CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Running, Solving & CFD

Problem with complex eigenValues

Register Blogs Members List Search Today's Posts Mark Forums Read

Like Tree1Likes
  • 1 Post By Svensen

Reply
 
LinkBack Thread Tools Display Modes
Old   July 13, 2015, 10:11
Default Problem with complex eigenValues
  #1
Member
 
Join Date: Dec 2014
Posts: 50
Rep Power: 4
Harak is on a distinguished road
Hey,

Using the icoFsiElasticNonLinULSolidFoam solver to simulate beam deformation due to some kind of fluid (resin) I get the following problem with complex eigenValues.

Code:
Create time

Create dynamic mesh for time = 0

Selecting dynamicFvMesh dynamicMotionSolverFvMesh
Selecting motion solver: laplace
Selecting motion diffusivity: quadratic

Reading transportProperties

Reading field p

Reading field U

Reading/calculating face flux field phi

Reading incremental displacement field DU

Patch consoleSolid    Traction boundary field: DU
    nonLinear set to updated Lagrangian
Reading incremental displacement field DV

Reading accumulated velocity field V

Reading accumulated stress field sigma

Reading incremental stress field DSigma

Selecting rheology model linearElastic
Creating constitutive model

Reading coupling properties
Create fluid-to-solid and solid-to-fluid interpolators
Check fluid-to-solid and solid-to-fluid interpolators
Fluid-to-solid face interpolation error: 0.010148376
Solid-to-fluid face interpolation error: 0.01019123

