CFDEMCoupling & Servo Wall

Hi there,

i try to run a coupled simulation with servo wall pushing on some kind of particle column. An overview of the geometry is give in the attached screen shots. Actually, the particles are within a pipe, but for the sake of visibility this is not shown in the overview. The red circular face is the servo wall. The fluid region is meshed with snappy.
Running the simulation in DEM only is done without problems, however the coupled run dies at the first DEM run. From the log-file it seems that the mesh/surface/stress/servo makes some problems:

.....
#screen output
compute 1 all erotate/sphere
thermo_style custom step atoms ke c_1 vol c_centerOfMass[3] #c_dragtotal[1] c_dragtotal[2] c_dragtotal[3]
thermo 1000
thermo_modify lost ignore norm no
compute_modify thermo_temp dynamic yes
#insert the first particles so that dump is not empty
dump dumpServo all stl 500 ../DEM/post/melting/dumpservo*.stl servo
dump dmp all custom 500 ../DEM/post/melting/dump_restart_*.liggghts id type type x y z ix iy iz vx vy vz fx fy fz omegax omegay omegaz radius f_Temp[0] f_heatFlux[0] f_heatSource[0]
run 1
Resetting global state of Fix contacthistory Style contacthistory from restart file info
Resetting per-atom state of Fix contacthistory Style contacthistory from restart file info
[0] #0 Foam::error::printStack(Foam::Ostream&)[1] #0 Foam::error::printStack(Foam::Ostream&) at ??:?
[0] #1 Foam::sigSegv::sigHandler(int) at ??:?
[1] #1 Foam::sigSegv::sigHandler(int) at ??:?
[0] #2 at ??:?
[1] #2 in "/lib/x86_64-linux-gnu/libc.so.6"
[0] #3 LAMMPS_NS::FixMeshSurfaceStressServo::getMaxRad() in "/lib/x86_64-linux-gnu/libc.so.6"
[1] #3 LAMMPS_NS::FixMeshSurfaceStressServo::getMaxRad() at ??:?
[1] #4 LAMMPS_NS::FixMeshSurfaceStressServo::init() at ??:?
[0] #4 LAMMPS_NS::FixMeshSurfaceStressServo::init() at ??:?
[1] #5 LAMMPS_NS::Modify::init() at ??:?
[0] #5 LAMMPS_NS::Modify::init() at ??:?
[0] #6 LAMMPS_NS::LAMMPS::init() at ??:?
[1] #6 LAMMPS_NS::LAMMPS::init() at ??:?
[0] #7 LAMMPS_NS::Run::command(int, char**) at ??:?
[1] #7 LAMMPS_NS::Run::command(int, char**) at ??:?
[0] #8 void LAMMPS_NS::Input::command_creator(LAMMPS_NS::LAMMPS*, int, char**) at ??:?
[1] #8 void LAMMPS_NS::Input::command_creator(LAMMPS_NS::LAMMPS*, int, char**) at ??:?
[1] #9 LAMMPS_NS::Input::execute_command() at ??:?
[0] #9 LAMMPS_NS::Input::execute_command() at ??:?
[0] #10 LAMMPS_NS::Input::file() at ??:?
[1] #10 LAMMPS_NS::Input::file() at ??:?
[0] #11 LAMMPS_NS::Input::file(char const*) at ??:?
[1] #11 LAMMPS_NS::Input::file(char const*) at ??:?
[0] #12 Foam::twoWayMPI::twoWayMPI(Foam::dictionary const&, Foam::cfdemCloud&) at ??:?
[1] #12 Foam::twoWayMPI::twoWayMPI(Foam::dictionary const&, Foam::cfdemCloud&) at ??:?
[1] #13 Foam::dataExchangeModel::adddictionaryConstructorToTable::New(Foam::dictionary const&, Foam::cfdemCloud&) at ??:?
[0] #13 Foam::dataExchangeModel::adddictionaryConstructorToTable::New(Foam::dictionary const&, Foam::cfdemCloud&) at ??:?
[1] #14 Foam::dataExchangeModel::New(Foam::dictionary const&, Foam::cfdemCloud&) at ??:?
[0] #14 Foam::dataExchangeModel::New(Foam::dictionary const&, Foam::cfdemCloud&) at ??:?
[1] #15 Foam::cfdemCloud::cfdemCloud(Foam::fvMesh const&) at ??:?
[0] #15 Foam::cfdemCloud::cfdemCloud(Foam::fvMesh const&) at ??:?
[1] #16
at ??:?
[0] #16 [1] at ??:?
[1] #17 __libc_start_main
in "/lib/x86_64-linux-gnu/libc.so.6"
[1] #18 [0] at ??:?
