filteredLinear2V.H
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1/*---------------------------------------------------------------------------*\
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3 \\ / F ield | OpenFOAM: The Open Source CFD Toolbox
4 \\ / O peration |
5 \\ / A nd | www.openfoam.com
6 \\/ M anipulation |
7-------------------------------------------------------------------------------
8 Copyright (C) 2011-2015 OpenFOAM Foundation
9-------------------------------------------------------------------------------
10License
11 This file is part of OpenFOAM.
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14 under the terms of the GNU General Public License as published by
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21 for more details.
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23 You should have received a copy of the GNU General Public License
24 along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>.
25
26Class
27 Foam::filteredLinear2VLimiter
28
29Description
30 Class to generate weighting factors for the filteredLinear2V
31 differencing scheme.
32
33 The aim is to remove high-frequency modes with "staggering"
34 characteristics from vector fields by comparing the face gradient in
35 the direction of maximum gradient with both neighbouring cell gradients
36 and introduce small amounts of upwind in order to damp these modes.
37
38 Used in conjunction with the template class LimitedScheme.
39
40SourceFiles
41 filteredLinear2V.C
42
43\*---------------------------------------------------------------------------*/
44
45#ifndef filteredLinear2V_H
46#define filteredLinear2V_H
47
48#include "vector.H"
49
50// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
51
52namespace Foam
53{
54
55/*---------------------------------------------------------------------------*\
56 Class filteredLinear2VLimiter Declaration
57\*---------------------------------------------------------------------------*/
58
59template<class LimiterFunc>
61:
62 public LimiterFunc
63{
64 // Private data
65
66 // Scaling coefficient for the gradient ratio,
67 // 0 = linear
68 // 1 = fully limited
69 scalar k_;
70
71 // Maximum allowed overshoot/undershoot relative to the difference
72 // across the face.
73 // On input:
74 // 0 = no overshoot/undershoot
75 // 1 = overshoot/undershoot equal to the difference across the face
76 // Note: After input 1 is added to l_
77 scalar l_;
78
79
80public:
83 :
84 k_(readScalar(is)),
85 l_(readScalar(is))
86 {
87 if (k_ < 0 || k_ > 1)
88 {
90 << "coefficient = " << k_
91 << " should be >= 0 and <= 1"
93 }
94
95 if (l_ < 0 || l_ > 1)
96 {
98 << "coefficient = " << l_
99 << " should be >= 0 and <= 1"
100 << exit(FatalIOError);
101 }
102
103 l_ += 1.0;
104 }
106 scalar limiter
107 (
108 const scalar cdWeight,
109 const scalar faceFlux,
110 const typename LimiterFunc::phiType& phiP,
111 const typename LimiterFunc::phiType& phiN,
112 const typename LimiterFunc::gradPhiType& gradcP,
113 const typename LimiterFunc::gradPhiType& gradcN,
114 const vector& d
115 ) const
116 {
117 // Difference across face
118 vector dfV = phiN - phiP;
119
120 // Scalar difference across the face
121 // in the direction in which the difference is largest
122 scalar df = dfV & dfV;
123
124 // Twice differences across face-neighbour cells
125 // in the direction in which the face-difference is largest
126 scalar tdcP = 2*(dfV & (d & gradcP));
127 scalar tdcN = 2*(dfV & (d & gradcN));
128
129 // Calculate the limiter according to the sign of the face difference
130 scalar limiter;
131
132 if (df > 0)
133 {
134 limiter = l_
135 - k_*min(max(df - tdcP, 0), max(df - tdcN, 0))
136 /(max(mag(df), max(mag(tdcP), mag(tdcN))) + VSMALL);
137 }
138 else
139 {
140 limiter = l_
141 - k_*min(max(tdcP - df, 0), max(tdcN - df, 0))
142 /(max(mag(df), max(mag(tdcP), mag(tdcN))) + VSMALL);
143 }
144
145 // Limit the limiter between linear and upwind
146 return max(min(limiter, 1), 0);
147 }
148};
149
150
151// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
152
153} // End namespace Foam
154
155// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
156
157#endif
158
159// ************************************************************************* //
An Istream is an abstract base class for all input systems (streams, files, token lists etc)....
Definition: Istream.H:64
Class to generate weighting factors for the filteredLinear2V differencing scheme.
scalar limiter(const scalar cdWeight, const scalar faceFlux, const typename LimiterFunc::phiType &phiP, const typename LimiterFunc::phiType &phiN, const typename LimiterFunc::gradPhiType &gradcP, const typename LimiterFunc::gradPhiType &gradcN, const vector &d) const
#define FatalIOErrorInFunction(ios)
Report an error message using Foam::FatalIOError.
Definition: error.H:473
Namespace for OpenFOAM.
label max(const labelHashSet &set, label maxValue=labelMin)
Find the max value in labelHashSet, optionally limited by second argument.
Definition: hashSets.C:47
dimensioned< typename typeOfMag< Type >::type > mag(const dimensioned< Type > &dt)
label min(const labelHashSet &set, label minValue=labelMax)
Find the min value in labelHashSet, optionally limited by second argument.
Definition: hashSets.C:33
IOerror FatalIOError
errorManipArg< error, int > exit(error &err, const int errNo=1)
Definition: errorManip.H:130