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Very Low deltaT after just few iterations

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Old   June 19, 2020, 09:41
Default Very Low deltaT after just few iterations
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Hi everybody,
I'm running a simulation with pimpleDyMFoam and turbulence model kEpsilon, after just a few iterations deltaT drops to very low values (order of e-20) and a very high y+ value (order of e18). I cannot understand if the problem are the mesh and BC or the set up of schemes, solution and controlDict. Here attached fvSchemes, fvSolution and controlDict.
Thanks in advance.
Attached Files
File Type: txt controlDict.txt (2.0 KB, 2 views)
File Type: txt fvSchemes.txt (1.5 KB, 1 views)
File Type: txt fvSolution.txt (1.8 KB, 1 views)
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Old   June 23, 2020, 00:23
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raphael
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In your controlDict you have adjustTimeStep yes;
And maxCo 1;
So deltaT will drop until it reaches the constraint maxCo < 1

At the moment you could change adjustTimeStep to no.

We don't have enough info to help you more. You could run some iteration and have a check on paraview to see where the problem is located. You are looking for high-velocity cells.
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Old   June 23, 2020, 12:39
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Problem solved, the main issue was inconsistency between mesh and turbulence model adopted, thank you anyway
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Old   December 28, 2023, 04:09
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Quote:
Originally Posted by filippo222 View Post
Problem solved, the main issue was inconsistency between mesh and turbulence model adopted, thank you anyway

How do you know that the problem was inconsistency between mesh and turbulence? I have same the problem when I use pimpleFoam as solver for simulation of underwater vessel
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