lennardJones.C
Go to the documentation of this file.
1 /*---------------------------------------------------------------------------*\
2  ========= |
3  \\ / F ield | OpenFOAM: The Open Source CFD Toolbox
4  \\ / O peration |
5  \\ / A nd | Copyright (C) 2011 OpenFOAM Foundation
6  \\/ M anipulation |
7 -------------------------------------------------------------------------------
8 License
9  This file is part of OpenFOAM.
10 
11  OpenFOAM is free software: you can redistribute it and/or modify it
12  under the terms of the GNU General Public License as published by
13  the Free Software Foundation, either version 3 of the License, or
14  (at your option) any later version.
15 
16  OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
17  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
18  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
19  for more details.
20 
21  You should have received a copy of the GNU General Public License
22  along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>.
23 
24 \*---------------------------------------------------------------------------*/
25 
26 #include "lennardJones.H"
28 
29 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
30 
31 namespace Foam
32 {
33 namespace pairPotentials
34 {
35 
36 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
37 
38 defineTypeNameAndDebug(lennardJones, 0);
39 
41 (
42  pairPotential,
43  lennardJones,
44  dictionary
45 );
46 
47 
48 // * * * * * * * * * * * * * * * * Constructors * * * * * * * * * * * * * * //
49 
51 (
52  const word& name,
53  const dictionary& pairPotentialProperties
54 )
55 :
56  pairPotential(name, pairPotentialProperties),
57  lennardJonesCoeffs_(pairPotentialProperties.subDict(typeName + "Coeffs")),
58  sigma_(readScalar(lennardJonesCoeffs_.lookup("sigma"))),
59  epsilon_(readScalar(lennardJonesCoeffs_.lookup("epsilon")))
60 {
61  setLookupTables();
62 }
63 
64 
65 // * * * * * * * * * * * * * * Member Functions * * * * * * * * * * * * * * //
66 
67 scalar lennardJones::unscaledEnergy(const scalar r) const
68 {
69  // (rIJ/sigma)^-2
70  scalar ir2 = (sigma_/r)*(sigma_/r);
71 
72  // (rIJ/sigma)^-6
73  scalar ir6 = ir2*ir2*ir2;
74 
75  return 4.0 * epsilon_*(ir6*(ir6 - 1.0));
76 }
77 
78 
79 bool lennardJones::read(const dictionary& pairPotentialProperties)
80 {
81  pairPotential::read(pairPotentialProperties);
82 
83  lennardJonesCoeffs_ = pairPotentialProperties.subDict(typeName + "Coeffs");
84 
85  lennardJonesCoeffs_.lookup("sigma") >> sigma_;
86  lennardJonesCoeffs_.lookup("epsilon") >> epsilon_;
87 
88  return true;
89 }
90 
91 
92 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
93 
94 } // End namespace pairPotentials
95 } // End namespace Foam
96 
97 // ************************************************************************* //
A list of keyword definitions, which are a keyword followed by any number of values (e...
Definition: dictionary.H:137
virtual bool read(const dictionary &pairPotentialProperties)=0
Read pairPotential dictionary.
Macros for easy insertion into run-time selection tables.
const dictionary & subDict(const word &) const
Find and return a sub-dictionary.
Definition: dictionary.C:692
A class for handling words, derived from string.
Definition: word.H:59
lennardJones(const word &name, const dictionary &pairPotentialProperties)
Construct from components.
Definition: lennardJones.C:51
bool readScalar(const char *buf, doubleScalar &s)
Read whole of buf as a scalar. Return true if succesful.
Definition: doubleScalar.H:63
scalar unscaledEnergy(const scalar r) const
Definition: lennardJones.C:67
defineTypeNameAndDebug(azizChen, 0)
addToRunTimeSelectionTable(pairPotential, azizChen, dictionary)
bool read(const dictionary &pairPotentialProperties)
Read dictionary.
Definition: lennardJones.C:79
Namespace for OpenFOAM.
ITstream & lookup(const word &, bool recursive=false, bool patternMatch=true) const
Find and return an entry data stream.
Definition: dictionary.C:576