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-   -   Two WAY FSI error (http://www.cfd-online.com/Forums/cfx/116984-two-way-fsi-error.html)

kish April 30, 2013 01:58

Two WAY FSI error
 
Dear all

I am doing two way fsi problem in a artery. I have given 3 cardiac cycles for my simulation Each cycles consists of 160 time steps. The simulation was running for 2 cardiac cycles normally with out any error. The CFX solver gives an error after 420 time steps.

Can you please give your feedback, why the solver return with error?

Thank you


Regards

Kish

Lance April 30, 2013 02:28

How can we possibly help you when you dont tell us what the error message is? Read:
http://www.cfd-online.com/Wiki/Ansys...ible_answer.3F

kish April 30, 2013 09:01

Quote:

Originally Posted by Lance (Post 424067)
How can we possibly help you when you dont tell us what the error message is? Read:
http://www.cfd-online.com/Wiki/Ansys...ible_answer.3F

Dear Mr Lance

Sorry for that.

the following is a error message

+--------------------------------------------------------------------+
| ERROR #002100061 has occurred in subroutine SERVE_CLIENTS. |
| Message: |
| The connection between this CFX process and an external process |
| has died unexpectedly. The following error was received: |
| External process : ANSYS |
| Error experienced : Read |
| |
| ** This error is fatal: Terminating ANSYS CFX Solver execution ** |
| Please review the output, error and log files from both the CFX |
| and external processes to determine the cause of the error. |
+--------------------------------------------------------------------+

+--------------------------------------------------------------------+
| An error has occurred in cfx5solve: |
| |
| The ANSYS CFX solver exited with return code 1. No results file |
| has been created. |
+--------------------------------------------------------------------+

End of solution stage.

