xref: /honee/qfunctions/advection.h (revision 5239d4bba5deb4ba49de060139a401cb5a83cb5a)
1 // SPDX-FileCopyrightText: Copyright (c) 2017-2024, HONEE contributors.
2 // SPDX-License-Identifier: Apache-2.0 OR BSD-2-Clause
3 
4 /// @file
5 /// Advection initial condition and operator for Navier-Stokes example using PETSc
6 #include <ceed.h>
7 #include <math.h>
8 
9 #include "advection_types.h"
10 #include "newtonian_state.h"
11 #include "newtonian_types.h"
12 #include "stabilization_types.h"
13 #include "utils.h"
14 
15 // *****************************************************************************
16 // This QFunction sets the initial conditions and the boundary conditions
17 //   for two test cases: ROTATION and TRANSLATION
18 //
19 // -- ROTATION (default)
20 //      Initial Conditions:
21 //        Mass Density:
22 //          Constant mass density of 1.0
23 //        Momentum Density:
24 //          Rotational field in x,y
25 //        Energy Density:
26 //          Maximum of 1. x0 decreasing linearly to 0. as radial distance
27 //            increases to (1.-r/rc), then 0. everywhere else
28 //
29 //      Boundary Conditions:
30 //        Mass Density:
31 //          0.0 flux
32 //        Momentum Density:
33 //          0.0
34 //        Energy Density:
35 //          0.0 flux
36 //
37 // -- TRANSLATION
38 //      Initial Conditions:
39 //        Mass Density:
40 //          Constant mass density of 1.0
41 //        Momentum Density:
42 //           Constant rectilinear field in x,y
43 //        Energy Density:
44 //          Maximum of 1. x0 decreasing linearly to 0. as radial distance
45 //            increases to (1.-r/rc), then 0. everywhere else
46 //
47 //      Boundary Conditions:
48 //        Mass Density:
49 //          0.0 flux
50 //        Momentum Density:
51 //          0.0
52 //        Energy Density:
53 //          Inflow BCs:
54 //            E = E_wind
55 //          Outflow BCs:
56 //            E = E(boundary)
57 //          Both In/Outflow BCs for E are applied weakly in the
58 //            QFunction "Advection2d_Sur"
59 //
60 // *****************************************************************************
61 
62 // *****************************************************************************
63 // This helper function provides the exact, time-dependent solution and IC formulation for 2D advection
64 // *****************************************************************************
65 CEED_QFUNCTION_HELPER int Exact_AdvectionGeneric(CeedInt dim, CeedScalar time, const CeedScalar X[], CeedInt Nf, CeedScalar q[], void *ctx) {
66   const SetupContextAdv context = (SetupContextAdv)ctx;
67   const CeedScalar      rc      = context->rc;
68   const CeedScalar      lx      = context->lx;
69   const CeedScalar      ly      = context->ly;
70   const CeedScalar      lz      = dim == 2 ? 0. : context->lz;
71   const CeedScalar     *wind    = context->wind;
72 
73   const CeedScalar center[3] = {0.5 * lx, 0.5 * ly, 0.5 * lz};
74   const CeedScalar theta     = dim == 2 ? M_PI / 3 : M_PI;
75   const CeedScalar x0[3]     = {center[0] + .25 * lx * cos(theta + time), center[1] + .25 * ly * sin(theta + time), 0.5 * lz};
76 
77   const CeedScalar x = X[0], y = X[1], z = dim == 2 ? 0. : X[2];
78 
79   switch (context->wind_type) {
80     case ADVDIF_WIND_ROTATION:
81       q[0] = 1.;
82       q[1] = -(y - center[1]);
83       q[2] = (x - center[0]);
84       q[3] = 0;
85       break;
86     case ADVDIF_WIND_TRANSLATION:
87       q[0] = 1.;
88       q[1] = wind[0];
89       q[2] = wind[1];
90       q[3] = dim == 2 ? 0. : wind[2];
91       break;
92     case ADVDIF_WIND_BOUNDARY_LAYER:
