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1 | // -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- | ||
2 | // vi: set et ts=4 sw=4 sts=4: | ||
3 | // | ||
4 | // SPDX-FileCopyrightInfo: Copyright © DuMux Project contributors, see AUTHORS.md in root folder | ||
5 | // SPDX-License-Identifier: GPL-3.0-or-later | ||
6 | // | ||
7 | /*! | ||
8 | * \file | ||
9 | * \ingroup EmbeddedCoupling | ||
10 | * \brief Integration over cylindrical and elliptic cylindrical domains | ||
11 | * Lowest order integration formulas that are mostly useful to evenly distribute | ||
12 | * mass in a cylindrical domain. | ||
13 | */ | ||
14 | |||
15 | #ifndef DUMUX_MULTIDOMAIN_EMBEDDED_CYLINDERINTEGRATOR_HH | ||
16 | #define DUMUX_MULTIDOMAIN_EMBEDDED_CYLINDERINTEGRATOR_HH | ||
17 | |||
18 | #include <cmath> | ||
19 | #include <algorithm> | ||
20 | #include <numeric> | ||
21 | #include <iterator> | ||
22 | #include <utility> | ||
23 | #include <tuple> | ||
24 | #include <limits> | ||
25 | |||
26 | #include <dune/common/fvector.hh> | ||
27 | |||
28 | #include <dumux/common/math.hh> | ||
29 | #include <dumux/multidomain/embedded/circlepoints.hh> | ||
30 | |||
31 | namespace Dumux::EmbeddedCoupling { | ||
32 | |||
33 | /*! | ||
34 | * \ingroup EmbeddedCoupling | ||
35 | * \brief Helper class to integrate over a cylinder domain | ||
36 | * \note This is mostly useful if the integral is known and the | ||
37 | * integral mass has to be locally distributed to some non-matching domain | ||
38 | * \note The algorithm creates (almost) evenly spaced area elements on a circle | ||
39 | * and extrudes this pattern into a cylinder. Each sub-cell is an integration | ||
40 | * point with constant ansatz on the sub-cell (lowest order integration formula). | ||
41 | * Hence to improve the quality of the integral, increase the sample size. | ||
42 | * \note The volume integral of a constant function is exact | ||
43 | * See Beckers & Beckers (2012) doi:10.1016/j.comgeo.2012.01.011 for circle distribution | ||
44 | * and T. Koch PhD thesis (2020), Section 7.2.4. | ||
45 | */ | ||
46 | template<class Scalar> | ||
47 | class CylinderIntegration | ||
48 | { | ||
49 | using GlobalPosition = Dune::FieldVector<Scalar, 3>; | ||
50 | |||
51 | public: | ||
52 | /*! | ||
53 | * \brief Constructor | ||
54 | * \param rStep characteristic relative integration length (positive real number between 0 and 1) | ||
55 | * \note half the characteristic length means 2*2*2=8 times more integration points | ||
56 | */ | ||
57 | 1 | CylinderIntegration(const Scalar rStep) | |
58 | 4 | { | |
59 | 1 | rSamples_ = characteristicLengthToNumSamples_(rStep); | |
60 |
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1 | initialize_(); |
61 | 1 | } | |
62 | |||
63 | /*! | ||
64 | * \brief Constructor | ||
65 | * \param rStep characteristic relative integration length in r-direction (positive real number between 0 and 1) | ||
66 | * \param zStep characteristic relative integration length in z-direction (positive real number between 0 and 1) | ||
67 | * \note Use this constructor to achieve a non-balanced (away from 1) aspect ratio between r and z-direction | ||
68 | */ | ||
69 | 6 | CylinderIntegration(const Scalar rStep, const Scalar zStep) | |
70 |
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24 | : zStepFixed_(true) |
71 | { | ||
72 | using std::ceil; using std::clamp; | ||
73 | 6 | rSamples_ = characteristicLengthToNumSamples_(rStep); | |
74 | 6 | zSamples_ = characteristicLengthToNumSamples_(zStep); | |
75 |
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6 | initialize_(); |
76 | 6 | } | |
77 | |||
78 | /*! | ||
79 | * \brief Set the geometry of the cylinder | ||
80 | * \param bottomCenter bottom center position | ||
81 | * \param topCenter top center position | ||
82 | * \param radius cylinder radius | ||
83 | * \param verbosity the verbosity level (default: 0 -> no terminal output) | ||
84 | */ | ||
85 | 1425 | void setGeometry(const GlobalPosition& bottomCenter, | |
86 | const GlobalPosition& topCenter, | ||
87 | const Scalar radius, | ||
88 | int verbosity = 0) | ||
89 | { | ||
