xref: /libCEED/examples/fluids/qfunctions/newtonian_state.h (revision 9ba83ac0e4b1fca39d6fa6737a318a9f0cbc172d)
1 // Copyright (c) 2017-2026, 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 /// Structs and helper functions regarding the state of a newtonian simulation
10 #pragma once
11 
12 #include <ceed/types.h>
13 #ifndef CEED_RUNNING_JIT_PASS
14 #include <math.h>
15 #endif
16 
17 #include "newtonian_types.h"
18 #include "utils.h"
19 
20 typedef struct {
21   CeedScalar density;
22   CeedScalar momentum[3];
23   CeedScalar E_total;
24 } StateConservative;
25 
26 typedef struct {
27   StateConservative U;
28   StatePrimitive    Y;
29 } State;
30 
31 CEED_QFUNCTION_HELPER void UnpackState_U(StateConservative s, CeedScalar U[5]) {
32   U[0] = s.density;
33   for (int i = 0; i < 3; i++) U[i + 1] = s.momentum[i];
34   U[4] = s.E_total;
35 }
36 
37 CEED_QFUNCTION_HELPER void UnpackState_Y(StatePrimitive s, CeedScalar Y[5]) {
38   Y[0] = s.pressure;
39   for (int i = 0; i < 3; i++) Y[i + 1] = s.velocity[i];
40   Y[4] = s.temperature;
41 }
42 
43 CEED_QFUNCTION_HELPER void UnpackState_V(StateEntropy s, CeedScalar V[5]) {
44   V[0] = s.S_density;
45   for (int i = 0; i < 3; i++) V[i + 1] = s.S_momentum[i];
46   V[4] = s.S_energy;
47 }
48 
49 CEED_QFUNCTION_HELPER CeedScalar HeatCapacityRatio(NewtonianIdealGasContext gas) { return gas->cp / gas->cv; }
50 
51 CEED_QFUNCTION_HELPER CeedScalar GasConstant(NewtonianIdealGasContext gas) { return gas->cp - gas->cv; }
52 
53 CEED_QFUNCTION_HELPER CeedScalar Prandtl(NewtonianIdealGasContext gas) { return gas->cp * gas->mu / gas->k; }
54 
55 CEED_QFUNCTION_HELPER CeedScalar SoundSpeed(NewtonianIdealGasContext gas, CeedScalar T) { return sqrt(gas->cp * (HeatCapacityRatio(gas) - 1.) * T); }
56 
57 CEED_QFUNCTION_HELPER CeedScalar Mach(NewtonianIdealGasContext gas, CeedScalar T, CeedScalar u) { return u / SoundSpeed(gas, T); }
58 
59 CEED_QFUNCTION_HELPER CeedScalar TotalSpecificEnthalpy(NewtonianIdealGasContext gas, const State s) {
60   CeedScalar e_kinetic  = 0.5 * Dot3(s.Y.velocity, s.Y.velocity);
61   CeedScalar e_internal = gas->cv * s.Y.temperature;
62   return e_internal + e_kinetic + s.Y.pressure / s.U.density;
63 }
64 
65 CEED_QFUNCTION_HELPER CeedScalar TotalSpecificEnthalpy_fwd(NewtonianIdealGasContext gas, const State s, const State ds) {
66   CeedScalar de_kinetic  = Dot3(ds.Y.velocity, s.Y.velocity);
67   CeedScalar de_internal = gas->cv * ds.Y.temperature;
68   return de_internal + de_kinetic + ds.Y.pressure / s.U.density - s.Y.pressure / Square(s.U.density) * ds.U.density;
69 }
70 
71 CEED_QFUNCTION_HELPER StatePrimitive StatePrimitiveFromConservative(NewtonianIdealGasContext gas, StateConservative U) {
72   StatePrimitive Y;
73   for (CeedInt i = 0; i < 3; i++) Y.velocity[i] = U.momentum[i] / U.density;
74   CeedScalar e_kinetic  = .5 * Dot3(Y.velocity, Y.velocity);
75   CeedScalar e_total    = U.E_total / U.density;
76   CeedScalar e_internal = e_total - e_kinetic;
77   Y.temperature         = e_internal / gas->cv;
78   Y.pressure            = (HeatCapacityRatio(gas) - 1) * U.density * e_internal;
79   return Y;
80 }
81 
82 CEED_QFUNCTION_HELPER StatePrimitive StatePrimitiveFromConservative_fwd(NewtonianIdealGasContext gas, State s, StateConservative dU) {
83   StatePrimitive dY;
84   for (CeedInt i = 0; i < 3; i++) {
85     dY.velocity[i] = (dU.momentum[i] - s.Y.velocity[i] * dU.density) / s.U.density;
86   }
87   CeedScalar e_kinetic   = .5 * Dot3(s.Y.velocity, s.Y.velocity);
88   CeedScalar de_kinetic  = Dot3(dY.velocity, s.Y.velocity);
