Page 1 of 1
WhitneyAV / Solution trivially zero!
Posted: 15 Mar 2024, 23:17
by c0d3runn3r
Hi guys, I've spent a long time working on this without success. At last in desperation I turn to you for help!
- mesh.png
- (369.17 KiB) Not downloaded yet
I have a typical coil-core-air 3-body system as you can see. I'm using CoilSolver and WhitneyAV. Things converge and ParaView shows a coilcurrent with the correct magnitude, but almost no magnetic field (~1e-18).
I am getting the following in the solver log but can't figure out what I am doing wrong:
Code: Select all
MagnetoDynamicsCalcFields: Solving for field: current density[current density:3]
SolveLinearSystem: Solution trivially zero!
SolveLinearSystem: Solution trivially zero!
SolveLinearSystem: Solution trivially zero!
I've read various forum posts and tried changing various parameters including "Linear System Normwise Backward Error = Logical True" etc from
this post without success. What am I missing?
sif, geo and msh files below in the first comment
Re: WhitneyAV / Solution trivially zero!
Posted: 15 Mar 2024, 23:18
by c0d3runn3r
Here are the relevant files - looks like there is a 3 attchments/post limitation
Re: WhitneyAV / Solution trivially zero!
Posted: 16 Mar 2024, 11:56
by kevinarden
You have a mesh with non-conforming bodies, Elmer communicates data between the body through shared nodes or mortar boundary conditions.
- mesh.png (159.58 KiB) Viewed 397 times
See Section 9.3 of this manual
https://www.nic.funet.fi/pub/sci/physic ... dElmer.pdf
Re: WhitneyAV / Solution trivially zero!
Posted: 18 Mar 2024, 18:49
by c0d3runn3r
Hi kevinarden, thanks for your reply. Yes thank you, I also realized my mesh was non conformal. My new mesh is attached.
- Immediately after generating a conforming mesh I started getting segmentation fault and core dump (below).
- I then tried to slim my file down to just the CoilSolver (so I could examine a simplified case)
and the simulation runs with 1 iteration and writes out a .vtu with coilcurrent of zero.
Code: Select all
MAIN: -------------------------------------
MAIN: Steady state iteration: 1
MAIN: -------------------------------------
MAIN:
ComputeChange: SS (ITER=1) (NRM,RELC): ( 0.0000000 0.0000000 ) :: coilsolver
ResultOutputSolver: -------------------------------------
ResultOutputSolver: Saving with prefix: coil_test
here's the core dump...
Code: Select all
JfixPotentialSolver: Computing fixing potential for given current density
WARNING:: JfixPotentialSolver: No Dirichlet conditions used to define Jfix level!
SolveLinearSystem: Solution trivially zero!
MGDynAssembly: Elapsed REAL time: 0.0588 (s)
Program received signal SIGSEGV: Segmentation fault - invalid memory reference.
Backtrace for this error:
#0 0x7f76c1303960 in ???
#1 0x7f76c1302ac5 in ???
#2 0x7f76c10f951f in ???
#3 0x7f76c163118e in __lists_MOD_listfind
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/Lists.F90:2071
#4 0x7f76c1633cf4 in __lists_MOD_listgetinteger
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/Lists.F90:3918
#5 0x7f76c1a3fb33 in __defutils_MOD_getinteger
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/DefUtils.F90:1101
#6 0x7f76c1b38594 in __circuitutils_MOD_getcomponentparams
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/CircuitUtils.F90:117
#7 0x7f76b60cf991 in dosolve
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/modules/MagnetoDynamics/WhitneyAVSolver.F90:1077
#8 0x7f76b60da6f0 in whitneyavsolver_
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/modules/MagnetoDynamics/WhitneyAVSolver.F90:638
#9 0x7f76c18a1217 in __mainutils_MOD_singlesolver
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/MainUtils.F90:5266
#10 0x7f76c18b6d9e in __mainutils_MOD_solveractivate
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/MainUtils.F90:5609
#11 0x7f76c18b8b01 in solvecoupled
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/MainUtils.F90:3240
#12 0x7f76c18b9f8a in __mainutils_MOD_solveequations
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/MainUtils.F90:2936
#13 0x7f76c1b55144 in execsimulation
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/ElmerSolver.F90:3301
#14 0x7f76c1b5c8a8 in elmersolver_
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/ElmerSolver.F90:664
#15 0x5643c3a6d3f0 in solver
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/Solver.F90:57
#16 0x5643c3a6d15e in main
at /build/elmerfem-csc-qDPeYK/elmerfem-csc-9.0-0ppa0/fem/src/Solver.F90:34
Segmentation fault (core dumped)
Re: WhitneyAV / Solution trivially zero!
Posted: 18 Mar 2024, 20:20
by kevinarden
I do not have that problem. Using your mesh coil_test.msh and your sif coil_test_simplified.sif
I get a solution coil current = to 1, which is the default
Re: WhitneyAV / Solution trivially zero!
Posted: 19 Mar 2024, 18:11
by c0d3runn3r
Update 1 - it looks like CoilSolver will not solve for coilcurrent unless all bodies have defined materials. When I add materials back in for air and core, I get results
Update 2 - Gmsh uses 1-based body indices, Elmer uses zero based. Hence the segfault when I tried to use Gmsh body numbers.
Problem solved!
- core.png
- (754.46 KiB) Not downloaded yet