| /*---------------------------------------------------------------------------*\ | |
| ========= | | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | |
| \\ / O peration | Website: https://openfoam.org | |
| \\ / A nd | Copyright (C) 2011-2024 OpenFOAM Foundation | |
| \\/ M anipulation | | |
| ------------------------------------------------------------------------------- | |
| License | |
| This file is part of OpenFOAM. | |
| OpenFOAM is free software: you can redistribute it and/or modify it | |
| under the terms of the GNU General Public License as published by | |
| the Free Software Foundation, either version 3 of the License, or | |
| (at your option) any later version. | |
| OpenFOAM is distributed in the hope that it will be useful, but WITHOUT | |
| ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| for more details. | |
| You should have received a copy of the GNU General Public License | |
| along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>. | |
| \*---------------------------------------------------------------------------*/ | |
| // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // | |
| namespace Foam | |
| { | |
| // * * * * * * * * * * * * * Private Member Functions * * * * * * * * * * * // | |
| complexVector OUprocess::WeinerProcess(const scalar deltaT) const | |
| { | |
| return sqrt(deltaT)*complexVector | |
| ( | |
| complex(stdNormal_.sample(), stdNormal_.sample()), | |
| complex(stdNormal_.sample(), stdNormal_.sample()), | |
| complex(stdNormal_.sample(), stdNormal_.sample()) | |
| ); | |
| } | |
| // * * * * * * * * * * * * * * * * Constructors * * * * * * * * * * * * * * // | |
| OUprocess::OUprocess | |
| ( | |
| const Kmesh& kmesh, | |
| const scalar deltaT, | |
| const dictionary& OUdict | |
| ) | |
| : | |
| stdNormal_(0), | |
| Kmesh_(kmesh), | |
| OUfield_(Kmesh_.size()), | |
| alpha_(OUdict.lookup<scalar>("alpha")), | |
| sigma_(OUdict.lookup<scalar>("sigma")), | |
| kUpper_(OUdict.lookup<scalar>("kUpper")), | |
| kLower_(OUdict.lookup<scalar>("kLower")), | |
| scale_((kUpper_ - kLower_)*pow(scalar(Kmesh_.size()), 1.0/vector::dim)) | |
| { | |
| const vectorField& K = Kmesh_; | |
| scalar sqrkUpper_ = sqr(kUpper_); | |
| scalar sqrkLower_ = sqr(kLower_) + small; | |
| scalar sqrK; | |
| forAll(OUfield_, i) | |
| { | |
| if ((sqrK = magSqr(K[i])) < sqrkUpper_ && sqrK > sqrkLower_) | |
| { | |
| OUfield_[i] = scale_*sigma_*WeinerProcess(deltaT); | |
| } | |
| else | |
| { | |
| OUfield_[i] = complexVector | |
| ( | |
| complex(0, 0), | |
| complex(0, 0), | |
| complex(0, 0) | |
| ); | |
| } | |
| } | |
| } | |
| // * * * * * * * * * * * * * * * Member Functions * * * * * * * * * * * * * // | |
| const complexVectorField& OUprocess::newField(const scalar deltaT) const | |
| { | |
| const vectorField& K = Kmesh_; | |
| scalar sqrkUpper_ = sqr(kUpper_); | |
| scalar sqrkLower_ = sqr(kLower_) + small; | |
| scalar sqrK; | |
| forAll(OUfield_, i) | |
| { | |
| if ((sqrK = magSqr(K[i])) < sqrkUpper_ && sqrK > sqrkLower_) | |
| { | |
| OUfield_[i] = | |
| (1.0 - alpha_*deltaT)*OUfield_[i] | |
| + scale_*sigma_*WeinerProcess(deltaT); | |
| } | |
| } | |
| return OUfield_; | |
| } | |
| // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // | |
| } // End namespace Foam | |
| // ************************************************************************* // | |