89   CeedScalar e_total     = s.U.E_total / s.U.density;
90   CeedScalar de_total    = (dU.E_total - e_total * dU.density) / s.U.density;
91   CeedScalar e_internal  = e_total - e_kinetic;
92   CeedScalar de_internal = de_total - de_kinetic;
93   dY.temperature         = de_internal / gas->cv;
94   dY.pressure            = (HeatCapacityRatio(gas) - 1) * (dU.density * e_internal + s.U.density * de_internal);
95   return dY;
96 }
97 
98 CEED_QFUNCTION_HELPER StateEntropy StateEntropyFromPrimitive(NewtonianIdealGasContext gas, StatePrimitive Y) {
99   StateEntropy     V;
100   const CeedScalar gamma     = HeatCapacityRatio(gas);
101   const CeedScalar rho       = Y.pressure / (GasConstant(gas) * Y.temperature);
102   const CeedScalar entropy   = log(Y.pressure) - gamma * log(rho);
103   const CeedScalar rho_div_p = rho / Y.pressure;
104   const CeedScalar e_kinetic = 0.5 * Dot3(Y.velocity, Y.velocity);
105 
106   V.S_density = (gamma - entropy) / (gamma - 1) - rho_div_p * e_kinetic;
107   for (int i = 0; i < 3; i++) V.S_momentum[i] = rho_div_p * Y.velocity[i];
108   V.S_energy = -rho_div_p;
109   return V;
110 }
111 
112 CEED_QFUNCTION_HELPER StateEntropy StateEntropyFromPrimitive_fwd(NewtonianIdealGasContext gas, State s, StatePrimitive dY) {
113   StateEntropy     dV;
114   const CeedScalar gamma = HeatCapacityRatio(gas);
115   CeedScalar       drho  = (dY.pressure * s.Y.temperature - s.Y.pressure * dY.temperature) / (GasConstant(gas) * s.Y.temperature * s.Y.temperature);
116 
117   const CeedScalar e_kinetic  = .5 * Dot3(s.Y.velocity, s.Y.velocity);
118   const CeedScalar de_kinetic = Dot3(dY.velocity, s.Y.velocity);
119   const CeedScalar rho_div_p  = s.U.density / s.Y.pressure;
120   const CeedScalar drho_div_p = (drho * s.Y.pressure - s.U.density * dY.pressure) / Square(s.Y.pressure);
121 
122   CeedScalar dentropy = dY.pressure / s.Y.pressure - gamma * drho / s.U.density;
123 
124   dV.S_density = -dentropy / (gamma - 1) - de_kinetic * rho_div_p - e_kinetic * drho_div_p;
125   for (CeedInt i = 0; i < 3; i++) dV.S_momentum[i] = rho_div_p * dY.velocity[i] + drho_div_p * s.Y.velocity[i];
126   dV.S_energy = -drho_div_p;
127   return dV;
128 }
129 
130 CEED_QFUNCTION_HELPER StatePrimitive StatePrimitiveFromEntropy(NewtonianIdealGasContext gas, StateEntropy V) {
131   StatePrimitive Y;
132   for (int i = 0; i < 3; i++) Y.velocity[i] = -V.S_momentum[i] / V.S_energy;
133   Y.temperature              = -1 / (GasConstant(gas) * V.S_energy);
134   const CeedScalar gamma     = HeatCapacityRatio(gas);
135   const CeedScalar e_kinetic = 0.5 * Dot3(Y.velocity, Y.velocity);
136   const CeedScalar entropy   = gamma - (gamma - 1) * (V.S_density - e_kinetic * V.S_energy);
137   const CeedScalar log_P     = -(entropy + gamma * log(-V.S_energy)) / (gamma - 1);
138   Y.pressure                 = exp(log_P);
139   return Y;
140 }
141 
142 CEED_QFUNCTION_HELPER StatePrimitive StatePrimitiveFromEntropy_fwd(NewtonianIdealGasContext gas, State s, StateEntropy dV) {
143   StatePrimitive dY;
144   StateEntropy   V = StateEntropyFromPrimitive(gas, s.Y);
145   for (int i = 0; i < 3; i++) dY.velocity[i] = -(dV.S_momentum[i] - V.S_momentum[i] * dV.S_energy / V.S_energy) / V.S_energy;
146   dY.temperature              = dV.S_energy / (GasConstant(gas) * V.S_energy * V.S_energy);
147   const CeedScalar gamma      = HeatCapacityRatio(gas);
148   const CeedScalar e_kinetic  = 0.5 * Dot3(s.Y.velocity, s.Y.velocity);
149   const CeedScalar de_kinetic = Dot3(dY.velocity, s.Y.velocity);
150   const CeedScalar dentropy   = (1 - gamma) * (dV.S_density - e_kinetic * dV.S_energy - de_kinetic * V.S_energy);
