GMS, SMS, and WMS User Forum

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1. ## SMS outputs: Velocity vs Water Depth Coverage

Forum friends, Could anyone possibly enlighten me on why in some of the elements i am registering a velocity but in those same elements there is no water depth? Shouldn't they be equal?
2. ## Sediment Transport Coefficients: Wilcock-Crowe

For those of you that happen upon a similar question that I had: Three parameters may be entered: T1, T2, D_sand. T1 and T2 are used to compute the reference Shields parameter THETA used in the Parker (1990) equation: THETA = T1+(T2-T1)*Exp(-20F_sand), where F_sand is the fraction of sediments on the bed surface finer than the diameter specified by D_sand in mm. The default values of the three are T1 = 0.021, T2 = 0.036, and D_sand = 1.0. This is a direct excerpt from Dr. Lai's current work on his sediment transport manual that will be coming out soon.
3. ## Sediment Transport Coefficients: Wilcock-Crowe

Hi all, I am in the midst of publishing a paper for a journal publication. To get right to the point, a reviewer asked me to differentiate between the Parker (1990) sed transport equation and the Wilcock-Crowe (2003) equation in the context of the model. The Parker coefficients have no shortage of explanations in most publications but The input coefficients for the Wilcock Crowe equation are less clear. They are listed as follows: Wilcock T1 coefficient = 0.021 Wilcock T2 coefficient = 0.036 Does anyone know what the "T1" and "T2" coefficients are related to? I checked the wiki and all it does is list these coefficients and gives no explanation. A google search also leaves me empty handed. Any direction would be greatly appreciated. thanks, Isaac
4. ## Exporting Results to a GIS?

Hey modeling gurus, I am at a part of the modeling where I would like to be able to export my results from the program into ArcMap so that I can preform a more comprehensive analysis. Because I am working with sediment transport I would like to be able to do some raster calculations with the original bathymetery and the post modeling bathymetery. Is there a way to pull the information out to do this type of analysis? Ive noticed in the results section that the Erosion Depth, for example, has three different export options: Binary, ASCII and XMDF. The first two options only contain a single line of text which doesnt seem particularly helpful and im not sure if the last option is useable . Any ideas would be greatly appreciated! thanks, Isaac
5. ## Sediment Materials Layer: How does Armoring Work?

"Armoring is part of the modeling results. For example, if 5 size classes are chosen, only the first 3 finer classes are eroded under certain conditions and the two coarser ones are not movable based on the selected sediment transportation equation." This quote was directly from Dr. Yong Lai (creater of the program) in an email I had sent to him. However, shortly after I ended up not needing to worry about this mechanism as we were able to obtain a singular representative gradation curve for the modeling site. Hope this may help any who come across this in the future!
6. ## Sediment Materials Layer: How does Armoring Work?

Hi all, Is anyone familiar with how armoring is represented in SRH-2D between two different sediment distributions? The Wiki help page hinted that the calculation is possible with the following statement but nothing more: "For gravel bed rivers the upper layer can represent a coarse surface armor and the deeper layer is the subsurface gradation" The armoring mechanism is an essential part to the river I am working with so I would be prefer to stay away from saying that it operates in a "black box". Any input on where to look or how it may work would be great! Thanks, Isaac
7. ## Creating New Hydrograph for segment of River

I've been running a handful of sediment transport sims but am finding some of them are taking much longer than I have time for. If you look at the attached image there are two defined channels that feed into my area of interest ( the trenches further down stream). Is there a tool that could be used to create two new hydrographs at these two inputs based on the singular hydrograph that originally filled the entire domain (figure also included) through these areas? My second question is then would this task in itself be worth the time? There is no specific tool I can see that may be of use here. My end goal is to reduce the number of elements, and therefore the domain size and hopefully see a significant decrease in simulation time.
8. ## Erosion Depth not additive between simulations?