+--------------------------------------------------------------------+
| The following transient and backup files written by the ANSYS CFX |
| solver have been saved in the directory D:/GUIDE WIRE 2 WAY FSI |
| PROBLEM/Non linear FSI study3/Non linear FSI study |
| 3_pending_tasks/dp0_CFX 1_Solution_1/Fluid Flow CFX_001: |
| |
| 9_CS.trn, 99_CS.trn, 98_CS.trn, 97_CS.trn, 96_CS.trn, 95_CS.trn, |
| 94_CS.trn, 93_CS.trn, 92_CS.trn, 91_CS.trn, 90_CS.trn, 8_CS.trn, |
| 89_CS.trn, 88_CS.trn, 87_CS.trn, 86_CS.trn, 85_CS.trn, 84_CS.trn, |
| 83_CS.trn, 82_CS.trn, 81_CS.trn, 80_CS.trn, 7_CS.trn, 79_CS.trn, |
| 78_CS.trn, 77_CS.trn, 76_CS.trn, 75_CS.trn, 74_CS.trn, 73_CS.trn, |
| 72_CS.trn, 71_CS.trn, 70_CS.trn, 6_CS.trn, 69_CS.trn, 68_CS.trn, |
| 67_CS.trn, 66_CS.trn, 65_CS.trn, 64_CS.trn, 63_CS.trn, 62_CS.trn, |
| 61_CS.trn, 60_CS.trn, 5_CS.trn, 59_CS.trn, 58_CS.trn, 57_CS.trn, |
| 56_CS.trn, 55_CS.trn, 54_CS.trn, 53_CS.trn, 52_CS.trn, 51_CS.trn, |
| 50_CS.trn, 4_CS.trn, 49_CS.trn, 48_CS.trn, 47_CS.trn, 46_CS.trn, |
| 45_CS.trn, 44_CS.trn, 43_CS.trn, 42_CS.trn, 427_CS.trn, |
| 426_CS.trn, 425_CS.trn, 424_CS.trn, 423_CS.trn, 422_CS.trn, |
| 421_CS.trn, 420_CS.trn, 41_CS.trn, 419_CS.trn, 418_CS.trn, |
| 417_CS.trn, 416_CS.trn, 415_CS.trn, 414_CS.trn, 413_CS.trn, |
| 412_CS.trn, 411_CS.trn, 410_CS.trn, 40_CS.trn, 409_CS.trn, |
| 408_CS.trn, 407_CS.trn, 406_CS.trn, 405_CS.trn, 404_CS.trn, |
| 403_CS.trn, 402_CS.trn, 401_CS.trn, 400_CS.trn, 3_CS.trn, |
| 39_CS.trn, 399_CS.trn, 398_CS.trn, 397_CS.trn, 396_CS.trn, |
| 395_CS.trn, 394_CS.trn, 393_CS.trn, 392_CS.trn, 391_CS.trn, |
| 390_CS.trn, 38_CS.trn, 389_CS.trn, 388_CS.trn, 387_CS.trn, |
| 386_CS.trn, 385_CS.trn, 384_CS.trn, 383_CS.trn, 382_CS.trn, |
| 381_CS.trn, 380_CS.trn, 37_CS.trn, 379_CS.trn, 378_CS.trn, |
| 377_CS.trn, 376_CS.trn, 375_CS.trn, 374_CS.trn, 373_CS.trn, |
| 372_CS.trn, 371_CS.trn, 370_CS.trn, 36_CS.trn, 369_CS.trn, |
| 368_CS.trn, 367_CS.trn, 366_CS.trn, 365_CS.trn, 364_CS.trn, |
| 363_CS.trn, 362_CS.trn, 361_CS.trn, 360_CS.trn, 35_CS.trn, |
| 359_CS.trn, 358_CS.trn, 357_CS.trn, 356_CS.trn, 355_CS.trn, |
| 354_CS.trn, 353_CS.trn, 352_CS.trn, 351_CS.trn, 350_CS.trn, |
| 34_CS.trn, 349_CS.trn, 348_CS.trn, 347_CS.trn, 346_CS.trn, |
| 345_CS.trn, 344_CS.trn, 343_CS.trn, 342_CS.trn, 341_CS.trn, |
| 340_CS.trn, 33_CS.trn, 339_CS.trn, 338_CS.trn, 337_CS.trn, |
| 336_CS.trn, 335_CS.trn, 334_CS.trn, 333_CS.trn, 332_CS.trn, |
| 331_CS.trn, 330_CS.trn, 32_CS.trn, 329_CS.trn, 328_CS.trn, |
| 327_CS.trn, 326_CS.trn, 325_CS.trn, 324_CS.trn, 323_CS.trn, |
| 322_CS.trn, 321_CS.trn, 320_CS.trn, 31_CS.trn, 319_CS.trn, |
| 318_CS.trn, 317_CS.trn, 316_CS.trn, 315_CS.trn, 314_CS.trn, |
| 313_CS.trn, 312_CS.trn, 311_CS.trn, 310_CS.trn, 30_CS.trn, |
| 309_CS.trn, 308_CS.trn, 307_CS.trn, 306_CS.trn, 305_CS.trn, |
| 304_CS.trn, 303_CS.trn, 302_CS.trn, 301_CS.trn, 300_CS.trn, |