93       q[0] = 1.;
94       q[1] = y / ly;
95       q[2] = 0.;
96       q[3] = 0.;
97       break;
98   }
99 
100   switch (context->initial_condition_type) {
101     case ADVDIF_IC_BUBBLE_SPHERE:
102     case ADVDIF_IC_BUBBLE_CYLINDER: {
103       CeedScalar r = sqrt(Square(x - x0[0]) + Square(y - x0[1]) + Square(z - x0[2]));
104 
105       switch (context->bubble_continuity_type) {
106         // original continuous, smooth shape
107         case ADVDIF_BUBBLE_CONTINUITY_SMOOTH:
108           q[4] = r <= rc ? (1. - r / rc) : 0.;
109           break;
110         // discontinuous, sharp back half shape
111         case ADVDIF_BUBBLE_CONTINUITY_BACK_SHARP:
112           q[4] = ((r <= rc) && (y < center[1])) ? (1. - r / rc) : 0.;
113           break;
114         // attempt to define a finite thickness that will get resolved under grid refinement
115         case ADVDIF_BUBBLE_CONTINUITY_THICK:
116           q[4] = ((r <= rc) && (y < center[1])) ? (1. - r / rc) * fmin(1.0, (center[1] - y) / 1.25) : 0.;
117           break;
118         case ADVDIF_BUBBLE_CONTINUITY_COSINE:
119           q[4] = r <= rc ? .5 + .5 * cos(r * M_PI / rc) : 0;
120           break;
121       }
122       break;
123     }
124 
125     case ADVDIF_IC_COSINE_HILL: {
126       CeedScalar r          = sqrt(Square(x - center[0]) + Square(y - center[1]));
127       CeedScalar half_width = context->lx / 2;
128       q[4]                  = r > half_width ? 0. : cos(2 * M_PI * r / half_width + M_PI) + 1.;
129     } break;
130 
131     case ADVDIF_IC_SKEW: {
132       CeedScalar       skewed_barrier[3]  = {wind[0], wind[1], 0};
133       CeedScalar       inflow_to_point[3] = {x - context->lx / 2, y, 0};
134       CeedScalar       cross_product[3]   = {0};
135       const CeedScalar boundary_threshold = 20 * CEED_EPSILON;
136       Cross3(skewed_barrier, inflow_to_point, cross_product);
137 
138       q[4] = cross_product[2] > boundary_threshold ? 0 : 1;
139       if ((x < boundary_threshold && wind[0] < boundary_threshold) ||                // outflow at -x boundary
140           (y < boundary_threshold && wind[1] < boundary_threshold) ||                // outflow at -y boundary
141           (x > context->lx - boundary_threshold && wind[0] > boundary_threshold) ||  // outflow at +x boundary
142           (y > context->ly - boundary_threshold && wind[1] > boundary_threshold)     // outflow at +y boundary
143       ) {
144         q[4] = 0;
145       }
146     } break;
147 
148     case ADVDIF_IC_WAVE: {
149       CeedScalar theta = context->wave_frequency * DotN(X, wind, dim) + context->wave_phase;
150       switch (context->wave_type) {
151         case ADVDIF_WAVE_SINE:
152           q[4] = sin(theta);
153           break;
154         case ADVDIF_WAVE_SQUARE:
155           q[4] = sin(theta) > 100 * CEED_EPSILON ? 1 : -1;
156           break;
157       }
158     } break;
159     case ADVDIF_IC_BOUNDARY_LAYER: {
160       const CeedScalar boundary_threshold = 20 * CEED_EPSILON;
161 
162       if ((x < boundary_threshold) || (y > ly - boundary_threshold)) {
163         q[4] = 1;  // inflow and top boundary
164       } else if (y < boundary_threshold) {
165         q[4] = 0;  // lower wall
166       } else {
167         q[4] = y / ly;  // interior and outflow boundary
168       }
169     } break;
170   }
171   return 0;
172 }
173 
174 // *****************************************************************************
175 // This QFunction sets the initial conditions for 3D advection
176 // *****************************************************************************
177 CEED_QFUNCTION(ICsAdvection)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
