111031 River2DM user guide.pdf

HEC River2D Morphology

© Stephen Kwan, October 2011

HEC River2DM User Guide

About River2D Morphology The River2D Morphology model (referred hereafter as R2DM) was originally developed in 2006 by Robert G. Millar and Jose “Pepe” Vasquez at the University of British Columbia as an add-on module to River2D (written by F. Hicks, A. Ghanem, J. Sandelin, P. Steffler, and J. Blackburn at the University of Alberta). In 2009, Stephen Kwan developed the graphical user interface, the mixed sized sediment transport module and the secondary flow correction algorithm under the guidance of Robert Millar. Stephen added the Struiksma non erodible area algorithm, advanced output features and fish egg survival algorithm in 2010. Limitations R2DM solves the bedload sediment continuity equation; suspended transport of fine material is ignored. The model is intended for modeling general bed changes, local scour, which is caused by three-dimensional flow, cannot be modeled. The upwinding scheme implemented is very simple and has not been fully tested; stability and accuracy of the solutions cannot be guaranteed. As shown in this manual, R2DM has been tested with a limited number of laboratory flume cases. Conditions of Use R2DM, in the form of a Windows XP/Vista/Windows 7 executable program, is available in the public domain. The program is supplied as seen, with no warrant of completeness or applicability to any particular problem. The program, example data files, and documentation may be freely copied and distributed as long as this notice is included and use of the model is properly acknowledged. R2DM development and the documentation is an on-going process and so whenever significant functionality is added, an updated program will be released. Any feedback (constructive or otherwise), bug reports, and discussion will be greatly appreciated. Inquiries should be directed to [email protected] or [email protected].



Contents List of Symbols .............................................................................................................................................. 4

1.0 Introduction ............................................................................................................................................ 6

2.0 Setting the Parameters for R2DM ........................................................................................................... 6

2.1 The Sediment Transport Equations .................................................................................................... 7

2.1.1 Meyer-Peter Müller Equation ........................................................................................ 8 2.1.2 Engelund-Hansen Equation ........................................................................................... 8 2.1.3 Van Rijn Equation.......................................................................................................... 8

2.1.4 Empirical Formula ......................................................................................................... 9

2.1.3 The Wilcock & Crowe (2003) Formula ......................................................................... 9 2.2 The Sediment Options Dialog Box..................................................................................................... 12

2.2.1 Upwinding Factor ........................................................................................................ 13

2.2.3 Calibration Factor for Transversal Slope ..................................................................... 14 2.2.4 Apply Downstream Water Depth................................................................................. 15 2.2.5 Apply Sandslide ........................................................................................................... 15

2.2.6 Apply Secondary Flow ................................................................................................ 15 2.2.7 Apply Inertial Adaptation ............................................................................................ 19

2.2.8 Apply Upstream Sediment Supply............................................................................... 19 2.2.9 Bed Elevation Boundary Conditions ........................................................................... 19 2.2.10 delta_a ........................................................................................................................ 19

2.2.11 Load Sediment File ................................................................................................... 19 3.0 Running a R2DM simulation ................................................................................................................. 20

4.0 Special Features .................................................................................................................................... 22

4.1 Fish Egg Survival Algorithm ............................................................................................................... 22

4.1.1 Procedure to estimate fish egg survival during a flow event ....................................... 22 4.2 Non Erodible Areas ........................................................................................................................... 23

4.2.1 Basic NEA Algorithm .................................................................................................. 23

4.2.2 Struiksma NEA Algorithm .......................................................................................... 23 5.0 Plotting Results with R2DM .................................................................................................................. 25

5.1 Vector Data ....................................................................................................................................... 25

5.2 Contour Plots .................................................................................................................................... 25

5.3 Advanced R2DM output features ..................................................................................................... 26

5.3.1 The modified “Display” menu items ........................................................................... 27 5.3.2 The “Output” menu items ............................................................................................ 31 5.3.3 Neighbour node output ................................................................................................ 35

6.0 Tutorials ................................................................................................................................................ 36

6.1 Tutorial 1: Aggradation in a Straight Flume ...................................................................................... 36

6.3 Tutorial 3: Effects of Up-winding ...................................................................................................... 40



6.4 Tutorial 4: Scour and deposition in a Curved Flume ......................................................................... 42

6.5 Tutorial 5: Mixed Sediment Transport in a Straight Flume ............................................................... 47

7.0 Advice and Trouble shooting ................................................................................................................ 49

REFERENCES ................................................................................................................................................ 50

APPENDIX .................................................................................................................................................... 51

A.1 List of output parameters for CSV file .............................................................................................. 51

A.2 List of Output parameters of DBF File .............................................................................................. 52

A.3 Header Information for a fixed bed simulation ................................................................................ 53

A.4 Header Information for a morphodynamic simulation .................................................................... 53

A.5 Header Information for a morphodynamic simulation using Wilcock and Crowe equation ........... 53

A.6 Example Sediment (.SED) File ) version 7.0 ...................................................................................... 54

A.7 Example Sediment (.SED) File ) version 7.5 ...................................................................................... 55



List of Symbols

A local element area (m2) a constant used for empirical sediment transport equation b constant used for empirical sediment transport equation c bed load-surface mixing coefficient C Chezy friction coefficient (m1/2/s) dz change in bed elevation D50 size of 50th percentile grain size Dsm median surface grain size Di grain size in fraction i fbi bed load fraction fs = k1 /k2 , calibration factor for transversal slope Fi proportion of fraction i in the surface size distribution Fb proportion of fraction i in bed load size distribution Fs proportion of sand in surface size distribution g gravitational acceleration h water depth k1 constant (used to calculate fs for transversal slope) k2 constant (used to calculate fs for transversal slope) ks effective roughness height in River2D L length of flume Ls surface layer thickness Pi proportion of fraction i in transport size distribution qs sediment transport rate per unit width qbi sediment transport rate of size fraction i per unit width qbT total bed load transfer rate qsIN upstream sediment supply rate (m2/s) qx sediment flux in x direction qy sediment flux in y direction Q sediment flux (m3/s) going into an element. s specific gravity of sediment

T = */c -1, Transport stage parameter (used for Van Rijn Equation) t time (s) u* shear velocity u velocity component in x direction UW up-winding coefficient v velocity component in y direction Wi

* dimensionless transport rate of size fraction i Wr

* reference value of dimensionless transport rate (=0.002) zb bed elevation

calibration parameter for inertial adaptation

g

porosity

sf secondary flow adaptation length factor

/ri



water density

shear stress

dimensionless Shields stress

ci critical shear stress of size fraction i

r reference shear stress

ri reference shear stress of size fraction i

rm reference shear stress of mean size of bed surface

i* dimensionless Shields stress for size fraction i

rm reference dimensionless Shields stress for mean size of bed surface



1.0 Introduction The purpose of this document is to provide direction in the use of R2DM for unsteady flow

simulations of moving beds. This document is intended as a supplement to River2D manuals and

tutorials. For this reason, it is assumed that you are familiar with the functions and interface of River2D

and transient simulations. This User Manual and Tutorial will cover the following:

Setting the parameters for R2DM

Running R2DM

Viewing the results of R2DM

A series of tutorials showing the main features of R2DM

Optional output functions

A more in-depth description of the mathematical procedure is given in Vasquez (2005) and Kwan (2009).