| 2_CS.trn, 29_CS.trn, 299_CS.trn, 298_CS.trn, 297_CS.trn, |
| 296_CS.trn, 295_CS.trn, 294_CS.trn, 293_CS.trn, 292_CS.trn, |
| 291_CS.trn, 290_CS.trn, 28_CS.trn, 289_CS.trn, 288_CS.trn, |
| 287_CS.trn, 286_CS.trn, 285_CS.trn, 284_CS.trn, 283_CS.trn, |
| 282_CS.trn, 281_CS.trn, 280_CS.trn, 27_CS.trn, 279_CS.trn, |
| 278_CS.trn, 277_CS.trn, 276_CS.trn, 275_CS.trn, 274_CS.trn, |
| 273_CS.trn, 272_CS.trn, 271_CS.trn, 270_CS.trn, 26_CS.trn, |
| 269_CS.trn, 268_CS.trn, 267_CS.trn, 266_CS.trn, 265_CS.trn, |
| 264_CS.trn, 263_CS.trn, 262_CS.trn, 261_CS.trn, 260_CS.trn, |
| 25_CS.trn, 259_CS.trn, 258_CS.trn, 257_CS.trn, 256_CS.trn, |
| 255_CS.trn, 254_CS.trn, 253_CS.trn, 252_CS.trn, 251_CS.trn, |
| 250_CS.trn, 24_CS.trn, 249_CS.trn, 248_CS.trn, 247_CS.trn, |
| 246_CS.trn, 245_CS.trn, 244_CS.trn, 243_CS.trn, 242_CS.trn, |
| 241_CS.trn, 240_CS.trn, 23_CS.trn, 239_CS.trn, 238_CS.trn, |
| 237_CS.trn, 236_CS.trn, 235_CS.trn, 234_CS.trn, 233_CS.trn, |
| 232_CS.trn, 231_CS.trn, 230_CS.trn, 22_CS.trn, 229_CS.trn, |
| 228_CS.trn, 227_CS.trn, 226_CS.trn, 225_CS.trn, 224_CS.trn, |
| 223_CS.trn, 222_CS.trn, 221_CS.trn, 220_CS.trn, 21_CS.trn, |
| 219_CS.trn, 218_CS.trn, 217_CS.trn, 216_CS.trn, 215_CS.trn, |
| 214_CS.trn, 213_CS.trn, 212_CS.trn, 211_CS.trn, 210_CS.trn, |
| 20_CS.trn, 209_CS.trn, 208_CS.trn, 207_CS.trn, 206_CS.trn, |
| 205_CS.trn, 204_CS.trn, 203_CS.trn, 202_CS.trn, 201_CS.trn, |
| 200_CS.trn, 1_CS.trn, 19_CS.trn, 199_CS.trn, 198_CS.trn, |
| 197_CS.trn, 196_CS.trn, 195_CS.trn, 194_CS.trn, 193_CS.trn, |
| 192_CS.trn, 191_CS.trn, 190_CS.trn, 18_CS.trn, 189_CS.trn, |
| 188_CS.trn, 187_CS.trn, 186_CS.trn, 185_CS.trn, 184_CS.trn, |
| 183_CS.trn, 182_CS.trn, 181_CS.trn, 180_CS.trn, 17_CS.trn, |
| 179_CS.trn, 178_CS.trn, 177_CS.trn, 176_CS.trn, 175_CS.trn, |
| 174_CS.trn, 173_CS.trn, 172_CS.trn, 171_CS.trn, 170_CS.trn, |
| 16_CS.trn, 169_CS.trn, 168_CS.trn, 167_CS.trn, 166_CS.trn, |
| 165_CS.trn, 164_CS.trn, 163_CS.trn, 162_CS.trn, 161_CS.trn, |
| 160_CS.trn, 15_CS.trn, 159_CS.trn, 158_CS.trn, 157_CS.trn, |
| 156_CS.trn, 155_CS.trn, 154_CS.trn, 153_CS.trn, 152_CS.trn, |
| 151_CS.trn, 150_CS.trn, 14_CS.trn, 149_CS.trn, 148_CS.trn, |
| 147_CS.trn, 146_CS.trn, 145_CS.trn, 144_CS.trn, 143_CS.trn, |
| 142_CS.trn, 141_CS.trn, 140_CS.trn, 13_CS.trn, 139_CS.trn, |
| 138_CS.trn, 137_CS.trn, 136_CS.trn, 135_CS.trn, 134_CS.trn, |
| 133_CS.trn, 132_CS.trn, 131_CS.trn, 130_CS.trn, 12_CS.trn, |
| 129_CS.trn, 128_CS.trn, 127_CS.trn, 126_CS.trn, 125_CS.trn, |
| 124_CS.trn, 123_CS.trn, 122_CS.trn, 121_CS.trn, 120_CS.trn, |
| 11_CS.trn, 119_CS.trn, 118_CS.trn, 117_CS.trn, 116_CS.trn, |
| 115_CS.trn, 114_CS.trn, 113_CS.trn, 112_CS.trn, 111_CS.trn, |
| 110_CS.trn, 10_CS.trn, 109_CS.trn, 108_CS.trn, 107_CS.trn, |
| 106_CS.trn, 105_CS.trn, 104_CS.trn, 103_CS.trn, 102_CS.trn, |
| 101_CS.trn, 100_CS.trn, 0_CS.trn |
+--------------------------------------------------------------------+


