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buoyantPimpleFoam - no relaxation

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Old   January 14, 2014, 18:06
Default buoyantPimpleFoam - no relaxation
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Tobias Holzmann
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Hi all,

maybe I found a bug in the buoyantPimpleFoam solver.

Information:

  • small case (2D - wedged)
  • closed volume
  • T initialized with setFields
  • dt = 1e-8
  • save date all 1e-8 (so every iteration)


1. Step


  • No relaxation factors in fvSolution
  • I get 24 iterations
  • after that simulation blow up


2. Step


  • added relaxation to fvSolution
  • After 24 iterations the simulation blow up


3. Step


  • relax factors to 0.001
  • After 24 iterations the simulation blow up
  • Solution in paraview like Step 1 and 2


4. Step


  • relax factors changed to 1e5
  • After 24 iterations the simulation blow up
  • Solution in paraview like 1, 2 and 3




So in my opinion the relaxation factors are not taken into accout because if I set the factors to 1e5 I should never reach the second/third iteration, arent I ?



Additionally I had a look into the code - relaxation is included:
Code:
    EEqn.relax();
    pEqn.relax();
    UEqn.relax();

So now the question is, why I get always same solutions if I change the relaxation factors - thats not correct.

If I change the factors in simpleFoam to 100 the simulation blow up at the beginning.


Thanks in advance
Tobi
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Old   January 14, 2014, 18:14
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Tobias Holzmann
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Hi all,

sometimes people should go to bed if they are tierd.
The relaxation is working - I just made a mistake in the relaxation declaration with "Final" ...

@Mod - this thread can be deleted.
Thanks for reading and sorry for "spaming"


Regards Tobi
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