xref: /honee/src/setupts.c (revision fd969b44c9d340fb30c009d929beb19edf2ac3d7)
1 // Copyright (c) 2017-2022, Lawrence Livermore National Security, LLC and other CEED contributors.
2 // All Rights Reserved. See the top-level LICENSE and NOTICE files for details.
3 //
4 // SPDX-License-Identifier: BSD-2-Clause
5 //
6 // This file is part of CEED:  http://github.com/ceed
7 
8 /// @file
9 /// Time-stepping functions for Navier-Stokes example using PETSc
10 
11 #include "../navierstokes.h"
12 #include "../qfunctions/newtonian_state.h"
13 
14 // Compute mass matrix for explicit scheme
15 PetscErrorCode ComputeLumpedMassMatrix(Ceed ceed, DM dm, CeedData ceed_data, Vec M) {
16   Vec           M_loc;
17   CeedQFunction qf_mass;
18   CeedOperator  op_mass;
19   CeedVector    m_ceed, ones_vec;
20   CeedInt       num_comp_q, q_data_size;
21   PetscFunctionBeginUser;
22 
23   // CEED Restriction
24   CeedElemRestrictionGetNumComponents(ceed_data->elem_restr_q, &num_comp_q);
25   CeedElemRestrictionGetNumComponents(ceed_data->elem_restr_qd_i, &q_data_size);
26   CeedElemRestrictionCreateVector(ceed_data->elem_restr_q, &m_ceed, NULL);
27   CeedElemRestrictionCreateVector(ceed_data->elem_restr_q, &ones_vec, NULL);
28   CeedVectorSetValue(ones_vec, 1.0);
29 
30   // CEED QFunction
31   PetscCall(CreateMassQFunction(ceed, num_comp_q, q_data_size, &qf_mass));
32 
33   // CEED Operator
34   CeedOperatorCreate(ceed, qf_mass, NULL, NULL, &op_mass);
35   CeedOperatorSetField(op_mass, "u", ceed_data->elem_restr_q, ceed_data->basis_q, CEED_VECTOR_ACTIVE);
36   CeedOperatorSetField(op_mass, "qdata", ceed_data->elem_restr_qd_i, CEED_BASIS_COLLOCATED, ceed_data->q_data);
37   CeedOperatorSetField(op_mass, "v", ceed_data->elem_restr_q, ceed_data->basis_q, CEED_VECTOR_ACTIVE);
38 
39   // Place PETSc vector in CEED vector
40   PetscMemType m_mem_type;
41   PetscCall(DMGetLocalVector(dm, &M_loc));
42   PetscCall(VecP2C(M_loc, &m_mem_type, m_ceed));
43 
44   // Apply CEED Operator
45   CeedOperatorApply(op_mass, ones_vec, m_ceed, CEED_REQUEST_IMMEDIATE);
46 
47   // Restore vectors
48   PetscCall(VecC2P(m_ceed, m_mem_type, M_loc));
49 
50   // Local-to-Global
51   PetscCall(VecZeroEntries(M));
52   PetscCall(DMLocalToGlobal(dm, M_loc, ADD_VALUES, M));
53   PetscCall(DMRestoreLocalVector(dm, &M_loc));
54 
55   // Invert diagonally lumped mass vector for RHS function
56   PetscCall(VecReciprocal(M));
57 
58   // Cleanup
59   CeedVectorDestroy(&ones_vec);
60   CeedVectorDestroy(&m_ceed);
61   CeedQFunctionDestroy(&qf_mass);
62   CeedOperatorDestroy(&op_mass);
63 
64   PetscFunctionReturn(0);
65 }
66 
67 // Insert Boundary values if it's a new time
68 PetscErrorCode UpdateBoundaryValues(User user, Vec Q_loc, PetscReal t) {
69   PetscFunctionBeginUser;
70   if (user->time_bc_set != t) {
71     PetscCall(DMPlexInsertBoundaryValues(user->dm, PETSC_TRUE, Q_loc, t, NULL, NULL, NULL));
72     user->time_bc_set = t;
73   }
74   PetscFunctionReturn(0);
75 }
76 
77 PetscErrorCode UpdateContextLabel(PetscScalar *previous_value, PetscScalar update_value, CeedOperator op, CeedContextFieldLabel label) {
78   PetscFunctionBeginUser;
79 
80   if (*previous_value != update_value) {
81     if (label) {
82       CeedOperatorContextSetDouble(op, label, &update_value);
83     }
84     *previous_value = update_value;