90 | 1425 | const auto zAxis = (topCenter-bottomCenter); | |
91 | 1425 | const auto height = zAxis.two_norm(); | |
92 | 1425 | const auto zAxisUnitVector = zAxis/height; | |
93 | |||
94 | // compute step size in r-direction | ||
95 | 1425 | const auto rStep = radius/Scalar(rSamples_); | |
96 | |||
97 | // compute zSamples from r samples if not specified by the user | ||
98 | using std::ceil; | ||
99 |
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1425 | if (!zStepFixed_) |
100 |
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2 | zSamples_ = std::max<std::size_t>(1, ceil(height/rStep)); |
101 | 1425 | const auto zStep = height/Scalar(zSamples_); | |
102 | |||
103 | // compute offsets for index calculation | ||
104 |
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1425 | auto kOffset = numRingSamples_; |
105 |
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5700 | std::partial_sum(kOffset.begin(), kOffset.end(), kOffset.begin()); |
106 | |||
107 | // compute total number of samples | ||
108 | 1425 | numPoints_ = zSamples_*circleSamples_; | |
109 |
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1425 | if (verbosity > 0) |
110 |
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2 | std::cout << "CylinderIntegration -- number of integration points: " << numPoints_ << std::endl; |
111 | |||
112 | // resize integration points and integration elements | ||
113 |
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1425 | integrationElement_.resize(numPoints_); |
114 |
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1425 | points_.resize(numPoints_); |
115 | |||
116 | // reserve enough memory for the points on each ring | ||
117 |
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4275 | std::vector<GlobalPosition> ringPoints; |
118 |
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2850 | ringPoints.reserve(numRingSamples_.back()); |
119 | |||
120 | // compute integration points and integration elements | ||
121 |
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2887 | for (std::size_t i = 0; i < zSamples_; ++i) |
122 | { | ||
123 | // for each cylinder slice i | ||
124 | 1462 | auto sliceCenter = bottomCenter; | |
125 | 1462 | sliceCenter.axpy((Scalar(i)+0.5)*zStep, zAxisUnitVector); | |
126 | |||
127 | // generate circle points for each ring j | ||
128 |
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25012 | for (std::size_t j = 0; j < rSamples_; ++j) |
129 | { | ||
130 | 23550 | const auto r = (Scalar(j)+0.5)*rStep; | |
131 |
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47100 | circlePoints(ringPoints, sincos_[j], sliceCenter, zAxisUnitVector, r); |
132 |
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23550 | const auto ringOffest = j > 0 ? kOffset[j-1] : 0; |
133 | 23550 | const auto ringSamples = numRingSamples_[j]; | |
134 | // volume of each element in ring | ||
135 | // total ring volume is given by M_PI*rStep*rStep*zStep*((j+1)^2 - j^2) | ||
136 | 23550 | const auto integrationElement = M_PI*rStep*rStep*zStep*(1.0 + 2.0*Scalar(j))/ringSamples; | |
137 |
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3461234 | for (std::size_t k = 0; k < ringSamples; ++k) |
138 | { | ||
139 | 3437684 | const std::size_t idx = k + ringOffest + circleSamples_*i; | |
140 | 6875368 | points_[idx] = ringPoints[k]; | |
141 | 6875368 | integrationElement_[idx] = integrationElement; | |
142 | } | ||
143 | } | ||
144 | } | ||
145 | 1425 | } | |
146 | |||
147 | //! The integration element of the ith integration point | ||
148 | Scalar integrationElement(std::size_t i) const | ||
149 |
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24799942 | { return integrationElement_[i]; } |
150 | |||
151 | //! The ith integration point | ||
152 | const GlobalPosition& integrationPoint(std::size_t i) const | ||
153 | 24753418 | { return points_[i]; } | |
154 | |||
155 | //! The number of integration points | ||
156 | ✗ | std::size_t size() const | |
157 | ✗ | { return numPoints_; } | |
158 | |||
159 | private: | ||
160 | 7 | void initialize_() | |
161 | { | ||
162 | // precompute number of cells in ring and total circle samples | ||
