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Hello, I have used OOFEM to calculate the static analysis of a structure with fixed support. Static analysis only considers the action of gravity. I used the Sparse solvers "DSS" with the following settings in my input file.
----------------------------------------------------------------
StaticStructural lstype 4 smtype 8 nsteps 1 nmodules 1
vtkxml tstep_all domain_all primvars 1 1 vars 2 4 1 stype 1
------------------------------------------------------------------
When the Node number less than 1242748, I can get the right result. But when the node number more than 1242748, the program automatically end with the following information.
-----------------------------------------------------------------------------------------------------
E:\CAE\oofem-2.5\oofem-2.5-build-P\Release>oofem -f d:\CAE_Soft\VV\VV_LS_Q_20190929_0.07.in
____________________________________________________
OOFEM - Finite Element Solver
Copyright (C) 1994-2017 Borek Patzak
____________________________________________________
___FemCAD--DirectSparse_Solver______
Richard Vondracek (c) 2001-2003
Sparse Direct initialized
Loading sparse matrix
number of equations : 3826593
number of nonzeros : 268429185 nonzeros
ordering : ApproxMinimumDegree
Symbolic QG factorization :
33.391 s
Allocating block sparse matrix
sparse matrix size : -15909257 kB..
E:\CAE\oofem-2.5\oofem-2.5-build-P\Release>
-----------------------------------------------------------------------------------------------------------
I want to know if the oofem has restrictions on element number or not? What is the reason on this problem, and how to avoid this problem, because I want to use the oofem to analysis structures with large size.
Thank you very much for all your help!
Hello, I have used OOFEM to test the "NlDEIDynamic" analysis. The structure has fixed support on its one side, and has the specified displacement on its other side. I used Salome to import the STP file of the solved assembly, then generated the grid, output the UNV file, and use unv2oofem to get the input file of oofem. But when I run the oofem, I obtain the following error, and is there something wrong with my OOFEM input file settings? I need help.
_______________________________________________________
Error: (E:\CAE\oofem-2.5\oofem-2.5\oofem-2.5\src\oofemlib\fei3dtetlin.C:79)
In oofem::FEI3dTetLin::evaldNdx:
negative volume
_______________________________________________________
No backtrace available
Total 1 error(s) and 0 warning(s) reported
oofem exit code 1
_______________________________________________________
The ctrl file is shown as following. The input file is as shown in appendix.
--------------------------------------------------------------------------
BWG_linearstatic_sets_20190929_1.out
This example shows NlDEIDynamic analysis. It will use sets.
NlDEIDynamic nsteps 2000 dumpcoef 0 deltaT 0.001 nmodules 1
vtkxml tstep_all domain_all primvars 1 1 vars 2 4 1 stype 1
domain 3d
OutputManager tstep_all dofman_all element_all
ncrosssect 1 nmat 1 nbc 2 nic 0 nltf 2 nset 3
SimpleCS 1 material 1 set 1
IsoLE 1 d 7600.0 E 196.e9 n 0.3 tAlpha 0.0
BoundaryCondition 1 loadTimeFunction 1 dofs 3 1 2 3 values 3 0.0 0.0 0.0 set 2
BoundaryCondition 2 loadTimeFunction 2 dofs 3 1 2 3 values 3 1.0 0.0 0.0 set 3
ConstantFunction 1 f(t) 1.0
PiecewiseLinFunction 2 npoints 2 t 2 0 5 f(t) 2 0 0.001
set 1 elements
set 2 nodes
set 3 nodes
group Group_All_Vol
elemprop set 1
etype[111] LTRSpace
group Group_Fix_Face
nodeprop bc 3 1 1 1 set 2
group Group_Load_Face
nodeprop set 3
-------------------------------------------------------------------------------------------------
Dear Nitramkaroh,
Thank you very much for all your help. I am sorry for my mistake about applying the body load twice. It is the reason, and now the results are pefect when using the same mesh, element type, integration rule. Your advice is really important for our OOFEM beginners.
Thank you again.
Thank you very much for all your help. I have upload my input file.
Hello, I have used OOFEM and commercial software Ansys to calculate the static analysis of the same structure with fixed support. Static analysis only considers the action of gravity. But the output of OOFEM is quite different from that of Ansys. Is there something wrong with my OOFEM input file settings? I need help. I used Salome to import the STP file of the solved assembly, then generated the grid, output the UNV file, and use unv2oofem to get the input file of oofem. The ctrl file of static analysis and modal analysis are shown as following.