Starting time loop

Time = 0.001

Selecting coupling scheme Aitken

Time = 0.001, iteration: 1
Current fsi under-relaxation factor: 0.01
Maximal accumulated displacement of interface points: 0
Courant Number mean: 0 max: 0 velocity magnitude: 0
DILUPBiCG:  Solving for Ux, Initial residual = 1, Final residual = 8.3132673e-07, No Iterations 18
DILUPBiCG:  Solving for Uy, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG:  Solving for Uz, Initial residual = 0, Final residual = 0, No Iterations 0
GAMG:  Solving for p, Initial residual = 1, Final residual = 8.4510406e-07, No Iterations 31
GAMG:  Solving for p, Initial residual = 0.11197892, Final residual = 4.9492681e-07, No Iterations 23
GAMG:  Solving for p, Initial residual = 0.019307684, Final residual = 5.7220616e-07, No Iterations 19
GAMG:  Solving for p, Initial residual = 0.0051776203, Final residual = 8.4609257e-07, No Iterations 13
GAMG:  Solving for p, Initial residual = 0.0018300923, Final residual = 9.1210219e-07, No Iterations 9
GAMG:  Solving for p, Initial residual = 0.00066812399, Final residual = 6.8161564e-07, No Iterations 7
time step continuity errors : sum local = 1.2555142e-08, global = -2.3714846e-10, cumulative = -2.3714846e-10
GAMG:  Solving for p, Initial residual = 0.53146611, Final residual = 5.978844e-07, No Iterations 29
GAMG:  Solving for p, Initial residual = 0.20182154, Final residual = 9.9028612e-07, No Iterations 24
GAMG:  Solving for p, Initial residual = 0.042800682, Final residual = 5.2895856e-07, No Iterations 21
GAMG:  Solving for p, Initial residual = 0.011775962, Final residual = 9.6208771e-07, No Iterations 15
GAMG:  Solving for p, Initial residual = 0.0041584696, Final residual = 4.5080195e-07, No Iterations 13
GAMG:  Solving for p, Initial residual = 0.0015133582, Final residual = 7.2392118e-07, No Iterations 8
time step continuity errors : sum local = 5.5095195e-09, global = 2.1325662e-10, cumulative = -2.3891839e-11
GAMG:  Solving for p, Initial residual = 0.29927741, Final residual = 9.4244826e-07, No Iterations 24
GAMG:  Solving for p, Initial residual = 0.012474404, Final residual = 9.8173954e-07, No Iterations 16
GAMG:  Solving for p, Initial residual = 0.0021021264, Final residual = 9.130113e-07, No Iterations 10
GAMG:  Solving for p, Initial residual = 0.00060303569, Final residual = 7.4261747e-07, No Iterations 7
GAMG:  Solving for p, Initial residual = 0.00022272133, Final residual = 5.699134e-07, No Iterations 6
GAMG:  Solving for p, Initial residual = 8.4422059e-05, Final residual = 4.7794747e-07, No Iterations 5
time step continuity errors : sum local = 2.4638291e-09, global = 9.6306776e-11, cumulative = 7.2414937e-11
GAMG:  Solving for p, Initial residual = 0.15397893, Final residual = 4.9561848e-07, No Iterations 21
GAMG:  Solving for p, Initial residual = 0.0040461499, Final residual = 8.909345e-07, No Iterations 12
GAMG:  Solving for p, Initial residual = 0.00060316435, Final residual = 7.2521584e-07, No Iterations 6
GAMG:  Solving for p, Initial residual = 0.00015816922, Final residual = 8.635744e-07, No Iterations 5
GAMG:  Solving for p, Initial residual = 5.5933466e-05, Final residual = 6.7512527e-07, No Iterations 4
GAMG:  Solving for p, Initial residual = 2.0009206e-05, Final residual = 7.0327084e-07, No Iterations 3
time step continuity errors : sum local = 3.0437577e-09, global = 5.0514774e-11, cumulative = 1.2292971e-10
GAMG:  Solving for p, Initial residual = 0.09966961, Final residual = 7.9882574e-07, No Iterations 19
GAMG:  Solving for p, Initial residual = 0.0021026035, Final residual = 7.7451051e-07, No Iterations 11
GAMG:  Solving for p, Initial residual = 0.0003114969, Final residual = 8.0088546e-07, No Iterations 6
GAMG:  Solving for p, Initial residual = 7.9168706e-05, Final residual = 4.1457659e-07, No Iterations 5
GAMG:  Solving for p, Initial residual = 2.7196661e-05, Final residual = 4.5421346e-07, No Iterations 4
GAMG:  Solving for p, Initial residual = 9.7404879e-06, Final residual = 9.6395309e-07, No Iterations 2
time step continuity errors : sum local = 3.742613e-09, global = 3.7893867e-11, cumulative = 1.6082358e-10
GAMG:  Solving for p, Initial residual = 0.067709768, Final residual = 3.3787923e-07, No Iterations 19
GAMG:  Solving for p, Initial residual = 0.001238497, Final residual = 6.5694878e-07, No Iterations 9
GAMG:  Solving for p, Initial residual = 0.00018346641, Final residual = 9.203233e-07, No Iterations 5
GAMG:  Solving for p, Initial residual = 4.7386527e-05, Final residual = 5.6317931e-07, No Iterations 4
GAMG:  Solving for p, Initial residual = 1.6343804e-05, Final residual = 6.4763955e-07, No Iterations 3
GAMG:  Solving for p, Initial residual = 6.0068916e-06, Final residual = 6.3302699e-07, No Iterations 2
time step continuity errors : sum local = 2.2796623e-09, global = 4.0342121e-11, cumulative = 2.011657e-10
GAMG:  Solving for p, Initial residual = 0.049479011, Final residual = 4.0133808e-07, No Iterations 19
GAMG:  Solving for p, Initial residual = 0.0008968961, Final residual = 9.4596208e-07, No Iterations 8
GAMG:  Solving for p, Initial residual = 0.00014130527, Final residual = 8.4796864e-07, No Iterations 5
GAMG:  Solving for p, Initial residual = 3.7615407e-05, Final residual = 4.6315112e-07, No Iterations 4
GAMG:  Solving for p, Initial residual = 1.3117843e-05, Final residual = 5.2243324e-07, No Iterations 3
GAMG:  Solving for p, Initial residual = 4.9612375e-06, Final residual = 5.3065942e-07, No Iterations 2
time step continuity errors : sum local = 1.8024859e-09, global = 3.4321021e-11, cumulative = 2.3548672e-10
GAMG:  Solving for p, Initial residual = 0.037470098, Final residual = 9.1049378e-07, No Iterations 17
GAMG:  Solving for p, Initial residual = 0.00062369277, Final residual = 7.6589462e-07, No Iterations 7
GAMG:  Solving for p, Initial residual = 9.851143e-05, Final residual = 5.9136462e-07, No Iterations 5
GAMG:  Solving for p, Initial residual = 2.55739e-05, Final residual = 7.3420652e-07, No Iterations 3
GAMG:  Solving for p, Initial residual = 9.0831531e-06, Final residual = 8.9706984e-07, No Iterations 2
GAMG:  Solving for p, Initial residual = 3.539342e-06, Final residual = 4.1343948e-07, No Iterations 2
time step continuity errors : sum local = 1.3410325e-09, global = 4.1947225e-11, cumulative = 2.7743395e-10
GAMG:  Solving for p, Initial residual = 0.029567073, Final residual = 8.7894614e-07, No Iterations 17
GAMG:  Solving for p, Initial residual = 0.00049695739, Final residual = 7.2217496e-07, No Iterations 7
GAMG:  Solving for p, Initial residual = 8.0604414e-05, Final residual = 5.182067e-07, No Iterations 5
GAMG:  Solving for p, Initial residual = 2.2075999e-05, Final residual = 7.3302099e-07, No Iterations 3
GAMG:  Solving for p, Initial residual = 7.8158024e-06, Final residual = 8.0647039e-07, No Iterations 2
GAMG:  Solving for p, Initial residual = 3.162127e-06, Final residual = 9.8778579e-07, No Iterations 1
time step continuity errors : sum local = 3.0850137e-09, global = 3.9143509e-11, cumulative = 3.1657745e-10
GAMG:  Solving for p, Initial residual = 0.02352783, Final residual = 7.2779874e-07, No Iterations 17
GAMG:  Solving for p, Initial residual = 0.00037960579, Final residual = 7.6354505e-07, No Iterations 6
GAMG:  Solving for p, Initial residual = 6.1634295e-05, Final residual = 4.0162528e-07, No Iterations 5
GAMG:  Solving for p, Initial residual = 1.630773e-05, Final residual = 4.8443595e-07, No Iterations 3
GAMG:  Solving for p, Initial residual = 5.7762329e-06, Final residual = 5.7300479e-07, No Iterations 2
GAMG:  Solving for p, Initial residual = 2.2465927e-06, Final residual = 6.8744055e-07, No Iterations 1
time step continuity errors : sum local = 2.0815317e-09, global = 3.8350853e-11, cumulative = 3.5492831e-10
Setting traction on solid patch
Total traction force = (9.5242657e-11 -3.677489e-12 7.535462e-10)
--> FOAM Warning : 
    From function eigenValues(const tensor&)
    in file primitives/Tensor/tensor/tensor.C at line 170
    complex eigenvalues detected for tensor: (-9177.5336 -1.619439e-05 0.012441039 94407.607 -82602.655 7.4239701e+08 -74434408 62320794 -5.8801867e+11)
.
.
.
.
.
--> FOAM Warning : 
    From function eigenValues(const tensor&)
    in file primitives/Tensor/tensor/tensor.C at line 170
    complex eigenvalues detected for tensor: (-5.5240793e+21 0 0 -5.9533364e+32 4.9617278e+32 -4.6815738e+36 -3.2393035e+35 2.6998181e+35 -2.5473779e+39)
Floating point exception (core dumped)
I'm using the default values of the HronTurekFsi tutorial for the icoFsiElasticNonLinULSolidFoam solver. So, I didn't change any setting for nor the fluid neither the solid domain.

