129 lines
4.5 KiB
ReStructuredText
129 lines
4.5 KiB
ReStructuredText
.. index:: fix edpd/source
|
|
.. index:: fix tdpd/source
|
|
|
|
fix edpd/source command
|
|
=======================
|
|
|
|
fix tdpd/source command
|
|
=======================
|
|
|
|
Syntax
|
|
""""""
|
|
|
|
.. code-block:: LAMMPS
|
|
|
|
fix ID group-ID edpd/source keyword values ...
|
|
fix ID group-ID tdpd/source cc_index keyword values ...
|
|
|
|
* ID, group-ID are documented in :doc:`fix <fix>` command
|
|
* edpd/source or tdpd/source = style name of this fix command
|
|
* index (only specified for tdpd/source) = index of chemical species (1 to Nspecies)
|
|
* keyword = *sphere* or *cuboid* or *region*
|
|
|
|
.. parsed-literal::
|
|
|
|
*sphere* args = cx cy cz radius source
|
|
cx,cy,cz = x,y,z center of spherical domain (distance units)
|
|
radius = radius of a spherical domain (distance units)
|
|
source = heat source or concentration source (flux units, see below)
|
|
*cuboid* values = cx cy cz dLx dLy dLz source
|
|
cx,cy,cz = x,y,z center of a cuboid domain (distance units)
|
|
dLx,dLy,dLz = x,y,z side length of a cuboid domain (distance units)
|
|
source = heat source or concentration source (flux units, see below)
|
|
*region* values = region-ID source
|
|
region = ID of region for heat or concentration source
|
|
source = heat source or concentration source (flux units, see below)
|
|
|
|
Examples
|
|
""""""""
|
|
|
|
.. code-block:: LAMMPS
|
|
|
|
fix 1 all edpd/source sphere 0.0 0.0 0.0 5.0 0.01
|
|
fix 1 all edpd/source cuboid 0.0 0.0 0.0 20.0 10.0 10.0 -0.01
|
|
fix 1 all tdpd/source 1 sphere 5.0 0.0 0.0 5.0 0.01
|
|
fix 1 all tdpd/source 2 cuboid 0.0 0.0 0.0 20.0 10.0 10.0 0.01
|
|
fix 1 all tdpd/source 1 region lower -0.01
|
|
|
|
Description
|
|
"""""""""""
|
|
|
|
Fix *edpd/source* adds a heat source as an external heat flux to each
|
|
atom in a spherical or cuboid domain, where the *source* is in units
|
|
of energy/time. Fix *tdpd/source* adds an external concentration
|
|
source of the chemical species specified by *index* as an external
|
|
concentration flux for each atom in a spherical or cuboid domain,
|
|
where the *source* is in units of mole/volume/time.
|
|
|
|
This command can be used to give an additional heat/concentration
|
|
source term to atoms in a simulation, such as for a simulation of a
|
|
heat conduction with a source term (see Fig.12 in :ref:`(Li2014) <Li2014b>`)
|
|
or diffusion with a source term (see Fig.1 in :ref:`(Li2015) <Li2015b>`), as
|
|
an analog of a periodic Poiseuille flow problem.
|
|
|
|
.. deprecated:: 15Jun2023
|
|
|
|
The *sphere* and *cuboid* keywords will be removed in a future version
|
|
of LAMMPS. The same functionality and more can be achieved with a region.
|
|
|
|
If the *sphere* keyword is used, the *cx, cy, cz, radius* values define
|
|
a spherical domain to apply the source flux to.
|
|
|
|
If the *cuboid* keyword is used, the *cx, cy, cz, dLx, dLy, dLz* define
|
|
a cuboid domain to apply the source flux to.
|
|
|
|
If the *region* keyword is used, the *region-ID* selects which
|
|
:doc:`region <region>` to apply the source flux to.
|
|
|
|
----------
|
|
|
|
Restart, fix_modify, output, run start/stop, minimize info
|
|
"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
|
|
|
|
No information of these fixes is written to :doc:`binary restart files
|
|
<restart>`. None of the :doc:`fix_modify <fix_modify>` options are
|
|
relevant to these fixes. No global or per-atom quantities are stored by
|
|
these fixes for access by various :doc:`output commands <Howto_output>`.
|
|
No parameter of these fixes can be used with the *start/stop* keywords
|
|
of the :doc:`run <run>` command. These fixes are not invoked during
|
|
:doc:`energy minimization <minimize>`.
|
|
|
|
Restrictions
|
|
""""""""""""
|
|
|
|
These fixes are part of the DPD-MESO package. They are only enabled if
|
|
LAMMPS was built with that package. See the :doc:`Build package
|
|
<Build_package>` page for more info.
|
|
|
|
Fix *edpd/source* must be used with the :doc:`pair_style edpd
|
|
<pair_mesodpd>` command. Fix *tdpd/source* must be used with the
|
|
:doc:`pair_style tdpd <pair_mesodpd>` command.
|
|
|
|
Related commands
|
|
""""""""""""""""
|
|
|
|
:doc:`pair_style edpd <pair_mesodpd>`, :doc:`pair_style tdpd <pair_mesodpd>`,
|
|
:doc:`compute edpd/temp/atom <compute_edpd_temp_atom>`,
|
|
:doc:`compute tdpd/cc/atom <compute_tdpd_cc_atom>`
|
|
|
|
Default
|
|
"""""""
|
|
|
|
none
|
|
|
|
----------
|
|
|
|
.. _Li2014b:
|
|
|
|
**(Li2014)** Z. Li, Y.-H. Tang, H. Lei, B. Caswell and G.E. Karniadakis,
|
|
"Energy-conserving dissipative particle dynamics with
|
|
temperature-dependent properties", J. Comput. Phys., 265: 113-127
|
|
(2014). DOI: 10.1016/j.jcp.2014.02.003
|
|
|
|
.. _Li2015b:
|
|
|
|
**(Li2015)** Z. Li, A. Yazdani, A. Tartakovsky and G.E. Karniadakis,
|
|
"Transport dissipative particle dynamics model for mesoscopic
|
|
advection-diffusion-reaction problems", J. Chem. Phys., 143: 014101
|
|
(2015). DOI: 10.1063/1.4923254
|