------------------------------static analysis--------------------------------------------
VV_linearstatic_sets_20190929_1.out
This example shows linearstatic analysis. It will use sets.
linearstatic lstype 4 smtype 8 nsteps 1 nmodules 1
vtkxml tstep_all domain_all primvars 1 1 vars 2 4 1 stype 1
domain 3d
OutputManager tstep_all dofman_all element_all
ncrosssect 1 nmat 1 nbc 2 nic 0 nltf 1 nset 2
SimpleCS 1 material 1 set 1
IsoLE 1 d 7600.0 E 196.e9 n 0.3 tAlpha 0.0
BoundaryCondition 1 loadTimeFunction 1 dofs 3 1 2 3 values 3 0.0 0.0 0.0 set 2
DeadWeight 2 loadTimeFunction 1 Components 3 0. 0. -9.8066 set 1
ConstantFunction 1 f(t) 1.0
set 1 elements
set 2 nodes
group Group_All
elemprop mat 1 crosssect 1 bodyLoads 1 2 set 1
etype[118] QTRSpace
group Group_LR
nodeprop bc 3 1 1 1 set 2
-------------------------------------------------------------------------------------------------
The input file is as shown in appendix. I have tested two Sparse solvers "DSS" and "IML" . The maximum displacement magnitude obtained by "DSS" is 5.2E-5, and which obtained by "IML" is only 2.9E-6, but the maximum displacement magnitude obtained by Ansys is 3.29E-5. I don't konw why, and which solver of oofem is more appropriate?
Dear all,
I have built OOFEM on win7 by using Microsoft Visual Studio 2017 and Intel® Parallel Studio XE 2018. I set "USE_PARDISO_ORG"= On. I downloaded the "libpardiso600-WIN-X86-64.lib" from https://www.pardiso-project.org/. But when I built the project in VS2017, it showed the “LINK : fatal error LNK1181: could not find the “gfortran.lib” ” . How can I obtain the “gfortran.lib” in Win7?
Thank you very much for all your help.
A similar problem arises in another simple example.
VV_Eigen_exam_sets.out
eigen vibration analysis. It will use sets.
EigenValueDynamic nroot 10 rtolv 1.e-2 nmodules 1 stype 1
errorcheck
domain 3d
OutputManager tstep_all dofman_all element_all
ndofman 64 nelem 127 ncrosssect 1 nmat 1 nbc 0 nic 0 nltf 1 nset 1 nxfemman 0
node 1 coords 3 72.3713 -31.1808 20
node 2 coords 3 72.3713 -31.1808 0
node 3 coords 3 -72.3713 -31.1808 20
node 4 coords 3 -72.3713 -31.1808 0
node 5 coords 3 -72.3713 31.1808 20
node 6 coords 3 -72.3713 31.1808 0
node 7 coords 3 72.3713 31.1808 20
node 8 coords 3 72.3713 31.1808 0
node 9 coords 3 -51.6938 31.1808 20
node 10 coords 3 -31.0163 31.1808 20
node 11 coords 3 -10.3388 31.1808 20
node 12 coords 3 10.3388 31.1808 20
node 13 coords 3 31.0163 31.1808 20
node 14 coords 3 51.6938 31.1808 20
node 15 coords 3 -72.3713 -10.3936 20
node 16 coords 3 -72.3713 10.3936 20
node 17 coords 3 51.6938 -31.1808 20
node 18 coords 3 31.0163 -31.1808 20
node 19 coords 3 10.3388 -31.1808 20
node 20 coords 3 -10.3388 -31.1808 20
node 21 coords 3 -31.0163 -31.1808 20
node 22 coords 3 -51.6938 -31.1808 20
node 23 coords 3 72.3713 10.3936 20
node 24 coords 3 72.3713 -10.3936 20
node 25 coords 3 72.3713 10.3936 0
node 26 coords 3 72.3713 -10.3936 0
