Different types of cohesive sediments

Hi everyone, I’m simulating the cohesive sediment transport in the estuary.
At first, I used one type of sediment to simulate and got an acceptable calibration and validation.
Then I tried to use five types of sediment but same parameters for three upstream boundaries,one downstream boundary and sediment bed individually.
I found that two simulations had the different results,then why did it happen?
Thank you.

Thanks for your question about sediment transport simulations.

Yes, those two simulations should provide the same results, and our engineer team has also used the same modeling approach for several projects.

The different results could be due to the model input file setup, including initial conditions, boundary conditions, and sediment properties. It is not easy for us to give you a clear answer without seeing the model files.

It would be appreciated if you would thoroughly check the model input files from your end. If the issue is not resolved after checking the model input files, our team will find a way to support your solution. Thank you.



Dear Jeffrey
Thanks for your response.I think the model input files are the same.
I tried two types of cohesive sediment assigned for boundary and sediment bed. The results are still different. I’m not sure if the problem is due to sediment bed. I would appreciate it if you could help to find the solution.

Thanks for your checking with the model input files.

Sure, we will support addressing your concern. Would you send us the model input files via email (jfrjung@dsi.llc)? It would be helpful for us to examine the issue if we could receive the information, including:

  1. Input files of the two different models (e.g., one-sediment-class model vs two-sediment-class model)

  2. Version of EFDC+ executable file (e.g., EFDCPlus_MPI_10.3.10_SP64_220318.exe) used for this case

  3. Details about the different model results you are concerned about. It is not necessary to send us the model output files, instead, please let us know which results (e.g., bed delta, suspended sediment concentrations) are different between those two simulations. Screen captured images of the different model results would be much helpful.

It would be appreciated if you would provide the above information via email: jfrjung@dsi.llc

We commit to keeping your model data secure. Thank you.



Hello Jeffrey

I found that the problem might be the sediment bed input files are different(bedbdn.inp and bedddn.inp), so I would try more simulations to check it again. If it’s still not the solution, I’ll email you.

Thank you for spending time answering my questions.

Thank you for letting us know that.

I hope your models work well after modifying the sediment bed input files.

Please don’t hesitate to let us know if there is still a problem. Thank you.