forked from lijiext/lammps
71 lines
1.9 KiB
Plaintext
71 lines
1.9 KiB
Plaintext
|
.. index:: compute smd/hourglass/error
|
||
|
|
|
||
|
|
compute smd/hourglass/error command
|
||
|
|
===================================
|
||
|
|
|
||
|
|
Syntax
|
||
|
|
""""""
|
||
|
|
|
||
|
|
.. parsed-literal::
|
||
|
|
|
||
|
|
compute ID group-ID smd/hourglass/error
|
||
|
|
|
||
|
|
* ID, group-ID are documented in :doc:`compute <compute>` command
|
||
|
|
* smd/hourglass/error = style name of this compute command
|
||
|
|
|
||
|
|
Examples
|
||
|
|
""""""""
|
||
|
|
|
||
|
|
.. parsed-literal::
|
||
|
|
|
||
|
|
compute 1 all smd/hourglass/error
|
||
|
|
|
||
|
|
Description
|
||
|
|
"""""""""""
|
||
|
|
|
||
|
|
Define a computation which outputs the error of the approximated
|
||
|
|
relative separation with respect to the actual relative separation of
|
||
|
|
the particles i and j. Ideally, if the deformation gradient is exact,
|
||
|
|
and there exists a unique mapping between all particles' positions
|
||
|
|
within the neighborhood of the central node and the deformation
|
||
|
|
gradient, the approximated relative separation will coincide with the
|
||
|
|
actual relative separation of the particles i and j in the deformed
|
||
|
|
configuration. This compute is only really useful for debugging the
|
||
|
|
hourglass control mechanim which is part of the Total-Lagrangian SPH
|
||
|
|
pair style.
|
||
|
|
|
||
|
|
See `this PDF guide <USER/smd/SMD_LAMMPS_userguide.pdf>`_ to use Smooth
|
||
|
|
Mach Dynamics in LAMMPS.
|
||
|
|
|
||
|
|
**Output Info:**
|
||
|
|
|
||
|
|
This compute calculates a per-particle vector, which can be accessed by
|
||
|
|
any command that uses per-particle values from a compute as input. See
|
||
|
|
:ref:`How-to discussions, section 6.15 <howto_15>`
|
||
|
|
for an overview of LAMMPS output options.
|
||
|
|
|
||
|
|
The per-particle vector values will are dimensionless. See
|
||
|
|
:doc:`units <units>`.
|
||
|
|
|
||
|
|
Restrictions
|
||
|
|
""""""""""""
|
||
|
|
|
||
|
|
|
||
|
|
This compute is part of the USER-SMD package. It is only enabled if
|
||
|
|
LAMMPS was built with that package. See the :ref:`Making LAMMPS <start_3>` section for more info.
|
||
|
|
|
||
|
|
This quantity will be computed only for particles which interact with
|
||
|
|
tlsph pair style.
|
||
|
|
|
||
|
|
**Related Commands:**
|
||
|
|
|
||
|
|
:doc:`smd/tlsph_defgrad <compute_smd_tlsph_defgrad>`
|
||
|
|
|
||
|
|
Default
|
||
|
|
"""""""
|
||
|
|
|
||
|
|
|
||
|
|
.. _lws: http://lammps.sandia.gov
|
||
|
|
.. _ld: Manual.html
|
||
|
|
.. _lc: Section_commands.html#comm
|