85   }
86   PetscFunctionReturn(0);
87 }
88 
89 // RHS (Explicit time-stepper) function setup
90 //   This is the RHS of the ODE, given as u_t = G(t,u)
91 //   This function takes in a state vector Q and writes into G
92 PetscErrorCode RHS_NS(TS ts, PetscReal t, Vec Q, Vec G, void *user_data) {
93   User         user = *(User *)user_data;
94   PetscScalar  dt;
95   Vec          Q_loc = user->Q_loc, G_loc;
96   PetscMemType q_mem_type, g_mem_type;
97   PetscFunctionBeginUser;
98 
99   // Get local vector
100   PetscCall(DMGetLocalVector(user->dm, &G_loc));
101 
102   // Update time dependent data
103   PetscCall(UpdateBoundaryValues(user, Q_loc, t));
104   PetscCall(UpdateContextLabel(&user->time, t, user->op_rhs, user->phys->solution_time_label));
105   PetscCall(TSGetTimeStep(ts, &dt));
106   PetscCall(UpdateContextLabel(&user->dt, dt, user->op_rhs, user->phys->timestep_size_label));
107 
108   // Global-to-local
109   PetscCall(DMGlobalToLocal(user->dm, Q, INSERT_VALUES, Q_loc));
110 
111   // Place PETSc vectors in CEED vectors
112   PetscCall(VecReadP2C(Q_loc, &q_mem_type, user->q_ceed));
113   PetscCall(VecP2C(G_loc, &g_mem_type, user->g_ceed));
114 
115   // Apply CEED operator
116   CeedOperatorApply(user->op_rhs, user->q_ceed, user->g_ceed, CEED_REQUEST_IMMEDIATE);
117 
118   // Restore vectors
119   PetscCall(VecReadC2P(user->q_ceed, q_mem_type, Q_loc));
120   PetscCall(VecC2P(user->g_ceed, g_mem_type, G_loc));
121 
122   // Local-to-Global
123   PetscCall(VecZeroEntries(G));
124   PetscCall(DMLocalToGlobal(user->dm, G_loc, ADD_VALUES, G));
125 
126   // Inverse of the lumped mass matrix (M is Minv)
127   PetscCall(VecPointwiseMult(G, G, user->M));
128 
129   // Restore vectors
130   PetscCall(DMRestoreLocalVector(user->dm, &G_loc));
131 
132   PetscFunctionReturn(0);
133 }
134 
135 // Surface forces function setup
136 static PetscErrorCode Surface_Forces_NS(DM dm, Vec G_loc, PetscInt num_walls, const PetscInt walls[], PetscScalar *reaction_force) {
137   DMLabel            face_label;
138   const PetscScalar *g;
139   PetscInt           dim = 3;
140   MPI_Comm           comm;
141 
142   PetscFunctionBeginUser;
143   PetscCall(PetscArrayzero(reaction_force, num_walls * dim));
144   PetscCall(PetscObjectGetComm((PetscObject)dm, &comm));
145   PetscCall(DMGetLabel(dm, "Face Sets", &face_label));
146   PetscCall(VecGetArrayRead(G_loc, &g));
147   for (PetscInt w = 0; w < num_walls; w++) {
148     const PetscInt wall = walls[w];
149     IS             wall_is;
150     PetscCall(DMLabelGetStratumIS(face_label, wall, &wall_is));
151     if (wall_is) {  // There exist such points on this process
152       PetscInt        num_points;
153       const PetscInt *points;
154       PetscCall(ISGetSize(wall_is, &num_points));
155       PetscCall(ISGetIndices(wall_is, &points));
156       for (PetscInt i = 0; i < num_points; i++) {
157         const PetscInt           p = points[i];
158         const StateConservative *r;
159         PetscCall(DMPlexPointLocalRead(dm, p, g, &r));
160         if (!r) continue;
161         for (PetscInt j = 0; j < 3; j++) {
162           reaction_force[w * dim + j] -= r->momentum[j];
163         }
164       }
165       PetscCall(ISRestoreIndices(wall_is, &points));
166     }
167     PetscCall(ISDestroy(&wall_is));
168   }