151   dY.pressure                 = s.Y.pressure * (-dentropy - gamma * dV.S_energy / V.S_energy) / (gamma - 1);
152   return dY;
153 }
154 
155 CEED_QFUNCTION_HELPER StateConservative StateConservativeFromPrimitive(NewtonianIdealGasContext gas, StatePrimitive Y) {
156   StateConservative U;
157   U.density = Y.pressure / (GasConstant(gas) * Y.temperature);
158   for (int i = 0; i < 3; i++) U.momentum[i] = U.density * Y.velocity[i];
159   CeedScalar e_internal = gas->cv * Y.temperature;
160   CeedScalar e_kinetic  = .5 * Dot3(Y.velocity, Y.velocity);
161   CeedScalar e_total    = e_internal + e_kinetic;
162   U.E_total             = U.density * e_total;
163   return U;
164 }
165 
166 CEED_QFUNCTION_HELPER StateConservative StateConservativeFromPrimitive_fwd(NewtonianIdealGasContext gas, State s, StatePrimitive dY) {
167   StateConservative dU;
168   dU.density = (dY.pressure * s.Y.temperature - s.Y.pressure * dY.temperature) / (GasConstant(gas) * s.Y.temperature * s.Y.temperature);
169   for (int i = 0; i < 3; i++) {
170     dU.momentum[i] = dU.density * s.Y.velocity[i] + s.U.density * dY.velocity[i];
171   }
172   CeedScalar e_kinetic   = .5 * Dot3(s.Y.velocity, s.Y.velocity);
173   CeedScalar de_kinetic  = Dot3(dY.velocity, s.Y.velocity);
174   CeedScalar e_internal  = gas->cv * s.Y.temperature;
175   CeedScalar de_internal = gas->cv * dY.temperature;
176   CeedScalar e_total     = e_internal + e_kinetic;
177   CeedScalar de_total    = de_internal + de_kinetic;
178   dU.E_total             = dU.density * e_total + s.U.density * de_total;
179   return dU;
180 }
181 
182 CEED_QFUNCTION_HELPER StateEntropy StateEntropyFromConservative(NewtonianIdealGasContext gas, StateConservative U) {
183   StateEntropy     V;
184   const CeedScalar gamma      = HeatCapacityRatio(gas);
185   const CeedScalar e_kinetic  = .5 * Dot3(U.momentum, U.momentum) / U.density;
186   const CeedScalar e_internal = U.E_total - e_kinetic;
187   const CeedScalar p          = (gamma - 1) * e_internal;
188   const CeedScalar entropy    = log(p) - gamma * log(U.density);
189 
190   V.S_density = (gamma - entropy) / (gamma - 1) - e_kinetic / p;
191   for (int i = 0; i < 3; i++) V.S_momentum[i] = U.momentum[i] / p;
192   V.S_energy = -U.density / p;
193   return V;
194 }
195 
196 CEED_QFUNCTION_HELPER StateEntropy StateEntropyFromConservative_fwd(NewtonianIdealGasContext gas, State s, StateConservative dU) {
197   StateEntropy     dV;
198   const CeedScalar gamma       = HeatCapacityRatio(gas);
199   const CeedScalar e_kinetic   = .5 * Dot3(s.U.momentum, s.U.momentum) / s.U.density;
200   const CeedScalar de_kinetic  = (Dot3(s.U.momentum, dU.momentum) - e_kinetic * dU.density) / s.U.density;
201   const CeedScalar de_internal = dU.E_total - de_kinetic;
202   const CeedScalar p           = s.Y.pressure;
203   const CeedScalar dp          = (gamma - 1) * de_internal;
204 
205   CeedScalar dentropy = dp / p - gamma * dU.density / s.U.density;
206 
207   dV.S_density = -dentropy / (gamma - 1) - de_kinetic / p + dp * e_kinetic / Square(p);
208   for (CeedInt i = 0; i < 3; i++) {
209     dV.S_momentum[i] = (dU.momentum[i] - s.U.momentum[i] * dp / p) / p;
210   }
211   dV.S_energy = -(dU.density - s.U.density * dp / p) / p;
212   return dV;
213 }
214 
215 CEED_QFUNCTION_HELPER StateConservative StateConservativeFromEntropy(NewtonianIdealGasContext gas, StateEntropy V) {
216   StateConservative U;
217   CeedScalar        velocity[3];
218   for (int i = 0; i < 3; i++) velocity[i] = -V.S_momentum[i] / V.S_energy;