2.0 Setting the Parameters for R2DM In order to run a morphological model it is first necessary to specify the following:

the properties of the sediment (porosity and D50),

the sediment transport equation,

boundary conditions and

factors which affect the mathematical stability (e.g. up-winding factors, secondary flow etc).

These properties can be defined under Options->Sediment Options:

Figure 1. The “Sediment” menu items for Morphodynamic Simulations



Figure 2. Sediment Options Dialog Box

A brief explanation of the values in this dialog box and their specific use are explained below.

2.1 The Sediment Transport Equations The five equations available to compute the sediment transport relationship in River2D

Morphology are the Engelund-Hansen, Meyer-Peter-Müller, Van Rijn, an empirical formula (Kassem and

Chaudrey, 1998) and the Wilcock and Crowe (2003) mixed sediment transport model. Each equation is

generally applicable for a range of sands or gravels or both. The engineer should take care in applying

any equation to gradations outside the ranges for which the equation was derived without

understanding the potential inaccuracies in the results associated with this decision. Each sediment

transport function and its applicability are briefly presented in the following paragraphs. The two

dimensional bedload sediment continuity equation may be written as:

0)1(

y

q

x

q

t

z sysxb (1)

where qsx and qsy are the components of volumetric rate of bedload transport per unit length in x and y.

is the porosity of the bed material, t is time and zb is the bed elevation.



2.1.1 Meyer-Peter Müller Equation

The Meyer-Peter-Müller sediment transport equation (Meyer-Peter and Müller, 1948) was

based primarily on experimental flume data, but has been widely and successfully applied to rivers

having coarse bed material. The data used in developing Meyer-Peter Müller was from rivers with little

to no suspended sediment, therefore the function should perhaps not be applied to rivers with

appreciable suspended sediment. The equation has performed well for gravel-bed streams and for sand-

bed streams not carrying significant suspended load. R2DM uses a version of the Meyer-Peter Müller

equation that has been corrected by Wong and Parker (2006):

5.13

50 047.0*)1(*4 gDsqs (2)

2.1.2 Engelund-Hansen Equation

The Engelund-Hansen sediment transport equation (Engelund, 1966, Engelund and Hansen,

1967) was extensively based on flume data using four median (D50) sand particle diameters (0.19, 0.27,

0.45, and 0.93 mm). This transport function is most appropriate for sand-bed streams with a substantial

suspended sediment load. The channel bed material should have a minimum particle diameter of 0.15

mm or greater and not have a wide variation of sand gradation about the median particle diameter. The

appropriate bed form for the function is dunes.

50

2

22

)1(*

DsC

vu

(3)

5.13

50

2

*)1(05.0

Dsgg

Cqs (4)

Where s= specific gravity, g = gravitational acceleration, C= Chezy roughness, *= dimensionless shear

stress (Shield’s parameter), D50 = median particle size.

2.1.3 Van Rijn Equation

The Van Rijn equation (Van Rijn, 1984) calculates sediment transport as a function of saltation

height, particle velocity and bedload transportation:

3.0

*

1.25.1

50

5.0053.0*)1(

D

TDgsqs (5)

where:

31

250*

)1(

gsDD (6)

T = Transport stage parameter, = viscosity, s = specific gravity



2.1.4 Empirical Formula

The empirical formula (Kassem and Chaudhry, 1998) assumes that the sediment transport

depends only on the velocity according to an empirical power law:

2

122 )(

b

sx vuauq (7)

2

122 )(

b

sy vuavq (8)

where u, v are the velocity components in x and y;

a, b are empirical constants (a is ~ 0.001, notice that b ~ 3 for Meyer-Peter Muller equation while b = 5

for Engelund-Hansen equation).

2.1.3 The Wilcock & Crowe (2003) Formula

The Wilcock and Crowe (2003) formula includes the effects of sand in the calculation of gravel?

sediment transport and can be represented by the following equations:

3

*

* )1(

uF

gqsW

i

bii

(9)

35.1

894.01*14

35.1002.05.4

5.0

5.7

*

i

i

iW (10)

b

sm

i

rm

rii

D

D

*

*

(11)

)20exp(015.0021.0*

srm F (12)

)/5.1exp(1

67.0

smi DDb

(13)

where Di is grain size in fraction i, Dsm is the median surface grain size, Fs is the sand fraction on the

surface, *rm is the reference Shields stress for mean size of bed surface and W*

i is the dimensionless

transport rate for fraction i. Total transport rate, W* is found by summing all W*i.

Eq. (11) and (12) represent a hiding function in that it acts to increase ci (reducing calculated transport

rates) for finer fractions and reduce ci (increasing calculated transport rates) for coarser fractions,

relative to values of the reference shear stress for single-sized sediments. Additional initial conditions

and parameters are required if the Wilcock and Crowe formula is selected. These are:

Surface layer distribution of computational domain



Substrate distribution

Grain size distribution of sediment feed

Initial surface layer depth

Bedload – Surface mixing coefficient (0-1)

Surface – Substrate mixing coefficient (0-1) These can be set by selecting W/C settings button on the sediment options dialog box. Since the grain size distribution on the surface of a riverbed is rarely uniform, R2DM allows the user to specify a different initial distribution according to the bed roughness, ks. Figure 3 shows how the grain size distributions can be initialized for the ks ranges: ks < 0.1; 0.1 < ks < 0.3; 0.3 < ks < 0.7; 0.7 < ks < 1.0.

Figure 3. The Sediment Options Dialogue Box

2.1.3.1 The Gravel Transport Function

The gravel transport function assumes that the active surface layer remains at a constant thickness, Ls, set by the user (Depth of Surface Layer in the “Set Grain Size Distribution” dialogue box, Figure 3). At each time step the grain size distribution for the surface layer distribution is recalculated according to the volume of sediment entering or leaving the element. If there is aggradation, the net volume of



sediment into an element is positive and the new fraction of grain size i in the surface layer of the element can be calculated according to the formula:

Eisiiii AFdzLdtQQQV )1(*)()( 312312 (14)

where Vi = volume of fraction i in the surface, Fi = surface layer fraction i, and Ls = surface layer thickness, Q12i = volume of sediment in fraction i entering or leaving through side 12 of the element per unit time. If there is degradation, sediment leaves the element and the surface layer mixes with the substrate to maintain a constant Ls (see Figure 4). The new volume of fraction i is therefore:

siEisiiii FdzAFdzLdtQQQV *)1(*)()( 312312 (15)

Where Fsi is the fraction of grain size i in the substrate.

