mirror of https://github.com/lammps/lammps.git
71 lines
2.2 KiB
Plaintext
71 lines
2.2 KiB
Plaintext
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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/taitwater/morris command :h3
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[Syntax:]
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pair_style sph/taitwater/morris :pre
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[Examples:]
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pair_style sph/taitwater/morris
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pair_coeff * * 1000.0 1430.0 1.0 2.4
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[Description:]
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The sph/taitwater/morris style computes pressure forces between particles according to Tait's equation of state,
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\begin{equation}
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p = B [(\frac{\rho}{\rho_0})^{\gamma} - 1],
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\end{equation}
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where $\gamma=7$ and $B=c_0^2 \rho_0 / \gamma$, with $\rho_0$ being the reference density and $c_0$ the reference speed of sound.
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This pair style also computes laminar viscosity (Morris1997).
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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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rho0 reference density (mass/volume units)
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c0 reference soundspeed (distance/time units)
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nu dynamic viscosity (mass*distance/time units)
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h kernel function cutoff (distance units)
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:line
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[Mixing, shift, table, tail correction, restart, rRESPA info]:
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These pair styles do not support mixing. Thus, coefficients for all
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I,J pairs must be specified explicitly. Additionally, because rho0 and c0 are defined on a per-type basis,
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an I,I as well a J,J coefficients line must be specified prior to specifying an I,J interaction.
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This style does not write information to "binary restart
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files"_restart.html, so pair_style and pair_coeff commands do need
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to be specified in an input script that reads a restart file.
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These styles can only be used via the {pair} keyword of the "run_style
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respa"_run_style.html command. They do not support the {inner},
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{middle}, {outer} keywords.
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[Restrictions:]
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The {pair sph/taitwater/morris} style is part of the "USER-SPH" package. It is
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only enabled if LAMMPS was built with that package (which it is by
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default). See the "Making LAMMPS"_Section_start.html#2_3 section for
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more info.
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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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[(Morris1997)] J.P. Morris, P.J. Fox, and Y. Zhu. Modeling Low Reynolds Number Incompressible Flows Using SPH. Journal of Computational Physics, 136:214–226, 1997.
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