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Bend model sediment thickness results

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Burhan Yildiz, modified 8 Months ago.

Bend model sediment thickness results

Keen Forecaster Posts: 7 Join Date: 8/7/20 Recent Posts
Hi everyone,
I used the bend model of the riverlab to run. Although I run the simulation for 20 days, no change on the sediment thickness is observed. Do you think this is the expected result or am I doing something wrong? (I used Delft3D v. 4.04.01)
Thanks in advance.Burhan.
Victor Chavarrias, modified 8 Months ago.

RE: Bend model sediment thickness results

Famous Fortune teller Posts: 48 Join Date: 4/24/20 Recent Posts
That is definitely not the expected result.
First thing to check: Is morphology on?
The mdf-file should have the lines:
Filsed = #sed.sed# 
Filmor = #mor.mor# 
The mor-file should have the line:
BedUpd           = true             
A second problem may be the time frame. The time unit of the simulation as downloaded is seconds (Tunit  = #S# in the mdu-file). If you have opened the simulation with the GUI, you will have seen that it only accepts minutes as time unit. If you have changed the unit to minutes, please check that all the times in the boundary conditions and the start time of morphodynamic changes is correct (parameter MorStt in the mor-file). 

A third problem may be plotting. How are you plotting? Are you plotting the bed elevation?              
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Burhan Yildiz, modified 8 Months ago.

RE: Bend model sediment thickness results

Keen Forecaster Posts: 7 Join Date: 8/7/20 Recent Posts
Thank you Victor for your reply. The solution lies in your third alternative. I used to select sediment thickness but bed level graphics show some bathymetry changes after 5 days. Well, do you think this is normal? In the first 5 days, there is exactly no change at the bed levels but starting from 7.5 days there is change in bed level.
Victor Chavarrias, modified 8 Months ago.

RE: Bend model sediment thickness results

Famous Fortune teller Posts: 48 Join Date: 4/24/20 Recent Posts
Check parameter MorStt in the mor-file. This parameter defines the time (in TUnit) before morphodynamic changes occur. This parameter is set to 7200. When the time unit is seconds, there is no bed level change in the first 2 h, which serves the purpose of obtaining steady state flow. If you have changed the TUnit to minutes, you will have no change in the first 7200/60/24=5 days. Furthermore, it seems you have also not adjusted the interval of the map output. Check parameter Flmap in the mdf-file. 
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Burhan Yildiz, modified 8 Months ago.

RE: Bend model sediment thickness results

Keen Forecaster Posts: 7 Join Date: 8/7/20 Recent Posts
I see.. Thank you for the replies.