Thus, the new surface layer fraction at time step, t+t is:

)1(

AL

V

V

VF

s

i

Total

inew

s (16)

This formulation of this function models the actual physical phenomena and satisfies mass continuity.

2.1.3.2 Transport Rate Factor

Since the Wilcock and Crowe mixed sediment transport function is empirical, it may be necessary to adjust it using a weighting factor. The recommended range would be between 0.01 – 100 to remain within the range of experimental results.

Figure 4. Conceptual model of a gravel bedded river during aggradation. The bed load mixes with the surface layer to form a new grain size distribution. The surface layer thickness is assumed to be a constant thickness Ls.



Figure 5. Conceptual model of a gravel bedded river during degradation. The surface layer mixes with the sub-surface layer to form a new grain size distribution. The surface layer thickness is assumed to be a constant thickness Ls

2.1.3.3 Roughness Height

In River2D, once the roughness height, ks, is defined in the computational domain, it remains unchanged throughout the simulation since the bed morphology remains constant. For simulations where the bed and/or surface grain distribution change over time, this method of defining ks is therefore not suitable. When the mixed Wilcock and Crowe sediment transport equation is selected in R2DM, the roughness height is recalculated after the surface distribution is updated according to the following Manning- Strickler formulation:

9090 * DCks (17)

where D90 is the size of the surface material such that 90% is finer and C90 is an order-one dimensionless number. C90 is specified in the “Set Grain Size Distribution” dialogue box in Figure 3.

2.2 The Sediment Options Dialog Box The following boxes are self explanatory and do not require detailed description:

Porosity is the porosity of the sediment (0-1),

D50 is the median grain diameter in metres (required if the Wilcock and Crowe formula is not selected),

Minimum Depth for Sediment Transport (in metres),

Angle of Repose (degrees).



2.2.1 Upwinding Factor

Exner’s equation for sediment continuity can be interpreted as a combination of two physical

transport mechanisms: diffusion and convection. Under certain conditions one of these mechanisms

may dominate over the other. Under diffusive conditions, Exner’s equation can be solved using Galerkin

Finite Element Methods (GFEM). GFEM uses only the local information of the element (fluxes Q1, Q2

and Q3 at three nodes) to compute the bed changes at the element, independent of the direction of

sediment movement. However, in convection-dominated problems, such as migration of bedforms, the

direction of sediment transport is important and the GFEM becomes highly unstable and so cannot be

used. This is because convection dominated flows requires upwind numerical schemes that use the

upstream sediment transport rates to compute the bed changes in the element downstream.

R2DM employs a crude first order up-winding method that calculates the sediment flux through

each element side by simply averaging the sediment fluxes of local and upstream nodes.:

upstreamlocal QUWQUWQ **)1( (18)

where 0 ≤ UW ≤ 1 is the up-winding weighting factor. UW=1 means full up-winding, and UW=0 means no up-winding is used (conventional GFEM).

Figure 6. Example of sediment fluxes into and out of an element in the mesh.

Figure 6 illustrates an example in which an element with nodes 1, 2 and 3 has sediment entering though

sides 1-2 and 1-3, while leaving by side 2-3. Sediment fluxes through each element side will be

computed as:



AQUWQQ

UWQ *2

*)1( 2112

(19)

132

23 *2

*)1( QUWQQ

UWQ

(20)

CQUWQQ

UWQ *2

*)1( 3113

(21)

Finally, the average bed change zb at the element during a time interval t becomes in this case:

A

QQQtzb

231312*)1( (22)

2.2.3 Calibration Factor for Transversal Slope

This should be set if a strong transverse slope is expected, for example when modeling bends.

If a grain of weight W is moving along a flume with slope angle , the grain will be subject to bed

shear stress in the direction of mean flow u and the component of weight in the down slope direction

Wtan. The resultant force forms an angle with the x-axis, which is the direction of bedload transport.

Figure 7. Diagram showing the forces on a particle on a transverse slope in a flume

x

z

fDk

DkGg b

sb

s

*

1tan

)1(tan

2

1

3

2

(23)

the force caused by the bed shear stress is k1D2b

k1, k2 are constants related to the shape of the particle

the weight of the particle, W=g(s-1)k2D3

fs = k1 /k2 = calibration factor for transversal slope (typically ~ 1.5).

For 2D flow with secondary flow the equation becomes:



x

z

f

y

z

f

b

s

b

s

*

1cos

*

1sin

tan

(24)

2.2.4 Apply Downstream Water Depth

If this box is checked then the downstream water depth is fixed to the value entered by the

user. Using this function sometimes helps if there are instability problems at the outflow.

2.2.5 Apply Sandslide

This function ensures that the bed slopes remain equal or lower to the maximum bed slope as

defined by the angle of repose, , of the bed material. If the bed slope remains well below then leave

this check box unchecked. This function has not been fully tested (for further information on the

algorithm used see Vasquez, 2005).

2.2.6 Apply Secondary Flow

Check this box for modeling bends.

Figure 8. Diagram illustrating how secondary flow is formed.



Figure 9. Typical cross section at a natural river bend (after Henderson, 1966).

Figure 10. Deviation of bed shear stress around bends.



Flows in curved channels have a centripetal acceleration, ac of the order u2/r where r is the

radius of curvature of a streamline. ac reaches a maximum close to the surface of the water where

velocity is close to maximum. Therefore, at a cross section in the bend of a channel the surface layers of

water are pushed outwards. In order to satisfy mass conservation, water in the lower layers close to the

bed must move inwards. When this secondary flow circulation combines with the primary flow it

generates a spiral motion characteristic of flow in bends. The inward motion near the bed transports

sediment from the outer bank, where scour occurs towards the inner bank where deposition occurs.

Therefore, the magnitude of the bed changes is proportional to the intensity of the secondary motion.

Radius of Curvature

The local radius of curvature of the streamline can be computed for each node in the unstructured

mesh. Three points are required along the same streamline (Figure 11); the node (x2, y2), plus one point

upstream and downstream. In practice we have found that having the points separated by a distance

between 5 and 10 elements yields stable results. The equation of the circle that passes through these

three coordinates can then be determined by solving the following determinant:

||

|| = 0 (25)

By expanding this 4x4 determinant and transforming it into the form:

( ) ( ) (26)

explicit expressions are obtained for the coordinates of the center of the circle (h, k) and radius of curvature rc:

(

)( ) (

)( ) (

)( )

( )

(27)

(

)( ) (

)( ) (

)( )

( )

(28)

(

)( ) (

)( ) (

)( )

(29)



Figure 11. Points located along the same streamline used to calculate the local value of rc at the node (x2, y2).

