CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > CFX

Sudden increase the residual of Maxwell's equations

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 13, 2016, 03:22
Post Sudden increase the residual of Maxwell's equations
  #1
New Member
 
Zhen
Join Date: Oct 2016
Posts: 4
Rep Power: 9
hsezsz is on a distinguished road
Hi guys,

I am simulating free burning arc in open air. My model can run the DC arc current of 5 kA and arcing time 10 ms. But for arc time 5 kA and 100 ms, it can run another 100 ms after the arcing time and then it crashes. After I check the out file, I find there is an sudden increase of the residual of Maxwell's equaions. It is understandable that after the arcing time, there is no more current input and any other energy input, therefore the Maxwell's equations will stops calculation gradually. To prevent the fault extrapolation, I add a step function to the current input to make sure that the current input stays 0 after the arcing time. I also changed the timestep from 1e-3 and 1e-4 but still crash at the same time. Does anyone have some solution for that? Thank you

Timestep: 1e-4

Adaptive Timestepping Information |
----------------------------------------------------------------------
| Direction | Ratio | Last Value | Next Value | RMS Co | Max Co |
+----------------+-------+------------+------------+--------+--------+
| Unchanged | 1.000 | 1.0000E-04 | 1.0000E-04 | 0.08 | 0.28 |
+----------------+-------+------------+------------+--------+--------+