node 27 coords 3 51.6938 -31.1808 0
node 28 coords 3 31.0163 -31.1808 0
node 29 coords 3 10.3388 -31.1808 0
node 30 coords 3 -10.3388 -31.1808 0
node 31 coords 3 -31.0163 -31.1808 0
node 32 coords 3 -51.6938 -31.1808 0
node 33 coords 3 -72.3713 -10.3936 0
node 34 coords 3 -72.3713 10.3936 0
node 35 coords 3 -51.6938 31.1808 0
node 36 coords 3 -31.0163 31.1808 0
node 37 coords 3 -10.3388 31.1808 0
node 38 coords 3 10.3388 31.1808 0
node 39 coords 3 31.0163 31.1808 0
node 40 coords 3 51.6938 31.1808 0
node 41 coords 3 -38.4015 11.3835 20
node 42 coords 3 -18.1291 12.3569 20
node 43 coords 3 0.132512 15.975 20
node 44 coords 3 18.4998 12.3435 20
node 45 coords 3 38.7179 11.2388 20
node 46 coords 3 57.4213 9.91026 20
node 47 coords 3 46.6557 -10.8253 20
node 48 coords 3 23.6561 -11.2505 20
node 49 coords 3 0.178633 -8.66691 20
node 50 coords 3 -23.311 -11.164 20
node 51 coords 3 -46.9144 -10.3804 20
node 52 coords 3 -57.3718 10.0283 20
node 53 coords 3 56.2006 3.6769 0
node 54 coords 3 53.3824 -15.5522 0
node 55 coords 3 16.4235 -10.8041 0
node 56 coords 3 -22.8921 -15.3127 0
node 57 coords 3 -52.321 11.4885 0
node 58 coords 3 -23.564 9.20307 0
node 59 coords 3 21.0225 13.0682 0
node 60 coords 3 36.273 -6.36866 0
node 61 coords 3 -3.94464 -11.9524 0
node 62 coords 3 -43.8958 -10.9229 0
node 63 coords 3 0.512346 11.6697 0
node 64 coords 3 39.5607 15.36 0
LTRSpace 169 nodes 4 58 41 36 57 mat 1 crosssect 1
LTRSpace 170 nodes 4 36 41 9 35 mat 1 crosssect 1
LTRSpace 171 nodes 4 20 50 56 21 mat 1 crosssect 1
LTRSpace 172 nodes 4 22 4 33 32 mat 1 crosssect 1
LTRSpace 173 nodes 4 38 39 13 59 mat 1 crosssect 1
LTRSpace 174 nodes 4 31 30 56 21 mat 1 crosssect 1
LTRSpace 175 nodes 4 61 19 20 30 mat 1 crosssect 1
LTRSpace 176 nodes 4 40 53 23 46 mat 1 crosssect 1
LTRSpace 177 nodes 4 58 61 42 50 mat 1 crosssect 1
LTRSpace 178 nodes 4 40 46 23 7 mat 1 crosssect 1
LTRSpace 179 nodes 4 40 64 53 46 mat 1 crosssect 1
LTRSpace 180 nodes 4 24 17 47 54 mat 1 crosssect 1
LTRSpace 181 nodes 4 49 63 42 43 mat 1 crosssect 1
LTRSpace 182 nodes 4 19 61 55 29 mat 1 crosssect 1
LTRSpace 183 nodes 4 42 63 49 61 mat 1 crosssect 1
LTRSpace 184 nodes 4 20 61 56 50 mat 1 crosssect 1
LTRSpace 185 nodes 4 13 39 40 64 mat 1 crosssect 1
LTRSpace 186 nodes 4 23 53 25 26 mat 1 crosssect 1
LTRSpace 187 nodes 4 24 26 2 54 mat 1 crosssect 1
LTRSpace 188 nodes 4 29 19 61 30 mat 1 crosssect 1
LTRSpace 189 nodes 4 51 41 62 57 mat 1 crosssect 1
LTRSpace 190 nodes 4 5 6 9 52 mat 1 crosssect 1
LTRSpace 191 nodes 4 55 61 49 63 mat 1 crosssect 1
LTRSpace 192 nodes 4 42 41 36 58 mat 1 crosssect 1
LTRSpace 193 nodes 4 56 50 58 62 mat 1 crosssect 1
LTRSpace 194 nodes 4 32 21 51 22 mat 1 crosssect 1
LTRSpace 195 nodes 4 13 39 64 59 mat 1 crosssect 1
LTRSpace 196 nodes 4 44 45 60 59 mat 1 crosssect 1
LTRSpace 197 nodes 4 40 7 23 25 mat 1 crosssect 1
LTRSpace 198 nodes 4 55 49 43 63 mat 1 crosssect 1