This approach to calculate the local radius of curvature has proven to be numerically stable, can be

applied to irregular and complex river geometries, and does not require a priori assumptions of

streamline geometries.

2.2.6.1 Applying secondary flow correction

1. Calculate the cumulative discharge. Flow>Cumulative Discharge

2. Check the “Apply Secondary Flow Correction” check box

3. Specify a number (~5-10) for Nc

4. Bed Shear Deviation Angle (shown under “Curvature”) and 1/radius can be displayed under

Display>Contour/Colour only during or after a morphodynamic simulation.

5. If 1/radius looks odd then stop the simulation and change the Nc value.

Figure 12 shows the bed shear deviation angle in a typical river.

Figure 12. Bed shear deviation angle in a typical meandering river . When the channel bends towards the right the bed deviation angle is positive. When the channel bends to the left the bed deviation angle is negative



2.2.7 Apply Inertial Adaptation

This function should be used when the Apply Secondary Flow option is also selected. In curved

channel, the curvature of a streamline can be calculated at every time step during a simulation but this

process is very time consuming and can lead to mathematical instabilities if the velocity gradients vary

suddenly. An alternative approach is to compute the curvature only at the beginning of the

computation. However, since this initial curvature lags behind the final value, an inertial adaptation

equation is required (Rozovskii 1957, Stuiksma et al. 1985).

322

111

u

au

rryv

rxu

vu

sf

(30)

where

g

Chsf (31)

The secondary flow adaptation length, which is a function of water depth, h, roughness, C, and where

is the user entered calibration parameter between 0.4 – 2.

2.2.8 Apply Upstream Sediment Supply

If checked this means that the inflow of upstream sediment supply is forced to a value set by the

user. Unchecked (default option) means that the sediment is in equilibrium condition, i.e the flow

transports sediment at full capacity.

2.2.9 Bed Elevation Boundary Conditions

For modeling flume experiments the inflow and/or outflow bed elevations are usually known so

you can choose one of the following boundary conditions:

Bed Elevation fixed at inflow/outflow

Bed Elevation fixed at inflow

Bed Elevation fixed at outflow

For natural river beds the boundary conditions are usually not fixed and so you should choose the “Bed

Elevation Free” option.

2.2.10 delta_a

This is used for the Struiksma NEA algorithm and is described in 4.2.2.

2.2.11 Load Sediment File

Instead of manually entering the data into the sediment options dialogue box the data can be read in

from a sediment (.SED) file. The different formats (depending on the version you are using) of the .SED

file are given in the Appendix. DO NOT add any more lines to .SED file but simply change the numbers

associated with each variable.



3.0 Running a R2DM simulation The normal steps involved in modeling transient sediment flow with R2DM are as follows:

1. Calibrate the hydrodynamic model for a given flow scenario by adjusting the roughness values (bed values for open water, bed) until model results agree with observed data.

2. Run a model using the steady solver until it reaches steady state. 3. Save the CGD file. 4. Load the CGD file for the initial conditions for the morphological simulation. 5. Specify parameter for the morphological flow simulation in the “Sediment Options” Dialog box

or load a SED file. 6. Select the “Run Morphology” option (it replaces the Run Transient option) under the

“Hydrodynamics” menu item. 7. Select the type and frequency of transient output for the simulation (if any is desired).

All the information pertaining to a morphodynamic simulation are under the “Sediment” menu item.

Figure 13. The Sediment “menu” item.



The “Run Transient” dialog box has been modified so that the user can select either “fixed bed”

(default River2D) or “morphodynamic” simulations (see Figure 14).

Figure 14. The modified “Run Transient” dialog box and the “Transient Output Options” dialog box.

A Transient Tecplot file can be created when the “Create transient Tecplot (.dat) and point output (.csv)”

check box is checked (Figure 14). Standard Tecplot dumps can also be created at regular time step

intervals when the “tecplot output” check box is checked.



4.0 Special Features

4.1 Fish Egg Survival Algorithm R2DM has been adapted to include a feature to predict the survival rate of salmon redds during high

flow events by calculating the Dscour and Dfill. To do this, the locations and depths of the redds (Dredd ) are

specified by loading a “redd” file into R2DM at the start of a morphodynamic simulation. The Redd file is

in the same format as a .BED file except that the 5th column is the redd burial depth rather than ks and

can be created using the River2D_Bed program. When the redd file has been loaded, the redd survival is

set to “1” in each node of the computational domain where the Dredd > 0. During a morphodynamic

simulation the Dscour and Dfill is checked at each node after every time step. If Dscour or Dfill is greater than

or equal to Dredd, redd survival is set to “0.” The overall survival rate can then be calculated by

summation of the “redd survival” in the entire computational domain" and comparing that to the

original survival rate (i.e., the amount of original eggs) prior to the simulation.

Figure 15. Profile of a) net aggradation (fill) and b) net degradation (scour).

4.1.1 Procedure to estimate fish egg survival during a flow event

1. Get a converged steady state River2D simulation.

2. Specify the redd burial depth in a .RED file using the River2D Bed editor.

3. Load the Redd file.

4. Specify the Sediment properties or load a .SED file.

5. Calculate Fish Egg Survival (This gives the number of nodes which contain fish eggs). Note this

number (Sintial) down because it will not be stored during the simulation.

6. Run a morphodynamic simulation.

7. Calculate Fish Egg Survival again to get Sfinal. Percentage of Redd Survival = Sinitial/Sfinal x 100%.

For more information see Glawdel et al. (2011).



4.2 Non Erodible Areas Two algorithms are available for dealing with non erodible areas.

4.2.1 Basic NEA Algorithm

In R2DM version 7 the “Load Non Erodible Areas” option replaces the “Load Channel Index File” option

in River2D. The non erodible area file (extension .nea) can be used to identify areas where the bed

cannot be eroded (e.g concrete areas). The structure of the.nea file is identical to a .bed file except that

the channel roughness parameter for each point is replaced by:

1000 for area which cannot erode away 0.1 for areas of natural bed material The R2D_Bed utility can be used to aid the generation of the NEA file.

4.2.2 Struiksma NEA Algorithm

In R2DM version 7.5 the Non Erodible Areas file (.NEA) has the same format as a .BED file. The elevation

in the .NEA file is the elevation at which no more bed material can be eroded away. When the .NEA file

is loaded, a correction factor, is applied to the sediment transport rate qs as the bed elevation

approaches the non erodible layer.

[

] for

(31)

Figure 16. Sketch of bed and non erodible layer (shaded region). Zb = bed elevation, Z = elevation of non erodible layer. After Struiksma (1999).



Figure 17. Variation in correction factor when the bed nears the non-erodible layer.