+--------------------------------------------------------------------+
| An error has occurred in cfx5solve: |
| |
| ANSYS Solver terminated with return code 256 |
+--------------------------------------------------------------------+


+--------------------------------------------------------------------+
| The results from this run of the ANSYS solver have been written to |
| D:\GUIDE WIRE 2 WAY FSI PROBLEM\Non linear FSI study3\Non linear |
| FSI study 3_pending_tasks\dp0_CFX 1_Solution_1\Fluid Flow |
| CFX_001.ansys |
+--------------------------------------------------------------------+


+--------------------------------------------------------------------+
| The following user files have been saved in the directory D:/GUIDE |
| WIRE 2 WAY FSI PROBLEM/Non linear FSI study3/Non linear FSI study |
| 3_pending_tasks/dp0_CFX 1_Solution_1/Fluid Flow CFX_001: |
| |
| mon |
+--------------------------------------------------------------------+


+--------------------------------------------------------------------+
| Warning! |
| |
| After waiting for 60 seconds, 2 solver manager process(es) appear |
| not to have noticed that this run has ended. You may get errors |
| removing some files if they are still open in the solver manager. |
+--------------------------------------------------------------------+


This run of the ANSYS CFX Solver has finished.





The follwing is the ANSYS outfile
L O A D S T E P O P T I O N S

LOAD STEP NUMBER. . . . . . . . . . . . . . . . 428
TIME AT END OF THE LOAD STEP. . . . . . . . . . 2.1400
TIME STEP SIZE. . . . . . . . . . . . . . . . . 0.50000E-02
MAXIMUM NUMBER OF EQUILIBRIUM ITERATIONS. . . . 15
NONLINEAR STABILIZATION . . . . . . . . . . . .ON (CONSTANT)
STEP CHANGE BOUNDARY CONDITIONS . . . . . . . . YES
STRESS-STIFFENING . . . . . . . . . . . . . . . ON
TRANSIENT (INERTIA) EFFECTS
STRUCTURAL DOFS. . . . . . . . . . . . . . . ON
TRANSIENT INTEGRATION PARAMETERS
GAMMA. . . . . . . . . . . . . . . . . . . . 0.10000
ALPHA. . . . . . . . . . . . . . . . . . . . 0.30250
DELTA. . . . . . . . . . . . . . . . . . . . 0.60000
USING HHT TIME INTEGRATION
ALPHAF . . . . . . . . . . . . . . . . . . . 0.10000
ALPHAM . . . . . . . . . . . . . . . . . . . 0.0000
RAYLEIGH DAMPING MULTIPLIERS
ALPHA (MASS) . . . . . . . . . . . . . . . . 0.0000
BETA (STIFFNESS) . . . . . . . . . . . . . . 0.25465E-02
TERMINATE ANALYSIS IF NOT CONVERGED . . . . . .YES (EXIT)
CONVERGENCE CONTROLS. . . . . . . . . . . . . .USE DEFAULTS
PRINT OUTPUT CONTROLS . . . . . . . . . . . . .NO PRINTOUT
DATABASE OUTPUT CONTROLS
ITEM FREQUENCY COMPONENT
ALL NONE
NSOL ALL
RSOL ALL
STRS ALL
EPEL ALL
EPPL ALL
V ALL
A ALL


SOLUTION MONITORING INFO IS WRITTEN TO FILE= ANSYS.mntr

FORCE CONVERGENCE VALUE = 0.2212E-03 CRITERION= 0.1692E-03
DISP CONVERGENCE VALUE = 0.1312E-03 CRITERION= 0.6808E-05
EQUIL ITER 1 COMPLETED. NEW TRIANG MATRIX. MAX DOF INC= -0.4617E-06
FORCE CONVERGENCE VALUE = 0.4175E-05 CRITERION= 0.1738E-03 <<< CONVERGED
DISP CONVERGENCE VALUE = 0.1425E-05 CRITERION= 0.6808E-05 <<< CONVERGED
EQUIL ITER 2 COMPLETED. NEW TRIANG MATRIX. MAX DOF INC = 0.5353E-08
>>> SOLUTION CONVERGED AFTER EQUILIBRIUM ITERATION 2
*** LOAD STEP 428 SUBSTEP 1 COMPLETED. CUM ITER = 3639
*** TIME = 2.14000 TIME INC = 0.500000E-02
*** DAMPING FACTOR FOR NONLINEAR STABILIZATION = 0.3986E+14
*** RESPONSE FREQ = 1471. PERIOD= 0.6799E-03 PTS/CYC = 0.14

