forked from lijiext/lammps
114 lines
5.1 KiB
Plaintext
114 lines
5.1 KiB
Plaintext
"Previous Section"_Section_howto.html - "LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc - "Next Section"_Section_perf.html :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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7. Example problems :h3
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The LAMMPS distribution includes an examples sub-directory with
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several sample problems. Each problem is in a sub-directory of its
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own. Most are 2d models so that they run quickly, requiring at most a
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couple of minutes to run on a desktop machine. Each problem has an
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input script (in.*) and produces a log file (log.*) and dump file
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(dump.*) when it runs. Some use a data file (data.*) of initial
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coordinates as additional input. A few sample log file outputs on
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different machines and different numbers of processors are included in
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the directories to compare your answers to. E.g. a log file like
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log.crack.foo.P means it ran on P processors of machine "foo".
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For examples that use input data files, many of them were produced by
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"Pizza.py"_http://pizza.sandia.gov or setup tools described in the
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"Additional Tools"_Section_tools.html section of the LAMMPS
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documentation and provided with the LAMMPS distribution.
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If you uncomment the "dump"_dump.html command in the input script, a
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text dump file will be produced, which can be animated by various
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"visualization programs"_http://lammps.sandia.gov/viz.html. It can
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also be animated using the xmovie tool described in the "Additional
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Tools"_Section_tools.html section of the LAMMPS documentation.
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If you uncomment the "dump image"_dump.html command in the input
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script, and assuming you have built LAMMPS with a JPG library, JPG
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snapshot images will be produced when the simulation runs. They can
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be quickly post-processed into a movie using commands described on the
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"dump image"_dump_image.html doc page.
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Animations of many of these examples can be viewed on the Movies
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section of the "LAMMPS WWW Site"_lws.
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These are the sample problems in the examples sub-directories:
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body: body particles, 2d system
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colloid: big colloid particles in a small particle solvent, 2d system
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comb: models using the COMB potential
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crack: crack propagation in a 2d solid
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dipole: point dipolar particles, 2d system
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dreiding: methanol via Dreiding FF
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eim: NaCl using the EIM potential
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ellipse: ellipsoidal particles in spherical solvent, 2d system
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flow: Couette and Poiseuille flow in a 2d channel
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friction: frictional contact of spherical asperities between 2d surfaces
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gpu: use of the GPU package for GPU acceleration
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hugoniostat: Hugoniostat shock dynamics
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indent: spherical indenter into a 2d solid
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kim: use of potentials in Knowledge Base for Interatomic Models (KIM)
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line: line segment particles in 2d rigid bodies
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meam: MEAM test for SiC and shear (same as shear examples)
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melt: rapid melt of 3d LJ system
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micelle: self-assembly of small lipid-like molecules into 2d bilayers
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min: energy minimization of 2d LJ melt
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msst: MSST shock dynamics
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neb: nudged elastic band (NEB) calculation for barrier finding
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nemd: non-equilibrium MD of 2d sheared system
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obstacle: flow around two voids in a 2d channel
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peptide: dynamics of a small solvated peptide chain (5-mer)
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peri: Peridynamic model of cylinder impacted by indenter
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pour: pouring of granular particles into a 3d box, then chute flow
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prd: parallel replica dynamics of vacancy diffusion in bulk Si
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reax: RDX and TATB models using the ReaxFF
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rigid: rigid bodies modeled as independent or coupled
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shear: sideways shear applied to 2d solid, with and without a void
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srd: stochastic rotation dynamics (SRD) particles as solvent
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tad: temperature-accelerated dynamics of vacancy diffusion in bulk Si
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tri: triangular particles in rigid bodies :tb(s=:)
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Here is how you might run and visualize one of the sample problems:
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cd indent
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cp ../../src/lmp_linux . # copy LAMMPS executable to this dir
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lmp_linux < in.indent # run the problem :pre
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Running the simulation produces the files {dump.indent} and
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{log.lammps}. You can visualize the dump file as follows:
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../../tools/xmovie/xmovie -scale dump.indent :pre
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If you uncomment the "dump image"_dump_image.html line(s) in the input
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script a series of JPG images will be produced by the run. These can
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be viewed individually or turned into a movie or animated by tools
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like ImageMagick or QuickTime or various Windows-based tools. See the
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"dump image"_dump_image.html doc page for more details. E.g. this
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Imagemagick command would create a GIF file suitable for viewing in a
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browser.
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% convert -loop 1 *.jpg foo.gif :pre
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:line
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There is also a COUPLE directory with examples of how to use LAMMPS as
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a library, either by itself or in tandem with another code or library.
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See the COUPLE/README file to get started.
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There is also an ELASTIC directory with an example script for
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computing elastic constants, using a zero temperature Si example. See
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the in.elastic file for more info.
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There is also a USER directory which contains subdirectories of
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user-provided examples for user packages. See the README files in
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those directories for more info. See the
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"Section_start.html"_Section_start.html file for more info about user
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packages.
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