163 | 7 | circleSamples_ = 0; | |
164 | 7 | numRingSamples_.resize(rSamples_); | |
165 |
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537 | for (int j = 0; j < rSamples_; ++j) |
166 | { | ||
167 | // number of cells in ring j | ||
168 | using std::floor; | ||
169 | 530 | numRingSamples_[j] = floor(2*M_PI*(Scalar(j)+0.5)); | |
170 | 530 | circleSamples_ += numRingSamples_[j]; | |
171 | } | ||
172 | |||
173 | // optimization because calling too many sin/cos can be really expensive | ||
174 | 7 | sincos_.resize(rSamples_); | |
175 |
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537 | for (int j = 0; j < rSamples_; ++j) |
176 | { | ||
177 | 530 | const auto numPoints = numRingSamples_[j]; | |
178 | 530 | sincos_[j].resize(2*numPoints); | |
179 | 530 | Scalar t = 0 + 0.1; | |
180 |
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158910 | for (std::size_t i = 0; i < numPoints; ++i) |
181 | { | ||
182 | using std::sin; using std::cos; | ||
183 |
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316760 | sincos_[j][2*i] = sin(t); |
184 |
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158380 | sincos_[j][2*i + 1] = cos(t); |
185 | 158380 | t += 2*M_PI/numPoints; | |
186 |
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158380 | if (t > 2*M_PI) t -= 2*M_PI; |
187 | } | ||
188 | } | ||
189 | 7 | } | |
190 | |||
191 | // invert characteristic length (between 0 and 1) | ||
192 | // and make sure there is no integer wrap around for small ratios | ||
193 | ✗ | std::size_t characteristicLengthToNumSamples_(const Scalar cl) const | |
194 | { | ||
195 | using std::clamp; using std::min; using std::max; using std::ceil; using std::nexttoward; | ||
196 | ✗ | const Scalar clampedCl = clamp(cl, std::numeric_limits<Scalar>::min(), 1.0); | |
197 | ✗ | const Scalar floatNumSamples = ceil(1.0/clampedCl); | |
198 | ✗ | const Scalar largestValidFloat = nexttoward(std::numeric_limits<std::size_t>::max(), 0.0); | |
199 | ✗ | return static_cast<std::size_t>(min(floatNumSamples, largestValidFloat)); | |
200 | } | ||
201 | |||
202 | bool zStepFixed_ = false; | ||
203 | std::size_t zSamples_, rSamples_, numPoints_, circleSamples_; | ||
204 | std::vector<Scalar> integrationElement_; | ||
205 | std::vector<GlobalPosition> points_; | ||
206 | std::vector<std::size_t> numRingSamples_; | ||
207 | std::vector<std::vector<Scalar>> sincos_; | ||
208 | }; | ||
209 | |||
210 | namespace Detail { | ||
211 | //! check if a point is in an ellipse | ||
212 | template<class GlobalPosition> | ||
213 | 10880 | inline bool pointInEllipse(const GlobalPosition& p, | |
214 | const GlobalPosition& center, | ||
215 | const GlobalPosition& firstAxis, | ||
216 | const GlobalPosition& secondAxis, | ||
217 | const GlobalPosition& normal, | ||
218 | const typename GlobalPosition::value_type a, | ||
219 | const typename GlobalPosition::value_type b) | ||
220 | { | ||
221 | 10880 | const auto d = p-center; | |
222 | // early return if point is not on the ellipse plane | ||
223 |
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10880 | if (d*normal > 1e-7*a) |
224 | return false; | ||
225 | |||
226 | // check if it's actually within the ellipse | ||
227 | const auto da = (d*firstAxis); | ||
228 | 10880 | const auto db = (d*secondAxis); | |
229 | |||
230 | 10880 | return (da*da/(a*a) + db*db/(b*b) < 1.0); | |
231 | } | ||
232 | |||
233 | //! construct evenly distributed integration points on an ellipse | ||
234 | template<class GlobalPosition> | ||
235 | inline std::pair<std::vector<GlobalPosition>, typename GlobalPosition::value_type> | ||
236 | 6 | ellipseIntegrationPoints(const GlobalPosition& center, | |
237 | const GlobalPosition& firstUnitAxis, | ||
238 | const GlobalPosition& secondUnitAxis, | ||
239 | typename GlobalPosition::value_type a, | ||
240 | typename GlobalPosition::value_type b, | ||
241 | const GlobalPosition& normal, | ||
242 | typename GlobalPosition::value_type characteristicLength) | ||
243 | { | ||
244 | // choose step size in a-direction | ||
245 | 6 | const auto aStep = characteristicLength; | |
246 | |||
