1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
|
/* Lattice Boltzmann sample, written in C++, using the OpenLB
* library
*
* Copyright (C) 2006-2015 Fabian Klemens, Jonas Latt, Mathias J. Krause
* Vojtech Cvrcek, Peter Weisbrod
* E-mail contact: info@openlb.net
* The most recent release of OpenLB can be downloaded at
* <http://www.openlb.net/>
*
* This program 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 2
* of the License, or (at your option) any later version.
*
* This program 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 this program; if not, write to the Free
* Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/* settlingCube3d.cpp:
* The case examines the settling of a cubical silica particle
* under the influence of gravity.
* The object is surrounded by water in a rectangular domain
* limited by no-slip boundary conditions.
* For the calculation of forces an DNS approach is chosen
* which also leads to a back-coupling of the particle on the fluid,
* inducing a flow.
*
* The simulation is based on the homogenised lattice Boltzmann approach
* (HLBM) introduced in "Particle flow simulations with homogenised
* lattice Boltzmann methods" by Krause et al.
* and extended in "Towards the simulation of arbitrarily shaped 3D particles
* using a homogenised lattice Boltzmann method" by Trunk et al.
* for the simulation of 3D particles.
*
* This example demonstrates the usage of HLBM in the OpenLB framework.
*/
#include "olb3D.h"
#include "olb3D.hh" // use generic version only!
#include <vector>
#include <cmath>
#include <iostream>
#include <fstream>
using namespace olb;
using namespace olb::descriptors;
using namespace olb::graphics;
using namespace olb::util;
using namespace std;
typedef double T;
#define DESCRIPTOR D3Q19<POROSITY,VELOCITY_NUMERATOR,VELOCITY_DENOMINATOR>
#define WriteVTK
// Discretization Settings
int res = 30;
T const charLatticeVelocity = 0.01;
// Time Settings
T const maxPhysT = 0.5; // max. simulation time in s
T const iTwrite = 0.02; // write out intervall in s
// Domain Settings
T const lengthX = 0.01;
T const lengthY = 0.01;
T const lengthZ = 0.05;
// Fluid Settings
T const physDensity = 1000;
T const physViscosity = 1E-5;
//Particle Settings
T centerX = lengthX*.5;
T centerY = lengthY*.5;
T centerZ = lengthZ*.9;
T const cubeDensity = 2500;
T const cubeEdgeLength = 0.0025;
Vector<T,3> cubeCenter = {centerX,centerY,centerZ};
Vector<T,3> cubeOrientation = {0.,15.,0.};
Vector<T,3> cubeVelocity = {0.,0.,0.};
Vector<T,3> externalAcceleration = {.0, .0, -9.81 * (1. - physDensity / cubeDensity)};
// Characteristic Quantities
T const charPhysLength = lengthX;
T const charPhysVelocity = 0.15; // Assumed maximal velocity
// Prepare geometry
void prepareGeometry(UnitConverter<T,DESCRIPTOR> const& converter,
SuperGeometry3D<T>& superGeometry)
{
OstreamManager clout(std::cout, "prepareGeometry");
clout << "Prepare Geometry ..." << std::endl;
superGeometry.rename(0, 2);
superGeometry.rename(2, 1, 1, 1, 1);
superGeometry.clean();
superGeometry.innerClean();
superGeometry.checkForErrors();
superGeometry.getStatistics().print();
clout << "Prepare Geometry ... OK" << std::endl;
return;
}
// Set up the geometry of the simulation
void prepareLattice(
SuperLattice3D<T, DESCRIPTOR>& sLattice, UnitConverter<T,DESCRIPTOR> const& converter,
Dynamics<T, DESCRIPTOR>& designDynamics,
sOnLatticeBoundaryCondition3D<T, DESCRIPTOR>& sBoundaryCondition,
SuperGeometry3D<T>& superGeometry)
{
OstreamManager clout(std::cout, "prepareLattice");
clout << "Prepare Lattice ..." << std::endl;
clout << "setting Velocity Boundaries ..." << std::endl;
/// Material=0 -->do nothing
sLattice.defineDynamics(superGeometry, 0, &instances::getNoDynamics<T, DESCRIPTOR>());
sLattice.defineDynamics(superGeometry, 1, &designDynamics);
sLattice.defineDynamics(superGeometry, 2, &instances::getBounceBack<T, DESCRIPTOR>());
clout << "Prepare Lattice ... OK" << std::endl;
}
//Set Boundary Values
void setBoundaryValues(SuperLattice3D<T, DESCRIPTOR>& sLattice,