LTRSpace 199 nodes 4 60 64 45 53 mat 1 crosssect 1
LTRSpace 200 nodes 4 24 1 17 54 mat 1 crosssect 1
LTRSpace 201 nodes 4 47 54 60 53 mat 1 crosssect 1
LTRSpace 202 nodes 4 36 41 35 57 mat 1 crosssect 1
LTRSpace 203 nodes 4 18 28 55 60 mat 1 crosssect 1
LTRSpace 204 nodes 4 40 25 23 53 mat 1 crosssect 1
LTRSpace 205 nodes 4 41 42 36 10 mat 1 crosssect 1
LTRSpace 206 nodes 4 9 6 35 52 mat 1 crosssect 1
LTRSpace 207 nodes 4 45 46 47 53 mat 1 crosssect 1
LTRSpace 208 nodes 4 42 61 49 50 mat 1 crosssect 1
LTRSpace 209 nodes 4 24 54 53 26 mat 1 crosssect 1
LTRSpace 210 nodes 4 62 31 56 21 mat 1 crosssect 1
LTRSpace 211 nodes 4 27 1 2 54 mat 1 crosssect 1
LTRSpace 212 nodes 4 57 52 51 41 mat 1 crosssect 1
LTRSpace 213 nodes 4 18 60 55 48 mat 1 crosssect 1
LTRSpace 214 nodes 4 18 48 55 19 mat 1 crosssect 1
LTRSpace 215 nodes 4 17 1 27 54 mat 1 crosssect 1
LTRSpace 216 nodes 4 47 48 60 18 mat 1 crosssect 1
LTRSpace 217 nodes 4 29 55 18 28 mat 1 crosssect 1
LTRSpace 218 nodes 4 45 64 14 46 mat 1 crosssect 1
LTRSpace 219 nodes 4 32 62 51 21 mat 1 crosssect 1
LTRSpace 220 nodes 4 14 64 40 46 mat 1 crosssect 1
LTRSpace 221 nodes 4 24 54 2 1 mat 1 crosssect 1
LTRSpace 222 nodes 4 29 19 18 55 mat 1 crosssect 1
LTRSpace 223 nodes 4 41 52 35 57 mat 1 crosssect 1
LTRSpace 224 nodes 4 54 28 18 60 mat 1 crosssect 1
LTRSpace 225 nodes 4 52 41 35 9 mat 1 crosssect 1
LTRSpace 226 nodes 4 58 63 42 61 mat 1 crosssect 1
LTRSpace 227 nodes 4 62 41 58 57 mat 1 crosssect 1
LTRSpace 228 nodes 4 47 24 53 46 mat 1 crosssect 1
LTRSpace 229 nodes 4 62 50 51 21 mat 1 crosssect 1
LTRSpace 230 nodes 4 62 32 31 21 mat 1 crosssect 1
LTRSpace 231 nodes 4 19 48 55 49 mat 1 crosssect 1
LTRSpace 232 nodes 4 19 49 55 61 mat 1 crosssect 1
LTRSpace 233 nodes 4 53 24 23 46 mat 1 crosssect 1
LTRSpace 234 nodes 4 36 10 9 41 mat 1 crosssect 1
LTRSpace 235 nodes 4 55 63 43 59 mat 1 crosssect 1
LTRSpace 236 nodes 4 7 25 40 8 mat 1 crosssect 1
LTRSpace 237 nodes 4 32 33 51 62 mat 1 crosssect 1
LTRSpace 238 nodes 4 20 30 56 61 mat 1 crosssect 1
LTRSpace 239 nodes 4 28 54 17 27 mat 1 crosssect 1
LTRSpace 240 nodes 4 44 59 60 55 mat 1 crosssect 1
LTRSpace 241 nodes 4 55 59 43 44 mat 1 crosssect 1
LTRSpace 242 nodes 4 47 60 45 53 mat 1 crosssect 1
LTRSpace 243 nodes 4 51 50 62 41 mat 1 crosssect 1
LTRSpace 244 nodes 4 44 55 60 48 mat 1 crosssect 1
LTRSpace 245 nodes 4 62 50 58 41 mat 1 crosssect 1
LTRSpace 246 nodes 4 37 38 43 63 mat 1 crosssect 1
LTRSpace 247 nodes 4 56 30 20 21 mat 1 crosssect 1
LTRSpace 248 nodes 4 56 50 62 21 mat 1 crosssect 1
LTRSpace 249 nodes 4 47 48 45 60 mat 1 crosssect 1
LTRSpace 250 nodes 4 53 64 45 46 mat 1 crosssect 1
LTRSpace 251 nodes 4 62 33 51 57 mat 1 crosssect 1
LTRSpace 252 nodes 4 7 14 40 46 mat 1 crosssect 1
LTRSpace 253 nodes 4 32 22 51 33 mat 1 crosssect 1
LTRSpace 254 nodes 4 33 52 51 57 mat 1 crosssect 1
LTRSpace 255 nodes 4 42 41 58 50 mat 1 crosssect 1
LTRSpace 256 nodes 4 13 64 40 14 mat 1 crosssect 1