219   const CeedScalar gamma     = HeatCapacityRatio(gas);
220   const CeedScalar e_kinetic = 0.5 * Dot3(velocity, velocity);
221   const CeedScalar entropy   = gamma - (gamma - 1) * (V.S_density - e_kinetic * V.S_energy);
222   const CeedScalar log_rho   = -(entropy + log(-V.S_energy)) / (gamma - 1);
223   U.density                  = exp(log_rho);
224   for (int i = 0; i < 3; i++) U.momentum[i] = U.density * velocity[i];
225 
226   const CeedScalar e_internal = -gas->cv / (GasConstant(gas) * V.S_energy);
227   U.E_total                   = U.density * (e_internal + e_kinetic);
228   return U;
229 }
230 
231 CEED_QFUNCTION_HELPER StateConservative StateConservativeFromEntropy_fwd(NewtonianIdealGasContext gas, State s, StateEntropy dV) {
232   StateConservative dU;
233   CeedScalar        dvelocity[3];
234   StateEntropy      V = StateEntropyFromPrimitive(gas, s.Y);
235   for (int i = 0; i < 3; i++) dvelocity[i] = (-dV.S_momentum[i] - s.Y.velocity[i] * dV.S_energy) / V.S_energy;
236   const CeedScalar gamma      = HeatCapacityRatio(gas);
237   const CeedScalar e_kinetic  = 0.5 * Dot3(s.Y.velocity, s.Y.velocity);
238   const CeedScalar de_kinetic = Dot3(dvelocity, s.Y.velocity);
239   const CeedScalar entropy    = gamma - (gamma - 1) * (V.S_density - e_kinetic * V.S_energy);
240   const CeedScalar dentropy   = -(gamma - 1) * (dV.S_density - (de_kinetic * V.S_energy + e_kinetic * dV.S_energy));
241   const CeedScalar log_rho    = -(entropy + log(-V.S_energy)) / (gamma - 1);
242   const CeedScalar rho        = exp(log_rho);
243   dU.density                  = -rho / (gamma - 1) * (dentropy + dV.S_energy / V.S_energy);
244   for (int i = 0; i < 3; i++) dU.momentum[i] = dU.density * s.Y.velocity[i] + s.U.density * dvelocity[i];
245 
246   const CeedScalar e_internal  = -gas->cv / (GasConstant(gas) * V.S_energy);
247   const CeedScalar de_internal = gas->cv * dV.S_energy / (GasConstant(gas) * V.S_energy * V.S_energy);
248   const CeedScalar e_total     = e_internal + e_kinetic;
249   dU.E_total                   = dU.density * e_total + s.U.density * (de_internal + de_kinetic);
250   return dU;
251 }
252 
253 CEED_QFUNCTION_HELPER State StateFromPrimitive(NewtonianIdealGasContext gas, StatePrimitive Y) {
254   StateConservative U = StateConservativeFromPrimitive(gas, Y);
255   State             s;
256   s.U = U;
257   s.Y = Y;
258   return s;
259 }
260 
261 CEED_QFUNCTION_HELPER State StateFromPrimitive_fwd(NewtonianIdealGasContext gas, State s, StatePrimitive dY) {
262   StateConservative dU = StateConservativeFromPrimitive_fwd(gas, s, dY);
263   State             ds;
264   ds.U = dU;
265   ds.Y = dY;
266   return ds;
267 }
268 
269 // linear combination of n states
270 CEED_QFUNCTION_HELPER StateConservative StateConservativeMult(CeedInt n, const CeedScalar a[], const StateConservative X[]) {
271   StateConservative R = {0};
272   for (CeedInt i = 0; i < n; i++) {
273     R.density += a[i] * X[i].density;
274     for (int j = 0; j < 3; j++) R.momentum[j] += a[i] * X[i].momentum[j];
275     R.E_total += a[i] * X[i].E_total;
276   }
277   return R;
278 }
279 
280 CEED_QFUNCTION_HELPER StateConservative StateConservativeAXPBYPCZ(CeedScalar a, StateConservative X, CeedScalar b, StateConservative Y, CeedScalar c,
281                                                                   StateConservative Z) {
282   StateConservative R;
283   R.density = a * X.density + b * Y.density + c * Z.density;
284   for (int i = 0; i < 3; i++) R.momentum[i] = a * X.momentum[i] + b * Y.momentum[i] + c * Z.momentum[i];