================================================== ====================
TIME STEP = 4031 SIMULATION TIME = 2.0627E-01 CPU SECONDS = 1.015E+07
(THIS RUN: 1071 1.0139E-01 2.346E+06)
----------------------------------------------------------------------
COEFFICIENT LOOP ITERATION = 1 CPU SECONDS = 2.346E+06
----------------------------------------------------------------------
| Equation | Rate | RMS Res | Max Res | Linear Solution |
+----------------------+------+---------+---------+------------------+
| U-Mom | 0.89 | 6.9E-05 | 8.2E-04 | 4.7E-01 ok|
| V-Mom | 0.92 | 6.7E-05 | 1.1E-03 | 4.8E-01 ok|
| W-Mom | 0.85 | 1.9E-04 | 8.8E-04 | 4.7E-01 ok|
| P-Mass | 1.00 | 2.1E-03 | 1.6E-02 | 12.5 7.3E-02 OK|
+----------------------+------+---------+---------+------------------+
| Ax-Mag-Fluid Domain | 0.00 | 5.4-137 | 5.4E-70 | 0.0E+00 OK|
| Ay-Mag-Fluid Domain | 0.00 | 7.8-137 | 8.7E-70 | 0.0E+00 OK|
| Az-Mag-Fluid Domain | 0.00 | 1.4-136 | 8.5E-70 | 0.0E+00 OK|
| Ax-Mag-Solid Domain | 0.00 | 1.5-136 | 1.1E-69 | 0.0E+00 OK|
| Ay-Mag-Solid Domain | 0.00 | 2.1-136 | 1.2E-69 | 0.0E+00 OK|
| Az-Mag-Solid Domain | 0.00 | 2.7-136 | 1.2E-69 | 0.0E+00 OK|
| Ax-Mag-Solid Domain | 0.00 | 3.6E-72 | 4.1E-71 | 0.0E+00 OK|
| Ay-Mag-Solid Domain | 0.00 | 5.0E-72 | 6.8E-71 | 0.0E+00 OK|
| Az-Mag-Solid Domain | 0.00 | 2.3E-71 | 2.5E-70 | 5.2 0.0E+00 OK|
+----------------------+------+---------+---------+------------------+
| E-Pot-Fluid Domain | 0.00 | 2.3E-91 | 1.7E-89 | 0.0E+00 OK|
| E-Pot-Solid Domain E | 0.00 | 9.1-105 | 1.8-103 | 0.0E+00 OK|
| E-Pot-Solid Domain E | 0.00 | 2.1-106 | 4.5-105 | 5.4 0.0E+00 OK|
+----------------------+------+---------+---------+------------------+
| H-Energy | 1.00 | 4.7E-04 | 7.0E-03 | 2.4E-05 OK|
| T-Energy-Solid Domai | 1.00 | 1.2E-05 | 4.1E-04 | 2.4E-05 OK|
| T-Energy-Solid Domai | 1.00 | 5.5E-05 | 3.3E-04 | 5.5 2.4E-05 OK|
+----------------------+------+---------+---------+------------------+
| K-TurbKE | 1.00 | 2.5E-04 | 2.7E-03 | 5.5 4.1E-05 OK|
| E-Diss.K | 1.00 | 5.0E-05 | 1.2E-03 | 10.5 5.9E-07 OK|
+----------------------+------+---------+---------+------------------+
----------------------------------------------------------------------
COEFFICIENT LOOP ITERATION = 2 CPU SECONDS = 2.346E+06
----------------------------------------------------------------------
| Equation | Rate | RMS Res | Max Res | Linear Solution |
+----------------------+------+---------+---------+------------------+
| U-Mom | 1.35 | 9.3E-05 | 2.6E-03 | 5.5E-01 ok|
| V-Mom | 1.35 | 9.0E-05 | 2.3E-03 | 5.8E-01 ok|
| W-Mom | 0.51 | 9.8E-05 | 3.6E-03 | 5.2E-01 ok|
| P-Mass | 2.70 | 5.7E-03 | 5.6E-02 | 12.5 7.6E-02 OK|