LTRSpace 257 nodes 4 54 60 18 47 mat 1 crosssect 1
LTRSpace 258 nodes 4 44 48 49 55 mat 1 crosssect 1
LTRSpace 259 nodes 4 23 24 53 26 mat 1 crosssect 1
LTRSpace 260 nodes 4 63 37 58 42 mat 1 crosssect 1
LTRSpace 261 nodes 4 44 13 45 59 mat 1 crosssect 1
LTRSpace 262 nodes 4 35 6 57 52 mat 1 crosssect 1
LTRSpace 263 nodes 4 55 44 43 49 mat 1 crosssect 1
LTRSpace 264 nodes 4 59 63 43 38 mat 1 crosssect 1
LTRSpace 265 nodes 4 56 61 58 50 mat 1 crosssect 1
LTRSpace 266 nodes 4 47 54 53 24 mat 1 crosssect 1
LTRSpace 267 nodes 4 54 47 18 17 mat 1 crosssect 1
LTRSpace 268 nodes 4 37 36 58 42 mat 1 crosssect 1
LTRSpace 269 nodes 4 14 64 45 13 mat 1 crosssect 1
LTRSpace 270 nodes 4 49 19 20 61 mat 1 crosssect 1
LTRSpace 271 nodes 4 54 17 18 28 mat 1 crosssect 1
LTRSpace 272 nodes 4 45 13 64 59 mat 1 crosssect 1
LTRSpace 273 nodes 4 49 61 20 50 mat 1 crosssect 1
LTRSpace 274 nodes 4 44 48 60 45 mat 1 crosssect 1
LTRSpace 275 nodes 4 45 64 60 59 mat 1 crosssect 1
LTRSpace 276 nodes 4 44 59 43 12 mat 1 crosssect 1
LTRSpace 277 nodes 4 22 3 15 4 mat 1 crosssect 1
LTRSpace 278 nodes 4 15 4 33 22 mat 1 crosssect 1
LTRSpace 279 nodes 4 37 63 43 42 mat 1 crosssect 1
LTRSpace 280 nodes 4 59 38 43 12 mat 1 crosssect 1
LTRSpace 281 nodes 4 6 52 5 34 mat 1 crosssect 1
LTRSpace 282 nodes 4 16 5 52 34 mat 1 crosssect 1
LTRSpace 283 nodes 4 6 34 57 52 mat 1 crosssect 1
LTRSpace 284 nodes 4 10 42 36 37 mat 1 crosssect 1
LTRSpace 285 nodes 4 42 10 11 37 mat 1 crosssect 1
LTRSpace 286 nodes 4 37 42 43 11 mat 1 crosssect 1
LTRSpace 287 nodes 4 43 11 12 38 mat 1 crosssect 1
LTRSpace 288 nodes 4 37 11 43 38 mat 1 crosssect 1
LTRSpace 289 nodes 4 13 12 38 59 mat 1 crosssect 1
LTRSpace 290 nodes 4 44 12 13 59 mat 1 crosssect 1
LTRSpace 291 nodes 4 51 15 52 33 mat 1 crosssect 1
LTRSpace 292 nodes 4 16 15 33 52 mat 1 crosssect 1
LTRSpace 293 nodes 4 22 15 51 33 mat 1 crosssect 1
LTRSpace 294 nodes 4 34 16 33 52 mat 1 crosssect 1
LTRSpace 295 nodes 4 34 33 57 52 mat 1 crosssect 1
SimpleCS 1 mat 1 set 1
IsoLE 1 d 7600.0 E 196.e9 n 0.3 tAlpha 0.0
ConstantFunction 1 f(t) 1.0
set 1 elements 127 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295
Hello All,
I have done a eigen analysis by using LTRSpace element. The output is “Matrices are not positive definite” with "EigenValueDynamic nroot 10 rtolv 1.e-6 nmodules 1 stype 0"。 But I don't know what the problem is. When I changed the stype as "EigenValueDynamic nroot 10 rtolv 1.e-6 nmodules 1 stype 1", the output is as following.
Eigen Values (Omega^2) are:
-----------------
5.97975441e-06 6.71889742e-06 7.66905405e-06 7.86784208e-06 7.97187807e-06
8.25501246e-06 8.73372381e-06 8.77186094e-06 1.42822084e-05 1.46772119e-05
I use the international system of units. The grid is partitioned by Salome 9.3.0, and then the input file is generated by Unv2oofem convertor.
Thank you very much for your help.
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