94 lines
2.3 KiB
ReStructuredText
94 lines
2.3 KiB
ReStructuredText
.. index:: pair_style sph/lj
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.. index:: pair_style sph/lj/gpu
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pair_style sph/lj command
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=========================
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Accelerator Variants: *sph/lj/gpu*
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Syntax
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""""""
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.. code-block:: LAMMPS
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pair_style sph/lj
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Examples
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""""""""
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.. code-block:: LAMMPS
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pair_style sph/lj
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pair_coeff * * 1.0 2.4
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Description
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"""""""""""
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The sph/lj style computes pressure forces between particles according
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to the Lennard-Jones equation of state, which is computed according to
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Ree's 1980 polynomial fit :ref:`(Ree) <Ree>`. The Lennard-Jones parameters
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epsilon and sigma are set to unity. This pair style also computes
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Monaghan's artificial viscosity to prevent particles from
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interpenetrating :ref:`(Monaghan) <Monoghan>`.
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See `this PDF guide <PDF/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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* :math:`\nu` artificial viscosity (no units)
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* h kernel function cutoff (distance units)
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----------
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.. include:: accel_styles.rst
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----------
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Mixing, shift, table, tail correction, restart, rRESPA info
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"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
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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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As noted above, the Lennard-Jones parameters epsilon and sigma are set
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to unity.
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This pair style is part of the SPH package. It is only enabled
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if LAMMPS was built with that package. See the :doc:`Build package <Build_package>` page 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
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"""""""
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none
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----------
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.. _Ree:
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**(Ree)** Ree, Journal of Chemical Physics, 73, 5401 (1980).
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.. _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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