I already read the tensor.C file trying to understand it but I'm not that good in C++ :/ Maybe the solution for my problem is given there and I'm just incapable to get it '

Could you guys please help me? I'm stuck with this for days now Every suggestion is very welcomed
Harak is offline   Reply With Quote

Old   July 14, 2015, 02:31
Default
  #2
Senior Member
 
Join Date: Jan 2015
Posts: 122
Rep Power: 3
Svensen is on a distinguished road
I think that no one find a solution for this problem... I'm also searching for solution but without success. foam-extend is not well-supported by community.
Svensen is offline   Reply With Quote

Old   July 20, 2015, 08:36
Default
  #3
Member
 
Join Date: Dec 2014
Posts: 50
Rep Power: 4
Harak is on a distinguished road
Quote:
Originally Posted by Svensen View Post
I think that no one find a solution for this problem... I'm also searching for solution but without success. foam-extend is not well-supported by community.
Do you have this problem, too?
Harak is offline   Reply With Quote

Old   July 21, 2015, 01:19
Default
  #4
Senior Member
 
Join Date: Jan 2015
Posts: 122
Rep Power: 3
Svensen is on a distinguished road
Yes, I have this problem too and I don't find a solution for it...
rasool_soofi likes this.
Svensen is offline   Reply With Quote

