"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c

:link(lws,http://lammps.sandia.gov)
:link(ld,Manual.html)
:link(lc,Section_commands.html#comm)

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fix edpd/source command :h3
fix tdpd/source command :h3

[Syntax:]

fix ID group-ID edpd/source keyword values ...
fix ID group-ID tdpd/source cc_index keyword values ... :pre

ID, group-ID are documented in "fix"_fix.html command :ulb,l
edpd/source or tdpd/source = style name of this fix command :l
index (only specified for tdpd/source) = index of chemical species (1 to Nspecies) :l
keyword = {sphere} or {cuboid} :l
  {sphere} values = 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 lower left corner 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) :pre
:ule

[Examples:]

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 :pre

[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 "(Li2014)"_#Li2014b)
or diffusion with a source term (see Fig.1 in "(Li2015)"_#Li2015b), as
an analog of a periodic Poiseuille flow problem.

If the {sphere} keyword is used, the {cx,cy,cz,radius} defines a
spherical domain to apply the source flux to.

If the {cuboid} keyword is used, the {cx,cy,cz,dLx,dLy,dLz} defines a
cuboid domain to apply the source flux to.

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[Restart, fix_modify, output, run start/stop, minimize info:]

No information about this fix is written to "binary restart
files"_restart.html.  None of the "fix_modify"_fix_modify.html options
are relevant to this fix.  No global or per-atom quantities are stored
by this fix for access by various "output
commands"_Section_howto.html#howto_15.  No parameter of this fix can
be used with the {start/stop} keywords of the "run"_run.html command.
This fix is not invoked during "energy minimization"_minimize.html.

[Restrictions:]

This fix is part of the USER-MESO package. It is only enabled if
LAMMPS was built with that package. See the "Making
LAMMPS"_Section_start.html#start_3 section for more info.

Fix {edpd/source} must be used with the "pair_style
edpd"_pair_meso.html command.  Fix {tdpd/source} must be used with the
"pair_style tdpd"_pair_meso.html command.

[Related commands:]

"pair_style edpd"_pair_meso.html, "pair_style tdpd"_pair_meso.html,
"compute edpd/temp/atom"_compute_edpd_temp_atom.html, "compute
tdpd/cc/atom"_compute_tdpd_cc_atom.html

[Default:] none

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:link(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

:link(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