FOURTH SYNCHRONIZATION POINT OF MASTER CODE:
LOAD TRANSFER AT THE END OF SOLUTION

FIFTH SYNCHRONIZATION POINT OF MASTER CODE:
GET SLAVES LOCAL CONVERGENCE

FIELD SOLUTION CONVERGENCE

CONVERGENCE OF FIELD SOLVER: ANSYS. . . . . TRUE
CONVERGENCE OF FIELD SOLVER: CFX. . . . . FALSE

SURFACE LOAD TRANSFER CONVERGENCE

CONVERGENCE FOR FIELD 2 ACROSS INTERFACE 0
UX DISP CONVERGENCE. . . . . . -0.34381
UY DISP CONVERGENCE. . . . . . -0.34376
UZ DISP CONVERGENCE. . . . . . 0.36484E-02

CONVERGENCE FOR FIELD 1 ACROSS INTERFACE 1
FX FORCE CONVERGENCE. . . . . 0.12029
FY FORCE CONVERGENCE. . . . . 0.12030
FZ FORCE CONVERGENCE. . . . . 0.10523


FIFTH SYNCHRONIZATION POINT OF MASTER CODE:
SERVE SLAVES THE GLOBAL CONVERGENCE
1

***** ANSYS - ENGINEERING ANALYSIS SYSTEM RELEASE 14.0 *****
ANSYS Multiphysics
00471198 VERSION=WINDOWS x64 09:29:38 APR 30, 2013 CP= 166908.438

non linear FSI mesh study 2--Transient (A5)

. . . . . . . . . . . . . . . . . . . . . . .

MULTI FIELD ANALYSIS STEP OPTIONS

TIME AT BEGINNING OF ANALYSIS. . . . . . . 0.0000
TIME AT END OF ANALYSIS. . . . . . . . . . 2.4000
TIME STEP NUMBER. . . . . . . . . . . . . . . 428
STAGGER ITERATION NUMBER. . . . . . . . . . . 5. CUM MF ITER = 1792

FIELD INFORMATION FOR MULTIFIELD ANALYSIS

CURRENT FIELD NAME FOR ANALYSIS. . . . . ANSYS
TIME AT BEGINNING OF CURRENT ANALYSIS. . . 2.1350
TIME AT END OF CURRENT ANALYSIS. . . . . . 2.1400

THIRD SYNCHRONIZATION POINT OF MASTER CODE:
SERVE SLAVES THE TIME STEP CONTROL INFORMATION TO START A SOLVE

FOURTH SYNCHRONIZATION POINT OF MASTER CODE:
LOAD TRANSFER AT THE BEGINNING OF SOLUTION

FORCE SUM FOR FIELD 1 ACROSS INTERFACE 1

RECEIVING FORCE FX SUM = 1.4169
RECEIVING FORCE FY SUM = 1.4169
RECEIVING FORCE FZ SUM = 0.31195E-02

allocate failed idbptr= 9664266320 nPageInCore= 65536 -db -4096 set

*** NOTE *** CP = 166911.000 TIME= 09:30:41
Page file used.

*** ERROR *** CP = 166911.000 TIME= 09:30:42
An unexpected error ( SIG$SEGV ) has occurred... ANSYS internal data
has been corrupted. ANSYS is unable to recover and will terminate.
Previously saved files are unaffected. Please send the data leading
to this operation to your technical support provider, as this will
allow ANSYS, Inc to improve the program.

Current ANSYS Traceback:
MF_put_surf_loads_ans
MF_trans_surf_loads_master
MF_begin_master
MultiFieldDriver
solvcl
ANSYS

*** PAGE FILE USED ***
NUMBER OF R/W OPERATIONS= 2
MAXIMUM RECORD NUMBER = 32770
RECORD SIZE (I*4 WORDS) = 16384
PAGE FILE SIZE (MB) = 2048.125

+--------------------- A N S Y S S T A T I S T I C S ------------------------+

Release: 14.0 Build: UP20111024 Platform: WINDOWS x64
Date Run: 04/30/2013 Time: 09:30
Windows Process ID: 1380

Compiler: Intel(R) FORTRAN Compiler Version 11.1.0 (Build: 20100414)
Microsoft(R) Visual C/C++ Compiler Version 15.0 (Build: 30729)
Intel(R) Math Kernel Library Version 10.3.3 Product Build 20110314