Old   August 3, 2015, 10:38
Default
  #5
New Member
 
rasool soofi nooghabi
Join Date: Mar 2015
Posts: 15
Rep Power: 3
rasool_soofi is on a distinguished road
hi
can you find a solution for this problem ?
I have this problem, too
thank you
rasool_soofi is offline   Reply With Quote

Old   August 4, 2015, 08:38
Default
  #6
Member
 
Join Date: Dec 2014
Posts: 50
Rep Power: 4
Harak is on a distinguished road
Quote:
Originally Posted by rasool_soofi View Post
hi
can you find a solution for this problem ?
I have this problem, too
thank you
Hey,

Yes, actually I found my problem. It was due to a false numbering of the blocks with hex ().
The User's Guide says:
Quote:
Each block has a local coordinate system that must be right-handed. A right-handed set of axes is defined such that to an observer looking down the axis, with nearest them, the arc from a point on the axis to a point on the axis is in a clockwise sense.
I accidentally read over this part

Hope, it helps for you..
Harak is offline   Reply With Quote

Old   November 2, 2015, 11:18
Default
  #7
Member
 
Join Date: Dec 2014
Posts: 50
Rep Power: 4
Harak is on a distinguished road
Svensen:
Quote:
Yes, I have this problem too and I don't find a solution for it...
and rasool_sosfi:
Quote:
hi
can you find a solution for this problem ?
I have this problem, too
thank you
Do you guys still have this problem?
Harak is offline   Reply With Quote

Old   November 16, 2015, 02:36
Default
  #8
New Member
 
rasool soofi nooghabi
Join Date: Mar 2015
Posts: 15
Rep Power: 3
rasool_soofi is on a distinguished road
hi
yes ,i have this problem yet
i am using icofsinonlinulsolidfoam sover from foam-extend 3.1
when i run my case with geometry scale of 200 and time step of 0.01 i dont have this problem
but when i run my case with geometry scale of 1 and time step of 0.000001 this problem occur and stop my solution .
courant number during solution is low.

myfsi.log file
Attached Images
File Type: jpg fsi.jpg (114.2 KB, 12 views)
rasool_soofi is offline   Reply With Quote

Old   November 17, 2015, 03:18
Default
  #9
New Member
 
rasool soofi nooghabi
Join Date: Mar 2015
Posts: 15
Rep Power: 3
rasool_soofi is on a distinguished road
thank you harak !

my case geometery generated by gambit .

what means (right handed coordinate ...) in gambit mesh ??
rasool_soofi is offline   Reply With Quote

Old   November 21, 2015, 04:22
Default
  #10
Member
 
Join Date: Dec 2014
Posts: 50
Rep Power: 4
Harak is on a distinguished road
Hi Rasool,

sorry for the late answer.
However, I assume that this problem occurs at your case because you're using a third party mesh generation tool. The solver icofsinonlinulsolidfoam needs a 1:1 face match between the fluid and the solid patch. I'm pretty sure that your mesh isn't considering this fact.

Try using blockMesh for your geometry I hope your geometry isn't that complicated

And please let me know if this is working for you.
Harak is offline   Reply With Quote

Old   November 24, 2015, 06:01
Default
  #11
Senior Member
 
Join Date: Jan 2015
Posts: 122
Rep Power: 3
Svensen is on a distinguished road
Does anyone find a solution ?
Svensen is offline   Reply With Quote

Old   January 26, 2016, 02:48
Default
  #12
Senior Member
 
Join Date: Jan 2015
Posts: 122
Rep Power: 3
Svensen is on a distinguished road
Does anyone found a solution ?
Svensen is offline   Reply With Quote

Reply

Tags
complex eigenvalues, fluid structure, fsi

Thread Tools
Display Modes

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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
conduction problem venkataramana OpenFOAM 3 December 1, 2013 08:30
UDF compiling problem Wouter Fluent UDF and Scheme Programming 6 June 6, 2012 04:43
Problem Importing Geometry ProE to CFX fatb0y CFX 3 January 14, 2012 20:42
Problem in k-eps turbulence code in complex geometry sontukaku Main CFD Forum 2 December 28, 2010 01:44
Adiabatic and Rotating wall (Convection problem) ParodDav CFX 5 April 29, 2007 19:13


All times are GMT -4. The time now is 08:17.