# Model help:DredgeSlotBW: Difference between revisions

## DredgeSlotBW

This model is a calculator for aggradation and degradation of sediment mixtures in gravel-bed streams subject to cyclic hydrographs.

## Model introduction

This program calculates the 1D bed evolution of a sand-bed river after installation of a dredge slot.

## Model parameters

Parameter Description Unit
First parameter Description parameter [Units]
Parameter Description Unit
First parameter Description parameter [Units]

## Uses ports

This will be something that the CSDMS facility will add

## Provides ports

This will be something that the CSDMS facility will add

## Main equations

• bedload calculation using Ashida-Michiue formula
 $\displaystyle{ q_{Bj} = 17 \tau _{*j} ^ \left ( {\frac{3}{2}} \right ) \left ( {\frac{1 - \tau _{*cj}}{\tau _{*j}}} \right ) \left ( 1 - \sqrt{ {\frac{\tau _{*cj}}{\tau _{*j}}}} \right ) \ast p_{j} }$ (1)
• Entrainment of suspended sediment
 $\displaystyle{ E_{si} = {\frac{B \left ( \lambda X_{i} \right ) ^5 }{1 + {\frac{B}{0.3}} \left ( \lambda X_{i} \right ) ^ 5}} }$ (2)
 $\displaystyle{ X_{i} = \left ( {\frac{u_{*sk}}{v_{si}}} R_{pi} ^ \left (0.6\right ) \right ) S_{0} ^ \left (0.08\right ) \left ( {\frac{D_{i}}{D_{50}}}\right ) ^ \left ( 0.2 \right ) }$ (3)
• Overall suppression of entrainment due to mixture effects
 $\displaystyle{ \lambda = 1 - 0.28 \delta _{\Phi} }$ (4)
• Particle Reynolds number
 $\displaystyle{ R_{pi} = {\frac{\sqrt{ R g D_{i} } D_{i}}{\nu}} }$ (5)