[0] #17 __libc_start_main
[1] at ??:?
[Bernoulli:05984] *** Process received signal ***
[Bernoulli:05984] Signal: Segmentation fault (11)
[Bernoulli:05984] Signal code: (-6)
[Bernoulli:05984] Failing at address: 0x3e800001760
in "/lib/x86_64-linux-gnu/libc.so.6"
[0] #18 [Bernoulli:05984] [ 0] /lib/x86_64-linux-gnu/libc.so.6(+0x36cb0) [0x7fc791325cb0]
[Bernoulli:05984] [ 1] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0x37) [0x7fc791325c37]
[Bernoulli:05984] [ 2] /lib/x86_64-linux-gnu/libc.so.6(+0x36cb0) [0x7fc791325cb0]
[Bernoulli:05984] [ 3] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN9LAMMPS_NS25FixMeshSurfaceStressServo9getMaxRadEv+0xc7) [0x7fc792f30c17]
[Bernoulli:05984] [ 4] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN9LAMMPS_NS25FixMeshSurfaceStressServo4initEv+0x82) [0x7fc792f31e82]
[Bernoulli:05984] [ 5] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN9LAMMPS_NS6Modify4initEv+0x248) [0x7fc793216ef8]
[Bernoulli:05984] [ 6] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN9LAMMPS_NS6LAMMPS4initEv+0x33) [0x7fc7931e2b13]
[Bernoulli:05984] [ 7] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN9LAMMPS_NS3Run7commandEiPPc+0x7b2) [0x7fc7932ffb02]
[Bernoulli:05984] [ 8] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN9LAMMPS_NS5Input15command_creatorINS_3RunEEEvPNS_6LAMMPSEiPPc+0x28) [0x7fc7931d8068]
[Bernoulli:05984] [ 9] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN9LAMMPS_NS5Input15execute_commandEv+0x880) [0x7fc7931d5dc0]
[Bernoulli:05984] [10] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN9LAMMPS_NS5Input4fileEv+0x4f8) [0x7fc7931d6818]
[Bernoulli:05984] [11] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN9LAMMPS_NS5Input4fileEPKc+0x9b) [0x7fc7931d69ab]
[Bernoulli:05984] [12] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN4Foam9twoWayMPIC2ERKNS_10dictionaryERNS_10cfdemCloudE+0x6cb) [0x7fc792d3b23b]
[Bernoulli:05984] [13] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN4Foam17dataExchangeModel31adddictionaryConstructorToTableINS_9twoWayMPIEE3NewERKNS_10dictionaryERNS_10cfdemCloudE+0x2e) [0x7fc792d3bc2e]
[Bernoulli:05984] [14] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN4Foam17dataExchangeModel3NewERKNS_10dictionaryERNS_10cfdemCloudE+0x385) [0x7fc792d34195]
[Bernoulli:05984] [15] /home/ak113859/OpenFOAM/ak113859-2.2.0/platforms/linux64GccDPOpt/lib/liblagrangianCFDEM-IPIM-2.2.0.so(_ZN4Foam10cfdemCloudC2ERKNS_6fvMeshE+0x657) [0x7fc792c84e47]
[Bernoulli:05984] [16] cfdemSolverInterDyMPC() [0x42d7cb]
[Bernoulli:05984] [17] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5) [0x7fc791310f45]
[Bernoulli:05984] [18] cfdemSolverInterDyMPC() [0x43735a]
[Bernoulli:05984] *** End of error message ***


So before i try to investigate this problem just a few general questions:

1.) Is the fix mesh/surface/stress/servo compatible with CFDEM Coupling or DEM only? (As much as i had seen in the forum it should work in the coupling too, right?)

2.) As it can been seen in the screenshots, not all particles are within the fluid domain. Is this allowed or may it lead to problems?

3.) Assume that there are much less particles in the column so that the servo wall is inside the fluid domain. This should not be a problem as the CFD part of the simulation doesn't know anything about the wall. Is this correct?

That's it for the moment. Thank you in advance and best regards,

Klaus