247 | using std::floor; | ||
248 |
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6 | const std::size_t aSamples = std::max<std::size_t>(floor(2*a/aStep), 1); |
249 |
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6 | const std::size_t bSamples = std::max<std::size_t>(floor(2*b/aStep), 1); |
250 | 6 | const auto bStep = 2*b / bSamples; | |
251 | |||
252 | // reserve upper limit estimate for memory needed | ||
253 |
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6 | std::vector<GlobalPosition> points; |
254 |
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6 | points.reserve(aSamples*bSamples); |
255 | |||
256 | // walk over lattice grid and reject points outside the ellipse | ||
257 | 6 | auto startAB = center; | |
258 | 6 | startAB.axpy(-a + 0.5*aStep, firstUnitAxis); | |
259 | 6 | startAB.axpy(-b + 0.5*bStep, secondUnitAxis); | |
260 |
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406 | for (std::size_t as = 0; as < aSamples; ++as) |
261 | { | ||
262 | 400 | auto posA = startAB; | |
263 | 400 | posA.axpy(as*aStep, firstUnitAxis); | |
264 |
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11280 | for (std::size_t bs = 0; bs < bSamples; ++bs) |
265 | { | ||
266 | 10880 | auto pos = posA; | |
267 | 10880 | pos.axpy(bs*bStep, secondUnitAxis); | |
268 |
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10880 | if (pointInEllipse(pos, center, firstUnitAxis, secondUnitAxis, normal, a, b)) |
269 |
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8568 | points.emplace_back(std::move(pos)); |
270 | } | ||
271 | } | ||
272 | // return points and integration element | ||
273 |
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12 | return {points, aStep*bStep}; |
274 | } | ||
275 | } // end namespace Detail | ||
276 | |||
277 | /*! | ||
278 | * \ingroup EmbeddedCoupling | ||
279 | * \brief Helper class to integrate over an elliptic cylinder domain | ||
280 | * \note The cylinder caps do not have to be orthogonal to the centerline axis but top and bottom cap are parallel planes | ||
281 | * \note This is mostly useful if the integral is known and the | ||
282 | * integral mass has to be locally distributed to some non-matching domain | ||
283 | * \note The algorithm is based on evenly spaced area elements with rejection sampling. | ||
284 | * To improve the quality of the integral, increase the sample size. | ||
285 | * \note The volume integral of a constant function is exact | ||
286 | * See Koch et al. (2020) https://doi.org/10.1016/j.jcp.2020.109369 | ||
287 | */ | ||
288 | template<class Scalar> | ||
289 |
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6 | class EllipticCylinderIntegration |
290 | { | ||
291 | using GlobalPosition = Dune::FieldVector<Scalar, 3>; | ||
292 | |||
293 | public: | ||
294 | /*! | ||
295 | * \brief Constructor | ||
296 | * \param relCharLength characteristic relative integration length (real number between 0 and 1) | ||
297 | * \note half the characteristic length means 2*2*2=8 times more integration points | ||
298 | */ | ||
299 | 3 | explicit EllipticCylinderIntegration(const Scalar relCharLength) | |
300 |
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6 | : relCharLength_(relCharLength) |
301 | {} | ||
302 | |||
303 | /*! | ||
304 | * \brief Set the geometry of elliptic cylinder | ||
305 | * \param bottomCenter bottom center position | ||
306 | * \param topCenter top center position | ||
307 | * \param firstAxis first ellipse axis (length corresponding to axis length) | ||
308 | * \param secondAxis second ellipse axis (length corresponding to axis length) | ||
309 | * \param verbosity the verbosity level (default: 0 -> no terminal output) | ||
310 | */ | ||
311 | 3 | void setGeometry(const GlobalPosition& bottomCenter, | |
312 | const GlobalPosition& topCenter, | ||
313 | const GlobalPosition& firstAxis, | ||
314 | const GlobalPosition& secondAxis, | ||
315 | int verbosity = 0) | ||
316 | { | ||
317 | 3 | const auto a = firstAxis.two_norm(); | |
318 | 3 | const auto b = secondAxis.two_norm(); | |
319 | 3 | const auto characteristicLength = relCharLength_*a; | |
320 | |||