+----------------------+------+---------+---------+------------------+
| Ax-Mag-Fluid Domain | 0.00 | 2.0-134 | 8.8E-69 | 0.0E+00 OK|
| Ay-Mag-Fluid Domain | 0.00 | 2.2-134 | 1.3E-68 | 0.0E+00 OK|
| Az-Mag-Fluid Domain | 0.00 | 6.9-134 | 1.6E-68 | 0.0E+00 OK|
| Ax-Mag-Solid Domain | 0.00 | 1.7-134 | 3.4E-69 | 0.0E+00 OK|
| Ay-Mag-Solid Domain | 0.00 | 2.2-134 | 6.8E-69 | 0.0E+00 OK|
| Az-Mag-Solid Domain | 0.00 | 2.6-134 | 6.6E-69 | 0.0E+00 OK|
| Ax-Mag-Solid Domain | 0.00 | 2.1E-71 | 1.3E-70 | 0.0E+00 OK|
| Ay-Mag-Solid Domain | 0.00 | 2.8E-71 | 1.7E-70 | 0.0E+00 OK|
| Az-Mag-Solid Domain | 0.00 | 1.9E-70 | 8.7E-70 | 5.2 0.0E+00 OK|
+----------------------+------+---------+---------+------------------+
| E-Pot-Fluid Domain | 0.00 | 8.2E-78 | 7.6E-76 | 0.0E+00 OK|
| E-Pot-Solid Domain E | 0.00 | 6.2E-91 | 4.4E-90 | 0.0E+00 OK|
| E-Pot-Solid Domain E | 0.00 | 6.6E-78 | 7.7E-77 | 5.4 0.0E+00 OK|
+----------------------+------+---------+---------+------------------+
| H-Energy | 0.31 | 1.5E-04 | 6.1E-03 | 1.1E-05 OK|
| T-Energy-Solid Domai | 0.50 | 5.8E-06 | 2.0E-04 | 1.1E-05 OK|
| T-Energy-Solid Domai | 0.50 | 2.7E-05 | 1.6E-04 | 5.5 1.1E-05 OK|
+----------------------+------+---------+---------+------------------+
| K-TurbKE | 0.49 | 1.3E-04 | 2.7E-03 | 5.5 3.0E-05 OK|
| E-Diss.K | 1.24 | 6.2E-05 | 2.3E-03 | 10.5 1.7E-06 OK|
+----------------------+------+---------+---------+------------------+
----------------------------------------------------------------------
COEFFICIENT LOOP ITERATION = 3 CPU SECONDS = 2.347E+06
----------------------------------------------------------------------
| Equation | Rate | RMS Res | Max Res | Linear Solution |
+----------------------+------+---------+---------+------------------+
| U-Mom | 0.94 | 8.7E-05 | 2.3E-03 | 2.9E-01 ok|
| V-Mom | 1.07 | 9.7E-05 | 3.4E-03 | 2.8E-01 ok|
| W-Mom | 0.95 | 9.4E-05 | 4.7E-03 | 2.5E-01 ok|
| P-Mass | 0.62 | 3.5E-03 | 6.4E-02 | 12.5 6.0E-02 OK|
+----------------------+------+---------+---------+------------------+
| Ax-Mag-Fluid Domain | 0.00 | 3.8E-02 | 1.5E-02 | 3.9E-02 OK|
| Ay-Mag-Fluid Domain | 0.00 | 4.1E-02 | 2.1E-02 | 5.8E-02 OK|
| Az-Mag-Fluid Domain | 0.00 | 7.0E-02 | 2.7E-02 | 7.8E-02 OK|
| Ax-Mag-Solid Domain | 0.00 | 2.4E-02 | 7.0E-03 | 3.9E-02 OK|
| Ay-Mag-Solid Domain | 0.00 | 3.1E-02 | 1.1E-02 | 5.8E-02 OK|
| Az-Mag-Solid Domain | 0.00 | 2.9E-02 | 8.7E-03 | 7.8E-02 OK|
| Ax-Mag-Solid Domain | 0.00 | 5.4E-05 | 5.6E-04 | 3.9E-02 OK|
| Ay-Mag-Solid Domain | 0.00 | 6.9E-05 | 5.8E-04 | 5.8E-02 OK|
| Az-Mag-Solid Domain | 0.00 | 6.4E-04 | 2.4E-03 | 30.5 7.8E-02 OK|
+----------------------+------+---------+---------+------------------+