I see what you mean. That might have been a bit of oversight on my part. I went ahead and set "irest=1" in the same file but I was prompted with the same error code as above which I could not troubleshoot. With what you have mentioned from the manual, I went ahead and gave the restart file another try for the next 1000 hours. I will let you know when it is completed to see whether or not the sediment info is carried over and then go from there. Thanks again for the input!
9. ## Erosion Depth not additive between simulations?

Thanks for the reply Cody. So I have found what I need to do to make the next simulation continue the sedimentation/erosion in a response from Dr. Lai. As opposed to inputting the RST.dat in the model control you write into the DIP.dat file from the previous simulation using "irest= ID" where ID is the # of the RST file from SRH-2D (Mine ended at RST43 so I input in the DIP.dat file "irest= 43"). However, when I then selected the DIP.dat file I had altered as the restart file, i got a strange error that Ive attached below that I cant find anything in the manual for. Any help with this would be very helpful.
10. ## Erosion Depth not additive between simulations?

Hi all, I am attempting to carry out a lengthy sediment transport scenario that's 2952 hours (yikes). To have a bit more control of the results I thought to run it in roughly 1000 hr intervals. When I finished the first interval I thought all that would be necessary to continue evaluating the rate of deposition/erosion would be selecting the restart file (RST.dat) from the end of the previous simulation to start the next one. However, it seems the deposition/erosion process is not additive looking at the results from the end of the second interval. Does the restart file not contain the erosion values needed for the next simulation? Or maybe there is something else besides the restart file that I need to make this work? thanks, Isaac
11. ## Persisting PreSRH-2D Error

No sooner do I post this that I find a solution. Forgot I needed at least two layers for the areas where I desire to evaluate deposition and erosion. However, since it has been executing the output from the quickwin is saying something strange while my two points haven't changed...
12. ## Persisting PreSRH-2D Error

Hi all, Ive been running into a bit of a problem with getting a sediment transport simulation to execute properly. I was able to get a hydrologic model running just fine but as soon as I introduced the sediment coverages and attempted to start a run I was road blocked by the errors in the images below. After exiting from the " Program Terminated Exit Code 0" window I was prompted by another message. That said the following --> ERROR: File not found:"MyCaseName_XMDF.h5". Any thoughts or direction? Ive tried going back to a previous save to no avail and also found a previous post about this on the forum suggesting the construction on a new identical BC coverage but that would take some time so I figured I would post this before starting that process. thanks, Isaac
13. ## Sediment Transport Problem

I found a somewhat stable solution so I should be fine for the near future.
14. ## Sediment Transport Problem

Hello, I've been working with the current version of SMS and SRH-2D for some time now but am running into a bit of difficulty trying to interpret the results for a sediment transport analysis. As a precursor to a full blown sediment transport model, I put together a proof of concept model that I drew up in AutoCAD to test what is known about the site. This is just so I can get more immediate results prior to modeling the actual test site, knowing the time it can take to run such a simulation. A quick Summary of the site: The river of interest has had a large sediment extraction, for a nearby road, in the form of a trench which is what the below figures represent. Recent field observations suggest that the front side of the trench is filling with sediment while the back side is scouring. The end goal of what I am doing is to provide some time scale in which it will be completely refilled again. Problem: Currently, I have the parameters such that after a simulation, deposition occurs within the trench but erosion from the backside seems to not occur, contrary to what has been reported. I have used a wide range of sediment sizes from 0.125 mm to 20 mm, a range of discharges from 20 cms to 100 cms and usually 48-72 hours to see any changes. As a side note, I have run through the sediment transport tutorials that are offered through Aquaveo and used the sediment parameters from those tutorials as a baseline for my model. Is there any general concerns I should have on drawings that I have imported and output results I get? Also, is anyone familiar with any ideas on input parameters that could produce what has been observed? I am running out of ideas myself so any new approach I could try would be greatly appreciated. I also apologize in advance as I have not tried to explain this to anyone in detail so if there is any other crucial information that may be telling of this situation, I can happily provide more details. thanks, Isaac
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