321 | 3 | auto firstUnitAxis = firstAxis; firstUnitAxis /= a; | |
322 | 3 | auto secondUnitAxis = secondAxis; secondUnitAxis /= b; | |
323 | 3 | const auto normal = crossProduct(firstUnitAxis, secondUnitAxis); | |
324 | |||
325 | 3 | auto zAxis = (topCenter-bottomCenter); | |
326 | 3 | const auto length = zAxis.two_norm(); | |
327 | 3 | zAxis /= length; | |
328 | 3 | const auto height = (zAxis*normal)*length; | |
329 | using std::floor; | ||
330 |
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3 | const std::size_t zSamples = std::max<std::size_t>(floor(height/characteristicLength), 1); |
331 | 3 | const auto zStep = length / Scalar(zSamples); | |
332 | 3 | const auto zStepFactor = length/height; | |
333 | |||
334 | // walk over lattice grid and reject points outside the ellipse | ||
335 | 3 | auto startZ = bottomCenter; | |
336 | 3 | startZ.axpy(0.5*zStep, zAxis); | |
337 |
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6 | auto [ellipseIPs, ellipseIntegrationElement] |
338 | = Detail::ellipseIntegrationPoints(startZ, firstUnitAxis, secondUnitAxis, a, b, normal, characteristicLength); | ||
339 | |||
340 | // compute total number of points | ||
341 |
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3 | const auto abPoints = ellipseIPs.size(); |
342 | 3 | numPoints_ = abPoints*zSamples; | |
343 | |||
344 | // first move in the first layer of ellipse integration points | ||
345 |
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3 | points_.clear(); |
346 |
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3 | points_.reserve(numPoints_); |
347 | 12 | std::move(ellipseIPs.begin(), ellipseIPs.end(), std::back_inserter(points_)); | |
348 | |||
349 | // then extrude along the z axis | ||
350 | 3 | auto zStepVector = zAxis; zStepVector *= zStep; | |
351 |
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100 | for (std::size_t zs = 1; zs < zSamples; ++zs) |
352 |
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485 | std::transform(points_.end() - abPoints, points_.end(), std::back_inserter(points_), |
353 | 269640 | [&](const auto& p){ return p + zStepVector; }); | |
354 | |||
355 | // computation and error correction for integral element to obtain exact integral of constant functions | ||
356 | 3 | integrationElement_ = ellipseIntegrationElement*zStep/zStepFactor; | |
357 | 3 | const auto meanLocalError = (height*a*b*M_PI - integrationElement_*numPoints_)/Scalar(numPoints_); | |
358 | 3 | integrationElement_ += meanLocalError; | |
359 | |||
360 |
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3 | if (verbosity > 0) |
361 | { | ||
362 |
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6 | std::cout << "EllipticCylinderIntegration -- number of integration points: " << numPoints_ <<"\n"; |
363 |
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3 | if (verbosity > 1) |
364 | ✗ | std::cout << " -- a: " << a << ", b: " << b << ", h: " << height << "\n" | |
365 | ✗ | << " -- volume: " << integrationElement_*numPoints_ << " (expected " << height*a*b*M_PI << ")\n" | |
366 | ✗ | << " -- corrected a volume error of: " << meanLocalError/integrationElement_*100 << "%\n"; | |
367 | } | ||
368 | 3 | } | |
369 | |||
370 | //! obtain ith integration element | ||
371 | ✗ | Scalar integrationElement(std::size_t i) const | |
372 | ✗ | { return integrationElement_; } | |
373 | |||
374 | //! obtain ith integration point | ||
375 | const GlobalPosition& integrationPoint(std::size_t i) const | ||
376 | 278208 | { return points_[i]; } | |
377 | |||
378 | //! number of samples points | ||
379 | ✗ | std::size_t size() const | |
380 | ✗ | { return numPoints_; } | |
381 | |||
382 | private: | ||
383 | const Scalar relCharLength_; | ||
384 | std::size_t numPoints_; | ||
385 | Scalar integrationElement_; | ||
386 | std::vector<GlobalPosition> points_; | ||
387 | }; | ||
388 | |||
389 | /*! | ||
390 | * \ingroup EmbeddedCoupling | ||
391 | * \brief Helper class to integrate over an elliptic domain | ||
392 | * \note This is mostly useful if the integral is known and the | ||
393 | * integral mass has to be locally distributed to some non-matching domain | ||
