forked from lijiext/lammps
72 lines
2.1 KiB
Plaintext
72 lines
2.1 KiB
Plaintext
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.. index:: fix smd/integrate_ulsph
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fix smd/integrate_ulsph command
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===============================
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Syntax
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""""""
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.. parsed-literal::
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fix ID group-ID smd/integrate_ulsph keyword
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* ID, group-ID are documented in :doc:`fix <fix>` command
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* smd/integrate_ulsph = style name of this fix command
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* zero or more keyword/value pairs may be appended
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keyword = adjust_radius or limit_velocity
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adjust_radius values = adjust_radius_factor min_nn max_nn
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adjust_radius_factor = factor which scale the smooth/kernel radius
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min_nn = minimum number of neighbors
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max_nn = maximum number of neighbors
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limit_velocity values = max_velocity
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max_velocity = maximum allowed velocity.
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Examples
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""""""""
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.. parsed-literal::
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fix 1 all smd/integrate_ulsph adjust_radius 1.02 25 50
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.. parsed-literal::
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fix 1 all smd/integrate_ulsph limit_velocity 1000
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Description
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"""""""""""
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The fix performs explicit time integration for particles which interact with the updated Lagrangian SPH pair style.
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See `this PDF guide <USER/smd/SMD_LAMMPS_userguide.pdf>`_ to using Smooth Mach Dynamics in LAMMPS.
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The *adjust_radius* keyword activates dynamic adjustment of the per-particle SPH smoothing kernel radius such that the number of neighbors per particles remains
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within the interval *min_nn* to *max_nn*\ . The parameter *adjust_radius_factor* determines the amount of adjustment per timestep. Typical values are
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*adjust_radius_factor*\ =1.02, *min_nn*\ =15, and *max_nn*\ =20.
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The *limit_velocity* keyword will control the velocity, scaling the norm of
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the velocity vector to max_vel in case it exceeds this velocity limit.
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Restart, fix_modify, output, run start/stop, minimize info
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""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
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Currently, no part of USER-SMD supports restarting nor minimization. This fix has no outputs.
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Restrictions
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""""""""""""
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This fix is part of the USER-SMD package. It is only enabled if
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LAMMPS was built with that package. See the :ref:`Making LAMMPS <start_3>`
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section for more info.
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Related commands
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""""""""""""""""
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**Default:** none
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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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