mirror of https://github.com/lammps/lammps.git
86 lines
1.8 KiB
Plaintext
86 lines
1.8 KiB
Plaintext
.. index:: compute dpd
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compute dpd command
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===================
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Syntax
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""""""
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.. parsed-literal::
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compute ID group-ID dpd
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* ID, group-ID are documented in :doc:`compute <compute>` command
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* dpd = style name of this compute command
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Examples
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""""""""
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.. parsed-literal::
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compute 1 all dpd
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Description
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"""""""""""
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Define a computation that accumulates the total internal conductive
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energy (U_cond), the total internal mechanical energy (U_mech), the
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total chemical energy (U_chem) and the *harmonic* average of the internal
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temperature (dpdTheta) for the entire system of particles. See the
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:doc:`compute dpd/atom <compute_dpd_atom>` command if you want
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per-particle internal energies and internal temperatures.
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The system internal properties are computed according to the following
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relations:
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.. image:: Eqs/compute_dpd.jpg
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:align: center
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where N is the number of particles in the system
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----------
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**Output info:**
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This compute calculates a global vector of length 5 (U_cond, U_mech,
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U_chem, dpdTheta, N_particles), which can be accessed by indices 1-5. See
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:ref:`this section <howto_15>` for an overview of LAMMPS
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output options.
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The vector values will be in energy and temperature :doc:`units <units>`.
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Restrictions
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""""""""""""
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The compute *dpd* is only available if LAMMPS is built with the
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USER-DPD package and requires the :doc:`atom_style dpd <atom_style>`.
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Related commands
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""""""""""""""""
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:doc:`compute dpd/atom <compute_dpd_atom>`,
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:doc:`thermo_style <thermo_style>`
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**Default:** none
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----------
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.. _Larentzos:
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**(Larentzos)** J.P. Larentzos, J.K. Brennan, J.D. Moore, and
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W.D. Mattson, "LAMMPS Implementation of Constant Energy Dissipative
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Particle Dynamics (DPD-E)", ARL-TR-6863, U.S. Army Research
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Laboratory, Aberdeen Proving Ground, MD (2014).
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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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