285   R.E_total = a * X.E_total + b * Y.E_total + c * Z.E_total;
286   return R;
287 }
288 
289 CEED_QFUNCTION_HELPER void StateToU(NewtonianIdealGasContext gas, const State input, CeedScalar U[5]) { UnpackState_U(input.U, U); }
290 
291 CEED_QFUNCTION_HELPER void StateToY(NewtonianIdealGasContext gas, const State input, CeedScalar Y[5]) { UnpackState_Y(input.Y, Y); }
292 
293 CEED_QFUNCTION_HELPER void StateToV(NewtonianIdealGasContext gas, const State input, CeedScalar V[5]) {
294   StateEntropy state_V = StateEntropyFromPrimitive(gas, input.Y);
295   UnpackState_V(state_V, V);
296 }
297 
298 CEED_QFUNCTION_HELPER void StateToQ(NewtonianIdealGasContext gas, const State input, CeedScalar Q[5], StateVariable state_var) {
299   switch (state_var) {
300     case STATEVAR_CONSERVATIVE:
301       StateToU(gas, input, Q);
302       break;
303     case STATEVAR_PRIMITIVE:
304       StateToY(gas, input, Q);
305       break;
306     case STATEVAR_ENTROPY:
307       StateToV(gas, input, Q);
308       break;
309   }
310 }
311 
312 CEED_QFUNCTION_HELPER void StateToQ_fwd(NewtonianIdealGasContext gas, const State input, const State dinput, CeedScalar dQ[5],
313                                         StateVariable state_var) {
314   switch (state_var) {
315     case STATEVAR_CONSERVATIVE:
316     case STATEVAR_PRIMITIVE:
317       StateToQ(gas, dinput, dQ, state_var);
318       break;
319     case STATEVAR_ENTROPY: {
320       StateEntropy dstate_v;
321 
322       dstate_v = StateEntropyFromPrimitive_fwd(gas, input, dinput.Y);
323       UnpackState_V(dstate_v, dQ);
324     } break;
325   }
326 }
327 
328 CEED_QFUNCTION_HELPER State StateFromU(NewtonianIdealGasContext gas, const CeedScalar U[5]) {
329   State s;
330   s.U.density     = U[0];
331   s.U.momentum[0] = U[1];
332   s.U.momentum[1] = U[2];
333   s.U.momentum[2] = U[3];
334   s.U.E_total     = U[4];
335   s.Y             = StatePrimitiveFromConservative(gas, s.U);
336   return s;
337 }
338 
339 CEED_QFUNCTION_HELPER State StateFromU_fwd(NewtonianIdealGasContext gas, State s, const CeedScalar dU[5]) {
340   State ds;
341   ds.U.density     = dU[0];
342   ds.U.momentum[0] = dU[1];
343   ds.U.momentum[1] = dU[2];
344   ds.U.momentum[2] = dU[3];
345   ds.U.E_total     = dU[4];
346   ds.Y             = StatePrimitiveFromConservative_fwd(gas, s, ds.U);
347   return ds;
348 }
349 
350 CEED_QFUNCTION_HELPER State StateFromY(NewtonianIdealGasContext gas, const CeedScalar Y[5]) {
351   State s;
352   s.Y.pressure    = Y[0];
353   s.Y.velocity[0] = Y[1];
354   s.Y.velocity[1] = Y[2];
355   s.Y.velocity[2] = Y[3];
356   s.Y.temperature = Y[4];
357   s.U             = StateConservativeFromPrimitive(gas, s.Y);
358   return s;
359 }
360 
361 CEED_QFUNCTION_HELPER State StateFromY_fwd(NewtonianIdealGasContext gas, State s, const CeedScalar dY[5]) {
362   State ds;
363   ds.Y.pressure    = dY[0];
364   ds.Y.velocity[0] = dY[1];
365   ds.Y.velocity[1] = dY[2];
366   ds.Y.velocity[2] = dY[3];
367   ds.Y.temperature = dY[4];
368   ds.U             = StateConservativeFromPrimitive_fwd(gas, s, ds.Y);
369   return ds;
370 }
371 
372 CEED_QFUNCTION_HELPER State StateFromV(NewtonianIdealGasContext gas, const CeedScalar V[5]) {
373   State        s;
374   StateEntropy state_V;
375   state_V.S_density     = V[0];
376   state_V.S_momentum[0] = V[1];
377   state_V.S_momentum[1] = V[2];
378   state_V.S_momentum[2] = V[3];
379   state_V.S_energy      = V[4];
380   s.U                   = StateConservativeFromEntropy(gas, state_V);
381   s.Y                   = StatePrimitiveFromEntropy(gas, state_V);
382   return s;
383 }
384 
