ALE - Time step decreased more than 50% redo cycle
Ahmet Feyzi Yildirim
I get the following error.
time step decreased more than 50% redo cycle 227
*** Warning 40117 (SOL+117)
negative vol in advection redo cycle 228
228 t 2.2527E-01 dt 5.17E-13 write d3plot file
Best Regards,
Ahmet YILDIRIM
l...@schwer.net
All ALE simulation should use a TSSFAC, see Control_Timestep, of 0.6 or less.
--len
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James Kennedy
Dear Ahmet.,
Len Schwer previously shared the following suggestions:
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Reducing the time step, via TSSFAC, or a *Define_Curve with prescribed time
step size, may help.
Before ever advection cycle, a Lagrange step is performed. If the time step is too
large, an element may invert (negative volume) and cause the error you received.
-----------------------
The message “negative volume in advection redo cycle” usually indicates the time
step needs to be reduced. Perhaps related to your use of mass scaling?
MM-ALE requires a smaller stable time step than that used for standard FEM solids,
so it is recommend to use TSSFAC=0.67 and NOT an increased time step via mass scaling
-----------------------
Sincerely,
James M. Kennedy
KBS2 Inc.
July 3, 2023
From: ls-d...@googlegroups.com [mailto:ls-d...@googlegroups.com] On Behalf Of Ahmet Feyzi Yildirim
Sent: Monday, July 03, 2023 7:43 AM
To: ls-d...@googlegroups.com
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