UnitConverter<T,DESCRIPTOR> const& converter, int iT,
SuperGeometry3D<T>& superGeometry)
{
OstreamManager clout(std::cout, "setBoundaryValues");
if (iT == 0) {
AnalyticalConst3D<T, T> zero(0.);
AnalyticalConst3D<T, T> one(1.);
sLattice.defineField<descriptors::POROSITY>(superGeometry.getMaterialIndicator({0,1,2}), one);
// Set initial condition
AnalyticalConst3D<T, T> ux(0.);
AnalyticalConst3D<T, T> uy(0.);
AnalyticalConst3D<T, T> uz(0.);
AnalyticalConst3D<T, T> rho(1.);
AnalyticalComposed3D<T, T> u(ux, uy, uz);
//Initialize all values of distribution functions to their local equilibrium
sLattice.defineRhoU(superGeometry, 1, rho, u);
sLattice.iniEquilibrium(superGeometry, 1, rho, u);
// Make the lattice ready for simulation
sLattice.initialize();
}
}
/// Computes the pressure drop between the voxels before and after the cylinder
void getResults(SuperLattice3D<T, DESCRIPTOR>& sLattice,
UnitConverter<T,DESCRIPTOR> const& converter, int iT,
SuperGeometry3D<T>& superGeometry, Timer<double>& timer,
ParticleDynamics3D<T, DESCRIPTOR> particleDynamics)
{
OstreamManager clout(std::cout, "getResults");
#ifdef WriteVTK
SuperVTMwriter3D<T> vtkWriter("sedimentation");
SuperLatticePhysVelocity3D<T, DESCRIPTOR> velocity(sLattice, converter);
SuperLatticePhysPressure3D<T, DESCRIPTOR> pressure(sLattice, converter);
SuperLatticePhysExternalPorosity3D<T, DESCRIPTOR> externalPor(sLattice, converter);
vtkWriter.addFunctor(velocity);
vtkWriter.addFunctor(pressure);
vtkWriter.addFunctor(externalPor);
if (iT == 0) {
/// Writes the converter log file
SuperLatticeGeometry3D<T, DESCRIPTOR> geometry(sLattice, superGeometry);
SuperLatticeCuboid3D<T, DESCRIPTOR> cuboid(sLattice);
SuperLatticeRank3D<T, DESCRIPTOR> rank(sLattice);
vtkWriter.write(geometry);
vtkWriter.write(cuboid);
vtkWriter.write(rank);
vtkWriter.createMasterFile();
}
if (iT % converter.getLatticeTime(iTwrite) == 0) {
vtkWriter.write(iT);
}
#endif
/// Writes output on the console
if (iT % converter.getLatticeTime(iTwrite) == 0) {
timer.update(iT);
timer.printStep();
sLattice.getStatistics().print(iT, converter.getPhysTime(iT));
particleDynamics.print();
}
}
int main(int argc, char* argv[])
{
/// === 1st Step: Initialization ===
olbInit(&argc, &argv);
singleton::directories().setOutputDir("./tmp/");
OstreamManager clout(std::cout, "main");
UnitConverterFromResolutionAndLatticeVelocity<T,DESCRIPTOR> converter(
(int) res, //resolution
( T ) charLatticeVelocity, //charLatticeVelocity
( T ) charPhysLength, //charPhysLength
( T ) charPhysVelocity, //charPhysVelocity
( T ) physViscosity, //physViscosity
( T ) physDensity //physDensity
);
converter.print();
/// === 2rd Step: Prepare Geometry ===
/// Instantiation of a cuboidGeometry with weights
std::vector<T> extend(3, T());
extend[0] = lengthX;
extend[1] = lengthY;
extend[2] = lengthZ;
std::vector<T> origin(3, T());
IndicatorCuboid3D<T> cuboid(extend, origin);
#ifdef PARALLEL_MODE_MPI
CuboidGeometry3D<T> cuboidGeometry(cuboid, converter.getConversionFactorLength(), singleton::mpi().getSize());
#else
CuboidGeometry3D<T> cuboidGeometry(cuboid, converter.getConversionFactorLength(), 7);
#endif
cuboidGeometry.print();
HeuristicLoadBalancer<T> loadBalancer(cuboidGeometry);
SuperGeometry3D<T> superGeometry(cuboidGeometry, loadBalancer, 2);
prepareGeometry(converter, superGeometry);
/// === 3rd Step: Prepare Lattice ===
SuperLattice3D<T, DESCRIPTOR> sLattice(superGeometry);
PorousParticleBGKdynamics<T, DESCRIPTOR, false> designDynamics(converter.getLatticeRelaxationFrequency(), instances::getBulkMomenta<T, DESCRIPTOR>());
sOnLatticeBoundaryCondition3D<T, DESCRIPTOR> sBoundaryCondition(sLattice);
createLocalBoundaryCondition3D<T, DESCRIPTOR>(sBoundaryCondition);
prepareLattice(sLattice, converter, designDynamics, sBoundaryCondition, superGeometry);
/// === 4th Step: Main Loop with Timer ===
Timer<double> timer(converter.getLatticeTime(maxPhysT), superGeometry.getStatistics().getNvoxel());
timer.start();
// Create Particle Dynamics
ParticleDynamics3D<T, DESCRIPTOR> particleDynamics(sLattice
|