0

0.2

0.4

0.6

0.8

1

1.2

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

corr

ect

ion

_fa

cto

r

delta

deltaA=1

deltaA=2

deltaA=3

deltaA=4



5.0 Plotting Results with R2DM

5.1 Vector Data The information related to bed morphology can be displayed using the same output options as

River2D. In the “Vector Plot” dialog box the “Sediment Transport” option replaces the “Discharge

Intensity”:

Figure 18. Vector Plot Dialog Box

5.2 Contour Plots In the “Contour Plot” dialog box, the following options have been added:

Curvature

qsx (x-component of sediment flux)

qsy (y-component of sediment flux)

qs (sediment flux)

Bed Change

Figure 19. Colour/Contour Dialog Box



If the Wilcock and Crowe sediment transport equation is used, then the following parameters can be

displayed:

D50 (Substrate)

D50 (Surface)

D50 (Bed load)

D90 (Substrate)

D90 (Surface)

D90 (Bed load)

Sand Fraction

Surface Layer Thickness

If the D90 is selected the percent finer distribution will be displayed when the mouse is moved over the

flow field.

5.3 Advanced R2DM output features River2D version 7.5 has been upgraded to include the following features:

1. Multiple variable output dumps.

2. SHAPE file output nodal and grid dumps.

3. SHAPE file output for water’s edge.

4. ESRI ASCII files output for grid dumps.

5. STL files used for 3D CFD simulations.

6. T3S files used to Telemac2D simulations.

7. PHOENICS BFC grid file.

8. TECPLOT output for all hydraulic, habitat and morphodynamic variables.

9. Transient TECPLOT output.

10. Neighbour node output (list of the nodes within a user specified distance of each node).

11. Output files include simulation data in header.

This section gives an overview of these new features.



5.3.1 The modified “Display” menu items

Figure 20. The modified “Display” menu options.

5.3.1.1 Dump Grid CSV file

Display>Dump Grid CSV file…

The Dump grid CSV file output option has been modified so that the variables in Table 1 in the Appendix

are all output simultaneously (in the standard River2D, only the display variable is output). Also output

are the details of the simulation which are displayed in the Header (see Appendix).

5.3.1.2 Zoom and Dump Grid CSV file

Display>Zoom and dump grid CSC file…

This performs the same function as the Zoom on Rectangle function but dumps a grid CSV containing all

the variables.

5.3.1.3 Create Body Fitted Coordinate grid file

Display>Zoom and dump READCO file…

This performs the same function as the Zoom on Rectangle function but dumps a 3D body fitted

coordinate grid in the PHOENICS Readco format. Two type sof grid can be output:



1. The bottom of the BFC grid follows the bed topography and the top is a flat surface (Figure 21).

2. The top and bottom of the BFC grid follow the bed topography (Figure 22).

The specifications of the grid are input from the .BFC file (Input>read BFC file..) which has the format:

zmax -50 numz 10 xoffset 405000 yoffset 7783000 zmax If this number is positive then zmax is the top elevation of the grid (format 1). If this number is negative then the absolute number represents the height between the top and lower surfaces of the grid (format 2). E.g in the above example the top cell is 50 m higher than the bottom cell. numz is the number of cells in the z direction The PHOENICS program reads in the numbers in scientific format (6E12.6) so if the coordinate system of

your CDG file is in UTM it will be necessary to decrease the numbers by specifying xoffset and yoffset.

For example, if your area is within the region (405001, 7783000) and (405900,7783900) then xoffset=

405000 and yoffset=7783000; and coordinate (405050,7783100) will become (50,100).

After the file is created you will need to edit the numbers using a text editor since C++ creates scientific

number in the format, 5.486534e+005 whereas PHOENICS requires them in the format, 5.486534e+05.

Use a text editor (e.g notepad) to replace e+00 with e+0.

Figure 21. Body fitted coordinate grid with flat upper surface (format 1).



Figure 22. Body fitted coordinate with top surface following the bed topography (format 2).

5.3.1.4 Extract Section to CSV file

Display>Extract section to CSV file…

This feature has been modified so that the mouse can be used to select the points. More than 2 points

can be selected by clicking on the “Select points using mouse” button. This makes it particularly useful

for extracting the points along the thalweg of a river. There is no limit to the number of points selected

but the points must be in sequential order. All the variables (see Table 1) are output for each dump.

Figure 23. The new dialog box for extracting the points along a section.



5.3.1.5 Dump HEC RAS Cross Sections

Display>Dump HEC RAS Cross Sections

This feature creates a CSV file containing the cross sections along the thalweg of the river. When this

feature is selected the dialogue box shown in Figure 23 pops up.

Point spacing = distance between each point on the cross section.

Hec Ras XS width = width of each cross section.

Press the “Select points using mouse” button and then select points along the thalweg (starting

upstream) using the mouse. A cross section is created at each location except on the first point. The

cross sections are labeled starting from 7000 and then decrement in steps of 10 (Figure 24).

Figure 24. Bed Elevation and Hec Ras Cross Sections (plotted using Global Mapper)

To load the Hec Ras cross section file into Hec Ras the following steps are required:

1. Take off the header information (first 5 lines)

2. Open a new HEC RAS project

3. In the Geometric Data Editor, goto File>Import Geometry Data>CSV Format

4. Select your R2DM Hec Ras file and choose the default X,Y,Z Format option.

5. At this stage you will have to manually work out the left, right and channel reaches using excel.



5.3.2 The “Output” menu items

The new HEC River2DM features are organized in the “Output” Menu option.

Figure 25. The new “Output” menu items.

5.3.2.1 Dump nodal SHP file

Output>Dump nodal SHAPE file

This creates an ESRI shape file containing the data shown in Table 2 at each node of the computational

domain.

5.3.2.2 Dump Grid SHP (using the Mouse)

Extract Grid: Output>Dump grid SHP file.

To extract a grid dump, the mouse is used to select the 2 corners of the grid. The order in which they are

selected does not matter and the user can define either the NE and SW corners or the NW and SE

corners (see Figure 3). CSV, SHP and ASC files are created each time. CSV and SHP files contain multiple

variables but the ASC file contains only the display variable.

5.3.2.3 Dump water edge SHP File

Output>Dump water’s edge SHP file.

Selecting this option creates an ESRI polyline shape file of the water’s edge.



Figure 26. Two corner must be selected to extract a Grid CSV or SHP file. file and the points extracted using the new “Extract points to CSV/SHP File” command.

5.3.2.4 Tecplot Output

Output>Dump TECPLOT file

This feature dumps the variables in Table 2 into an ASCII .dat Tecplot file. Details of the simulation are

given in the Header (see Appendix).

Figure 27. Tecplot contour plot of velocity.



5.3.2.5 Blue Kenue Output

Output>Dump T3D file for Blue Kenue

This feature is used for exporting a River2D mesh to Telemac2D. It creates the following 6 T3S files:

1. NAME_BOTTOM.T3S

2. NAME_FREESURFACE.T3S

3. NAME_FRICTION.T3S (This is the bed roughness Ks)

4. NAME_DEPTH.T3S

5. NAME_VELOCITYU.T3S

6. NAME_VELOCITYV.T3S

Where NAME is specified by the user.