169   PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, reaction_force, dim * num_walls, MPIU_SCALAR, MPI_SUM, comm));
170   //  Restore Vectors
171   PetscCall(VecRestoreArrayRead(G_loc, &g));
172 
173   PetscFunctionReturn(0);
174 }
175 
176 // Implicit time-stepper function setup
177 PetscErrorCode IFunction_NS(TS ts, PetscReal t, Vec Q, Vec Q_dot, Vec G, void *user_data) {
178   User         user = *(User *)user_data;
179   PetscScalar  dt;
180   Vec          Q_loc = user->Q_loc, Q_dot_loc = user->Q_dot_loc, G_loc;
181   PetscMemType q_mem_type, q_dot_mem_type, g_mem_type;
182   PetscFunctionBeginUser;
183 
184   // Get local vectors
185   PetscCall(DMGetNamedLocalVector(user->dm, "ResidualLocal", &G_loc));
186 
187   // Update time dependent data
188   PetscCall(UpdateBoundaryValues(user, Q_loc, t));
189   PetscCall(UpdateContextLabel(&user->time, t, user->op_ifunction, user->phys->solution_time_label));
190   PetscCall(TSGetTimeStep(ts, &dt));
191   PetscCall(UpdateContextLabel(&user->dt, dt, user->op_ifunction, user->phys->timestep_size_label));
192 
193   // Global-to-local
194   PetscCall(DMGlobalToLocalBegin(user->dm, Q, INSERT_VALUES, Q_loc));
195   PetscCall(DMGlobalToLocalBegin(user->dm, Q_dot, INSERT_VALUES, Q_dot_loc));
196   PetscCall(DMGlobalToLocalEnd(user->dm, Q, INSERT_VALUES, Q_loc));
197   PetscCall(DMGlobalToLocalEnd(user->dm, Q_dot, INSERT_VALUES, Q_dot_loc));
198 
199   // Place PETSc vectors in CEED vectors
200   PetscCall(VecReadP2C(Q_loc, &q_mem_type, user->q_ceed));
201   PetscCall(VecReadP2C(Q_dot_loc, &q_dot_mem_type, user->q_dot_ceed));
202   PetscCall(VecP2C(G_loc, &g_mem_type, user->g_ceed));
203 
204   // Apply CEED operator
205   CeedOperatorApply(user->op_ifunction, user->q_ceed, user->g_ceed, CEED_REQUEST_IMMEDIATE);
206 
207   // Restore vectors
208   PetscCall(VecReadC2P(user->q_ceed, q_mem_type, Q_loc));
209   PetscCall(VecReadC2P(user->q_dot_ceed, q_dot_mem_type, Q_dot_loc));
210   PetscCall(VecC2P(user->g_ceed, g_mem_type, G_loc));
211 
212   // Local-to-Global
213   PetscCall(VecZeroEntries(G));
214   PetscCall(DMLocalToGlobal(user->dm, G_loc, ADD_VALUES, G));
215 
216   // Restore vectors
217   PetscCall(DMRestoreNamedLocalVector(user->dm, "ResidualLocal", &G_loc));
218 
219   PetscFunctionReturn(0);
220 }
221 
222 static PetscErrorCode MatMult_NS_IJacobian(Mat J, Vec Q, Vec G) {
223   User               user;
224   const PetscScalar *q;
225   PetscScalar       *g;
226   PetscMemType       q_mem_type, g_mem_type;
227   PetscFunctionBeginUser;
228   PetscCall(MatShellGetContext(J, &user));
229   Vec Q_loc = user->Q_dot_loc,  // Note - Q_dot_loc has zero BCs
230       G_loc;
231 
232   // Get local vectors
233   PetscCall(DMGetLocalVector(user->dm, &G_loc));
234 
235   // Global-to-local
236   PetscCall(DMGlobalToLocal(user->dm, Q, INSERT_VALUES, Q_loc));
237 
238   // Place PETSc vectors in CEED vectors
239   PetscCall(VecGetArrayReadAndMemType(Q_loc, &q, &q_mem_type));
240   PetscCall(VecGetArrayAndMemType(G_loc, &g, &g_mem_type));
241   CeedVectorSetArray(user->q_ceed, MemTypeP2C(q_mem_type), CEED_USE_POINTER, (PetscScalar *)q);
242   CeedVectorSetArray(user->g_ceed, MemTypeP2C(g_mem_type), CEED_USE_POINTER, g);
243 
244   // Apply CEED operator
245   CeedOperatorApply(user->op_ijacobian, user->q_ceed, user->g_ceed, CEED_REQUEST_IMMEDIATE);