178   const CeedScalar(*X)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[0];
179   CeedScalar(*q0)[CEED_Q_VLA]      = (CeedScalar(*)[CEED_Q_VLA])out[0];
180 
181   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
182     const CeedScalar x[]  = {X[0][i], X[1][i], X[2][i]};
183     CeedScalar       q[5] = {0.};
184 
185     Exact_AdvectionGeneric(3, 0., x, 5, q, ctx);
186     for (CeedInt j = 0; j < 5; j++) q0[j][i] = q[j];
187   }
188   return 0;
189 }
190 
191 // *****************************************************************************
192 // This QFunction sets the initial conditions for 2D advection
193 // *****************************************************************************
194 CEED_QFUNCTION(ICsAdvection2d)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
195   const CeedScalar(*X)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[0];
196   CeedScalar(*q0)[CEED_Q_VLA]      = (CeedScalar(*)[CEED_Q_VLA])out[0];
197   const SetupContextAdv context    = (SetupContextAdv)ctx;
198 
199   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
200     const CeedScalar x[]  = {X[0][i], X[1][i]};
201     CeedScalar       q[5] = {0.};
202 
203     Exact_AdvectionGeneric(2, context->time, x, 5, q, ctx);
204     for (CeedInt j = 0; j < 5; j++) q0[j][i] = q[j];
205   }
206   return 0;
207 }
208 
209 CEED_QFUNCTION_HELPER void StatePhysicalGradientFromReference_ND(CeedInt N, CeedInt Q, CeedInt i, NewtonianIdealGasContext gas, State s,
210                                                                  StateVariable state_var, const CeedScalar *grad_q, const CeedScalar *dXdx,
211                                                                  State *grad_s) {
212   switch (N) {
213     case 2: {
214       for (CeedInt k = 0; k < 2; k++) {
215         CeedScalar dqi[5];
216         for (CeedInt j = 0; j < 5; j++) {
217           dqi[j] = grad_q[(Q * 5) * 0 + Q * j + i] * dXdx[0 * N + k] + grad_q[(Q * 5) * 1 + Q * j + i] * dXdx[1 * N + k];
218         }
219         grad_s[k] = StateFromQ_fwd(gas, s, dqi, state_var);
220       }
221       CeedScalar U[5] = {0.};
222       grad_s[2]       = StateFromU(gas, U);
223     } break;
224     case 3:
225       // Cannot directly use StatePhysicalGradientFromReference helper functions due to SYCL online compiler incompatabilities
226       for (CeedInt k = 0; k < 3; k++) {
227         CeedScalar dqi[5];
228         for (CeedInt j = 0; j < 5; j++) {
229           dqi[j] = grad_q[(Q * 5) * 0 + Q * j + i] * dXdx[0 * N + k] + grad_q[(Q * 5) * 1 + Q * j + i] * dXdx[1 * N + k] +
230                    grad_q[(Q * 5) * 2 + Q * j + i] * dXdx[2 * N + k];
231         }
232         grad_s[k] = StateFromQ_fwd(gas, s, dqi, state_var);
233       }
234       break;
235   }
236 }
237 
238 // @brief Calculate the stabilization constant \tau
239 CEED_QFUNCTION_HELPER CeedScalar Tau(AdvectionContext context, const State s, const CeedScalar *dXdx, CeedInt dim) {
240   switch (context->stabilization_tau) {
241     case STAB_TAU_CTAU: {
242       CeedScalar uX[3] = {0.};
243 
244       MatVecNM(dXdx, s.Y.velocity, dim, dim, CEED_NOTRANSPOSE, uX);
245       return context->CtauS / sqrt(DotN(uX, uX, dim));
246     } break;
247     case STAB_TAU_ADVDIFF_SHAKIB: {
248       CeedScalar gijd_mat[9] = {0.}, gij_uj[3] = {0.};
249 
250       MatMatN(dXdx, dXdx, dim, CEED_TRANSPOSE, CEED_NOTRANSPOSE, gijd_mat);
251       // (1/2)^2 to account for reference element size; for length 1 square/cube element, gij should be identity matrix
252       ScaleN(gijd_mat, 0.25, Square(dim));
253       MatVecNM(gijd_mat, s.Y.velocity, dim, dim, CEED_NOTRANSPOSE, gij_uj);
