forked from lijiext/lammps
95 lines
2.2 KiB
Plaintext
95 lines
2.2 KiB
Plaintext
.. index:: pair_style sph/taitwater
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pair_style sph/taitwater command
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================================
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Syntax
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""""""
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.. parsed-literal::
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pair_style sph/taitwater
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Examples
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""""""""
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.. parsed-literal::
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pair_style sph/taitwater
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pair_coeff * * 1000.0 1430.0 1.0 2.4
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Description
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"""""""""""
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The sph/taitwater style computes pressure forces between SPH particles
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according to Tait's equation of state:
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.. image:: Eqs/pair_sph_tait.jpg
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:align: center
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where gamma = 7 and B = c_0^2 rho_0 / gamma, with rho_0 being the
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reference density and c_0 the reference speed of sound.
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This pair style also computes Monaghan's artificial viscosity to
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prevent particles from interpentrating :ref:`(Monaghan) <Monaghan>`.
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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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The following coefficients must be defined for each pair of atoms
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types via the :doc:`pair_coeff <pair_coeff>` command as in the examples
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above.
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* rho0 reference density (mass/volume units)
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* c0 reference soundspeed (distance/time units)
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* nu artificial viscosity (no units)
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* h kernel function cutoff (distance units)
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----------
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**Mixing, shift, table, tail correction, restart, rRESPA info**\ :
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This style does not support mixing. Thus, coefficients for all
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I,J pairs must be specified explicitly.
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This style does not support the :doc:`pair_modify <pair_modify>`
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shift, table, and tail options.
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This style does not write information to :doc:`binary restart files <restart>`. 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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This style can only be used via the *pair* keyword of the :doc:`run_style respa <run_style>` command. It does not support the *inner*\ ,
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*middle*\ , *outer* keywords.
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Restrictions
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""""""""""""
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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 :ref:`Making LAMMPS <start_3>` section for more info.
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Related commands
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""""""""""""""""
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:doc:`pair_coeff <pair_coeff>`, pair_sph/rhosum
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**Default:** none
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----------
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.. _Monaghan:
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**(Monaghan)** Monaghan and Gingold, Journal of Computational Physics,
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52, 374-389 (1983).
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.. _lws: http://lammps.sandia.gov
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.. _ld: Manual.html
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.. _lc: Section_commands.html#comm
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