246 
247   // Restore vectors
248   CeedVectorTakeArray(user->q_ceed, MemTypeP2C(q_mem_type), NULL);
249   CeedVectorTakeArray(user->g_ceed, MemTypeP2C(g_mem_type), NULL);
250   PetscCall(VecRestoreArrayReadAndMemType(Q_loc, &q));
251   PetscCall(VecRestoreArrayAndMemType(G_loc, &g));
252 
253   // Local-to-Global
254   PetscCall(VecZeroEntries(G));
255   PetscCall(DMLocalToGlobal(user->dm, G_loc, ADD_VALUES, G));
256 
257   // Restore vectors
258   PetscCall(DMRestoreLocalVector(user->dm, &G_loc));
259   PetscFunctionReturn(0);
260 }
261 
262 PetscErrorCode MatGetDiagonal_NS_IJacobian(Mat A, Vec D) {
263   User         user;
264   Vec          D_loc;
265   PetscScalar *d;
266   PetscMemType mem_type;
267 
268   PetscFunctionBeginUser;
269   MatShellGetContext(A, &user);
270   PetscCall(DMGetLocalVector(user->dm, &D_loc));
271   PetscCall(VecGetArrayAndMemType(D_loc, &d, &mem_type));
272   CeedVectorSetArray(user->g_ceed, MemTypeP2C(mem_type), CEED_USE_POINTER, d);
273   CeedOperatorLinearAssembleDiagonal(user->op_ijacobian, user->g_ceed, CEED_REQUEST_IMMEDIATE);
274   CeedVectorTakeArray(user->g_ceed, MemTypeP2C(mem_type), NULL);
275   PetscCall(VecRestoreArrayAndMemType(D_loc, &d));
276   PetscCall(VecZeroEntries(D));
277   PetscCall(DMLocalToGlobal(user->dm, D_loc, ADD_VALUES, D));
278   PetscCall(DMRestoreLocalVector(user->dm, &D_loc));
279   VecViewFromOptions(D, NULL, "-diag_vec_view");
280   PetscFunctionReturn(0);
281 }
282 
283 static PetscErrorCode FormPreallocation(User user, PetscBool pbdiagonal, Mat J, CeedVector *coo_values) {
284   PetscCount ncoo;
285   PetscInt  *rows, *cols;
286 
287   PetscFunctionBeginUser;
288   if (pbdiagonal) {
289     CeedSize l_size;
290     CeedOperatorGetActiveVectorLengths(user->op_ijacobian, &l_size, NULL);
291     ncoo = l_size * 5;
292     rows = malloc(ncoo * sizeof(rows[0]));
293     cols = malloc(ncoo * sizeof(cols[0]));
294     for (PetscCount n = 0; n < l_size / 5; n++) {
295       for (PetscInt i = 0; i < 5; i++) {
296         for (PetscInt j = 0; j < 5; j++) {
297           rows[(n * 5 + i) * 5 + j] = n * 5 + i;
298           cols[(n * 5 + i) * 5 + j] = n * 5 + j;
299         }
300       }
301     }
302   } else {
303     PetscCall(CeedOperatorLinearAssembleSymbolic(user->op_ijacobian, &ncoo, &rows, &cols));
304   }
305   PetscCall(MatSetPreallocationCOOLocal(J, ncoo, rows, cols));
306   free(rows);
307   free(cols);
308   CeedVectorCreate(user->ceed, ncoo, coo_values);
309   PetscFunctionReturn(0);
310 }
311 
312 static PetscErrorCode FormSetValues(User user, PetscBool pbdiagonal, Mat J, CeedVector coo_values) {
313   CeedMemType        mem_type = CEED_MEM_HOST;
314   const PetscScalar *values;
315   MatType            mat_type;
316 
317   PetscFunctionBeginUser;
318   PetscCall(MatGetType(J, &mat_type));
319   if (strstr(mat_type, "kokkos") || strstr(mat_type, "cusparse")) mem_type = CEED_MEM_DEVICE;
320   if (user->app_ctx->pmat_pbdiagonal) {
321     CeedOperatorLinearAssemblePointBlockDiagonal(user->op_ijacobian, coo_values, CEED_REQUEST_IMMEDIATE);
322   } else {
323     CeedOperatorLinearAssemble(user->op_ijacobian, coo_values);
324   }
325   CeedVectorGetArrayRead(coo_values, mem_type, &values);
326   PetscCall(MatSetValuesCOO(J, values, INSERT_VALUES));
