forked from lijiext/lammps
288 lines
11 KiB
HTML
288 lines
11 KiB
HTML
|
|
|
|
<!DOCTYPE html>
|
|
<!--[if IE 8]><html class="no-js lt-ie9" lang="en" > <![endif]-->
|
|
<!--[if gt IE 8]><!--> <html class="no-js" lang="en" > <!--<![endif]-->
|
|
<head>
|
|
<meta charset="utf-8">
|
|
|
|
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
|
|
|
<title>fix eos/table command — LAMMPS documentation</title>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
|
|
|
|
|
|
|
|
<link rel="stylesheet" href="_static/sphinxcontrib-images/LightBox2/lightbox2/css/lightbox.css" type="text/css" />
|
|
|
|
|
|
|
|
<link rel="top" title="LAMMPS documentation" href="index.html"/>
|
|
|
|
|
|
<script src="_static/js/modernizr.min.js"></script>
|
|
|
|
</head>
|
|
|
|
<body class="wy-body-for-nav" role="document">
|
|
|
|
<div class="wy-grid-for-nav">
|
|
|
|
|
|
<nav data-toggle="wy-nav-shift" class="wy-nav-side">
|
|
<div class="wy-side-nav-search">
|
|
|
|
|
|
|
|
<a href="Manual.html" class="icon icon-home"> LAMMPS
|
|
|
|
|
|
|
|
</a>
|
|
|
|
|
|
<div role="search">
|
|
<form id="rtd-search-form" class="wy-form" action="search.html" method="get">
|
|
<input type="text" name="q" placeholder="Search docs" />
|
|
<input type="hidden" name="check_keywords" value="yes" />
|
|
<input type="hidden" name="area" value="default" />
|
|
</form>
|
|
</div>
|
|
|
|
|
|
</div>
|
|
|
|
<div class="wy-menu wy-menu-vertical" data-spy="affix" role="navigation" aria-label="main navigation">
|
|
|
|
|
|
|
|
<ul>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_intro.html">1. Introduction</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_start.html">2. Getting Started</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_commands.html">3. Commands</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_packages.html">4. Packages</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_accelerate.html">5. Accelerating LAMMPS performance</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_howto.html">6. How-to discussions</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_example.html">7. Example problems</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_perf.html">8. Performance & scalability</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_tools.html">9. Additional tools</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_modify.html">10. Modifying & extending LAMMPS</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_python.html">11. Python interface to LAMMPS</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_errors.html">12. Errors</a></li>
|
|
<li class="toctree-l1"><a class="reference internal" href="Section_history.html">13. Future and history</a></li>
|
|
</ul>
|
|
|
|
|
|
|
|
</div>
|
|
|
|
</nav>
|
|
|
|
<section data-toggle="wy-nav-shift" class="wy-nav-content-wrap">
|
|
|
|
|
|
<nav class="wy-nav-top" role="navigation" aria-label="top navigation">
|
|
<i data-toggle="wy-nav-top" class="fa fa-bars"></i>
|
|
<a href="Manual.html">LAMMPS</a>
|
|
</nav>
|
|
|
|
|
|
|
|
<div class="wy-nav-content">
|
|
<div class="rst-content">
|
|
<div role="navigation" aria-label="breadcrumbs navigation">
|
|
<ul class="wy-breadcrumbs">
|
|
<li><a href="Manual.html">Docs</a> »</li>
|
|
|
|
<li>fix eos/table command</li>
|
|
<li class="wy-breadcrumbs-aside">
|
|
|
|
|
|
<a href="http://lammps.sandia.gov">Website</a>
|
|
<a href="Section_commands.html#comm">Commands</a>
|
|
|
|
</li>
|
|
</ul>
|
|
<hr/>
|
|
|
|
</div>
|
|
<div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article">
|
|
<div itemprop="articleBody">
|
|
|
|
<div class="section" id="fix-eos-table-command">
|
|
<span id="index-0"></span><h1>fix eos/table command<a class="headerlink" href="#fix-eos-table-command" title="Permalink to this headline">¶</a></h1>
|
|
<div class="section" id="syntax">
|
|
<h2>Syntax<a class="headerlink" href="#syntax" title="Permalink to this headline">¶</a></h2>
