Trapezoid.C
Go to the documentation of this file.
1 /*---------------------------------------------------------------------------*\
2  ========= |
3  \\ / F ield | OpenFOAM: The Open Source CFD Toolbox
4  \\ / O peration | Website: https://openfoam.org
5  \\ / A nd | Copyright (C) 2013-2021 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 "Trapezoid.H"
28 
29 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
30 
31 namespace Foam
32 {
35 }
36 
37 
38 // * * * * * * * * * * * * * * * * Constructors * * * * * * * * * * * * * * //
39 
41 :
42  ODESolver(ode, dict),
44  err_(n_)
45 {}
46 
47 
48 // * * * * * * * * * * * * * * * Member Functions * * * * * * * * * * * * * //
49 
51 {
52  if (ODESolver::resize())
53  {
55 
56  resizeField(err_);
57 
58  return true;
59  }
60  else
61  {
62  return false;
63  }
64 }
65 
66 
68 (
69  const scalar x0,
70  const scalarField& y0,
71  const label li,
72  const scalarField& dydx0,
73  const scalar dx,
74  scalarField& y
75 ) const
76 {
77  // Predict the state using 1st-order Trapezoid method
78  forAll(y, i)
79  {
80  y[i] = y0[i] + dx*dydx0[i];
81  }
82 
83  // Evaluate the system for the predicted state
84  odes_.derivatives(x0 + dx, y, li, err_);
85 
86  // Update the state as the average between the prediction and the correction
87  // and estimate the error from the difference
88  forAll(y, i)
89  {
90  y[i] = y0[i] + 0.5*dx*(dydx0[i] + err_[i]);
91  err_[i] = 0.5*dx*(err_[i] - dydx0[i]);
92  }
93 
94  return normaliseError(y0, y, err_);
95 }
96 
97 
99 (
100  scalar& x,
101  scalarField& y,
102  const label li,
103  scalar& dxTry
104 ) const
105 {
106  adaptiveSolver::solve(odes_, x, y, li, dxTry);
107 }
108 
109 
110 // ************************************************************************* //
scalar y
#define forAll(list, i)
Loop across all elements in list.
Definition: UList.H:434
Macros for easy insertion into run-time selection tables.
Abstract base-class for ODE system solvers.
Definition: ODESolver.H:51
virtual bool resize()=0
Resize the ODE solver.
Definition: ODESolver.C:89
Abstract base class for the systems of ordinary differential equations.
Definition: ODESystem.H:47
Trapezoidal ODE solver of order (1)2.
Definition: Trapezoid.H:53
virtual bool resize()
Resize the ODE solver.
Definition: Trapezoid.C:50
virtual void solve(scalar &x, scalarField &y, const label li, scalar &dxTry) const
Inherit solve from ODESolver.
Definition: ODESolver.C:116
Trapezoid(const ODESystem &ode, const dictionary &dict)
Construct from ODESystem.
Definition: Trapezoid.C:40
virtual scalar solve(const scalar x0, const scalarField &y0, const label li, const scalarField &dydx0, const scalar dx, scalarField &y) const =0
Solve a single step dx and return the error.
bool resize(const label n)
Resize the ODE solver.
A list of keyword definitions, which are a keyword followed by any number of values (e....
Definition: dictionary.H:162
An ODE solver for chemistry.
Definition: ode.H:53
Namespace for OpenFOAM.
intWM_LABEL_SIZE_t label
A label is an int32_t or int64_t as specified by the pre-processor macro WM_LABEL_SIZE.
Definition: label.H:59
addToRunTimeSelectionTable(polyPatch, mergedCyclicPolyPatch, word)
dimensionedScalar y0(const dimensionedScalar &ds)
defineTypeNameAndDebug(combustionModel, 0)
dictionary dict