327   CeedVectorRestoreArrayRead(coo_values, &values);
328   PetscFunctionReturn(0);
329 }
330 
331 PetscErrorCode FormIJacobian_NS(TS ts, PetscReal t, Vec Q, Vec Q_dot, PetscReal shift, Mat J, Mat J_pre, void *user_data) {
332   User      user = *(User *)user_data;
333   PetscBool J_is_shell, J_is_mffd, J_pre_is_shell;
334   PetscFunctionBeginUser;
335   if (user->phys->ijacobian_time_shift_label) CeedOperatorContextSetDouble(user->op_ijacobian, user->phys->ijacobian_time_shift_label, &shift);
336   PetscCall(PetscObjectTypeCompare((PetscObject)J, MATMFFD, &J_is_mffd));
337   PetscCall(PetscObjectTypeCompare((PetscObject)J, MATSHELL, &J_is_shell));
338   PetscCall(PetscObjectTypeCompare((PetscObject)J_pre, MATSHELL, &J_pre_is_shell));
339   if (!user->matrices_set_up) {
340     if (J_is_shell) {
341       PetscCall(MatShellSetContext(J, user));
342       PetscCall(MatShellSetOperation(J, MATOP_MULT, (void (*)(void))MatMult_NS_IJacobian));
343       PetscCall(MatShellSetOperation(J, MATOP_GET_DIAGONAL, (void (*)(void))MatGetDiagonal_NS_IJacobian));
344       PetscCall(MatSetUp(J));
345     }
346     if (!J_pre_is_shell) {
347       PetscCall(FormPreallocation(user, user->app_ctx->pmat_pbdiagonal, J_pre, &user->coo_values_pmat));
348     }
349     if (J != J_pre && !J_is_shell && !J_is_mffd) {
350       PetscCall(FormPreallocation(user, PETSC_FALSE, J, &user->coo_values_amat));
351     }
352     user->matrices_set_up = true;
353   }
354   if (!J_pre_is_shell) {
355     PetscCall(FormSetValues(user, user->app_ctx->pmat_pbdiagonal, J_pre, user->coo_values_pmat));
356   }
357   if (user->coo_values_amat) {
358     PetscCall(FormSetValues(user, PETSC_FALSE, J, user->coo_values_amat));
359   } else if (J_is_mffd) {
360     PetscCall(MatAssemblyBegin(J, MAT_FINAL_ASSEMBLY));
361     PetscCall(MatAssemblyEnd(J, MAT_FINAL_ASSEMBLY));
362   }
363   PetscFunctionReturn(0);
364 }
365 
366 PetscErrorCode WriteOutput(User user, Vec Q, PetscInt step_no, PetscScalar time) {
367   Vec         Q_loc;
368   char        file_path[PETSC_MAX_PATH_LEN];
369   PetscViewer viewer;
370   PetscFunctionBeginUser;
371 
372   if (user->app_ctx->checkpoint_vtk) {
373     // Set up output
374     PetscCall(DMGetLocalVector(user->dm, &Q_loc));
375     PetscCall(PetscObjectSetName((PetscObject)Q_loc, "StateVec"));
376     PetscCall(VecZeroEntries(Q_loc));
377     PetscCall(DMGlobalToLocal(user->dm, Q, INSERT_VALUES, Q_loc));
378 
379     // Output
380     PetscCall(PetscSNPrintf(file_path, sizeof file_path, "%s/ns-%03" PetscInt_FMT ".vtu", user->app_ctx->output_dir, step_no));
381 
382     PetscCall(PetscViewerVTKOpen(PetscObjectComm((PetscObject)Q), file_path, FILE_MODE_WRITE, &viewer));
383     PetscCall(VecView(Q_loc, viewer));
384     PetscCall(PetscViewerDestroy(&viewer));
385     if (user->dm_viz) {
386       Vec         Q_refined, Q_refined_loc;
387       char        file_path_refined[PETSC_MAX_PATH_LEN];
388       PetscViewer viewer_refined;
389 
390       PetscCall(DMGetGlobalVector(user->dm_viz, &Q_refined));
391       PetscCall(DMGetLocalVector(user->dm_viz, &Q_refined_loc));
392       PetscCall(PetscObjectSetName((PetscObject)Q_refined_loc, "Refined"));
393 
394       PetscCall(MatInterpolate(user->interp_viz, Q, Q_refined));
395       PetscCall(VecZeroEntries(Q_refined_loc));