|
|
<div class="highlight-python"><div class="highlight"><pre>fix ID group-ID eos/table style file N keyword
|
|
</pre></div>
|
|
</div>
|
|
<ul class="simple">
|
|
<li>ID, group-ID are documented in <a class="reference internal" href="fix.html"><em>fix</em></a> command</li>
|
|
<li>eos/table = style name of this fix command</li>
|
|
<li>style = <em>linear</em> = method of interpolation</li>
|
|
<li>file = filename containing the tabulated equation of state</li>
|
|
<li>N = use N values in <em>linear</em> tables</li>
|
|
<li>keyword = name of table keyword correponding to table file</li>
|
|
</ul>
|
|
</div>
|
|
<div class="section" id="examples">
|
|
<h2>Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h2>
|
|
<div class="highlight-python"><div class="highlight"><pre>fix 1 all eos/table linear eos.table 100000 KEYWORD
|
|
</pre></div>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="description">
|
|
<h2>Description<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
|
|
<p>Fix <em>eos/table</em> applies a tabulated mesoparticle equation of state to
|
|
relate the particle internal energy (u_i) to the particle internal
|
|
temperature (dpdTheta_i).</p>
|
|
<p>Fix <em>eos/table</em> creates interpolation tables of length <em>N</em> from
|
|
internal energy values listed in a file as a function of internal
|
|
temperature.</p>
|
|
<p>The interpolation tables are created by fitting cubic splines to the
|
|
file values and interpolating energy values at each of <em>N</em> internal
|
|
temperatures, and vice-versa. During a simulation, these tables are
|
|
used to interpolate internal energy or temperature values as needed.
|
|
The interpolation is done with the <em>linear</em> style.</p>
|
|
<p>For the <em>linear</em> style, the internal temperature is used to find 2
|
|
surrounding table values from which an internal energy is computed by
|
|
linear interpolation, and vice-versa.</p>
|
|
<p>The filename specifies a file containing tabulated internal
|
|
temperature and internal energy values. The keyword specifies a
|
|
section of the file. The format of this file is described below.</p>
|
|
<hr class="docutils" />
|
|
<p>The format of a tabulated file is as follows (without the
|
|
parenthesized comments):</p>
|
|
<div class="highlight-python"><div class="highlight"><pre><span class="c"># EOS TABLE (one or more comment or blank lines)</span>
|
|
</pre></div>
|
|
</div>
|
|
<div class="highlight-python"><div class="highlight"><pre>KEYWORD (keyword is first text on line)
|
|
N 500 (N parameter)
|
|
(blank)
|
|
1 1.00 0.000 (index, internal temperature, internal energy)
|
|
2 1.02 0.001
|
|
...
|
|
500 10.0 0.500
|
|
</pre></div>
|
|
</div>
|
|
<p>A section begins with a non-blank line whose 1st character is not a
|
|
“#”; blank lines or lines starting with “#” can be used as comments
|
|
between sections. The first line begins with a keyword which
|
|
identifies the section. The line can contain additional text, but the
|
|
initial text must match the argument specified in the fix command.</p>
|
|
<p>The next line lists the number of table entries. The parameter “N” is
|
|
required and its value is the number of table entries that follow.
|
|
Note that this may be different than the <em>N</em> specified in the <code class="xref doc docutils literal"><span class="pre">fix</span> <span class="pre">eos/table</span></code> command. Let Ntable = <em>N</em> in the fix
|
|
command, and Nfile = “N” in the tabulated file. What LAMMPS does is a
|
|
preliminary interpolation by creating splines using the Nfile
|
|
tabulated values as nodal points. It uses these to interpolate as
|
|
needed to generate energy and temperature values at Ntable different
|
|
points. The resulting tables of length Ntable are then used as
|
|
described above, when computing energy and temperature relationships.
