forked from lijiext/lammps
68 lines
1.8 KiB
Plaintext
68 lines
1.8 KiB
Plaintext
.. index:: compute smd/tlsph/dt
|
|
|
|
compute smd/tlsph/dt command
|
|
============================
|
|
|
|
Syntax
|
|
""""""
|
|
|
|
.. parsed-literal::
|
|
|
|
compute ID group-ID smd/tlsph/dt
|
|
|
|
* ID, group-ID are documented in :doc:`compute <compute>` command
|
|
* smd/tlsph/dt = style name of this compute command
|
|
|
|
Examples
|
|
""""""""
|
|
|
|
.. parsed-literal::
|
|
|
|
compute 1 all smd/tlsph/dt
|
|
|
|
Description
|
|
"""""""""""
|
|
|
|
Define a computation that outputs the CFL-stable time increment per
|
|
particle. This time increment is essentially given by the speed of
|
|
sound, divided by the SPH smoothing length. Because both the speed of
|
|
sound and the smoothing length typically change during the course of a
|
|
simulation, the stable time increment needs to be recomputed every
|
|
time step. This calculation is performed automatically in the
|
|
relevant SPH pair styles and this compute only serves to make the
|
|
stable time increment accessible for output purposes.
|
|
|
|
See `this PDF guide <USER/smd/SMD_LAMMPS_userguide.pdf>`_ to using 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 values will be given in :doc:`units <units>` of time.
|
|
|
|
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 compute can only be used for particles interacting with the
|
|
Total-Lagrangian SPH pair style.
|
|
|
|
Related commands
|
|
""""""""""""""""
|
|
|
|
:doc:`smd/adjust/dt <fix_smd_adjust_dt>`
|
|
|
|
**Default:** none
|
|
|
|
|
|
.. _lws: http://lammps.sandia.gov
|
|
.. _ld: Manual.html
|
|
.. _lc: Section_commands.html#comm
|