396       PetscCall(DMGlobalToLocal(user->dm_viz, Q_refined, INSERT_VALUES, Q_refined_loc));
397 
398       PetscCall(
399           PetscSNPrintf(file_path_refined, sizeof file_path_refined, "%s/nsrefined-%03" PetscInt_FMT ".vtu", user->app_ctx->output_dir, step_no));
400 
401       PetscCall(PetscViewerVTKOpen(PetscObjectComm((PetscObject)Q_refined), file_path_refined, FILE_MODE_WRITE, &viewer_refined));
402       PetscCall(VecView(Q_refined_loc, viewer_refined));
403       PetscCall(DMRestoreLocalVector(user->dm_viz, &Q_refined_loc));
404       PetscCall(DMRestoreGlobalVector(user->dm_viz, &Q_refined));
405       PetscCall(PetscViewerDestroy(&viewer_refined));
406     }
407     PetscCall(DMRestoreLocalVector(user->dm, &Q_loc));
408   }
409 
410   // Save data in a binary file for continuation of simulations
411   if (user->app_ctx->add_stepnum2bin) {
412     PetscCall(PetscSNPrintf(file_path, sizeof file_path, "%s/ns-solution-%" PetscInt_FMT ".bin", user->app_ctx->output_dir, step_no));
413   } else {
414     PetscCall(PetscSNPrintf(file_path, sizeof file_path, "%s/ns-solution.bin", user->app_ctx->output_dir));
415   }
416   PetscCall(PetscViewerBinaryOpen(user->comm, file_path, FILE_MODE_WRITE, &viewer));
417 
418   PetscInt token = FLUIDS_FILE_TOKEN;
419   PetscCall(PetscViewerBinaryWrite(viewer, &token, 1, PETSC_INT));
420   PetscCall(PetscViewerBinaryWrite(viewer, &step_no, 1, PETSC_INT));
421   time /= user->units->second;  // Dimensionalize time back
422   PetscCall(PetscViewerBinaryWrite(viewer, &time, 1, PETSC_REAL));
423   PetscCall(VecView(Q, viewer));
424   PetscCall(PetscViewerDestroy(&viewer));
425   PetscFunctionReturn(0);
426 }
427 
428 // CSV Monitor
429 PetscErrorCode TSMonitor_WallForce(TS ts, PetscInt step_no, PetscReal time, Vec Q, void *ctx) {
430   User              user = ctx;
431   Vec               G_loc;
432   PetscInt          num_wall = user->app_ctx->wall_forces.num_wall, dim = 3;
433   const PetscInt   *walls  = user->app_ctx->wall_forces.walls;
434   PetscViewer       viewer = user->app_ctx->wall_forces.viewer;
435   PetscViewerFormat format = user->app_ctx->wall_forces.viewer_format;
436   PetscScalar      *reaction_force;
437   PetscBool         iascii;
438 
439   PetscFunctionBeginUser;
440   if (!viewer) PetscFunctionReturn(0);
441   PetscCall(DMGetNamedLocalVector(user->dm, "ResidualLocal", &G_loc));
442   PetscCall(PetscMalloc1(num_wall * dim, &reaction_force));
443   PetscCall(Surface_Forces_NS(user->dm, G_loc, num_wall, walls, reaction_force));
444   PetscCall(DMRestoreNamedLocalVector(user->dm, "ResidualLocal", &G_loc));
445 
446   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
447 
448   if (iascii) {
449     if (format == PETSC_VIEWER_ASCII_CSV && !user->app_ctx->wall_forces.header_written) {
450       PetscCall(PetscViewerASCIIPrintf(viewer, "Step,Time,Wall,ForceX,ForceY,ForceZ\n"));
451       user->app_ctx->wall_forces.header_written = PETSC_TRUE;
452     }
453     for (PetscInt w = 0; w < num_wall; w++) {
454       PetscInt wall = walls[w];
455       if (format == PETSC_VIEWER_ASCII_CSV) {
456         PetscCall(PetscViewerASCIIPrintf(viewer, "%" PetscInt_FMT ",%g,%" PetscInt_FMT ",%g,%g,%g\n", step_no, time, wall,
457                                          reaction_force[w * dim + 0], reaction_force[w * dim + 1], reaction_force[w * dim + 2]));
