Model:TopoFlow-Channels-Diffusive Wave

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Contact

Name Scott Peckham
Type of contact Model developer
Institute / Organization CSDMS, INSTAAR, University of Colorado
Postal address 1 1560 30th street
Postal address 2
Town / City Boulder
Postal code 80305
State Colorado
Country USA"USA" is not in the list (Afghanistan, Albania, Algeria, Andorra, Angola, Antigua and Barbuda, Argentina, Armenia, Australia, Austria, ...) of allowed values for the "Country" property.
Email address Scott.Peckham@colorado.edu
Phone 303-492-6752
Fax



TopoFlow-Channels-Diffusive Wave


Metadata

Summary

Also known as
Model type Single
Model part of larger framework
Note on status model
Date note status model

Technical specs

Supported platforms
Unix, Linux, Mac OS, Windows
Other platform
Programming language

Python

Other program language NumPy (Python package for scientific computing)
Code optimized Single Processor
Multiple processors implemented
Nr of distributed processors
Nr of shared processors
Start year development 2001
Does model development still take place? Yes
If above answer is no, provide end year model development
Code development status
When did you indicate the 'code development status'?
Model availability As code
Source code availability
(Or provide future intension)
Through CSDMS repository
Source web address
Source csdms web address
Program license type Apache public license
Program license type other
Memory requirements Standard
Typical run time Minutes to hours


In/Output

Describe input parameters [[Describe input parameters model::Description of input variables
  • flow_codes = D8 flow codes (Jenson convention) [NE,E,SE,S,SW,W,NW,N] → [1,2,4,8,16,32,64,128]
  • bed_slope = slope of the channel bed or hillslope [m / m]
  • Manning_n = Manning roughness parameter [s / m1/3]
  • bed_width = bed width for trapezoidal cross-section [m]
  • bank_angle = bank angle for trapezoid [deg] (from vertical)
  • sinuosity = channel sinuosity [unitless] (along-channel / straight length)
  • init_depth = initial water depth [m] (See HTML help)

The input variable entrees through the GUI will be the following:

*Method code:            2
*Method name:            Diffusive_Wave
*Manning flag:           1
*Law of Wall flag:       0
*Time step:              Scalar         6.00000000          [sec]
*D8 flow code:           Grid           Treynor_flow.rtg    [none]
*D8 slope:               Grid           Treynor_slope.rtg   [m/m]
*Manning N:              Grid           Treynor_chan-n.rtg    [s/m^(1/3)]
*Bed width:              Grid           Treynor_chan-w.rtg  [m]
*Bank angle:             Grid           Treynor_chan-a.rtg  [deg]
*Init. depth:            Scalar         0.00000000          [m]
*Sinuosity:              Scalar         1.00000000          [m/m]]]
Input format ASCII, Binary
Other input format
Describe output parameters [[Describe output parameters model::The output variable entrees through the GUI will be the following:
   *Save grid timestep:     Scalar         60.00000000       [sec]
   *Save Q grids:           1              Case5_2D-Q.rts    [m^3/s]
   *Save u grids:           0              Case5_2D-u.rts    [m/s]
   *Save d grids:           0              Case5_2D-d.rts    [m]
   *Save f grids:           0              Case5_2D-f.rts    [none]
   *Save pixels timestep:   Scalar         60.00000000       [sec]
   *Save Q pixels:          1              Case5_0D-Q.txt    [m^3/s]
   *Save u pixels:          0              Case5_0D-u.txt    [m/s]
   *Save d pixels:          0              Case5_0D-d.txt    [m]
   *Save f pixels:          0              Case5_0D-f.txt    [none]]]
Output format ASCII, Binary
Other output format
Pre-processing software needed? Yes
Describe pre-processing software RiverTools or a similar program is helpful for pre- and post-processing.
Post-processing software needed? Yes
Describe post-processing software RiverTools or a similar program is helpful for pre- and post-processing.
Visualization software needed? No
If above answer is yes
Other visualization software


Process

Describe processes represented by the model Snowmelt (degree-day or energy balance), precipitation (measured or simulated), evapotranspiration (Priestley-Taylor or energy balance), infiltration (Green-Ampt, Smith-Parlange or Richards' 1D, multi-layer), overland flow, shallow subsurface flow (Darcy, up to 6 layers), flow diversions (sinks, sources or canals)
Describe key physical parameters and equations [[Describe key physical parameters::(Soucre: TopoFlow HTML Help System)
ΔV(i,t)=   Δt * [ R(i,t) Δx Δy - Q(i,t) + Σk Q(k,t) ] 	 = change in water volume [m3],   mass conservation
d 	=   {[ w2 + 4 tan(θ) V / L]1/2 - w } / [2 tan(θ)]   	= mean water depth in channel segment [m]   (if θ > 0)
d 	=   V / [w * L] 	= mean water depth in channel segment [m]   (if θ = 0)
Q 	=   v * Aw 	= discharge of water [m3 / s]
v 	=   n-1 * Rh2/3 * S1/2 	= section-averaged velocity [m / s], Manning's formula
v 	=   ( g * Rh * S)1/2 * LN( a * d / z0) / κ 	= section-averaged velocity [m / s], Law of the Wall
Rh 	=   Aw / Pw 	= hydraulic radius [m]
Aw 	=   d * [w + (d * tan(θ))] 	= wetted cross-sectional area of a trapezoid [m2]
Pw 	=   w + [2 * d / cos(θ)] 	= wetted perimeter of a trapezoid [m]
Vw 	=   d2 * [ L * tan(θ) ] + d * [L * w] 	= wetted volume of a trapezoidal channel [m]]]
Describe length scale and resolution constraints Recommended grid cell size is around 100 meters, but can be parameterized to run with a wide range of grid cell sizes. DEM grid dimensions are typically less than 1000 columns by 1000 rows.
Describe time scale and resolution constraints Each process can have its own timestep. Typical timesteps are: channel flow (seconds), infiltration (seconds to minutes), snowmelt (hours to days), subsurface flow (hours to days), etc. Model can be run for a full year or longer, if necessary.
Describe any numerical limitations and issues Diffusive wave routing routine needs more testing.


Testing

Describe available calibration data sets TopoFlow:Channels:Diffusive Wave is typically not calibrated to fit data, but is run with best guesses of the physical parameters.
Upload calibration data sets if available:
Describe available test data sets Available test datat sets:
   * Treynor watershed, in the Nishnabotna river basin, in Iowa, USA. Two large events.
   * Arctic watershed data from Larry Hinzman (UAF).
Upload test data sets if available:
Describe ideal data for testing Several test datasets can be downloaded from the TopoFlow website.


Other

Do you have current or future plans for collaborating with other researchers? Collaborators include: Larry Hinzman (UAF), Bob Bolton, Anna Liljedahl (UAF), Stefan Pohl, Tom Over and others
Is there a manual available? Yes
Upload manual if available:
Model website if any This site.
Model forum / discussion board
Comments The Numerical Python module (numpy) is used for fast, array-based processing. TopoFlow has a 90+ page HTML help system and intuitive GUI that is ideal for teaching.

Introduction

History

Papers

Issues

Help

Input Files

Output Files

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Source