NAME_BOTTOM is used to create the geometry file for BLUE KENUE. The other files can be used to

create a selafin file containing the initial conditions.

5.3.2.6 STL Output

Output>Create STL file for Riverbed Output>Create STL file of water surface>Base Output>Create STL file of water surface>Lid

STL files are 3D files which describe a solid object and can be exported to CFD software programs such

as Flow3D, PHOENICS, CFX etc. HEC River2DM creates STL files for the river bed from the mesh. The

water surface can also be exported as an STL file and used as the “lid” for a “rigid lid” simulation. Figure

28 shows the bed elevation in a typical CDG file and Figure 29 shows the corresponding STL file.



Figure 28. Elevation of a typical area

Figure 29. STL file of the terrain created from the CDG file shown in Figure 28.



5.3.3 Neighbour node output

Output>Dump neighbour node file

Outputs all the neighbours of each node within a distance specified in the “FISH” file. The .FIS file has

the format:

Swim_distance <distance in metres> Max_neighbours <number> To load a "Fish file" goto Habitat > Load FISH file.



6.0 Tutorials

6.1 Tutorial 1: Aggradation in a Straight Flume The flume used by Soni et al. (1980) uses a straight flume of length=30m, width = 0.2m with an initial

bed slope of 0.036 and covered by uniform sand with a median diameter of 0.32mm.

1. Launch R2DM. 2. Choose File->Open SONI-STEADY.CGD. 3. Choose Options->Sediment Options. Set the parameters to those shown in Figure 30. 4. Choose Hydrodynamics->Run Morphology. Set present time = 0, Final time = 2400, time step = 0.1. 5. Choose Point Output (.csv file format). To save an excel file of the transient solution at various time

steps: a. select a CSV file containing the coordinates (in this case choose SONI-cords.CSV. b. select box “Bed Elevation” so that you can see the bed changes. c. select an appropriate name and destination folder for the file. d. output the variable data every 100 time steps.

6. When the simulation is complete, open the CSV file and plot the bed height at t=15 minutes and t=40 minutes.

7. Repeat simulation with a different sediment input rate.

Figure 30. Parameters for the Tutorial 1: Aggradation in a Straight Flume.



Figure 31. Computed longitudinal profiles at 15 and 40 min in the “Soni” flume.

Aggradation in the Soni Flume

0.56

0.58

0.6

0.62

0.64

0.66

0.68

0.7

0.72

0.74

0 5 10 15 20

Distance (m)

Bed

Ele

vati

on

(m

) initial bed

t = 15 min

t = 40 min



6.2 Tutorial 2: Degradation in a Straight Flume

The flume used by Suryanarayana (1969) uses a straight flume of length=18.29m, width = 0.61m with an

initial bed slope of 0.007 and covered by uniform sand with a median diameter of 0.45mm. Bed

degradation occurs when the upstream sediment supply is shut off.

1. Launch R2DM. 2. Choose File->Open SURY-STEADY.CGD. 3. Choose Options->Sediment Options. Set the parameters to those shown in Figure 32. 4. Make sure that you select “Apply Upstream Sediment Supply” and set Upstream sediment supply =

0 to ensure that there no sediment enters at the inflow. 5. Choose Hydrodynamics->Run Morphology. Set present time = 0, Final time = 36000, time step = 0.1. 6. Choose Point Output (.csv file format). To save an excel file of the transient solution at various time

steps: 7. Select a CSV file containing the coordinates (in this case choose SURY-cords.CSV. 8. Select box “Bed Elevation” so that you can see the bed changes. 9. Select an appropriate name and destination folder for the file. 10. Output the variable data every 100 time steps. 11. When the simulation is complete, open the CSV file and plot the bed height at t=36000s (10 hours). 12. The bed profile is shown in Figure 33.

Figure 32 Parameters used for Suryanarayana (1969) degradation experiment.



Figure 33 Computed bed profile after 10 hours in the flume used by Suryanarayana (1969). Degradation at the inflow is caused by sediment supply shut off.

These aggradation and degradation test cases were reported by Vasquez et al. (2007).

Degradation in a flume

0.15

0.17

0.19

0.21

0.23

0.25

0.27

0.29

0.31

0.33

0 2 4 6 8 10 12 14 16 18

Distance (m)

Bed

Ele

vati

on

(m

)

Original Bed

R2DM

Observed



6.3 Tutorial 3: Effects of Up-winding This tutorial illustrates the effects of increasing the up-winding coefficient on a bed form shaped with a

Gaussian distribution.

1. Launch R2DM. 2. Choose File->Open GAUSSIAN-STEADY.CGD. 3. Choose Options->Sediment Options. Set the parameters to those shown in Figure 34. 4. Choose Hydrodynamics->Run Morphology. Set present time = 0, Final time = 1000, time step = 1. 5. Choose Point Output (.csv file format). To save an excel file of the transient solution at various time

steps: 6. Select a CSV file containing the coordinates (in this case choose GAUSSIAN-cords.CSV. 7. Select box “Bed Elevation” so that you can see the bed changes. 8. Select an appropriate name and destination folder for the file. 9. Output the variable data every 200 time steps. 10. When the simulation is complete, open the CSV file and plot the bed height at various time steps. 11. Repeat the simulation with different lower up-winding coefficients. 12. Bed profiles with different up-winding coefficients are shown in Figure 35.

Figure 34. Parameters for Tutorial 3: Effects of Up-winding.

Figure 34 below shows that increasing the up-winding coefficient also increases the stability of moving

bed forms.



Figure 35. Bed elevation profiles showing the effects of changing the up-winding coefficient

Upwinding coefficient = 0.3

-0.5

0

0.5

1

1.5

2

2.5

100 110 120 130 140 150 160 170 180 190 200

Distance (m)

Ele

vati

on

(m

) 201s

401s

601s

801s

1000s

Upwinding coefficient = 0.8

-0.5

0

0.5

1

1.5

2

2.5

100 110 120 130 140 150 160 170 180 190 200

Distance (m)

Ele

vati

on

(m

) 201s

401s

601s

801s

1000s



6.4 Tutorial 4: Scour and deposition in a Curved Flume This tutorial illustrates the effects of using secondary flow correction. We use the Laboratory of Fluid

Mechanics (LFM) flume which has a 180-degree bend with a radius R = 4.25 m, width b = 1.7 m, water

depth h = 0.20 m and discharge Q = 170 L/s.

1) Launch R2DM. 2) Choose File->Open LFM-STEADY.CGD. 3) Choose Options->Sediment Options. Set the parameters to those shown in Figure 36. 4) Choose Hydrodynamics->Run Morphology. Set present time = 0, Final time = 10800. 5) Choose Output Options. To save a video file of the transient solution: check “Video output”, select

an appropriate name and choose a screen resolution. 6) To save a CGD file at particular time intervals: Check the “cdp output” box, select a prefix for the

filenames, a place to store the outputs and the time interval.