458 
459       } else {
460         PetscCall(PetscViewerASCIIPrintf(viewer, "Wall %" PetscInt_FMT " Forces: Force_x = %12g, Force_y = %12g, Force_z = %12g\n", wall,
461                                          reaction_force[w * dim + 0], reaction_force[w * dim + 1], reaction_force[w * dim + 2]));
462       }
463     }
464   }
465   PetscCall(PetscFree(reaction_force));
466   PetscFunctionReturn(0);
467 }
468 
469 // User provided TS Monitor
470 PetscErrorCode TSMonitor_NS(TS ts, PetscInt step_no, PetscReal time, Vec Q, void *ctx) {
471   User user = ctx;
472   PetscFunctionBeginUser;
473 
474   // Print every 'checkpoint_interval' steps
475   if (user->app_ctx->checkpoint_interval <= 0 || step_no % user->app_ctx->checkpoint_interval != 0 ||
476       (user->app_ctx->cont_steps == step_no && step_no != 0))
477     PetscFunctionReturn(0);
478 
479   PetscCall(WriteOutput(user, Q, step_no, time));
480 
481   PetscFunctionReturn(0);
482 }
483 
484 // TS: Create, setup, and solve
485 PetscErrorCode TSSolve_NS(DM dm, User user, AppCtx app_ctx, Physics phys, Vec *Q, PetscScalar *f_time, TS *ts) {
486   MPI_Comm    comm = user->comm;
487   TSAdapt     adapt;
488   PetscScalar final_time;
489   PetscFunctionBeginUser;
490 
491   PetscCall(TSCreate(comm, ts));
492   PetscCall(TSSetDM(*ts, dm));
493   if (phys->implicit) {
494     PetscCall(TSSetType(*ts, TSBDF));
495     if (user->op_ifunction) {
496       PetscCall(TSSetIFunction(*ts, NULL, IFunction_NS, &user));
497     } else {  // Implicit integrators can fall back to using an RHSFunction
498       PetscCall(TSSetRHSFunction(*ts, NULL, RHS_NS, &user));
499     }
500     if (user->op_ijacobian) {
501       PetscCall(DMTSSetIJacobian(dm, FormIJacobian_NS, &user));
502       if (app_ctx->amat_type) {
503         Mat Pmat, Amat;
504         PetscCall(DMCreateMatrix(dm, &Pmat));
505         PetscCall(DMSetMatType(dm, app_ctx->amat_type));
506         PetscCall(DMCreateMatrix(dm, &Amat));
507         PetscCall(TSSetIJacobian(*ts, Amat, Pmat, NULL, NULL));
508         PetscCall(MatDestroy(&Amat));
509         PetscCall(MatDestroy(&Pmat));
510       }
511     }
512   } else {
513     if (!user->op_rhs) SETERRQ(comm, PETSC_ERR_ARG_NULL, "Problem does not provide RHSFunction");
514     PetscCall(TSSetType(*ts, TSRK));
515     PetscCall(TSRKSetType(*ts, TSRK5F));
516     PetscCall(TSSetRHSFunction(*ts, NULL, RHS_NS, &user));
517   }
518   PetscCall(TSSetMaxTime(*ts, 500. * user->units->second));
519   PetscCall(TSSetExactFinalTime(*ts, TS_EXACTFINALTIME_STEPOVER));
520   PetscCall(TSSetErrorIfStepFails(*ts, PETSC_FALSE));
521   PetscCall(TSSetTimeStep(*ts, 1.e-2 * user->units->second));
522   if (app_ctx->test_type != TESTTYPE_NONE) {
523     PetscCall(TSSetMaxSteps(*ts, 10));
524   }
525   PetscCall(TSGetAdapt(*ts, &adapt));
526   PetscCall(TSAdaptSetStepLimits(adapt, 1.e-12 * user->units->second, 1.e2 * user->units->second));
527   PetscCall(TSSetFromOptions(*ts));
528   user->time = user->time_bc_set = -1.0;  // require all BCs and ctx to be updated
529   user->dt                       = -1.0;
530   if (!app_ctx->cont_steps) {  // print initial condition
531     if (app_ctx->test_type == TESTTYPE_NONE) {
532       PetscCall(TSMonitor_NS(*ts, 0, 0., *Q, user));
533     }
534   } else {  // continue from time of last output
