Model:Mrip

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Mrip




Metadata

Also known as
Model type Single
Model part of larger framework
Incorporated models or components:
Spatial dimensions 2D
Spatial extent Reach-Scale, Patch-Scale
Model domain Coastal, Hydrology
One-line model description Mrip is a self-organization type model for the formation and dynamics of megaripples in the nearshore.
Extended model description Mrip consists of a matrix representing the sea floor (25x25 m at this time). Blocks in the matrix are picked up (or deposited) according to transport rules or equations (users choice) and moved with the flow. The user-determined flow is altered, depending on the height and slope of the bed, thus creating feedback.
Keywords:

bedform evolution, nearshore,


First name Edith
Last name Gallagher
Type of contact Model developer
Institute / Organization Franklin and Marshall College
Postal address 1 PO Box 3003
Postal address 2
Town / City Lancaster
Postal code 17604-3003
State Pennsylvania
Country United States
Email address edith.gallagher@fandm.edu
Phone 717-291-4055
Fax 717-358-4548


Supported platforms Windows
Other platform
Programming language Matlab
Other program language
Code optimized Single Processor
Multiple processors implemented
Nr of distributed processors
Nr of shared processors
Start year development 2003
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 https://github.com/csdms-contrib/mrip
Program license type GPL v2
Program license type other
Memory requirements
Typical run time ~1 hr (depending on duration of simulation)


Describe input parameters Basic parameters for a sediment transport model (grain size, efficiency coefficients, coefficient of friction, wave friction factor, density, etc) most are in there using values from the literature, but easily modified.

Flow. (Sinusoidal, steady or combined flows can be created, as well as natural flow data can be used.) A random "turbulent" flow is imposed - this needs a magnitude. Jump fraction - given distance sediment moves with flow

Input format ASCII
Other input format
Describe output parameters Options (can be turned on or off):

Print evolving bed to screen. A file with the bed with each time step, or at intermediate steps. A file with the spectra of bed at each time step, or at intermediate steps. A file with statistics (eg, rms roughness of bed)

Output format ASCII
Other output format Matlab files
Pre-processing software needed? No
Describe pre-processing software
Post-processing software needed? No
Describe post-processing software
Visualization software needed? No
If above answer is yes
Other visualization software


Describe processes represented by the model The bed is represented by a 2-D matrix. At this time the bed is 250 x 250. Each block (i,j) is taken to be a slab of sediment 10cm x 10cm x 1cm deep.

A second matrix represents the flow. This is the same everywhere in the domain at each time point, except for a random spatial fluctuation representing turbulence.

The user-defined flow picks up (or puts down) sediment according to a transport law. Three transport laws have been tested: Bailard (1981), Ribberink (1998) or simple rules. The simple rules are simply thresholds: (if flow greater than 70cm/sec pick up one block).

Once sand block have been picked up, they are moved forward with the flow. Generally, I have used a fraction of the distance that the water would travel (jump_frac). So, with a flow of 100cm/sec, in one second that water goes 100 cm. The sand in this case would go 50 cm (half the distance). At the extremes, the model is sensitive to this parameter, but at intermediate values, it is not.

Tested flows have consisted of combined sinusoidal flow+steady flow, purely osc, purely steady, and natural flow time series taken from current meter measurements. All flows have a random spatial fluctuation added at each time point.

Once bedforms are generated, feedback rules are employed by altering the flow over the bedform. Once a bedform gets tall, the flow over the top accelerates, increasing transport at that location. In the steep lee of a bedform, a shadow zone forms where flow goes to ~zero, therefore transport goes to zero. These mechanisms destroy or build bedforms.

Describe key physical parameters and equations "Key" parameters:
  • the transport thresholds (if you use the simple rules) (it is cool, model results are similar with all the transport models that have been tested)
  • the flow magnitudes and turbulence magnitude
  • Jump_frac
  • all the little parameters in the transport equations

Most parameters act to speed or slow transport, which in turn speeds or slows the growth of bedforms.

Describe length scale and resolution constraints With Matlab running on my desktop PC I get out of memory errors when I make the domain much bigger than it is at present (250x250). I am working to expand the model domain. I would also like to increase the resolution. (Isn't this what all modelers want to do?)
Describe time scale and resolution constraints One second has been the time resolution. I haven't played with this.
Describe any numerical limitations and issues


Describe available calibration data sets The model has been compared qualitatively with Clarke and Werner (2004), Gallagher et al 1998, 2003 and 2005 and various Hay papers.
Upload calibration data sets if available:
Describe available test data sets
Upload test data sets if available:
Describe ideal data for testing


Do you have current or future plans for collaborating with other researchers? yes.
Is there a manual available? No
Upload manual if available:
Model website if any
Model forum / discussion board
Comments


This part will be filled out by CSDMS staff

OpenMI compliant No but possible
BMI compliant No but planned
WMT component No but possible
PyMT component
DOI model 10.1594/IEDA/100149
For model version 0.1
Year version submitted 2011
Link to file https://csdms.colorado.edu/pub/models/doi-source-code/mrip-10.1594.IEDA.100149-0.1.tar.gz
Can be coupled with:
Model info

Citation indices Mrip
Nr. of pubs: 1
Citations: 0
h-index: --"--" is not a number.
Qrcode Mrip.png
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Introduction

History

References




Citation indices Mrip
Nr. of pubs: 1
Citations: 0
h-index: --"--" is not a number.



Featured publication(s)YearModel describedType of ReferenceCitations
Gallagher, E.; 2011. Mrip, version 0.1.. , , https://csdms.colorado.edu/pub/models/doi-source-code/mrip-10.1594.IEDA.100149-0.1.tar.gz. 10.1594/IEDA/100149
(View/edit entry)
2011Mrip
Source code ref. --
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