2011-08-28 04:09:27 +08:00
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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
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:link(lws,http://lammps.sandia.gov)
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:link(ld,Manual.html)
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:link(lc,Section_commands.html#comm)
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:line
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pair_style sph/idealgas command :h3
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[Syntax:]
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pair_style sph/idealgas :pre
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[Examples:]
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pair_style sph/idealgas
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2011-08-28 05:11:46 +08:00
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pair_coeff * * 1.0 2.4 :pre
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2011-08-28 04:09:27 +08:00
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[Description:]
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2011-08-28 05:11:46 +08:00
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The sph/idealgas style computes pressure forces between particles
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according to the ideal gas equation of state:
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2011-08-28 05:18:57 +08:00
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:c,image(Eqs/pair_sph_ideal.jpg)
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2011-08-28 04:09:27 +08:00
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2011-08-28 05:11:46 +08:00
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where gamma = 1.4 is the heat capacity ratio, rho is the local
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density, and e is the internal energy per unit mass. This pair style
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also computes Monaghan's artificial viscosity to prevent particles
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from interpentrating "(Monaghan)"_#Monoghan.
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See "this PDF guide"_USER/sph/SPH_LAMMPS_userguide.pdf to using SPH in
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LAMMPS.
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2011-08-28 04:09:27 +08:00
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The following coefficients must be defined for each pair of atoms
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types via the "pair_coeff"_pair_coeff.html command as in the examples
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above.
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nu artificial viscosity (no units)
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2011-08-28 05:11:46 +08:00
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h kernel function cutoff (distance units) :ul
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2011-08-28 04:09:27 +08:00
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:line
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[Mixing, shift, table, tail correction, restart, rRESPA info]:
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2011-08-28 05:11:46 +08:00
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This style does not support mixing. Thus, coefficients for all
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2011-08-28 04:09:27 +08:00
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I,J pairs must be specified explicitly.
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2011-08-28 05:11:46 +08:00
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This style does not support the "pair_modify"_pair_modify.html
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shift, table, and tail options.
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2011-08-28 04:09:27 +08:00
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This style does not write information to "binary restart
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2011-08-28 05:11:46 +08:00
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files"_restart.html. Thus, you need to re-specify the pair_style and
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pair_coeff commands in an input script that reads a restart file.
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2011-08-28 04:09:27 +08:00
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2011-08-28 05:11:46 +08:00
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This style can only be used via the {pair} keyword of the "run_style
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respa"_run_style.html command. It does not support the {inner},
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2011-08-28 04:09:27 +08:00
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{middle}, {outer} keywords.
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[Restrictions:]
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2011-08-28 05:11:46 +08:00
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This pair style is part of the USER-SPH package. It is only enabled
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if LAMMPS was built with that package. See the "Making
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LAMMPS"_Section_start.html#start_3 section for more info.
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2011-08-28 04:09:27 +08:00
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[Related commands:]
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"pair_coeff"_pair_coeff.html, pair_sph/rhosum
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[Default:] none
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2011-08-28 05:11:46 +08:00
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:line
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:link(Monoghan)
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[(Monaghan)] Monaghan and Gingold, Journal of Computational Physics,
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52, 374-389 (1983).
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2011-08-28 04:09:27 +08:00
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