+--------------------------------------------------------------------+
| ERROR #004100018 has occurred in subroutine FINMES. |
| Message: |
| Fatal overflow in linear solver. |
+--------------------------------------------------------------------+

+--------------------------------------------------------------------+
| An error has occurred in cfx5solve: |
| |
| The ANSYS CFX solver could not be started, or exited with return |
| code 255. No results file has been created. |
+--------------------------------------------------------------------+


Timestep:1e-3
Adaptive Timestepping Information |
----------------------------------------------------------------------
| Direction | Ratio | Last Value | Next Value | RMS Co | Max Co |
+----------------+-------+------------+------------+--------+--------+
| Decreasing | 0.800 | 1.0000E-03 | 8.0000E-04 | 0.85 | 2.88 |
+----------------+-------+------------+------------+--------+--------+

================================================== ====================
TIME STEP = 3158 SIMULATION TIME = 2.0626E-01 CPU SECONDS = 8.342E+06
(THIS RUN: 198 1.0138E-01 5.335E+05)
----------------------------------------------------------------------
COEFFICIENT LOOP ITERATION = 1 CPU SECONDS = 5.335E+05
----------------------------------------------------------------------
| Equation | Rate | RMS Res | Max Res | Linear Solution |
+----------------------+------+---------+---------+------------------+
| U-Mom | 1.01 | 2.4E-04 | 4.2E-03 | 8.8E-02 OK|
| V-Mom | 0.95 | 2.4E-04 | 2.8E-03 | 8.2E-02 OK|
| W-Mom | 1.22 | 5.6E-04 | 2.4E-03 | 6.7E-02 OK|
| P-Mass | 0.96 | 6.6E-04 | 4.5E-03 | 31.6 8.1E-02 OK|
+----------------------+------+---------+---------+------------------+
| Ax-Mag-Fluid Domain | 0.00 | 2.0E-02 | 7.4E-03 | 2.6E-02 OK|
| Ay-Mag-Fluid Domain | 0.00 | 1.7E-02 | 8.4E-03 | 4.3E-02 OK|
| Az-Mag-Fluid Domain | 0.00 | 8.3E-02 | 1.1E-02 | 9.3E-02 OK|
| Ax-Mag-Solid Domain | 0.00 | 6.6E-03 | 3.9E-03 | 2.6E-02 OK|
| Ay-Mag-Solid Domain | 0.00 | 1.4E-02 | 7.7E-03 | 4.3E-02 OK|
| Az-Mag-Solid Domain | 0.00 | 1.9E-02 | 8.2E-03 | 9.3E-02 OK|
| Ax-Mag-Solid Domain | 0.00 | 8.1E-05 | 6.2E-04 | 2.6E-02 OK|
| Ay-Mag-Solid Domain | 0.00 | 7.7E-05 | 6.2E-04 | 4.3E-02 OK|
| Az-Mag-Solid Domain | 0.00 | 5.1E-04 | 2.3E-03 | 34.7 9.3E-02 OK|
+----------------------+------+---------+---------+------------------+
| E-Pot-Fluid Domain | 0.00 | 2.7E-04 | 2.5E-02 | 6.0E+00 F |
| E-Pot-Solid Domain E | 0.00 | 1.4E-17 | 1.0E-16 | 6.0E+00 F |
| E-Pot-Solid Domain E | 0.00 | 7.9E-05 | 6.0E-04 | 14.3 6.0E+00 F |
+----------------------+------+---------+---------+------------------+
| H-Energy | 0.99 | 2.1E-03 | 5.7E-02 | 2.2E-03 OK|
| T-Energy-Solid Domai | 0.87 | 9.9E-05 | 3.5E-03 | 2.2E-03 OK|
| T-Energy-Solid Domai | 0.89 | 4.2E-04 | 2.6E-03 | 5.5 2.2E-03 OK|
+----------------------+------+---------+---------+------------------+
| K-TurbKE | 0.98 | 9.7E-04 | 1.6E-02 | 5.5 4.7E-03 OK|
| E-Diss.K | 0.89 | 1.3E-03 | 6.3E-02 | 10.6 1.2E-03 OK|
+----------------------+------+---------+---------+------------------+
----------------------------------------------------------------------
COEFFICIENT LOOP ITERATION = 2 CPU SECONDS = 5.338E+05
----------------------------------------------------------------------
| Equation | Rate | RMS Res | Max Res | Linear Solution |
+----------------------+------+---------+---------+------------------+
| U-Mom | 1.56 | 3.8E-04 | 1.7E-02 | 1.2E-01 ok|
| V-Mom | 1.61 | 3.8E-04 | 1.8E-02 | 1.1E-01 ok|
| W-Mom | 0.79 | 4.4E-04 | 1.5E-02 | 7.2E-02 OK|
| P-Mass | 1.09 | 7.2E-04 | 1.3E-02 | 16.3 9.8E-02 OK|
+----------------------+------+---------+---------+------------------+
| Ax-Mag-Fluid Domain | 0.95 | 1.9E-02 | 7.4E-03 | 2.4E-02 OK|
| Ay-Mag-Fluid Domain | 1.00 | 1.7E-02 | 9.5E-03 | 4.5E-02 OK|
| Az-Mag-Fluid Domain | 1.21 | 1.0E-01 | 1.2E-02 | 8.8E-02 OK|
| Ax-Mag-Solid Domain | 1.27 | 8.3E-03 | 3.0E-03 | 2.4E-02 OK|
| Ay-Mag-Solid Domain | 0.95 | 1.3E-02 | 6.3E-03 | 4.5E-02 OK|
| Az-Mag-Solid Domain | 0.73 | 1.4E-02 | 4.9E-03 | 8.8E-02 OK|
| Ax-Mag-Solid Domain | 1.02 | 8.3E-05 | 6.7E-04 | 2.4E-02 OK|
| Ay-Mag-Solid Domain | 0.92 | 7.1E-05 | 6.1E-04 | 4.5E-02 OK|
| Az-Mag-Solid Domain | 0.87 | 4.4E-04 | 2.3E-03 | 38.9 8.8E-02 OK|
+----------------------+------+---------+---------+------------------+

+--------------------------------------------------------------------+
| ERROR #004100018 has occurred in subroutine FINMES. |
| Message: |
| Fatal overflow in linear solver. |
+--------------------------------------------------------------------+

+--------------------------------------------------------------------+
| An error has occurred in cfx5solve: |
| |
| The ANSYS CFX solver exited with return code 2. No results file |
| has been created. |
+--------------------------------------------------------------------+

End of solution stage.
hsezsz is offline   Reply With Quote

Old   October 13, 2016, 05:34
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,731
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
Have you tried the general tips in the FAQ? http://www.cfd-online.com/Wiki/Ansys...do_about_it.3F
ghorrocks is offline   Reply With Quote

Old   October 13, 2016, 06:58
Default
  #3
New Member
 
Zhen
Join Date: Oct 2016
Posts: 4
Rep Power: 9
hsezsz is on a distinguished road
Yes, but I don't think the link provide useful information in my case. Thank you for the link!
hsezsz is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
time step continuity problem in VAWT simulation lpz_michele OpenFOAM Running, Solving & CFD 5 February 22, 2018 19:50
simpleFoam error - "Floating point exception" mbcx4jc2 OpenFOAM Running, Solving & CFD 12 August 4, 2015 02:20
Unstabil Simulation with chtMultiRegionFoam mbay101 OpenFOAM Running, Solving & CFD 13 December 28, 2013 13:12
How to write k and epsilon before the abnormal end xiuying OpenFOAM Running, Solving & CFD 8 August 27, 2013 15:33
Orifice Plate with a fully developed flow - Problems with convergence jonmec OpenFOAM Running, Solving & CFD 3 July 28, 2011 05:24


All times are GMT -4. The time now is 20:23.