Figure 36. Morphology Output Options Dialog Box

Notice that shear stress distribution shows maximum shear in the entrance to the bend along the inner

bank, while shear stress is minimum along the opposite outside bank.



Figure 37. Diagram showing the shear stress in the LFM Flume with parameters and boundary conditions shown in the Sediment Options Dialog box

First, run the model without activating the secondary flow correction, using dt = 60s and final time of 3

hours.

Figure 38. Run Morphology Dialog box showing time step used.



Figure 39. Diagram showing bed changes without secondary flow correction.

The results of the model without secondary flow correction show scour at the entrance to the bend

along the inner (right) bank. These results are not correct, since this should be an area of sediment

deposition where a point bar develops. This is because the model is scouring where the depth-averaged

bed shear stress is high, neglecting the effects of three-dimensional helical motion that generates a

secondary flow in the transverse direction from the outer bank –where scour occurs- to the inner bank

where a point bar forms.

Let’s re-run the model but now applying the secondary flow with a transverse slope factor fs = 2.0 and

inertial adaptation parameter = 0.4. The new results show the correct pattern of deposition along the

inner bank and scour along the outer bank.



Figure 40. Diagram showing bed changes with secondary flow correction

The effect of the secondary flow correction is to make the sediment transport direction deviate from the

depth-averaged flow velocity direction. It makes sediment follow the near-bed velocity direction instead

which in bends (because of the helical flow) is directed from the outer bank to the inner bank.

Morhodynamic simulations of the LFM flume and the Waal River were reported by Vasquez et al. (2008).



Figure 41. Diagram showing velocity vectors of flow and bed load transport.



6.5 Tutorial 5: Mixed Sediment Transport in a Straight Flume This tutorial uses The St Anthony Falls Laboratory flume (SAFL) is a straight flume 50m long, 0.305m

wide and has a slope of 0.002.

1. Launch R2DM. 2. Choose File->Open SAFL-STEADY.CGD. 3. Choose Options->Sediment Options. Set the parameters to those shown in Figure 42. 4. Leave the Wilcock and Crowe parameters at default values. 5. Choose Hydrodynamics->Run Morphology. Set present time = 0, Final time = 60600, max time

step = 1.0. 6. Choose Point Output (.csv file format). To save an excel file of the transient solution at various

time steps: a. select a CSV file containing the coordinates (in this case choose SAFL-50m cords.csv. b. select box “Bed Elevation” so that you can see the bed changes. c. select an appropriate name and destination folder for the file. d. output the variable data every 3600 time steps (every hour if t=1).

7. When the simulation is complete, open the CSV file and plot the bed height at various time steps.

8. Repeat the simulation with a different surface grain distribution. 9. Computed bed profiles are shown in Figure 43.

Figure 42 Parameters used for Tutorial 5: Mixed Sediment Transport in a Straight Flume.



Figure 43 Computed bed profiles along the “SAFL” flume at 2, 8, 16.83 hours compared with experimental results.

Mixed Sediment Transport in a Straight Flume

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 5 10 15 20 25 30 35 40 45 50

Distance (m)

Bed

Ele

vati

on

(m

)

2 hr

8 hr

16.83 hr

2 hr (measured)

8 hr (measured)

16.83 hr (measured)



7.0 Advice and Trouble shooting i. Morphodynamic simulations usually demand long CPU times, for large domains a mesh coarser

than normally used for flow simulations is sometimes required. ii. For sand bed rivers, equilibrium upstream boundary condition and the Engelund-Hansen

equation usually provide reasonable results. iii. The test cases shown of aggradation, degradation and bend scour were best modeled without

using upwinding (UW=0) because of its diffusive nature. iv. If spurious migrating bedforms are observed, this may indicate the need for upwinding. v. In areas with very high local velocity sediment will normally go into suspension and will be

carried away by the flow. Since suspension is ignored by R2DM, sediment eroded will immediately deposit downstream where velocity is lower, potentially leading to numerical instabilities.

vi. If the simulation crashes early on, try using a smaller time step. vii. If the simulation still crashes, you may have to change the roughness, ks, in the bed file,

generate a new mesh, and then run a fresh steady state simulation. viii. Do not stop and start a mixed sediment simulation (the Wilcock and Crowe feature) because this

will alter your results. (At the start of a simulation, the surface grain distribution resets to the initial values)

ix. Do not stop and start a sediment simulation with secondary flow because this will alter your results since at the start of a simulation, the radius of curvature is computed.



REFERENCES Engelund, F., and Hansen, E. (1967). ”A Monograph on Sediment Transport in Alluvial Streams,”

Technical Forlag, Copenhagen, Denmark

Glawdel, J., Kwan, S., Naghibi, A., Millar, R. G., and Lence, B., Using River2D Morphology to Predict

Salmon Redd Survival during High Flow Events from Hydroelectric Dam Operations, World

Environmental & Water Resources Congress 2011, Palm Springs, May 22, 2011.

Kassem, A. A. and Chaudhry, M. H. (1998). Comparison of Coupled and Semicoupled Numerical Models

for Alluvial Channels. Journal of Hydraulic Engineering, 124(8): 792502.

Kwan, S. (2009) Masters Thesis: A Two Dimensional Surface-based, Mixed Sediment Transport and River

Morphology Model, University of British Columbia, Canada.

Rozovskii, J. L. (1957). Flow of water in bends of open channel. Academic Science of the Ukraine SSR,

Kiev.

Soni, J. P., Garde, R. J., and Ranga Raju, K. G. (1980). Aggradation in streams due to overloading, Journal

of Hydraulic Engineering, ASCE, 106: 117-132.

Struiksma, N. (1985). Prediction of 2-D bed topography in rivers, Journal of Hydraulic Engineering,

111(8): 1169-1182.

Struiksma, N, Mathematical modeling of bedload transport over non-erodible layers, IAHR Symposium

on River, Coastal and Estuarine Morphodynamics, Genova, Sept 1999, proceedings p. 89-98.

Suryanarayanara, B. (1969) PhD Thesis: Mechanics of degradation and aggradation in a laboratory

flume, Colorado State University, Fort Collins, USA.

Van Rijn, L.C. (1984). Sediment Transport, Part I: Bed load transport, Journal of Hydraulic Engineering,

ASCE, no 10.

Vasquez, J. A. (2005) PhD Thesis: Two Dimensional Finite Element River Morphology Model. University of

British Columbia, Canada.

Vasquez, J. A., Millar, R.G., and Steffler, P.M. (2007). Two Dimensional Finite Element River Morphology

Model. Canadian Journal of Civil Engineering, 34:752-760.

