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Summary Contact Technical specs In/Output Process Testing Other Component info Also known as Model type Single Incorporated models or components: Spatial dimensions 2D Spatial extent Landscape-Scale, Watershed-Scale Model domain One-line model description Kinematic Wave process component for flow routing in a D8-based, spatial hydrologic model. Extended model description This process component is part of a spatially-distributed hydrologic model called TopoFlow, but it can now be used as a stand-alone model. The kinematic wave method (Lighthill and Whitham, 1955) is the simplest method for modeling flow in open channels. This method combines mass conservation with the simplest possible treatment of momentum conservation, namely that all terms in the general momentum equation (pressure gradient, local acceleration and convective acceleration) are neglible except the friction and gravity terms. A flow in which gravitational acceleration is exactly balanced by friction is referred to as steady, uniform flow. For these flows the water surface slope, energy slope and bed slope are all equal. Keywords: basins, First name Scott Last name 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 Email address Scott.Peckham@colorado.edu Phone 303-492-6752 Fax Supported platforms Unix, Linux, Mac OS, Windows Other platform Programming language Python Other program language None (but uses NumPy package) 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? No If above answer is no, provide end year model development Model availability As code, As teaching tool Source code availability (Or provide future intension) Through CSDMS repository Source web address View source code http://csdms.colorado.edu/viewvc/topoflow/ Program license type Apache public license Program license type other Memory requirements Standard Typical run time Minutes to hours Describe input parameters The input variables used for the Dynamic Wave method of routing flow in channels are defined as follows. These inputs must be provided as grids: 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 / m^1/3) 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 Notes below) These inputs can be provided as scalars or grids: sinuosity = channel sinuosity (m/m) (along-channel / straight length) init_depth = initial water depth (m) (See HTML help) Grids must be saved in binary files with no header. All variables should be stored as 4-byte, floating-point numbers (IEEE standard) except flow codes, which are unsigned, 1-byte integers. The behavior of this component is controlled with a configuration (CFG) file, which may point to other files that contain input data. Here is a sample configuration (CFG) file for this component: Method code: 1 Method name: Kinematic_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) 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) Input format ASCII, Binary Other input format Describe output parameters This component computes the following variables, as grids: Q = discharge (m^3/s) u = flow velocity (m/s) d = flow depth (m) f = friction factor (none) Rh = hydraulic radius (m) S_free = free-surface slope (m/m) The user can choose which, if any, of these to save. Each may be saved as a grid sequence, indexed by time, in a netCDF file, at a specified sampling rate. Each may also be saved for a set of "monitored" grid cells, each specified as a (row,column) pair in a file with the name: <case_prefix>_outlets.txt. With this option, computed values are saved in a multi-column text file at a specified sampling rate. Each column in this file corresponds to a time series of values for a particular grid cell. For both options the sampling rate must no smaller than the process timestep. Output format ASCII, Binary Other output format Pre-processing software needed? Yes Describe pre-processing software Another program must be used to create the input grids. This includes a D8 flow grid derived from a DEM for the region to be modeled. The earlier, IDL version of TopoFlow can be used to create some of these. Post-processing software needed? Yes Describe post-processing software None, except visualization software. Grid sequences saved in netCDF files can be viewed as animations and saved as movies using VisIt. Visualization software needed? Yes If above answer is yes Other visualization software VisIt Describe processes represented by the model The kinematic wave method for flow routing in the channels of a D8-based river network. Describe key physical parameters and equations Main equations used by this component: ΔV(i,t) = Δt * ( R(i,t) Δx Δy - Q(i,t) + Σ_k Q(k,t) ) = change in water volume (m^3), mass conservation d = {( w^2 + 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 * A_w = discharge of water (m3 / s) v = n^-1 * R_h^2/3 * S^1/2 = section-averaged velocity (m / s), Manning's formula v = ( g * Rh * S)^1/2 * LN( a * d / z_0) / κ = section-averaged velocity (m / s), Law of the Wall R_h = A_w / P_w = hydraulic radius (m) A_w = d * (w + (d * tan(θ))) = wetted cross-sectional area of a trapezoid (m2) P_w = w + (2 * d / cos(θ)) = wetted perimeter of a trapezoid (m) V_w = d^2 * ( 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 The basic stability condition is: dt < (dx / u_min), where dt is the timestep, dx is the grid cell size and u_min is the smallest velocity in the grid. This ensures that flow cannot cross a grid cell in less than one time step. Typical timesteps are on the order of seconds to minutes. Model can be run for a full year or longer, if necessary. Describe any numerical limitations and issues This model/component needs more rigorous testing. Describe available calibration data sets This model/component is typically not calibrated to fit data, but is run with a best guess or measured value for each input parameter. Upload calibration data sets if available: Describe available test data sets Available test data sets: Treynor watershed, in the Nishnabotna River basin, Iowa, USA. (Two large rainfall events.) Small basin in Kentucky. Inclined plane for testing. Arctic watershed data from Larry Hinzman (UAF). See /data/progs/topoflow/3.0/data on CSDMS cluster. Upload test data sets if available: Describe ideal data for testing Several test datasets are stored on the CSDMS cluster at: /data/progs/topoflow/3.0/data. 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 Provide key papers on model if any Key Papers: Peckham, S.D., 2008. Geomorphometry and spatial hydrologic modeling (Chapter 25), In: Hengl, T. and Reuter, H.I. (Eds), Geomorphometry: Concepts, Software and Applications. Developments in Soil Science, vol. 33, Elsevier, 579-602 pp. Doi: (10.1016/S0166-2481(08)00025-1). Is there a manual available? Yes Upload manual if available: Model website if any This site. Model forum / discussion board Comments About this component: This component was developed as part of the TopoFlow hydrologic model, which was originally written in IDL and had a point-and-click GUI. For more information on TopoFlow, please goto: http://csdms.colorado.edu/wiki/Model:TopoFlow. When used from within the CSDMS Modeling Tool (CMT), this component has "config" button which launches a graphical user interface (GUI) for changing input parameters. The GUI is a tabbed dialog with a Help button at the bottom that displays HTML help in a browser window. This component also has a configuration (CFG) file, with a name of the form: <case_prefix>_channels_diff_wave.cfg. This file can be edited with a text editor. The Numerical Python module (numpy) is used for fast, array-based processing. This model has an OpenMI-style interface, similar to OpenMI 2.0. Part of this interface is inherited from "CSDMS_base.py". This part will be filled out by CSDMS staff OpenMI compliant No but planned CCA component Yes IRF interface Yes CMT compontent Yes Can be coupled with: TopoFlow, TopoFlow-Meteorology, TopoFlow-Snowmelt-Degree-Day, TopoFlow-Snowmelt-Energy_Balance, TopoFlow-Evaporation-Energy_Balance, TopoFlow-Evaporation-Priestley_Taylor, TopoFlow-Evaporation-Read_File, TopoFlow-Infiltration-Green-Ampt, TopoFlow-Infiltration-Richards_1D, TopoFlow-Infiltration-Smith-Parlange, TopoFlow-Saturated_Zone-Darcy_Law, Gc2d, TopoFlow-Diversions,

Model info Authors Scott Peckham Source code Download View source QR-code Link to this page Other models by this author Erode Erode-D8-Local Shoreline TopoFlow TopoFlow-Channels-Diffusive Wave TopoFlow-Channels-Dynamic Wave TopoFlow-Channels-Kinematic Wave TopoFlow-DEM Smoother TopoFlow-Data-HIS TopoFlow-Diversions … further results

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