Where is a problem ? (newbie)

Hi,
I am new in this field of investigation, so I am trying to do some modifications in LIGGGHTS examples. My goal is to use DEM and CFD for modelling of the Shaft furnace for raw material thermal treatment.

I will be thankful for any advice (or better, for correction of attached code)

I will be also very thankful if anybody send me more of yours own examples or advices how to effectively learn use this tools. (pavol.palicka@tuke.sk)

Best regards
Paul

Here is LIGGGHTS output of my existing problem:

pavol@pavol:~/LIGGGHTS-PUBLIC/examples/LIGGGHTS/Tutorials_public/meshGran_02$ mpirun -np 8 liggghts -in in.meshGran_02
LIGGGHTS (Version LIGGGHTS-PUBLIC 2.3.8, compiled 2014-07-02-17:07:55 by root based on LAMMPS 20 Apr 2012)
Created orthogonal box = (-5 -2 -4) to (1 2 1.5)
2 by 2 by 2 MPI processor grid

Reading STL file 'vnutro.stl'

Reading STL file 'poklop.stl'
Fix particledistribution/discrete (id pdd1): distribution based on mass%:
pts1: d=1.000000e-02 (max. bounding sphere) mass%=100.000000%
Fix particledistribution/discrete (id pdd1): distribution based on number%:
pts1: d=1.000000e-02 (max. bounding sphere) number%=100.000000%
0 atoms in group nve_group
Setting up run ...
Mesh cad: 992 elements have high aspect ratio (angle < 0.500000 °)
WARNING: Fix mesh: Mesh contains highly skewed element, moving mesh (if used) will not parallelize well (surface_mesh_I.h:484)
ERROR: Mesh cad: The minumum angle of mesh element 1981 (line 13869) is lower than the specified curvature. Increase mesh quality or decrease curvature (currently 0.256235°)
ERROR on proc 5: Fix mesh: Bad mesh, cannot continue. You can try setting 'curvature' to 1e-5 or lower (surface_mesh_I.h:475)
--------------------------------------------------------------------------
MPI_ABORT was invoked on rank 5 in communicator MPI_COMM_WORLD
with errorcode 1.

NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes.
You may or may not see output from other processes, depending on
exactly when Open MPI kills them.
--------------------------------------------------------------------------
ERROR: Mesh cad: The minumum angle of mesh element 1983 (line 13883) is lower than the specified curvature. Increase mesh quality or decrease curvature (currently 0.256235°)
ERROR on proc 7: Fix mesh: Bad mesh, cannot continue. You can try setting 'curvature' to 1e-5 or lower (surface_mesh_I.h:475)
--------------------------------------------------------------------------
mpirun has exited due to process rank 5 with PID 6464 on
node pavol exiting without calling "finalize". This may
have caused other processes in the application to be
terminated by signals sent by mpirun (as reported here).
--------------------------------------------------------------------------
[pavol:06458] 1 more process has sent help message help-mpi-api.txt / mpi-abort
[pavol:06458] Set MCA parameter "orte_base_help_aggregate" to 0 to see all help / error messages