Number of cores: 2 (Shared Memory Parallel)

GPU Acceleration: Not Requested

Job Name: ANSYS
Working Directory: D:\GUIDE WIRE 2 WAY FSI PROBLEM\Non linear FSI study3\Non linear FSI study 3_pending_tasks\dp0_CFX 1_Solution_1

Elapsed time spent pre-processing model (/PREP7) : 0.8 seconds
Elapsed time spent solution - preprocessing : 1714.1 seconds
Elapsed time spent computing solution : 89076.0 seconds
Elapsed time spent solution - postprocessing : 0.0 seconds
Elapsed time spent post-processing model (/POST1) : 0.0 seconds

Equation solver computational rate : 12716.7 Mflops
Equation solver effective I/O rate : 2077.3 Mbytes/sec

Maximum total memory used : 7833.0 Mbytes
Maximum total memory allocated : 8770.0 Mbytes

+------------------ E N D A N S Y S S T A T I S T I C S -------------------+


*---------------------------------------------------------------------------*
| |
| ANSYS RUN COMPLETED |
| |
|---------------------------------------------------------------------------|
| |
| Release 14.0 UP20111024 WINDOWS x64 |
| |
|---------------------------------------------------------------------------|
| |
| Database Requested(-db) 512 MB Scratch Memory Requested 512 MB |
| Maximum Database Used 4097 MB Maximum Scratch Memory Used 3732 MB |
| |
|---------------------------------------------------------------------------|
| |
| CP Time (sec) = 166911.219 Time = 09:30:43 |
| Elapsed Time (sec) = 173369.000 Date = 04/30/2013 |
| |
*---------------------------------------------------------------------------*

Lance April 30, 2013 09:15

Im guessing some sort of internal error:

Code:

*** ERROR ***                          CP =  166911.000  TIME= 09:30:42
 An unexpected error ( SIG$SEGV ) has occurred...  ANSYS internal data 
 has been corrupted.  ANSYS is unable to recover and will terminate.   
 Previously saved files are unaffected.  Please send the data leading   
 to this operation to your technical support provider, as this will     
 allow ANSYS, Inc to improve the program.

Have you tried to restart the simulation?

kish April 30, 2013 10:18

Quote:

Originally Posted by Lance (Post 424176)
Im guessing some sort of internal error:

Code:

*** ERROR ***                          CP =  166911.000  TIME= 09:30:42
 An unexpected error ( SIG$SEGV ) has occurred...  ANSYS internal data 
 has been corrupted.  ANSYS is unable to recover and will terminate.   
 Previously saved files are unaffected.  Please send the data leading   
 to this operation to your technical support provider, as this will     
 allow ANSYS, Inc to improve the program.

Have you tried to restart the simulation?

Please help me how to restart the simulation. will it run from the last step or from the beginning? Since the solution was running for more than two days.

Thank you

Regards

Kish

kish April 30, 2013 20:29

Dear all


Please help me how to restart my analysis from the previous solution. and I need some explanation from the cfx out file and ANSYS out file which I have posted. Please let me know what is the meaning of the following term?
FIELD SOLUTION CONVERGENCE

CONVERGENCE OF FIELD SOLVER: ANSYS. . . . . TRUE
CONVERGENCE OF FIELD SOLVER: CFX. . . . . FALSE


In some iterations I found both are True

Thank you

Regards

Kish

kish May 2, 2013 10:44

dear all

I have restarted the simulation . Exactly for the same time step it quit with error
any suggestion please

Thank you

Regards

Kish

mvoss May 13, 2013 10:57

Quote:

Originally Posted by kish (Post 424304)
FIELD SOLUTION CONVERGENCE

CONVERGENCE OF FIELD SOLVER: ANSYS. . . . . TRUE
CONVERGENCE OF FIELD SOLVER: CFX. . . . . FALSE

This is telling you that even if the CouplingStep converged for the Ansys Part the fluid domain is not. Itīs basically stating that the system needs more equilibrium iterations on that timestep to converge both sides. you could easily check that by looking at the convergence history for the ANSYS Interface Loads (Strucutral). This should zig-zag over the all timesteps and hit the "0" WITHIN one timestep ... not reaching the max. number of CouplingSteps per Timestep.


Matthias


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