394 | * \note The algorithm is based on evenly spaced area elements with rejection sampling. | ||
395 | * To improve the quality of the integral, increase the sample size. | ||
396 | * \note The area integral of a constant function is exact | ||
397 | * See Koch et al. (2020) https://doi.org/10.1016/j.jcp.2020.109369 | ||
398 | */ | ||
399 | template<class Scalar> | ||
400 |
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6 | class EllipseIntegration |
401 | { | ||
402 | using GlobalPosition = Dune::FieldVector<Scalar, 3>; | ||
403 | |||
404 | public: | ||
405 | /*! | ||
406 | * \brief Constructor | ||
407 | * \param relCharLength characteristic relative integration length (real number between 0 and 1) | ||
408 | * \note half the characteristic length means 2*2=4 times more integration points | ||
409 | */ | ||
410 | 3 | explicit EllipseIntegration(const Scalar relCharLength) | |
411 |
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6 | : relCharLength_(relCharLength) |
412 | {} | ||
413 | |||
414 | /*! | ||
415 | * \brief set geometry of an ellipse | ||
416 | * \param center the center position | ||
417 | * \param firstAxis first ellipse axis (length corresponding to axis length) | ||
418 | * \param secondAxis second ellipse axis (length corresponding to axis length) | ||
419 | * \param verbosity the verbosity level (default: 0 -> no terminal output) | ||
420 | */ | ||
421 | 3 | void setGeometry(const GlobalPosition& center, | |
422 | const GlobalPosition& firstAxis, | ||
423 | const GlobalPosition& secondAxis, | ||
424 | int verbosity = 0) | ||
425 | { | ||
426 | 3 | const auto a = firstAxis.two_norm(); | |
427 | 3 | const auto b = secondAxis.two_norm(); | |
428 | 3 | const auto characteristicLength = relCharLength_*a; | |
429 | |||
430 | 3 | auto firstUnitAxis = firstAxis; firstUnitAxis /= a; | |
431 | 3 | auto secondUnitAxis = secondAxis; secondUnitAxis /= b; | |
432 | 3 | const auto normal = crossProduct(firstUnitAxis, secondUnitAxis); | |
433 | |||
434 | // generate integration points | ||
435 | 3 | std::tie(points_, integrationElement_) | |
436 |
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3 | = Detail::ellipseIntegrationPoints(center, firstUnitAxis, secondUnitAxis, a, b, normal, characteristicLength); |
437 | |||
438 | // store number of sample points | ||
439 |
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3 | const auto abPoints = points_.size(); |
440 | 3 | numPoints_ = abPoints; | |
441 | |||
442 | // computation and error correction for integral element to obtain exact integral of constant functions | ||
443 | 3 | const auto meanLocalError = (a*b*M_PI - integrationElement_*numPoints_)/Scalar(numPoints_); | |
444 | 3 | integrationElement_ += meanLocalError; | |
445 | |||
446 |
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3 | if (verbosity > 0) |
447 | { | ||
448 | 6 | std::cout << "EllipseIntegration -- number of integration points: " << numPoints_ << "\n"; | |
449 |
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3 | if (verbosity > 1) |
450 | ✗ | std::cout << " -- a: " << a << ", b: " << b << "\n" | |
451 | ✗ | << " -- area: " << integrationElement_*numPoints_ << " (expected " << a*b*M_PI << ")\n" | |
452 | ✗ | << " -- corrected an area error of: " << meanLocalError/integrationElement_*100 << "%\n"; | |
453 | } | ||
454 | 3 | } | |
455 | |||
456 | //! obtain ith integration element | ||
457 | ✗ | Scalar integrationElement(std::size_t i) const | |
458 | ✗ | { return integrationElement_; } | |
459 | |||
460 | //! obtain ith integration point | ||
461 | const GlobalPosition& integrationPoint(std::size_t i) const | ||
462 | 8568 | { return points_[i]; } | |
463 | |||
464 | //! number of integration points | ||
465 | ✗ | std::size_t size() const | |
466 | ✗ | { return numPoints_; } | |
467 | |||
468 | private: | ||
469 | const Scalar relCharLength_; | ||
470 | std::size_t numPoints_; | ||
471 | Scalar integrationElement_; | ||
472 | std::vector<GlobalPosition> points_; | ||
473 | }; | ||
474 | |||
475 | } // end namespace Dumux::EmbeddedCoupling | ||
476 | |||
477 | #endif | ||
478 |