|
|
This means that if you want the interpolation tables of length Ntable
|
|
to match exactly what is in the tabulated file (with effectively no
|
|
preliminary interpolation), you should set Ntable = Nfile.</p>
|
|
<p>Following a blank line, the next N lines list the tabulated values.
|
|
On each line, the 1st value is the index from 1 to N, the 2nd value is
|
|
the internal temperature (in temperature units), the 3rd value is the
|
|
internal energy (in energy units).</p>
|
|
<p>Note that the internal temperature and internal energy values must
|
|
increase from one line to the next.</p>
|
|
<p>Note that one file can contain many sections, each with a tabulated
|
|
potential. LAMMPS reads the file section by section until it finds
|
|
one that matches the specified keyword.</p>
|
|
</div>
|
|
<hr class="docutils" />
|
|
<div class="section" id="restrictions">
|
|
<h2>Restrictions<a class="headerlink" href="#restrictions" title="Permalink to this headline">¶</a></h2>
|
|
<p>The fix <em>eos/table</em> is only available if LAMMPS is built with the
|
|
USER-DPD package.</p>
|
|
<p>The equation of state must be a monotonically increasing function.</p>
|
|
<p>An exit error will occur if the internal temperature or internal
|
|
energies are not within the table cutoffs.</p>
|
|
</div>
|
|
<div class="section" id="related-commands">
|
|
<h2>Related commands<a class="headerlink" href="#related-commands" title="Permalink to this headline">¶</a></h2>
|
|
<p><a class="reference internal" href="fix_shardlow.html"><em>fix shardlow</em></a>, <code class="xref doc docutils literal"><span class="pre">pair</span> <span class="pre">dpd/fdt</span></code></p>
|
|
<p><strong>Default:</strong> none</p>
|
|
</div>
|
|
</div>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
<footer>
|
|
|
|
|
|
<hr/>
|
|
|
|
<div role="contentinfo">
|
|
<p>
|
|
© Copyright 2013 Sandia Corporation.
|
|
</p>
|
|
</div>
|
|
Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/snide/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>.
|
|
|
|
</footer>
|
|
|
|
</div>
|
|
</div>
|
|
|
|
</section>
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
<script type="text/javascript">
|
|
var DOCUMENTATION_OPTIONS = {
|
|
URL_ROOT:'./',
|
|
VERSION:'',
|
|
COLLAPSE_INDEX:false,
|
|
FILE_SUFFIX:'.html',
|
|
HAS_SOURCE: true
|
|
};
|
|
</script>
|
|
<script type="text/javascript" src="_static/jquery.js"></script>
|
|
<script type="text/javascript" src="_static/underscore.js"></script>
|
|
<script type="text/javascript" src="_static/doctools.js"></script>
|
|
<script type="text/javascript" src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
|
|
<script type="text/javascript" src="_static/sphinxcontrib-images/LightBox2/lightbox2/js/jquery-1.11.0.min.js"></script>
|
|
<script type="text/javascript" src="_static/sphinxcontrib-images/LightBox2/lightbox2/js/lightbox.min.js"></script>
|
|
<script type="text/javascript" src="_static/sphinxcontrib-images/LightBox2/lightbox2-customize/jquery-noconflict.js"></script>
|
|
|
|
|
|
|
|
|
|
|
|
<script type="text/javascript" src="_static/js/theme.js"></script>
|
|
|
|
|
|
|
|
|
|
<script type="text/javascript">
|
|
jQuery(function () {
|
|
SphinxRtdTheme.StickyNav.enable();
|
|
});
|
|
</script>
|
|
|
|
|
|
</body>
|
|
</html> |