git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@1 f3b2605a-c512-4ea7-a41b-209d697bcdaa
This commit is contained in:
71
doc/Section_example.html
Normal file
71
doc/Section_example.html
Normal file
@ -0,0 +1,71 @@
|
||||
<HTML>
|
||||
<CENTER><A HREF = "Section_howto.html">Previous Section</A> - <A HREF = "http://lammps.sandia.gov">LAMMPS WWW Site</A> - <A HREF = "Manual.html">LAMMPS Documentation</A> - <A HREF = "Section_commands.html#comm">LAMMPS Commands</A> - <A HREF = "Section_perf.html">Next Section</A>
|
||||
</CENTER>
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
<HR>
|
||||
|
||||
<H3>5. Example problems
|
||||
</H3>
|
||||
<P>The LAMMPS distribution includes an examples sub-directory with
|
||||
several sample problems. Each problem is in a sub-directory of its
|
||||
own. Most are 2d models so that they run quickly, requiring at most a
|
||||
couple of minutes to run on a desktop machine. Each problem has an
|
||||
input script (in.*) and produces a log file (log.*) and dump file
|
||||
(dump.*) when it runs. Some use a data file (data.*) of initial
|
||||
coordinates as additional input. A few sample log file outputs on
|
||||
different machines and different numbers of processors are included in
|
||||
the directories to compare your answers to. E.g. a log file like
|
||||
log.crack.foo.P means it ran on P processors of machine "foo".
|
||||
</P>
|
||||
<P>The dump files produced by the example runs can be animated using the
|
||||
xmovie tool described in the <A HREF = "Section_tools.html">Tools section</A>. MPEG
|
||||
versions of most of the xmovie animations are also viewable from the
|
||||
Examples page of the <A HREF = "http://lammps.sandia.gov">LAMMPS WWW Site</A>.
|
||||
</P>
|
||||
<P>These are the sample problems in the examples sub-directories:
|
||||
</P>
|
||||
<DIV ALIGN=center><TABLE WIDTH="0%" BORDER=1 >
|
||||
<TR><TD >crack</TD><TD > crack propagation in a 2d solid</TD></TR>
|
||||
<TR><TD >flow</TD><TD > Couette and Poisseuille flow in a 2d channel</TD></TR>
|
||||
<TR><TD >friction</TD><TD > frictional contact of spherical asperities between 2d surfaces</TD></TR>
|
||||
<TR><TD >indent</TD><TD > spherical indenter into a 2d solid</TD></TR>
|
||||
<TR><TD >melt</TD><TD > rapid melt of 3d LJ system</TD></TR>
|
||||
<TR><TD >micelle</TD><TD > self-assembly of small lipid-like molecules into 2d bilayers</TD></TR>
|
||||
<TR><TD >min</TD><TD > energy minimization of 2d LJ melt</TD></TR>
|
||||
<TR><TD >obstacle</TD><TD > flow around two voids in a 2d channel</TD></TR>
|
||||
<TR><TD >peptide</TD><TD > dynamics of a small solvated peptide chain (5-mer)</TD></TR>
|
||||
<TR><TD >pour</TD><TD > pouring of granular particles into a 3d box, then chute flow</TD></TR>
|
||||
<TR><TD >rigid</TD><TD > rigid bodies modeled as independent or coupled</TD></TR>
|
||||
<TR><TD >shear</TD><TD > sideways shear applied to 2d solid, with and without a void
|
||||
</TD></TR></TABLE></DIV>
|
||||
|
||||
<P>Here is how you might run and visualize one of the sample problems:
|
||||
</P>
|
||||
<PRE>cd indent
|
||||
cp ../../src/lmp_linux . # copy LAMMPS executable to this dir
|
||||
lmp_linux < in.indent # run the problem
|
||||
</PRE>
|
||||
<P>Running the simulation produces the files <I>dump.indent</I> and
|
||||
<I>log.lammps</I>. You can visualize the dump file as follows:
|
||||
</P>
|
||||
<PRE>../../tools/xmovie/xmovie -scale dump.indent
|
||||
</PRE>
|
||||
<P>There is also a directory "couple" in the examples sub-directory,
|
||||
which contains a stand-alone code umbrella.cpp that links LAMMPS as a
|
||||
library. The README describes how to build the code. The code itself
|
||||
runs LAMMPS on a subset of processors, sets up a LAMMPS problem
|
||||
by invoking LAMMPS input script commands one at a time, does
|
||||
a run, grabs atom coordinates, changes one atom position, puts
|
||||
them back into LAMMPS, and does another run.
|
||||
</P>
|
||||
<P>This illustrates how an umbrella code could include new models and
|
||||
physics while using LAMMPS to perform MD, or how the umbrella code
|
||||
could call both LAMMPS and some other code to perform a coupled
|
||||
calculation.
|
||||
</P>
|
||||
</HTML>
|
||||
Reference in New Issue
Block a user