535     PetscInt    count;
536     PetscViewer viewer;
537 
538     if (app_ctx->cont_time <= 0) {  // Legacy files did not include step number and time
539       PetscCall(PetscViewerBinaryOpen(comm, app_ctx->cont_time_file, FILE_MODE_READ, &viewer));
540       PetscCall(PetscViewerBinaryRead(viewer, &app_ctx->cont_time, 1, &count, PETSC_REAL));
541       PetscCall(PetscViewerDestroy(&viewer));
542       PetscCheck(app_ctx->cont_steps != -1, comm, PETSC_ERR_ARG_INCOMP,
543                  "-continue step number not specified, but checkpoint file does not contain a step number (likely written by older code version)");
544     }
545     PetscCall(TSSetTime(*ts, app_ctx->cont_time * user->units->second));
546     PetscCall(TSSetStepNumber(*ts, app_ctx->cont_steps));
547   }
548   if (app_ctx->test_type == TESTTYPE_NONE) {
549     PetscCall(TSMonitorSet(*ts, TSMonitor_NS, user, NULL));
550   }
551   if (app_ctx->wall_forces.viewer) {
552     PetscCall(TSMonitorSet(*ts, TSMonitor_WallForce, user, NULL));
553   }
554   if (app_ctx->turb_spanstats_enable) {
555     PetscCall(TSMonitorSet(*ts, TSMonitor_Statistics, user, NULL));
556     CeedScalar previous_time = app_ctx->cont_time * user->units->second;
557     CeedOperatorContextSetDouble(user->spanstats.op_stats_collect, user->spanstats.previous_time_label, &previous_time);
558   }
559 
560   // Solve
561   PetscReal start_time;
562   PetscInt  start_step;
563   PetscCall(TSGetTime(*ts, &start_time));
564   PetscCall(TSGetStepNumber(*ts, &start_step));
565 
566   PetscPreLoadBegin(PETSC_FALSE, "Fluids Solve");
567   PetscCall(TSSetTime(*ts, start_time));
568   PetscCall(TSSetStepNumber(*ts, start_step));
569   if (PetscPreLoadingOn) {
570     // LCOV_EXCL_START
571     SNES      snes;
572     Vec       Q_preload;
573     PetscReal rtol;
574     PetscCall(VecDuplicate(*Q, &Q_preload));
575     PetscCall(VecCopy(*Q, Q_preload));
576     PetscCall(TSGetSNES(*ts, &snes));
577     PetscCall(SNESGetTolerances(snes, NULL, &rtol, NULL, NULL, NULL));
578     PetscCall(SNESSetTolerances(snes, PETSC_DEFAULT, .99, PETSC_DEFAULT, PETSC_DEFAULT, PETSC_DEFAULT));
579     PetscCall(TSSetSolution(*ts, *Q));
580     PetscCall(TSStep(*ts));
581     PetscCall(SNESSetTolerances(snes, PETSC_DEFAULT, rtol, PETSC_DEFAULT, PETSC_DEFAULT, PETSC_DEFAULT));
582     PetscCall(VecDestroy(&Q_preload));
583     // LCOV_EXCL_STOP
584   } else {
585     PetscCall(PetscBarrier((PetscObject)*ts));
586     PetscCall(TSSolve(*ts, *Q));
587   }
588   PetscPreLoadEnd();
589 
590   PetscCall(TSGetSolveTime(*ts, &final_time));
591   *f_time = final_time;
592 
593   if (app_ctx->test_type == TESTTYPE_NONE) {
594     PetscInt step_no;
595     PetscCall(TSGetStepNumber(*ts, &step_no));
596     if (user->app_ctx->checkpoint_interval > 0 || user->app_ctx->checkpoint_interval == -1) {
597       PetscCall(WriteOutput(user, *Q, step_no, final_time));
598     }
599 
600     PetscLogEvent stage_id;
601     PetscStageLog stage_log;
602 
603     PetscCall(PetscLogStageGetId("Fluids Solve", &stage_id));
604     PetscCall(PetscLogGetStageLog(&stage_log));
605     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Time taken for solution (sec): %g\n", stage_log->stageInfo[stage_id].perfInfo.time));
606   }
607   PetscFunctionReturn(0);
608 }
609