385 CEED_QFUNCTION_HELPER State StateFromV_fwd(NewtonianIdealGasContext gas, State s, const CeedScalar dV[5]) {
386   State        ds;
387   StateEntropy state_dV;
388   state_dV.S_density     = dV[0];
389   state_dV.S_momentum[0] = dV[1];
390   state_dV.S_momentum[1] = dV[2];
391   state_dV.S_momentum[2] = dV[3];
392   state_dV.S_energy      = dV[4];
393   ds.U                   = StateConservativeFromEntropy_fwd(gas, s, state_dV);
394   ds.Y                   = StatePrimitiveFromEntropy_fwd(gas, s, state_dV);
395   return ds;
396 }
397 
398 CEED_QFUNCTION_HELPER State StateFromQ(NewtonianIdealGasContext gas, const CeedScalar Q[5], StateVariable state_var) {
399   State s;
400   switch (state_var) {
401     case STATEVAR_CONSERVATIVE:
402       s = StateFromU(gas, Q);
403       break;
404     case STATEVAR_PRIMITIVE:
405       s = StateFromY(gas, Q);
406       break;
407     case STATEVAR_ENTROPY:
408       s = StateFromV(gas, Q);
409       break;
410   }
411   return s;
412 }
413 
414 CEED_QFUNCTION_HELPER State StateFromQ_fwd(NewtonianIdealGasContext gas, State s, const CeedScalar dQ[5], StateVariable state_var) {
415   State ds;
416   switch (state_var) {
417     case STATEVAR_CONSERVATIVE:
418       ds = StateFromU_fwd(gas, s, dQ);
419       break;
420     case STATEVAR_PRIMITIVE:
421       ds = StateFromY_fwd(gas, s, dQ);
422       break;
423     case STATEVAR_ENTROPY:
424       ds = StateFromV_fwd(gas, s, dQ);
425       break;
426   }
427   return ds;
428 }
429 
430 CEED_QFUNCTION_HELPER void FluxInviscid(NewtonianIdealGasContext gas, State s, StateConservative Flux[3]) {
431   for (CeedInt i = 0; i < 3; i++) {
432     Flux[i].density = s.U.momentum[i];
433     for (CeedInt j = 0; j < 3; j++) Flux[i].momentum[j] = s.U.momentum[i] * s.Y.velocity[j] + s.Y.pressure * (i == j);
434     Flux[i].E_total = (s.U.E_total + s.Y.pressure) * s.Y.velocity[i];
435   }
436 }
437 
438 CEED_QFUNCTION_HELPER void FluxInviscid_fwd(NewtonianIdealGasContext gas, State s, State ds, StateConservative dFlux[3]) {
439   for (CeedInt i = 0; i < 3; i++) {
440     dFlux[i].density = ds.U.momentum[i];
441     for (CeedInt j = 0; j < 3; j++) {
442       dFlux[i].momentum[j] = ds.U.momentum[i] * s.Y.velocity[j] + s.U.momentum[i] * ds.Y.velocity[j] + ds.Y.pressure * (i == j);
443     }
444     dFlux[i].E_total = (ds.U.E_total + ds.Y.pressure) * s.Y.velocity[i] + (s.U.E_total + s.Y.pressure) * ds.Y.velocity[i];
445   }
446 }
447 
448 CEED_QFUNCTION_HELPER StateConservative FluxInviscidDotNormal(NewtonianIdealGasContext gas, State s, const CeedScalar normal[3]) {
449   StateConservative Flux[3], Flux_dot_n = {0};
450   FluxInviscid(gas, s, Flux);
451   for (CeedInt i = 0; i < 3; i++) {
452     Flux_dot_n.density += Flux[i].density * normal[i];
453     for (CeedInt j = 0; j < 3; j++) Flux_dot_n.momentum[j] += Flux[i].momentum[j] * normal[i];
454     Flux_dot_n.E_total += Flux[i].E_total * normal[i];
455   }
456   return Flux_dot_n;
457 }
458 
459 CEED_QFUNCTION_HELPER StateConservative FluxInviscidDotNormal_fwd(NewtonianIdealGasContext gas, State s, State ds, const CeedScalar normal[3]) {
460   StateConservative dFlux[3], Flux_dot_n = {0};
461   FluxInviscid_fwd(gas, s, ds, dFlux);
462   for (CeedInt i = 0; i < 3; i++) {
463     Flux_dot_n.density += dFlux[i].density * normal[i];
464     for (CeedInt j = 0; j < 3; j++) Flux_dot_n.momentum[j] += dFlux[i].momentum[j] * normal[i];
465     Flux_dot_n.E_total += dFlux[i].E_total * normal[i];
466   }
467   return Flux_dot_n;
468 }
469 
