of the total suspended transport qin that is trapped by the channel can be estimated

from: