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openmc-dev / openmc / 21492883686

29 Jan 2026 08:02PM UTC coverage: 81.749% (-0.2%) from 81.993%
21492883686

Pull #3756

github

web-flow
Merge 7d830ab98 into f7a734189
Pull Request #3756: Refactor ParticleType to use PDG Monte Carlo numbering scheme

17298 of 24251 branches covered (71.33%)

Branch coverage included in aggregate %.

346 of 501 new or added lines in 32 files covered. (69.06%)

453 existing lines in 6 files now uncovered.

55889 of 65276 relevant lines covered (85.62%)

44298457.78 hits per line

Source File
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85.26
/src/particle.cpp
1
#include "openmc/particle.h"
2

3
#include <algorithm> // copy, min
4
#include <cmath>     // log, abs
5

6
#include <fmt/core.h>
7

8
#include "openmc/bank.h"
9
#include "openmc/capi.h"
10
#include "openmc/cell.h"
11
#include "openmc/collision_track.h"
12
#include "openmc/constants.h"
13
#include "openmc/dagmc.h"
14
#include "openmc/error.h"
15
#include "openmc/geometry.h"
16
#include "openmc/hdf5_interface.h"
17
#include "openmc/material.h"
18
#include "openmc/message_passing.h"
19
#include "openmc/mgxs_interface.h"
20
#include "openmc/nuclide.h"
21
#include "openmc/particle_data.h"
22
#include "openmc/photon.h"
23
#include "openmc/physics.h"
24
#include "openmc/physics_mg.h"
25
#include "openmc/random_lcg.h"
26
#include "openmc/settings.h"
27
#include "openmc/simulation.h"
28
#include "openmc/source.h"
29
#include "openmc/surface.h"
30
#include "openmc/tallies/derivative.h"
31
#include "openmc/tallies/tally.h"
32
#include "openmc/tallies/tally_scoring.h"
33
#include "openmc/track_output.h"
34
#include "openmc/weight_windows.h"
35

36
#ifdef OPENMC_DAGMC_ENABLED
37
#include "DagMC.hpp"
38
#endif
39

40
namespace openmc {
41

42
//==============================================================================
43
// Particle implementation
44
//==============================================================================
45

46
double Particle::speed() const
2,147,483,647✔
47
{
48
  if (settings::run_CE) {
2,147,483,647✔
49
    // Determine mass in eV/c^2
50
    double mass;
51
    switch (this->type().pdg_number()) {
2,114,217,584!
52
    case PDG_NEUTRON:
2,038,962,250✔
53
      mass = MASS_NEUTRON_EV;
2,038,962,250✔
54
      break;
2,038,962,250✔
55
    case PDG_PHOTON:
21,805,037✔
56
      mass = 0.0;
21,805,037✔
57
      break;
21,805,037✔
58
    case PDG_ELECTRON:
53,450,297✔
59
    case PDG_POSITRON:
60
      mass = MASS_ELECTRON_EV;
53,450,297✔
61
      break;
53,450,297✔
NEW
62
    default:
×
NEW
63
      fatal_error("Unsupported particle for speed calculation.");
×
64
    }
65
    // Equivalent to C * sqrt(1-(m/(m+E))^2) without problem at E<<m:
66
    return C_LIGHT * std::sqrt(this->E() * (this->E() + 2 * mass)) /
2,114,217,584✔
67
           (this->E() + mass);
2,114,217,584✔
68
  } else {
69
    auto& macro_xs = data::mg.macro_xs_[this->material()];
2,063,937,414✔
70
    int macro_t = this->mg_xs_cache().t;
2,063,937,414✔
71
    int macro_a = macro_xs.get_angle_index(this->u());
2,063,937,414✔
72
    return 1.0 / macro_xs.get_xs(MgxsType::INVERSE_VELOCITY, this->g(), nullptr,
2,063,937,414✔
73
                   nullptr, nullptr, macro_t, macro_a);
2,063,937,414✔
74
  }
75
}
76

77
bool Particle::create_secondary(
111,499,019✔
78
  double wgt, Direction u, double E, ParticleType type)
79
{
80
  // If energy is below cutoff for this particle, don't create secondary
81
  // particle
82
  int idx = type.transport_index();
111,499,019✔
83
  if (idx == C_NONE) {
111,499,019!
NEW
84
    return false;
×
85
  }
86
  if (E < settings::energy_cutoff[idx]) {
111,499,019✔
87
    return false;
53,297,203✔
88
  }
89

90
  auto& bank = secondary_bank().emplace_back();
58,201,816✔
91
  bank.particle = type;
58,201,816✔
92
  bank.wgt = wgt;
58,201,816✔
93
  bank.r = r();
58,201,816✔
94
  bank.u = u;
58,201,816✔
95
  bank.E = settings::run_CE ? E : g();
58,201,816!
96
  bank.time = time();
58,201,816✔
97
  bank_second_E() += bank.E;
58,201,816✔
98
  return true;
58,201,816✔
99
}
100

101
void Particle::split(double wgt)
4,087,901✔
102
{
103
  auto& bank = secondary_bank().emplace_back();
4,087,901✔
104
  bank.particle = type();
4,087,901✔
105
  bank.wgt = wgt;
4,087,901✔
106
  bank.r = r();
4,087,901✔
107
  bank.u = u();
4,087,901✔
108
  bank.E = settings::run_CE ? E() : g();
4,087,901✔
109
  bank.time = time();
4,087,901✔
110

111
  // Convert signed index to a signed surface ID
112
  if (surface() == SURFACE_NONE) {
4,087,901✔
113
    bank.surf_id = SURFACE_NONE;
4,087,565✔
114
  } else {
115
    int surf_id = model::surfaces[surface_index()]->id_;
336✔
116
    bank.surf_id = (surface() > 0) ? surf_id : -surf_id;
336!
117
  }
118
}
4,087,901✔
119

120
void Particle::from_source(const SourceSite* src)
238,053,630✔
121
{
122
  // Reset some attributes
123
  clear();
238,053,630✔
124
  surface() = SURFACE_NONE;
238,053,630✔
125
  cell_born() = C_NONE;
238,053,630✔
126
  material() = C_NONE;
238,053,630✔
127
  n_collision() = 0;
238,053,630✔
128
  fission() = false;
238,053,630✔
129
  zero_flux_derivs();
238,053,630✔
130
  lifetime() = 0.0;
238,053,630✔
131
#ifdef OPENMC_DAGMC_ENABLED
132
  history().reset();
21,802,791✔
133
#endif
134

135
  // Copy attributes from source bank site
136
  type() = src->particle;
238,053,630✔
137
  wgt() = src->wgt;
238,053,630✔
138
  wgt_last() = src->wgt;
238,053,630✔
139
  r() = src->r;
238,053,630✔
140
  u() = src->u;
238,053,630✔
141
  r_born() = src->r;
238,053,630✔
142
  r_last_current() = src->r;
238,053,630✔
143
  r_last() = src->r;
238,053,630✔
144
  u_last() = src->u;
238,053,630✔
145
  if (settings::run_CE) {
238,053,630✔
146
    E() = src->E;
122,315,013✔
147
    g() = 0;
122,315,013✔
148
  } else {
149
    g() = static_cast<int>(src->E);
115,738,617✔
150
    g_last() = static_cast<int>(src->E);
115,738,617✔
151
    E() = data::mg.energy_bin_avg_[g()];
115,738,617✔
152
  }
153
  E_last() = E();
238,053,630✔
154
  time() = src->time;
238,053,630✔
155
  time_last() = src->time;
238,053,630✔
156
  parent_nuclide() = src->parent_nuclide;
238,053,630✔
157
  delayed_group() = src->delayed_group;
238,053,630✔
158

159
  // Convert signed surface ID to signed index
160
  if (src->surf_id != SURFACE_NONE) {
238,053,630✔
161
    int index_plus_one = model::surface_map[std::abs(src->surf_id)] + 1;
110,336✔
162
    surface() = (src->surf_id > 0) ? index_plus_one : -index_plus_one;
110,336!
163
  }
164
}
238,053,630✔
165

166
void Particle::event_calculate_xs()
2,147,483,647✔
167
{
168
  // Set the random number stream
169
  stream() = STREAM_TRACKING;
2,147,483,647✔
170

171
  // Store pre-collision particle properties
172
  wgt_last() = wgt();
2,147,483,647✔
173
  E_last() = E();
2,147,483,647✔
174
  u_last() = u();
2,147,483,647✔
175
  r_last() = r();
2,147,483,647✔
176
  time_last() = time();
2,147,483,647✔
177

178
  // Reset event variables
179
  event() = TallyEvent::KILL;
2,147,483,647✔
180
  event_nuclide() = NUCLIDE_NONE;
2,147,483,647✔
181
  event_mt() = REACTION_NONE;
2,147,483,647✔
182

183
  // If the cell hasn't been determined based on the particle's location,
184
  // initiate a search for the current cell. This generally happens at the
185
  // beginning of the history and again for any secondary particles
186
  if (lowest_coord().cell() == C_NONE) {
2,147,483,647✔
187
    if (!exhaustive_find_cell(*this)) {
229,569,721!
188
      mark_as_lost(
×
189
        "Could not find the cell containing particle " + std::to_string(id()));
×
190
      return;
×
191
    }
192

193
    // Set birth cell attribute
194
    if (cell_born() == C_NONE)
229,569,721!
195
      cell_born() = lowest_coord().cell();
229,569,721✔
196

197
    // Initialize last cells from current cell
198
    for (int j = 0; j < n_coord(); ++j) {
476,164,122✔
199
      cell_last(j) = coord(j).cell();
246,594,401✔
200
    }
201
    n_coord_last() = n_coord();
229,569,721✔
202
  }
203

204
  // Write particle track.
205
  if (write_track())
2,147,483,647✔
206
    write_particle_track(*this);
10,822✔
207

208
  if (settings::check_overlaps)
2,147,483,647!
209
    check_cell_overlap(*this);
×
210

211
  // Calculate microscopic and macroscopic cross sections
212
  if (material() != MATERIAL_VOID) {
2,147,483,647✔
213
    if (settings::run_CE) {
2,147,483,647✔
214
      if (material() != material_last() || sqrtkT() != sqrtkT_last() ||
2,147,483,647✔
215
          density_mult() != density_mult_last()) {
365,032,697✔
216
        // If the material is the same as the last material and the
217
        // temperature hasn't changed, we don't need to lookup cross
218
        // sections again.
219
        model::materials[material()]->calculate_xs(*this);
1,609,922,796✔
220
      }
221
    } else {
222
      // Get the MG data; unlike the CE case above, we have to re-calculate
223
      // cross sections for every collision since the cross sections may
224
      // be angle-dependent
225
      data::mg.macro_xs_[material()].calculate_xs(*this);
2,063,937,414✔
226

227
      // Update the particle's group while we know we are multi-group
228
      g_last() = g();
2,063,937,414✔
229
    }
230
  } else {
231
    macro_xs().total = 0.0;
111,825,022✔
232
    macro_xs().absorption = 0.0;
111,825,022✔
233
    macro_xs().fission = 0.0;
111,825,022✔
234
    macro_xs().nu_fission = 0.0;
111,825,022✔
235
  }
236
}
237

238
void Particle::event_advance()
2,147,483,647✔
239
{
240
  // Find the distance to the nearest boundary
241
  boundary() = distance_to_boundary(*this);
2,147,483,647✔
242

243
  // Sample a distance to collision
244
  if (type() == ParticleType::electron() ||
2,147,483,647✔
245
      type() == ParticleType::positron()) {
2,147,483,647✔
246
    collision_distance() = material() == MATERIAL_VOID ? INFINITY : 0.0;
53,450,297!
247
  } else if (macro_xs().total == 0.0) {
2,147,483,647✔
248
    collision_distance() = INFINITY;
111,825,022✔
249
  } else {
250
    collision_distance() = -std::log(prn(current_seed())) / macro_xs().total;
2,147,483,647✔
251
  }
252

253
  double speed = this->speed();
2,147,483,647✔
254
  double time_cutoff = settings::time_cutoff[type().transport_index()];
2,147,483,647✔
255
  double distance_cutoff =
256
    (time_cutoff < INFTY) ? (time_cutoff - time()) * speed : INFTY;
2,147,483,647✔
257

258
  // Select smaller of the three distances
259
  double distance =
260
    std::min({boundary().distance(), collision_distance(), distance_cutoff});
2,147,483,647✔
261

262
  // Advance particle in space and time
263
  this->move_distance(distance);
2,147,483,647✔
264
  double dt = distance / speed;
2,147,483,647✔
265
  this->time() += dt;
2,147,483,647✔
266
  this->lifetime() += dt;
2,147,483,647✔
267

268
  // Score timed track-length tallies
269
  if (!model::active_timed_tracklength_tallies.empty()) {
2,147,483,647✔
270
    score_timed_tracklength_tally(*this, distance);
3,628,317✔
271
  }
272

273
  // Score track-length tallies
274
  if (!model::active_tracklength_tallies.empty()) {
2,147,483,647✔
275
    score_tracklength_tally(*this, distance);
1,562,730,039✔
276
  }
277

278
  // Score track-length estimate of k-eff
279
  if (settings::run_mode == RunMode::EIGENVALUE && type().is_neutron()) {
2,147,483,647✔
280
    keff_tally_tracklength() += wgt() * distance * macro_xs().nu_fission;
2,147,483,647✔
281
  }
282

283
  // Score flux derivative accumulators for differential tallies.
284
  if (!model::active_tallies.empty()) {
2,147,483,647✔
285
    score_track_derivative(*this, distance);
1,732,172,662✔
286
  }
287

288
  // Set particle weight to zero if it hit the time boundary
289
  if (distance == distance_cutoff) {
2,147,483,647✔
290
    wgt() = 0.0;
224,928✔
291
  }
292
}
2,147,483,647✔
293

294
void Particle::event_cross_surface()
2,147,483,647✔
295
{
296
  // Saving previous cell data
297
  for (int j = 0; j < n_coord(); ++j) {
2,147,483,647✔
298
    cell_last(j) = coord(j).cell();
2,147,483,647✔
299
  }
300
  n_coord_last() = n_coord();
2,147,483,647✔
301

302
  // Set surface that particle is on and adjust coordinate levels
303
  surface() = boundary().surface();
2,147,483,647✔
304
  n_coord() = boundary().coord_level();
2,147,483,647✔
305

306
  if (boundary().lattice_translation()[0] != 0 ||
2,147,483,647✔
307
      boundary().lattice_translation()[1] != 0 ||
2,147,483,647✔
308
      boundary().lattice_translation()[2] != 0) {
1,695,546,775✔
309
    // Particle crosses lattice boundary
310

311
    bool verbose = settings::verbosity >= 10 || trace();
732,435,491!
312
    cross_lattice(*this, boundary(), verbose);
732,435,491✔
313
    event() = TallyEvent::LATTICE;
732,435,491✔
314
  } else {
315
    // Particle crosses surface
316
    const auto& surf {model::surfaces[surface_index()].get()};
1,507,004,913✔
317
    // If BC, add particle to surface source before crossing surface
318
    if (surf->surf_source_ && surf->bc_) {
1,507,004,913✔
319
      add_surf_source_to_bank(*this, *surf);
688,545,425✔
320
    }
321
    this->cross_surface(*surf);
1,507,004,913✔
322
    // If no BC, add particle to surface source after crossing surface
323
    if (surf->surf_source_ && !surf->bc_) {
1,507,004,904✔
324
      add_surf_source_to_bank(*this, *surf);
817,221,652✔
325
    }
326
    if (settings::weight_window_checkpoint_surface) {
1,507,004,904✔
327
      apply_weight_windows(*this);
10,738!
328
    }
329
    event() = TallyEvent::SURFACE;
1,507,004,904✔
330
  }
331
  // Score cell to cell partial currents
332
  if (!model::active_surface_tallies.empty()) {
2,147,483,647✔
333
    score_surface_tally(*this, model::active_surface_tallies);
34,922,767✔
334
  }
335
}
2,147,483,647✔
336

337
void Particle::event_collide()
2,147,483,647✔
338
{
339
  // Score collision estimate of keff
340
  if (settings::run_mode == RunMode::EIGENVALUE && type().is_neutron()) {
2,147,483,647✔
341
    keff_tally_collision() += wgt() * macro_xs().nu_fission / macro_xs().total;
2,125,051,591✔
342
  }
343

344
  // Score surface current tallies -- this has to be done before the collision
345
  // since the direction of the particle will change and we need to use the
346
  // pre-collision direction to figure out what mesh surfaces were crossed
347

348
  if (!model::active_meshsurf_tallies.empty())
2,147,483,647✔
349
    score_surface_tally(*this, model::active_meshsurf_tallies);
63,098,926✔
350

351
  // Clear surface component
352
  surface() = SURFACE_NONE;
2,147,483,647✔
353

354
  if (settings::run_CE) {
2,147,483,647✔
355
    collision(*this);
943,978,342✔
356
  } else {
357
    collision_mg(*this);
1,783,060,477✔
358
  }
359

360
  // Collision track feature to recording particle interaction
361
  if (settings::collision_track) {
2,147,483,647✔
362
    collision_track_record(*this);
150,087✔
363
  }
364

365
  // Score collision estimator tallies -- this is done after a collision
366
  // has occurred rather than before because we need information on the
367
  // outgoing energy for any tallies with an outgoing energy filter
368
  if (!model::active_collision_tallies.empty())
2,147,483,647✔
369
    score_collision_tally(*this);
107,041,058✔
370
  if (!model::active_analog_tallies.empty()) {
2,147,483,647✔
371
    if (settings::run_CE) {
291,821,708✔
372
      score_analog_tally_ce(*this);
290,613,446✔
373
    } else {
374
      score_analog_tally_mg(*this);
1,208,262✔
375
    }
376
  }
377

378
  if (!model::active_pulse_height_tallies.empty() && type().is_photon()) {
2,147,483,647✔
379
    pht_collision_energy();
2,024✔
380
  }
381

382
  // Reset banked weight during collision
383
  n_bank() = 0;
2,147,483,647✔
384
  bank_second_E() = 0.0;
2,147,483,647✔
385
  wgt_bank() = 0.0;
2,147,483,647✔
386
  zero_delayed_bank();
2,147,483,647✔
387

388
  // Reset fission logical
389
  fission() = false;
2,147,483,647✔
390

391
  // Save coordinates for tallying purposes
392
  r_last_current() = r();
2,147,483,647✔
393

394
  // Set last material to none since cross sections will need to be
395
  // re-evaluated
396
  material_last() = C_NONE;
2,147,483,647✔
397

398
  // Set all directions to base level -- right now, after a collision, only
399
  // the base level directions are changed
400
  for (int j = 0; j < n_coord() - 1; ++j) {
2,147,483,647✔
401
    if (coord(j + 1).rotated()) {
143,189,203✔
402
      // If next level is rotated, apply rotation matrix
403
      const auto& m {model::cells[coord(j).cell()]->rotation_};
10,426,614✔
404
      const auto& u {coord(j).u()};
10,426,614✔
405
      coord(j + 1).u() = u.rotate(m);
10,426,614✔
406
    } else {
407
      // Otherwise, copy this level's direction
408
      coord(j + 1).u() = coord(j).u();
132,762,589✔
409
    }
410
  }
411

412
  // Score flux derivative accumulators for differential tallies.
413
  if (!model::active_tallies.empty())
2,147,483,647✔
414
    score_collision_derivative(*this);
816,342,483✔
415

416
#ifdef OPENMC_DAGMC_ENABLED
417
  history().reset();
250,250,527✔
418
#endif
419
}
2,147,483,647✔
420

421
void Particle::event_revive_from_secondary()
2,147,483,647✔
422
{
423
  // If particle has too many events, display warning and kill it
424
  ++n_event();
2,147,483,647✔
425
  if (n_event() == settings::max_particle_events) {
2,147,483,647!
426
    warning("Particle " + std::to_string(id()) +
×
427
            " underwent maximum number of events.");
428
    wgt() = 0.0;
×
429
  }
430

431
  // Check for secondary particles if this particle is dead
432
  if (!alive()) {
2,147,483,647✔
433
    // Write final position for this particle
434
    if (write_track()) {
229,569,317✔
435
      write_particle_track(*this);
6,678✔
436
    }
437

438
    // If no secondary particles, break out of event loop
439
    if (secondary_bank().empty())
229,569,317✔
440
      return;
167,076,081✔
441

442
    from_source(&secondary_bank().back());
62,493,236✔
443
    secondary_bank().pop_back();
62,493,236✔
444
    n_event() = 0;
62,493,236✔
445
    bank_second_E() = 0.0;
62,493,236✔
446

447
    // Subtract secondary particle energy from interim pulse-height results
448
    if (!model::active_pulse_height_tallies.empty() &&
62,508,735✔
449
        this->type().is_photon()) {
15,499✔
450
      // Since the birth cell of the particle has not been set we
451
      // have to determine it before the energy of the secondary particle can be
452
      // removed from the pulse-height of this cell.
453
      if (lowest_coord().cell() == C_NONE) {
605!
454
        bool verbose = settings::verbosity >= 10 || trace();
605!
455
        if (!exhaustive_find_cell(*this, verbose)) {
605!
456
          mark_as_lost("Could not find the cell containing particle " +
×
457
                       std::to_string(id()));
×
458
          return;
×
459
        }
460
        // Set birth cell attribute
461
        if (cell_born() == C_NONE)
605!
462
          cell_born() = lowest_coord().cell();
605✔
463

464
        // Initialize last cells from current cell
465
        for (int j = 0; j < n_coord(); ++j) {
1,210✔
466
          cell_last(j) = coord(j).cell();
605✔
467
        }
468
        n_coord_last() = n_coord();
605✔
469
      }
470
      pht_secondary_particles();
605✔
471
    }
472

473
    // Enter new particle in particle track file
474
    if (write_track())
62,493,236✔
475
      add_particle_track(*this);
5,608✔
476
  }
477
}
478

479
void Particle::event_death()
167,077,081✔
480
{
481
#ifdef OPENMC_DAGMC_ENABLED
482
  history().reset();
15,264,135✔
483
#endif
484

485
  // Finish particle track output.
486
  if (write_track()) {
167,077,081✔
487
    finalize_particle_track(*this);
1,070✔
488
  }
489

490
// Contribute tally reduction variables to global accumulator
491
#pragma omp atomic
92,182,101✔
492
  global_tally_absorption += keff_tally_absorption();
167,077,081✔
493
#pragma omp atomic
92,357,336✔
494
  global_tally_collision += keff_tally_collision();
167,077,081✔
495
#pragma omp atomic
91,962,780✔
496
  global_tally_tracklength += keff_tally_tracklength();
167,077,081✔
497
#pragma omp atomic
91,354,574✔
498
  global_tally_leakage += keff_tally_leakage();
167,077,081✔
499

500
  // Reset particle tallies once accumulated
501
  keff_tally_absorption() = 0.0;
167,077,081✔
502
  keff_tally_collision() = 0.0;
167,077,081✔
503
  keff_tally_tracklength() = 0.0;
167,077,081✔
504
  keff_tally_leakage() = 0.0;
167,077,081✔
505

506
  if (!model::active_pulse_height_tallies.empty()) {
167,077,081✔
507
    score_pulse_height_tally(*this, model::active_pulse_height_tallies);
5,500✔
508
  }
509

510
  // Record the number of progeny created by this particle.
511
  // This data will be used to efficiently sort the fission bank.
512
  if (settings::run_mode == RunMode::EIGENVALUE) {
167,077,081✔
513
    int64_t offset = id() - 1 - simulation::work_index[mpi::rank];
140,925,700✔
514
    simulation::progeny_per_particle[offset] = n_progeny();
140,925,700✔
515
  }
516
}
167,077,081✔
517

518
void Particle::pht_collision_energy()
2,024✔
519
{
520
  // Adds the energy particles lose in a collision to the pulse-height
521

522
  // determine index of cell in pulse_height_cells
523
  auto it = std::find(model::pulse_height_cells.begin(),
2,024✔
524
    model::pulse_height_cells.end(), lowest_coord().cell());
2,024✔
525

526
  if (it != model::pulse_height_cells.end()) {
2,024!
527
    int index = std::distance(model::pulse_height_cells.begin(), it);
2,024✔
528
    pht_storage()[index] += E_last() - E();
2,024✔
529

530
    // If the energy of the particle is below the cutoff, it will not be sampled
531
    // so its energy is added to the pulse-height in the cell
532
    int photon = ParticleType::photon().transport_index();
2,024✔
533
    if (E() < settings::energy_cutoff[photon]) {
2,024✔
534
      pht_storage()[index] += E();
825✔
535
    }
536
  }
537
}
2,024✔
538

539
void Particle::pht_secondary_particles()
605✔
540
{
541
  // Removes the energy of secondary produced particles from the pulse-height
542

543
  // determine index of cell in pulse_height_cells
544
  auto it = std::find(model::pulse_height_cells.begin(),
605✔
545
    model::pulse_height_cells.end(), cell_born());
605✔
546

547
  if (it != model::pulse_height_cells.end()) {
605!
548
    int index = std::distance(model::pulse_height_cells.begin(), it);
605✔
549
    pht_storage()[index] -= E();
605✔
550
  }
551
}
605✔
552

553
void Particle::cross_surface(const Surface& surf)
1,508,824,075✔
554
{
555

556
  if (settings::verbosity >= 10 || trace()) {
1,508,824,075✔
557
    write_message(1, "    Crossing surface {}", surf.id_);
33✔
558
  }
559

560
// if we're crossing a CSG surface, make sure the DAG history is reset
561
#ifdef OPENMC_DAGMC_ENABLED
562
  if (surf.geom_type() == GeometryType::CSG)
137,897,427✔
563
    history().reset();
137,842,308✔
564
#endif
565

566
  // Handle any applicable boundary conditions.
567
  if (surf.bc_ && settings::run_mode != RunMode::PLOTTING &&
2,147,483,647!
568
      settings::run_mode != RunMode::VOLUME) {
689,017,477✔
569
    surf.bc_->handle_particle(*this, surf);
688,897,533✔
570
    return;
688,897,533✔
571
  }
572

573
  // ==========================================================================
574
  // SEARCH NEIGHBOR LISTS FOR NEXT CELL
575

576
#ifdef OPENMC_DAGMC_ENABLED
577
  // in DAGMC, we know what the next cell should be
578
  if (surf.geom_type() == GeometryType::DAG) {
74,826,950✔
579
    int32_t i_cell = next_cell(surface_index(), cell_last(n_coord() - 1),
44,310✔
580
                       lowest_coord().universe()) -
44,310✔
581
                     1;
44,310✔
582
    // save material, temperature, and density multiplier
583
    material_last() = material();
44,310✔
584
    sqrtkT_last() = sqrtkT();
44,310✔
585
    density_mult_last() = density_mult();
44,310✔
586
    // set new cell value
587
    lowest_coord().cell() = i_cell;
44,310✔
588
    auto& cell = model::cells[i_cell];
44,310✔
589

590
    cell_instance() = 0;
44,310✔
591
    if (cell->distribcell_index_ >= 0)
44,310✔
592
      cell_instance() = cell_instance_at_level(*this, n_coord() - 1);
43,286✔
593

594
    material() = cell->material(cell_instance());
44,310✔
595
    sqrtkT() = cell->sqrtkT(cell_instance());
44,310✔
596
    density_mult() = cell->density_mult(cell_instance());
44,310✔
597
    return;
44,310✔
598
  }
599
#endif
600

601
  bool verbose = settings::verbosity >= 10 || trace();
819,882,232!
602
  if (neighbor_list_find_cell(*this, verbose)) {
819,882,232✔
603
    return;
819,852,321✔
604
  }
605

606
  // ==========================================================================
607
  // COULDN'T FIND PARTICLE IN NEIGHBORING CELLS, SEARCH ALL CELLS
608

609
  // Remove lower coordinate levels
610
  n_coord() = 1;
29,911✔
611
  bool found = exhaustive_find_cell(*this, verbose);
29,911✔
612

613
  if (settings::run_mode != RunMode::PLOTTING && (!found)) {
29,911!
614
    // If a cell is still not found, there are two possible causes: 1) there is
615
    // a void in the model, and 2) the particle hit a surface at a tangent. If
616
    // the particle is really traveling tangent to a surface, if we move it
617
    // forward a tiny bit it should fix the problem.
618

619
    surface() = SURFACE_NONE;
5,799✔
620
    n_coord() = 1;
5,799✔
621
    r() += TINY_BIT * u();
5,799✔
622

623
    // Couldn't find next cell anywhere! This probably means there is an actual
624
    // undefined region in the geometry.
625

626
    if (!exhaustive_find_cell(*this, verbose)) {
5,799!
627
      mark_as_lost("After particle " + std::to_string(id()) +
17,388✔
628
                   " crossed surface " + std::to_string(surf.id_) +
23,178✔
629
                   " it could not be located in any cell and it did not leak.");
630
      return;
5,790✔
631
    }
632
  }
633
}
634

635
void Particle::cross_vacuum_bc(const Surface& surf)
35,018,997✔
636
{
637
  // Score any surface current tallies -- note that the particle is moved
638
  // forward slightly so that if the mesh boundary is on the surface, it is
639
  // still processed
640

641
  if (!model::active_meshsurf_tallies.empty()) {
35,018,997✔
642
    // TODO: Find a better solution to score surface currents than
643
    // physically moving the particle forward slightly
644

645
    r() += TINY_BIT * u();
937,222✔
646
    score_surface_tally(*this, model::active_meshsurf_tallies);
937,222✔
647
  }
648

649
  // Score to global leakage tally
650
  keff_tally_leakage() += wgt();
35,018,997✔
651

652
  // Kill the particle
653
  wgt() = 0.0;
35,018,997✔
654

655
  // Display message
656
  if (settings::verbosity >= 10 || trace()) {
35,018,997!
657
    write_message(1, "    Leaked out of surface {}", surf.id_);
11✔
658
  }
659
}
35,018,997✔
660

661
void Particle::cross_reflective_bc(const Surface& surf, Direction new_u)
652,640,003✔
662
{
663
  // Do not handle reflective boundary conditions on lower universes
664
  if (n_coord() != 1) {
652,640,003!
665
    mark_as_lost("Cannot reflect particle " + std::to_string(id()) +
×
666
                 " off surface in a lower universe.");
667
    return;
×
668
  }
669

670
  // Score surface currents since reflection causes the direction of the
671
  // particle to change. For surface filters, we need to score the tallies
672
  // twice, once before the particle's surface attribute has changed and
673
  // once after. For mesh surface filters, we need to artificially move
674
  // the particle slightly back in case the surface crossing is coincident
675
  // with a mesh boundary
676

677
  if (!model::active_surface_tallies.empty()) {
652,640,003✔
678
    score_surface_tally(*this, model::active_surface_tallies);
285,021✔
679
  }
680

681
  if (!model::active_meshsurf_tallies.empty()) {
652,640,003✔
682
    Position r {this->r()};
46,885,487✔
683
    this->r() -= TINY_BIT * u();
46,885,487✔
684
    score_surface_tally(*this, model::active_meshsurf_tallies);
46,885,487✔
685
    this->r() = r;
46,885,487✔
686
  }
687

688
  // Set the new particle direction
689
  u() = new_u;
652,640,003✔
690

691
  // Reassign particle's cell and surface
692
  coord(0).cell() = cell_last(0);
652,640,003✔
693
  surface() = -surface();
652,640,003✔
694

695
  // If a reflective surface is coincident with a lattice or universe
696
  // boundary, it is necessary to redetermine the particle's coordinates in
697
  // the lower universes.
698
  // (unless we're using a dagmc model, which has exactly one universe)
699
  n_coord() = 1;
652,640,003✔
700
  if (surf.geom_type() != GeometryType::DAG &&
1,305,277,248!
701
      !neighbor_list_find_cell(*this)) {
652,637,245!
702
    mark_as_lost("Couldn't find particle after reflecting from surface " +
×
703
                 std::to_string(surf.id_) + ".");
×
704
    return;
×
705
  }
706

707
  // Set previous coordinate going slightly past surface crossing
708
  r_last_current() = r() + TINY_BIT * u();
652,640,003✔
709

710
  // Diagnostic message
711
  if (settings::verbosity >= 10 || trace()) {
652,640,003!
712
    write_message(1, "    Reflected from surface {}", surf.id_);
×
713
  }
714
}
715

716
void Particle::cross_periodic_bc(
2,243,999✔
717
  const Surface& surf, Position new_r, Direction new_u, int new_surface)
718
{
719
  // Do not handle periodic boundary conditions on lower universes
720
  if (n_coord() != 1) {
2,243,999!
721
    mark_as_lost(
×
722
      "Cannot transfer particle " + std::to_string(id()) +
×
723
      " across surface in a lower universe. Boundary conditions must be "
724
      "applied to root universe.");
725
    return;
×
726
  }
727

728
  // Score surface currents since reflection causes the direction of the
729
  // particle to change -- artificially move the particle slightly back in
730
  // case the surface crossing is coincident with a mesh boundary
731
  if (!model::active_meshsurf_tallies.empty()) {
2,243,999!
732
    Position r {this->r()};
×
733
    this->r() -= TINY_BIT * u();
×
734
    score_surface_tally(*this, model::active_meshsurf_tallies);
×
735
    this->r() = r;
×
736
  }
737

738
  // Adjust the particle's location and direction.
739
  r() = new_r;
2,243,999✔
740
  u() = new_u;
2,243,999✔
741

742
  // Reassign particle's surface
743
  surface() = new_surface;
2,243,999✔
744

745
  // Figure out what cell particle is in now
746
  n_coord() = 1;
2,243,999✔
747

748
  if (!neighbor_list_find_cell(*this)) {
2,243,999!
749
    mark_as_lost("Couldn't find particle after hitting periodic "
×
750
                 "boundary on surface " +
×
751
                 std::to_string(surf.id_) + ".");
×
752
    return;
×
753
  }
754

755
  // Set previous coordinate going slightly past surface crossing
756
  r_last_current() = r() + TINY_BIT * u();
2,243,999✔
757

758
  // Diagnostic message
759
  if (settings::verbosity >= 10 || trace()) {
2,243,999!
760
    write_message(1, "    Hit periodic boundary on surface {}", surf.id_);
×
761
  }
762
}
763

764
void Particle::mark_as_lost(const char* message)
5,799✔
765
{
766
  // Print warning and write lost particle file
767
  warning(message);
5,799✔
768
  if (settings::max_write_lost_particles < 0 ||
5,799✔
769
      simulation::n_lost_particles < settings::max_write_lost_particles) {
5,500✔
770
    write_restart();
379✔
771
  }
772
  // Increment number of lost particles
773
  wgt() = 0.0;
5,799✔
774
#pragma omp atomic
3,154✔
775
  simulation::n_lost_particles += 1;
2,645✔
776

777
  // Count the total number of simulated particles (on this processor)
778
  auto n = simulation::current_batch * settings::gen_per_batch *
5,799✔
779
           simulation::work_per_rank;
780

781
  // Abort the simulation if the maximum number of lost particles has been
782
  // reached
783
  if (simulation::n_lost_particles >= settings::max_lost_particles &&
5,799✔
784
      simulation::n_lost_particles >= settings::rel_max_lost_particles * n) {
9!
785
    fatal_error("Maximum number of lost particles has been reached.");
9✔
786
  }
787
}
5,790✔
788

789
void Particle::write_restart() const
379✔
790
{
791
  // Dont write another restart file if in particle restart mode
792
  if (settings::run_mode == RunMode::PARTICLE)
379✔
793
    return;
22✔
794

795
  // Set up file name
796
  auto filename = fmt::format("{}particle_{}_{}.h5", settings::path_output,
797
    simulation::current_batch, id());
665✔
798

799
#pragma omp critical(WriteParticleRestart)
374✔
800
  {
801
    // Create file
802
    hid_t file_id = file_open(filename, 'w');
357✔
803

804
    // Write filetype and version info
805
    write_attribute(file_id, "filetype", "particle restart");
357✔
806
    write_attribute(file_id, "version", VERSION_PARTICLE_RESTART);
357✔
807
    write_attribute(file_id, "openmc_version", VERSION);
357✔
808
#ifdef GIT_SHA1
809
    write_attr_string(file_id, "git_sha1", GIT_SHA1);
810
#endif
811

812
    // Write data to file
813
    write_dataset(file_id, "current_batch", simulation::current_batch);
357✔
814
    write_dataset(file_id, "generations_per_batch", settings::gen_per_batch);
357✔
815
    write_dataset(file_id, "current_generation", simulation::current_gen);
357✔
816
    write_dataset(file_id, "n_particles", settings::n_particles);
357✔
817
    switch (settings::run_mode) {
357!
818
    case RunMode::FIXED_SOURCE:
225✔
819
      write_dataset(file_id, "run_mode", "fixed source");
225✔
820
      break;
225✔
821
    case RunMode::EIGENVALUE:
132✔
822
      write_dataset(file_id, "run_mode", "eigenvalue");
132✔
823
      break;
132✔
824
    case RunMode::PARTICLE:
×
825
      write_dataset(file_id, "run_mode", "particle restart");
×
826
      break;
×
827
    default:
×
828
      break;
×
829
    }
830
    write_dataset(file_id, "id", id());
357✔
831
    write_dataset(file_id, "type", type().pdg_number());
357✔
832

833
    int64_t i = current_work();
357✔
834
    if (settings::run_mode == RunMode::EIGENVALUE) {
357✔
835
      // take source data from primary bank for eigenvalue simulation
836
      write_dataset(file_id, "weight", simulation::source_bank[i - 1].wgt);
132✔
837
      write_dataset(file_id, "energy", simulation::source_bank[i - 1].E);
132✔
838
      write_dataset(file_id, "xyz", simulation::source_bank[i - 1].r);
132✔
839
      write_dataset(file_id, "uvw", simulation::source_bank[i - 1].u);
132✔
840
      write_dataset(file_id, "time", simulation::source_bank[i - 1].time);
132✔
841
    } else if (settings::run_mode == RunMode::FIXED_SOURCE) {
225!
842
      // re-sample using rng random number seed used to generate source particle
843
      int64_t id = (simulation::total_gen + overall_generation() - 1) *
225✔
844
                     settings::n_particles +
225✔
845
                   simulation::work_index[mpi::rank] + i;
225✔
846
      uint64_t seed = init_seed(id, STREAM_SOURCE);
225✔
847
      // re-sample source site
848
      auto site = sample_external_source(&seed);
225✔
849
      write_dataset(file_id, "weight", site.wgt);
225✔
850
      write_dataset(file_id, "energy", site.E);
225✔
851
      write_dataset(file_id, "xyz", site.r);
225✔
852
      write_dataset(file_id, "uvw", site.u);
225✔
853
      write_dataset(file_id, "time", site.time);
225✔
854
    }
855