470 CEED_QFUNCTION_HELPER void FluxInviscidStrong(NewtonianIdealGasContext gas, State s, State ds[3], CeedScalar strong_conv[5]) {
471   for (CeedInt i = 0; i < 5; i++) strong_conv[i] = 0;
472   for (CeedInt i = 0; i < 3; i++) {
473     StateConservative dF[3];
474     FluxInviscid_fwd(gas, s, ds[i], dF);
475     CeedScalar dF_i[5];
476     UnpackState_U(dF[i], dF_i);
477     for (CeedInt j = 0; j < 5; j++) strong_conv[j] += dF_i[j];
478   }
479 }
480 
481 CEED_QFUNCTION_HELPER void FluxTotal(const StateConservative F_inviscid[3], CeedScalar stress[3][3], CeedScalar Fe[3], CeedScalar Flux[5][3]) {
482   for (CeedInt j = 0; j < 3; j++) {
483     Flux[0][j] = F_inviscid[j].density;
484     for (CeedInt k = 0; k < 3; k++) Flux[k + 1][j] = F_inviscid[j].momentum[k] - stress[k][j];
485     Flux[4][j] = F_inviscid[j].E_total + Fe[j];
486   }
487 }
488 
489 CEED_QFUNCTION_HELPER void FluxTotal_Boundary(const StateConservative F_inviscid[3], const CeedScalar stress[3][3], const CeedScalar Fe[3],
490                                               const CeedScalar normal[3], CeedScalar Flux[5]) {
491   for (CeedInt j = 0; j < 5; j++) Flux[j] = 0.;
492   for (CeedInt j = 0; j < 3; j++) {
493     Flux[0] += F_inviscid[j].density * normal[j];
494     for (CeedInt k = 0; k < 3; k++) {
495       Flux[k + 1] += (F_inviscid[j].momentum[k] - stress[k][j]) * normal[j];
496     }
497     Flux[4] += (F_inviscid[j].E_total + Fe[j]) * normal[j];
498   }
499 }
500 
501 CEED_QFUNCTION_HELPER void FluxTotal_RiemannBoundary(const StateConservative F_inviscid_normal, const CeedScalar stress[3][3], const CeedScalar Fe[3],
502                                                      const CeedScalar normal[3], CeedScalar Flux[5]) {
503   Flux[0] = F_inviscid_normal.density;
504   for (CeedInt k = 0; k < 3; k++) Flux[k + 1] = F_inviscid_normal.momentum[k];
505   Flux[4] = F_inviscid_normal.E_total;
506   for (CeedInt j = 0; j < 3; j++) {
507     for (CeedInt k = 0; k < 3; k++) {
508       Flux[k + 1] -= stress[k][j] * normal[j];
509     }
510     Flux[4] += Fe[j] * normal[j];
511   }
512 }
513 
514 CEED_QFUNCTION_HELPER void VelocityGradient(const State grad_s[3], CeedScalar grad_velocity[3][3]) {
515   grad_velocity[0][0] = grad_s[0].Y.velocity[0];
516   grad_velocity[0][1] = grad_s[1].Y.velocity[0];
517   grad_velocity[0][2] = grad_s[2].Y.velocity[0];
518   grad_velocity[1][0] = grad_s[0].Y.velocity[1];
519   grad_velocity[1][1] = grad_s[1].Y.velocity[1];
520   grad_velocity[1][2] = grad_s[2].Y.velocity[1];
521   grad_velocity[2][0] = grad_s[0].Y.velocity[2];
522   grad_velocity[2][1] = grad_s[1].Y.velocity[2];
523   grad_velocity[2][2] = grad_s[2].Y.velocity[2];
524 }
525 
526 CEED_QFUNCTION_HELPER void KMStrainRate(const CeedScalar grad_velocity[3][3], CeedScalar strain_rate[6]) {
527   const CeedScalar weight = 1 / sqrt(2.);  // Really sqrt(2.) / 2
528   strain_rate[0]          = grad_velocity[0][0];
529   strain_rate[1]          = grad_velocity[1][1];
530   strain_rate[2]          = grad_velocity[2][2];
531   strain_rate[3]          = weight * (grad_velocity[1][2] + grad_velocity[2][1]);
532   strain_rate[4]          = weight * (grad_velocity[0][2] + grad_velocity[2][0]);
533   strain_rate[5]          = weight * (grad_velocity[0][1] + grad_velocity[1][0]);
534 }
535 
536 // Kelvin-Mandel notation
537 CEED_QFUNCTION_HELPER void KMStrainRate_State(const State grad_s[3], CeedScalar strain_rate[6]) {
538   CeedScalar grad_velocity[3][3];
539   VelocityGradient(grad_s, grad_velocity);
540   KMStrainRate(grad_velocity, strain_rate);
541 }
542 
543 //@brief Given velocity gradient du_i/dx_j, return 0.5*(du_i/dx_j - du_j/dx_i)