Vasquez, J. A., Steffler, P.M., and Millar, R.G. (2008). Modeling Bed Changes in Meandering Rivers Using

Triangular Finite Elements. Journal of Hydraulic Engineering, 134(9): 1348-1352.

Wilcock, P. R. and Crowe, J. C. (2003), Surface-based transport model for mixed-sized sediment, Journal

of Hydraulic Engineering, 129(2), 120-128.

Wong, M. and Parker, G. (2006). Re-Analysis and Correction Of Bedload Relation Of Meyer-Peter and

Müller using their own Database. Journal of Hydraulic Engineering, 132(11): 1159-1168.



APPENDIX

A.1 List of output parameters for CSV file Table 1. List of output parameters for CSV file

parameter description units

n number

negative value indicates point not in computational domain

x x coordinate m

y y coordinate m

z bed elevation m

wse water surface elevation m

depth depth m

ks roughness height m

vx x velocity m/s

vy y velocity m/s

vel velocity magnitude m/s

ci channel index none

dsi depth suitability index none

vsi velocity suitability index none

ssi substrate suitability index none

csi combined suitability index none

wua weighted usable area m2

qs sediment flux m2/s

tau shear stress Pa

qx x discharge m2/s

qy y discharge m2/s

cumd cumulative discharge m3/s

display display parameter



A.2 List of Output parameters of DBF File Table 2. List of output parameters for DBF file (part of the ESRI SHP file).

parameter description units

x x coordinate m

y y coordinate m

z bed elevation m

wse water surface elevation m

d depth m

ks roughness height m

vx x velocity m/s

vy y velocity m/s

vel velocity magnitude m/s

ci channel index none

dsi depth suitability index none

vsi velocity suitability index none

ssi substrate suitability index none

csi combined suitability index none

wua weighted usable area m2

qs sediment flux m2/s

tau shear stress Pa

qx x discharge m2/s

qy y discharge m2/s

cumd cumulative discharge m3/s

wd wet=1; dry=0

n number none



A.3 Header Information for a fixed bed simulation # C:\Users\Nelly\Desktop\files\8-1-2010 17cms converged.CDG # Date: 6/23/2010 # Time: 15:26:21 # fixed bed simulation

A.4 Header Information for a morphodynamic simulation # C:\Users\Nelly\Desktop\files\8-1-2010 17cms converged.CDG # Date: 6/23/2010 # Time: 16:21:45 # Porosity:, 0.3000 # Upstream Sediment Supply:, 0.0000 # Upwinding Factor:, 0.9000 # Engelund-Hansen Equation used # D50:, 0.0003

A.5 Header Information for a morphodynamic simulation using Wilcock and

Crowe equation # C:\Users\Nelly\Desktop\files\8-1-2010 17cms converged.CDG # Date: 6/23/2010 # Time: 16:33:4 # Porosity:, 0.4 # Upstream Sediment Supply:, 0 # Upwinding Factor:, 0.8 # Wilcock and Crowe Equation used # Sediment sizes (mm):,256,128,64,32,16,8,4,2,1,0.5,0.25,0.125 # Feed:,100,100,100,90,73,56,42,33,30,15,6,0, # Initial Surface Ks < 0.1:, 100,90,80,70,60,56,42,33,30,15,6,0, # Initial Surface 0.3< Ks < 0.1:, 100,90,80,70,60,56,42,33,30,15,6,0, # Initial Surface 0.7< Ks < 0.3:, 100,90,80,70,60,56,42,33,30,15,6,0, # Initial Surface 1< Ks < 0.7:, 100,90,80,70,60,56,42,33,30,15,6,0, # Initial Substrate:, 100,90,80,70,60,56,42,33,30,15,6,0, # Wilcock and Crowe weighting factor:, 0.1 # Initial Surface Layer Thickness:, 0.05 # Ks factor:, 2.5



A.6 Example Sediment (.SED) File ) version 7.0 Min_Depth 0.001 Repose_Angle 45 Porosity 0.4 Sediment_Supply 0 UW_Factor 0.9 TransverSlope_Factor 1.25 Length_Factor 0.4 DStreamWaterDepth 0.2 StreamDistance 10.0 ApplySed_Supply 0 ApplyInertial_Adaptation 0 ApplySecondary_Flow 1 SandSlide 0 ApplyDstreamWaterDepth 0 BEF 1 BEIO 0 BEI 0 BEO 0 MPM 0 Engelund 1 Empirical 0 VanRijn 0 D50 0.0003 a 1.786e-4 b 3.878 WilcockCrowe 0 WC_Factor 0.1 SLThickness 0.05 Ks_Factor 2.5 Feed 100 100 100 90 73 56 42 33 30 15 6 0 Subsurface 100 90 80 70 60 56 42 33 30 15 6 0 Ks_boundaries 0.1 0.3 0.7 1 Ks1 100 90 80 70 60 56 42 33 30 15 6 0 Ks2 100 90 80 70 60 56 42 33 30 15 6 0 Ks3 100 90 80 70 60 56 42 33 30 15 6 0 Ks4 100 90 80 70 60 56 42 33 30 15 6 0 velocity 0 0.35 0.56 1.0 0.6 0.18 0 0 0 0 0 0 depth 0 0.18 0.34 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 CI 0 0.1 0.2 0.3 0.5 0.9 1.0 1.0 0.4 0.2 0 0



A.7 Example Sediment (.SED) File ) version 7.5 Min_Depth 1.0 Repose_Angle 45 Porosity 0.4 Sediment_Supply 0 UW_Factor 0.8 TransverSlope_Factor 1.25 Length_Factor 0.4 DStreamWaterDepth 10 StreamDistance 10.0 deltaA 1.001 ApplySed_Supply 0 ApplyInertial_Adaptation 0 ApplySecondary_Flow 0 SandSlide 0 ApplyDstreamWaterDepth 0 BEF 1 BEIO 0 BEI 0 BEO 0 MPM 0 Engelund 1 Empirical 0 VanRijn 0 D50 0.0001 a 1.786e-4 b 3.878 WilcockCrowe 0 WC_Factor 0.1 SLThickness 0.05 Ks_Factor 2.5 Feed 100 100 100 90 73 56 42 33 30 15 6 0 Subsurface 100 90 80 70 60 56 42 33 30 15 6 0 Ks_boundaries 0.1 0.3 0.7 1 Ks1 100 90 80 70 60 56 42 33 30 15 6 0 Ks2 100 90 80 70 60 56 42 33 30 15 6 0 Ks3 100 90 80 70 60 56 42 33 30 15 6 0 Ks4 100 90 80 70 60 56 42 33 30 15 6 0 velocity 0 0.35 0.56 1.0 0.6 0.18 0 0 0 0 0 0 depth 0 0.18 0.34 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 CI 0 0.1 0.2 0.3 0.5 0.9 1.0 1.0 0.4 0.2 0 0

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