856
    // Close file
857
    file_close(file_id);
357✔
858
  } // #pragma omp critical
859
}
357✔
860

861
void Particle::update_neutron_xs(
2,147,483,647✔
862
  int i_nuclide, int i_grid, int i_sab, double sab_frac, double ncrystal_xs)
863
{
864
  // Get microscopic cross section cache
865
  auto& micro = this->neutron_xs(i_nuclide);
2,147,483,647✔
866

867
  // If the cache doesn't match, recalculate micro xs
868
  if (this->E() != micro.last_E || this->sqrtkT() != micro.last_sqrtkT ||
2,147,483,647✔
869
      i_sab != micro.index_sab || sab_frac != micro.sab_frac ||
2,147,483,647✔
870
      ncrystal_xs != micro.ncrystal_xs) {
2,147,483,647!
871
    data::nuclides[i_nuclide]->calculate_xs(i_sab, i_grid, sab_frac, *this);
2,147,483,647✔
872

873
    // If NCrystal is being used, update micro cross section cache
874
    micro.ncrystal_xs = ncrystal_xs;
2,147,483,647✔
875
    if (ncrystal_xs >= 0.0) {
2,147,483,647✔
876
      data::nuclides[i_nuclide]->calculate_elastic_xs(*this);
11,018,953✔
877
      ncrystal_update_micro(ncrystal_xs, micro);
11,018,953✔
878
    }
879
  }
880
}
2,147,483,647✔
881

882
//==============================================================================
883
// Non-method functions
884
//==============================================================================
885
void add_surf_source_to_bank(Particle& p, const Surface& surf)
1,505,767,077✔
886
{
887
  if (simulation::current_batch <= settings::n_inactive ||
2,147,483,647✔
888
      simulation::surf_source_bank.full()) {
1,178,695,451✔
889
    return;
1,505,637,424✔
890
  }
891

892
  // If a cell/cellfrom/cellto parameter is defined
893
  if (settings::ssw_cell_id != C_NONE) {
337,085✔
894

895
    // Retrieve cell index and storage type
896
    int cell_idx = model::cell_map[settings::ssw_cell_id];
254,440✔
897

898
    if (surf.bc_) {
254,440✔
899
      // Leave if cellto with vacuum boundary condition
900
      if (surf.bc_->type() == "vacuum" &&
182,558!
901
          settings::ssw_cell_type == SSWCellType::To) {
33,099✔
902
        return;
12,136✔
903
      }
904

905
      // Leave if other boundary condition than vacuum
906
      if (surf.bc_->type() != "vacuum") {
137,323✔
907
        return;
116,360✔
908
      }
909
    }
910

911
    // Check if the cell of interest has been exited
912
    bool exited = false;
125,944✔
913
    for (int i = 0; i < p.n_coord_last(); ++i) {
333,677✔
914
      if (p.cell_last(i) == cell_idx) {
207,733✔
915
        exited = true;
73,765✔
916
      }
917
    }
918

919
    // Check if the cell of interest has been entered
920
    bool entered = false;
125,944✔
921
    for (int i = 0; i < p.n_coord(); ++i) {
297,979✔
922
      if (p.coord(i).cell() == cell_idx) {
172,035✔
923
        entered = true;
57,517✔
924
      }
925
    }
926

927
    // Vacuum boundary conditions: return if cell is not exited
928
    if (surf.bc_) {
125,944✔
929
      if (surf.bc_->type() == "vacuum" && !exited) {
20,963!
930
        return;
14,663✔
931
      }
932
    } else {
933

934
      // If we both enter and exit the cell of interest
935
      if (entered && exited) {
104,981✔
936
        return;
27,203✔
937
      }
938

939
      // If we did not enter nor exit the cell of interest
940
      if (!entered && !exited) {
77,778✔
941
        return;
13,502✔
942
      }
943

944
      // If cellfrom and the cell before crossing is not the cell of
945
      // interest
946
      if (settings::ssw_cell_type == SSWCellType::From && !exited) {
64,276✔
947
        return;
11,543✔
948
      }
949

950
      // If cellto and the cell after crossing is not the cell of interest
951
      if (settings::ssw_cell_type == SSWCellType::To && !entered) {
52,733✔
952
        return;
12,025✔
953
      }
954
    }
955
  }
956

957
  SourceSite site;
129,653✔
958
  site.r = p.r();
129,653✔
959
  site.u = p.u();
129,653✔
960
  site.E = p.E();
129,653✔
961
  site.time = p.time();
129,653✔
962
  site.wgt = p.wgt();
129,653✔
963
  site.delayed_group = p.delayed_group();
129,653✔
964
  site.surf_id = surf.id_;
129,653✔
965
  site.particle = p.type();
129,653✔
966
  site.parent_id = p.id();
129,653✔
967
  site.progeny_id = p.n_progeny();
129,653✔
968
  int64_t idx = simulation::surf_source_bank.thread_safe_append(site);
129,653✔
969
}
970

971
} // namespace openmc
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