544 CEED_QFUNCTION_HELPER void RotationRate(const CeedScalar grad_velocity[3][3], CeedScalar rotation_rate[3][3]) {
545   rotation_rate[0][0] = 0;
546   rotation_rate[1][1] = 0;
547   rotation_rate[2][2] = 0;
548   rotation_rate[1][2] = 0.5 * (grad_velocity[1][2] - grad_velocity[2][1]);
549   rotation_rate[0][2] = 0.5 * (grad_velocity[0][2] - grad_velocity[2][0]);
550   rotation_rate[0][1] = 0.5 * (grad_velocity[0][1] - grad_velocity[1][0]);
551   rotation_rate[2][1] = -rotation_rate[1][2];
552   rotation_rate[2][0] = -rotation_rate[0][2];
553   rotation_rate[1][0] = -rotation_rate[0][1];
554 }
555 
556 CEED_QFUNCTION_HELPER void NewtonianStress(NewtonianIdealGasContext gas, const CeedScalar strain_rate[6], CeedScalar stress[6]) {
557   CeedScalar div_u = strain_rate[0] + strain_rate[1] + strain_rate[2];
558   for (CeedInt i = 0; i < 6; i++) {
559     stress[i] = gas->mu * (2 * strain_rate[i] + gas->lambda * div_u * (i < 3));
560   }
561 }
562 
563 CEED_QFUNCTION_HELPER void ViscousEnergyFlux(NewtonianIdealGasContext gas, StatePrimitive Y, const State grad_s[3], const CeedScalar stress[3][3],
564                                              CeedScalar Fe[3]) {
565   for (CeedInt i = 0; i < 3; i++) {
566     Fe[i] = -Y.velocity[0] * stress[0][i] - Y.velocity[1] * stress[1][i] - Y.velocity[2] * stress[2][i] - gas->k * grad_s[i].Y.temperature;
567   }
568 }
569 
570 CEED_QFUNCTION_HELPER void ViscousEnergyFlux_fwd(NewtonianIdealGasContext gas, StatePrimitive Y, StatePrimitive dY, const State grad_ds[3],
571                                                  const CeedScalar stress[3][3], const CeedScalar dstress[3][3], CeedScalar dFe[3]) {
572   for (CeedInt i = 0; i < 3; i++) {
573     dFe[i] = -Y.velocity[0] * dstress[0][i] - dY.velocity[0] * stress[0][i] - Y.velocity[1] * dstress[1][i] - dY.velocity[1] * stress[1][i] -
574              Y.velocity[2] * dstress[2][i] - dY.velocity[2] * stress[2][i] - gas->k * grad_ds[i].Y.temperature;
575   }
576 }
577 
578 CEED_QFUNCTION_HELPER void Vorticity(const State grad_s[3], CeedScalar vorticity[3]) {
579   CeedScalar grad_velocity[3][3];
580   VelocityGradient(grad_s, grad_velocity);
581   Curl3(grad_velocity, vorticity);
582 }
583 
584 CEED_QFUNCTION_HELPER void StatePhysicalGradientFromReference(CeedInt Q, CeedInt i, NewtonianIdealGasContext gas, State s, StateVariable state_var,
585                                                               const CeedScalar *grad_q, const CeedScalar dXdx[3][3], State grad_s[3]) {
586   for (CeedInt k = 0; k < 3; k++) {
587     CeedScalar dqi[5];
588     for (CeedInt j = 0; j < 5; j++) {
589       dqi[j] =
590           grad_q[(Q * 5) * 0 + Q * j + i] * dXdx[0][k] + grad_q[(Q * 5) * 1 + Q * j + i] * dXdx[1][k] + grad_q[(Q * 5) * 2 + Q * j + i] * dXdx[2][k];
591     }
592     grad_s[k] = StateFromQ_fwd(gas, s, dqi, state_var);
593   }
594 }
595 
596 CEED_QFUNCTION_HELPER void StatePhysicalGradientFromReference_Boundary(CeedInt Q, CeedInt i, NewtonianIdealGasContext gas, State s,
597                                                                        StateVariable state_var, const CeedScalar *grad_q, const CeedScalar dXdx[2][3],
598                                                                        State grad_s[3]) {
599   for (CeedInt k = 0; k < 3; k++) {
600     CeedScalar dqi[5];
601     for (CeedInt j = 0; j < 5; j++) {
602       dqi[j] = grad_q[(Q * 5) * 0 + Q * j + i] * dXdx[0][k] + grad_q[(Q * 5) * 1 + Q * j + i] * dXdx[1][k];
603     }
604     grad_s[k] = StateFromQ_fwd(gas, s, dqi, state_var);
605   }
606 }
607