254       return 1 / sqrt(Square(2 * context->Ctau_t / context->dt) + DotN(s.Y.velocity, gij_uj, dim) * Square(context->Ctau_a) +
255                       Square(context->diffusion_coeff) * DotN(gijd_mat, gijd_mat, dim * dim) * Square(context->Ctau_d));
256     } break;
257     default:
258       return 0.;
259   }
260 }
261 
262 // *****************************************************************************
263 // This QFunction implements Advection for implicit time stepping method
264 // *****************************************************************************
265 CEED_QFUNCTION_HELPER int IFunction_AdvectionGeneric(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out, CeedInt dim) {
266   AdvectionContext context = (AdvectionContext)ctx;
267 
268   const CeedScalar(*q)[CEED_Q_VLA]     = (const CeedScalar(*)[CEED_Q_VLA])in[0];
269   const CeedScalar(*grad_q)            = in[1];
270   const CeedScalar(*q_dot)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[2];
271   const CeedScalar(*q_data)            = in[3];
272   const CeedScalar(*divFdiff)          = context->divFdiff_method != DIV_DIFF_FLUX_PROJ_NONE ? in[5] : NULL;
273 
274   CeedScalar(*v)[CEED_Q_VLA]         = (CeedScalar(*)[CEED_Q_VLA])out[0];
275   CeedScalar(*grad_v)[5][CEED_Q_VLA] = (CeedScalar(*)[5][CEED_Q_VLA])out[1];
276 
277   NewtonianIdealGasContext         gas;
278   struct NewtonianIdealGasContext_ gas_struct = {0};
279   gas                                         = &gas_struct;
280 
281   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
282     const CeedScalar qi[5] = {q[0][i], q[1][i], q[2][i], q[3][i], q[4][i]};
283     const State      s     = StateFromU(gas, qi);
284 
285     CeedScalar wdetJ, dXdx[9];
286     QdataUnpack_ND(dim, Q, i, q_data, &wdetJ, dXdx);
287     State grad_s[3];
288     StatePhysicalGradientFromReference_ND(dim, Q, i, gas, s, STATEVAR_CONSERVATIVE, grad_q, dXdx, grad_s);
289 
290     const CeedScalar Grad_E[3] = {grad_s[0].U.E_total, grad_s[1].U.E_total, grad_s[2].U.E_total};
291 
292     for (CeedInt f = 0; f < 4; f++) {
293       for (CeedInt j = 0; j < dim; j++) grad_v[j][f][i] = 0;  // No Change in density or momentum
294       v[f][i] = wdetJ * q_dot[f][i];                          // K Mass/transient term
295     }
296 
297     CeedScalar div_u = 0;
298     for (CeedInt j = 0; j < dim; j++) {
299       for (CeedInt k = 0; k < dim; k++) {
300         div_u += grad_s[k].Y.velocity[j];
301       }
302     }
303     CeedScalar uX[3] = {0.};
304     MatVecNM(dXdx, s.Y.velocity, dim, dim, CEED_NOTRANSPOSE, uX);
305     CeedScalar strong_conv = s.U.E_total * div_u + DotN(s.Y.velocity, Grad_E, dim);
306 
307     v[4][i] = wdetJ * q_dot[4][i];  // transient part (ALWAYS)
308     if (context->strong_form) {     // Strong Galerkin convection term: v div(E u)
309       v[4][i] += wdetJ * strong_conv;
310     } else {  // Weak Galerkin convection term: -dv \cdot (E u)
311       for (CeedInt j = 0; j < dim; j++) grad_v[j][4][i] = -wdetJ * s.U.E_total * uX[j];
312     }
313 
314     {  // Diffusion
315       CeedScalar Fe[3], Fe_dXdx[3] = {0.};
316 
317       for (CeedInt i = 0; i < dim; i++) Fe[i] = -context->diffusion_coeff * grad_s[i].U.E_total;
318       MatVecNM(dXdx, Fe, dim, dim, CEED_NOTRANSPOSE, Fe_dXdx);
319       for (CeedInt k = 0; k < dim; k++) grad_v[k][4][i] -= wdetJ * Fe_dXdx[k];
320     }
321 
322     const CeedScalar TauS = Tau(context, s, dXdx, dim);
323     for (CeedInt j = 0; j < dim; j++) {
324       switch (context->stabilization) {
325         case STAB_NONE:
326           break;
327         case STAB_SU:
328           grad_v[j][4][i] += wdetJ * TauS * uX[j] * strong_conv;
329           break;
330         case STAB_SUPG: {
331           CeedScalar divFdiff_i = context->divFdiff_method != DIV_DIFF_FLUX_PROJ_NONE ? divFdiff[i] : 0.;
332           grad_v[j][4][i] += wdetJ * TauS * uX[j] * (q_dot[4][i] + strong_conv + divFdiff_i);
333         } break;
334       }
335     }
336   }
337   return 0;
338 }
339 
340 CEED_QFUNCTION(IFunction_Advection)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
341   return IFunction_AdvectionGeneric(ctx, Q, in, out, 3);
342 }
343 
344 CEED_QFUNCTION(IFunction_Advection2d)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
345   return IFunction_AdvectionGeneric(ctx, Q, in, out, 2);
346 }
347 
348 CEED_QFUNCTION_HELPER int MassFunction_AdvectionGeneric(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out, CeedInt dim) {
349   const CeedScalar(*q_dot)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[0];
350   const CeedScalar(*q)[CEED_Q_VLA]     = (const CeedScalar(*)[CEED_Q_VLA])in[1];
351   const CeedScalar(*q_data)            = in[2];
352 
353   CeedScalar(*v)[CEED_Q_VLA]         = (CeedScalar(*)[CEED_Q_VLA])out[0];
354   CeedScalar(*grad_v)[5][CEED_Q_VLA] = (CeedScalar(*)[5][CEED_Q_VLA])out[1];
355 
356   AdvectionContext                 context    = (AdvectionContext)ctx;
357   struct NewtonianIdealGasContext_ gas_struct = {0};
358   NewtonianIdealGasContext         gas        = &gas_struct;
359 
360   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
361     const CeedScalar qi[5] = {q[0][i], q[1][i], q[2][i], q[3][i], q[4][i]};
362     const State      s     = StateFromU(gas, qi);
363     CeedScalar       wdetJ, dXdx[9];
364     QdataUnpack_ND(dim, Q, i, q_data, &wdetJ, dXdx);
365 
366     for (CeedInt f = 0; f < 4; f++) {
367       for (CeedInt j = 0; j < dim; j++) grad_v[j][f][i] = 0;  // No Change in density or momentum
368       v[f][i] = wdetJ * q_dot[f][i];                          // K Mass/transient term
369     }
370 
371     // Unstabilized mass term
372     v[4][i] = wdetJ * q_dot[4][i];
373 
374     // Stabilized mass term
375     CeedScalar uX[3] = {0.};
376     MatVecNM(dXdx, s.Y.velocity, dim, dim, CEED_NOTRANSPOSE, uX);
377     const CeedScalar TauS = Tau(context, s, dXdx, dim);
378     for (CeedInt j = 0; j < dim; j++) {
379       switch (context->stabilization) {
380         case STAB_NONE:
381         case STAB_SU:
382           grad_v[j][4][i] = 0;
383           break;  // These should be run with the unstabilized mass matrix anyways
384         case STAB_SUPG:
385           grad_v[j][4][i] = wdetJ * TauS * q_dot[4][i] * uX[j];
386           break;
387       }
388     }
389   }
390   return 0;
391 }
392 
393 CEED_QFUNCTION(MassFunction_Advection)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
394   return MassFunction_AdvectionGeneric(ctx, Q, in, out, 3);
395 }
396 
397 CEED_QFUNCTION(MassFunction_Advection2D)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
398   return MassFunction_AdvectionGeneric(ctx, Q, in, out, 2);
399 }
400 
401 // *****************************************************************************
402 // This QFunction implements Advection for explicit time stepping method
403 // *****************************************************************************
404 CEED_QFUNCTION_HELPER int RHSFunction_AdvectionGeneric(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out, CeedInt dim) {
405   AdvectionContext context = (AdvectionContext)ctx;
406 
407   const CeedScalar(*q)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[0];
408   const CeedScalar(*grad_q)        = in[1];
409   const CeedScalar(*q_data)        = in[2];
410   const CeedScalar(*divFdiff)      = context->divFdiff_method != DIV_DIFF_FLUX_PROJ_NONE ? in[4] : NULL;
411 
412   CeedScalar(*v)[CEED_Q_VLA]         = (CeedScalar(*)[CEED_Q_VLA])out[0];
413   CeedScalar(*grad_v)[5][CEED_Q_VLA] = (CeedScalar(*)[5][CEED_Q_VLA])out[1];
414 
415   struct NewtonianIdealGasContext_ gas_struct = {0};
416   NewtonianIdealGasContext         gas        = &gas_struct;
417 
418   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
419     const CeedScalar qi[5] = {q[0][i], q[1][i], q[2][i], q[3][i], q[4][i]};
420     const State      s     = StateFromU(gas, qi);
421 
422     CeedScalar wdetJ, dXdx[9];
423     QdataUnpack_ND(dim, Q, i, q_data, &wdetJ, dXdx);
424     State grad_s[3];
425     StatePhysicalGradientFromReference_ND(dim, Q, i, gas, s, STATEVAR_CONSERVATIVE, grad_q, dXdx, grad_s);
426 
427     const CeedScalar Grad_E[3] = {grad_s[0].U.E_total, grad_s[1].U.E_total, grad_s[2].U.E_total};
428 
429     for (CeedInt f = 0; f < 4; f++) {
430       for (CeedInt j = 0; j < dim; j++) grad_v[j][f][i] = 0;  // No Change in density or momentum
431       v[f][i] = 0.;
432     }
433 
434     CeedScalar div_u = 0;
435     for (CeedInt j = 0; j < dim; j++) {
436       for (CeedInt k = 0; k < dim; k++) {
437         div_u += grad_s[k].Y.velocity[j];
438       }
439     }
440     CeedScalar strong_conv = s.U.E_total * div_u + DotN(s.Y.velocity, Grad_E, dim);
441 
442     CeedScalar uX[3] = {0.};
443     MatVecNM(dXdx, s.Y.velocity, dim, dim, CEED_NOTRANSPOSE, uX);
444 
445     if (context->strong_form) {  // Strong Galerkin convection term: v div(E u)
446       v[4][i] = -wdetJ * strong_conv;
447       for (CeedInt j = 0; j < dim; j++) grad_v[j][4][i] = 0;
448     } else {  // Weak Galerkin convection term: -dv \cdot (E u)
449       for (CeedInt j = 0; j < dim; j++) grad_v[j][4][i] = wdetJ * s.U.E_total * uX[j];
450       v[4][i] = 0.;
451     }
452 
453     {  // Diffusion
454       CeedScalar Fe[3], Fe_dXdx[3] = {0.};
455 
456       for (CeedInt i = 0; i < dim; i++) Fe[i] = -context->diffusion_coeff * grad_s[i].U.E_total;
457       MatVecNM(dXdx, Fe, dim, dim, CEED_NOTRANSPOSE, Fe_dXdx);
458       for (CeedInt k = 0; k < dim; k++) grad_v[k][4][i] += wdetJ * Fe_dXdx[k];
459     }
460 
461     const CeedScalar TauS = Tau(context, s, dXdx, dim);
462     for (CeedInt j = 0; j < dim; j++) {
463       switch (context->stabilization) {
464         case STAB_NONE:
465           break;
466         case STAB_SU:
467         case STAB_SUPG: {
468           CeedScalar divFdiff_i = context->divFdiff_method != DIV_DIFF_FLUX_PROJ_NONE ? divFdiff[i] : 0.;
469           grad_v[j][4][i] -= wdetJ * TauS * (strong_conv + divFdiff_i) * uX[j];
470         } break;
471       }
472     }
473   }
474   return 0;
475 }
476 
477 CEED_QFUNCTION(RHS_Advection)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
478   return RHSFunction_AdvectionGeneric(ctx, Q, in, out, 3);
479 }
480 
481 CEED_QFUNCTION(RHS_Advection2d)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
482   return RHSFunction_AdvectionGeneric(ctx, Q, in, out, 2);
483 }
484 
485 // *****************************************************************************
486 // This QFunction implements consistent outflow and inflow BCs
487 //      for advection
488 //
489 //  Inflow and outflow faces are determined based on sign(dot(wind, normal)):
490 //    sign(dot(wind, normal)) > 0 : outflow BCs
491 //    sign(dot(wind, normal)) < 0 : inflow BCs
492 //
493 //  Outflow BCs:
494 //    The validity of the weak form of the governing equations is extended to the outflow and the current values of E are applied.
495 //
496 //  Inflow BCs:
497 //    A prescribed Total Energy (E_wind) is applied weakly.
498 // *****************************************************************************
499 CEED_QFUNCTION_HELPER int Advection_InOutFlowGeneric(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out, CeedInt dim) {
500   const CeedScalar(*q)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[0];
501   const CeedScalar(*q_data_sur)    = in[2];
502 
503   CeedScalar(*v)[CEED_Q_VLA]   = (CeedScalar(*)[CEED_Q_VLA])out[0];
504   AdvectionContext context     = (AdvectionContext)ctx;
505   const CeedScalar E_wind      = context->E_wind;
506   const CeedScalar strong_form = context->strong_form;
507   const bool       is_implicit = context->implicit;
508 
509   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
510     const CeedScalar rho  = q[0][i];
511     const CeedScalar u[3] = {q[1][i] / rho, q[2][i] / rho, q[3][i] / rho};
512     const CeedScalar E    = q[4][i];
513 
514     CeedScalar wdetJb, normal[3];
515     QdataBoundaryUnpack_ND(dim, Q, i, q_data_sur, &wdetJb, NULL, normal);
516     wdetJb *= is_implicit ? -1. : 1.;
517 
518     const CeedScalar u_normal = DotN(normal, u, dim);
519 
520     // No Change in density or momentum
521     for (CeedInt j = 0; j < 4; j++) {
522       v[j][i] = 0;
523     }
524     // Implementing in/outflow BCs
525     if (u_normal > 0) {  // outflow
526       v[4][i] = -(1 - strong_form) * wdetJb * E * u_normal;
527     } else {  // inflow
528       v[4][i] = -(1 - strong_form) * wdetJb * E_wind * u_normal;
529     }
530   }
531   return 0;
532 }
533 
534 CEED_QFUNCTION(Advection_InOutFlow)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
535   return Advection_InOutFlowGeneric(ctx, Q, in, out, 3);
536 }
537 
538 CEED_QFUNCTION(Advection2d_InOutFlow)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
539   return Advection_InOutFlowGeneric(ctx, Q, in, out, 2);
540 }
541 
542 // @brief Volume integral for RHS of divergence of diffusive flux direct projection
543 CEED_QFUNCTION_HELPER int DivDiffusiveFluxVolumeRHS_AdvDif_Generic(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out,
544                                                                    const CeedInt dim) {
545   const CeedScalar(*Grad_q)       = in[0];
546   const CeedScalar(*q_data)       = in[1];
547   CeedScalar(*Grad_v)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];
548 
549   AdvectionContext context = (AdvectionContext)ctx;
550 
551   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
552     CeedScalar wdetJ, dXdx[9], F_diff[3] = {0.};
553 
554     QdataUnpack_ND(dim, Q, i, q_data, &wdetJ, dXdx);
555     {  // Get physical diffusive flux
556       CeedScalar Grad_qn[15], grad_E_ref[3];
557 
558       GradUnpackN(Q, i, 5, dim, Grad_q, Grad_qn);
559       CopyN(&Grad_qn[4 * dim], grad_E_ref, dim);
560       MatVecNM(dXdx, grad_E_ref, dim, dim, CEED_NOTRANSPOSE, F_diff);
561       ScaleN(F_diff, -context->diffusion_coeff, dim);
562     }
563 
564     CeedScalar F_diff_dXdx[3] = {0.};
565     MatVecNM(dXdx, F_diff, dim, dim, CEED_NOTRANSPOSE, F_diff_dXdx);
566     for (CeedInt k = 0; k < dim; k++) Grad_v[k][i] = -wdetJ * F_diff_dXdx[k];
567   }
568   return 0;
569 }
570 
571 CEED_QFUNCTION(DivDiffusiveFluxVolumeRHS_AdvDif_2D)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
572   return DivDiffusiveFluxVolumeRHS_AdvDif_Generic(ctx, Q, in, out, 2);
573 }
574 
575 CEED_QFUNCTION(DivDiffusiveFluxVolumeRHS_AdvDif_3D)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
576   return DivDiffusiveFluxVolumeRHS_AdvDif_Generic(ctx, Q, in, out, 3);
577 }
578 
579 // @brief Boundary integral for RHS of divergence of diffusive flux direct projection
580 CEED_QFUNCTION_HELPER int DivDiffusiveFluxBoundaryRHS_AdvDif_Generic(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out,
581                                                                      const CeedInt dim) {
582   const CeedScalar(*Grad_q) = in[0];
583   const CeedScalar(*q_data) = in[1];
584   CeedScalar(*v)            = out[0];
585 
586   AdvectionContext context = (AdvectionContext)ctx;
587 
588   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
589     CeedScalar wdetJ, normal[3], dXdx[9], F_diff[3] = {0.};
590 
591     QdataBoundaryGradientUnpack_ND(dim, Q, i, q_data, &wdetJ, dXdx, normal);
592     {  // Get physical diffusive flux
593       CeedScalar Grad_qn[15], grad_E_ref[3];
594 
595       GradUnpackN(Q, i, 5, dim, Grad_q, Grad_qn);
596       CopyN(&Grad_qn[4 * dim], grad_E_ref, dim);
597       MatVecNM(dXdx, grad_E_ref, dim, dim, CEED_NOTRANSPOSE, F_diff);
598       ScaleN(F_diff, -context->diffusion_coeff, dim);
599     }
600 
601     v[i] = wdetJ * DotN(F_diff, normal, dim);
602   }
603   return 0;
604 }
605 
606 CEED_QFUNCTION(DivDiffusiveFluxBoundaryRHS_AdvDif_2D)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
607   return DivDiffusiveFluxBoundaryRHS_AdvDif_Generic(ctx, Q, in, out, 2);
608 }
609 
610 CEED_QFUNCTION(DivDiffusiveFluxBoundaryRHS_AdvDif_3D)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
611   return DivDiffusiveFluxBoundaryRHS_AdvDif_Generic(ctx, Q, in, out, 3);
612 }
613 
614 // @brief Volume integral for RHS of diffusive flux indirect projection
615 CEED_QFUNCTION_HELPER int DiffusiveFluxRHS_AdvDif_Generic(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out,
616                                                           const CeedInt dim) {
617   const CeedScalar(*Grad_q)  = in[0];
618   const CeedScalar(*q_data)  = in[1];
619   CeedScalar(*v)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];
620 
621   AdvectionContext context = (AdvectionContext)ctx;
622 
623   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
624     CeedScalar wdetJ, dXdx[9], F_diff[3] = {0.};
625 
626     QdataUnpack_ND(dim, Q, i, q_data, &wdetJ, dXdx);
627     {  // Get physical diffusive flux
628       CeedScalar Grad_qn[15], grad_E_ref[3];
629 
630       GradUnpackN(Q, i, 5, dim, Grad_q, Grad_qn);
631       CopyN(&Grad_qn[4 * dim], grad_E_ref, dim);
632       MatVecNM(dXdx, grad_E_ref, dim, dim, CEED_NOTRANSPOSE, F_diff);
633       ScaleN(F_diff, -context->diffusion_coeff, dim);
634     }
635     for (CeedInt k = 0; k < dim; k++) v[k][i] = wdetJ * F_diff[k];
636   }
637   return 0;
638 }
639 
640 CEED_QFUNCTION(DiffusiveFluxRHS_AdvDif_2D)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
641   return DiffusiveFluxRHS_AdvDif_Generic(ctx, Q, in, out, 2);
642 }
643 
644 CEED_QFUNCTION(DiffusiveFluxRHS_AdvDif_3D)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
645   return DiffusiveFluxRHS_AdvDif_Generic(ctx, Q, in, out, 3);
646 }
647