xref: /libCEED/examples/fluids/qfunctions/newtonian_state.h (revision dc805cc4a09d29f27b3febd084feb659e74b9d08)
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 /// Structs and helper functions regarding the state of a newtonian simulation
10 
11 
12 #ifndef newtonian_state_h
13 #define newtonian_state_h
14 
15 #include <math.h>
16 #include <ceed.h>
17 #include "newtonian_types.h"
18 #include "utils.h"
19 
20 typedef struct {
21   CeedScalar pressure;
22   CeedScalar velocity[3];
23   CeedScalar temperature;
24 } StatePrimitive;
25 
26 typedef struct {
27   CeedScalar density;
28   CeedScalar momentum[3];
29   CeedScalar E_total;
30 } StateConservative;
31 
32 typedef struct {
33   StateConservative U;
34   StatePrimitive Y;
35 } State;
36 
37 CEED_QFUNCTION_HELPER StatePrimitive StatePrimitiveFromConservative(
38   NewtonianIdealGasContext gas, StateConservative U, const CeedScalar x[3]) {
39   StatePrimitive Y;
40   for (CeedInt i=0; i<3; i++) Y.velocity[i] = U.momentum[i] / U.density;
41   CeedScalar e_kinetic = .5 * Dot3(Y.velocity, Y.velocity);
42   CeedScalar e_potential = -Dot3(gas->g, x);
43   CeedScalar e_total = U.E_total / U.density;
44   CeedScalar e_internal = e_total - e_kinetic - e_potential;
45   Y.temperature = e_internal / gas->cv;
46   Y.pressure = (gas->cp / gas->cv - 1) * U.density * e_internal;
47   return Y;
48 }
49 
50 CEED_QFUNCTION_HELPER StatePrimitive StatePrimitiveFromConservative_fwd(
51   NewtonianIdealGasContext gas, State s, StateConservative dU,
52   const CeedScalar x[3], const CeedScalar dx[3]) {
53   StatePrimitive dY;
54   for (CeedInt i=0; i<3; i++) {
55     dY.velocity[i] = (dU.momentum[i] - s.Y.velocity[i] * dU.density) / s.U.density;
56   }
57   CeedScalar e_kinetic = .5 * Dot3(s.Y.velocity, s.Y.velocity);
58   CeedScalar de_kinetic = Dot3(dY.velocity, s.Y.velocity);
59   CeedScalar e_potential = -Dot3(gas->g, x);
60   CeedScalar de_potential = -Dot3(gas->g, dx);
61   CeedScalar e_total = s.U.E_total / s.U.density;
62   CeedScalar de_total = (dU.E_total - e_total * dU.density) / s.U.density;
63   CeedScalar e_internal = e_total - e_kinetic - e_potential;
64   CeedScalar de_internal = de_total - de_kinetic - de_potential;
65   dY.temperature = de_internal / gas->cv;
66   dY.pressure = (gas->cp / gas->cv - 1)
67                 * (dU.density * e_internal + s.U.density * de_internal);
68   return dY;
69 }
70 
71 CEED_QFUNCTION_HELPER StateConservative StateConservativeFromPrimitive(
72   NewtonianIdealGasContext gas, StatePrimitive Y, const CeedScalar x[3]) {
73   StateConservative U;
74   CeedScalar R = gas->cp - gas->cv;
75   U.density = Y.pressure / (R * Y.temperature);
76   for (int i=0; i<3; i++) U.momentum[i] = U.density*Y.velocity[i];
77   CeedScalar e_internal = gas->cv * Y.temperature;
78   CeedScalar e_kinetic = .5 * Dot3(Y.velocity, Y.velocity);
79   CeedScalar e_potential = -Dot3(gas->g, x);
80   CeedScalar e_total = e_internal + e_kinetic + e_potential;
81   U.E_total = U.density*e_total;
82   return U;
83 }
84 
85 CEED_QFUNCTION_HELPER StateConservative StateConservativeFromPrimitive_fwd(
86   NewtonianIdealGasContext gas, State s, StatePrimitive dY,
87   const CeedScalar x[3], const CeedScalar dx[3]) {
88   StateConservative dU;
89   CeedScalar R = gas->cp - gas->cv;
90   dU.density = (dY.pressure * s.Y.temperature - s.Y.pressure * dY.temperature) /
91                (R * s.Y.temperature * s.Y.temperature);
92   for (int i=0; i<3; i++) {
93     dU.momentum[i] = dU.density * s.Y.velocity[i] + s.U.density * dY.velocity[i];
94   }
95   CeedScalar e_kinetic = .5 * Dot3(s.Y.velocity, s.Y.velocity);
96   CeedScalar de_kinetic = Dot3(dY.velocity, s.Y.velocity);
97   CeedScalar e_potential = -Dot3(gas->g, x);
98   CeedScalar de_potential = -Dot3(gas->g, dx);
99   CeedScalar e_internal = gas->cv * s.Y.temperature;
100   CeedScalar de_internal = gas->cv * dY.temperature;
101   CeedScalar e_total = e_internal + e_kinetic + e_potential;
102   CeedScalar de_total = de_internal + de_kinetic + de_potential;
103   dU.E_total = dU.density*e_total + s.U.density*de_total;
104   return dU;
105 }
106 
107 CEED_QFUNCTION_HELPER State StateFromU(NewtonianIdealGasContext gas,
108                                        const CeedScalar U[5], const CeedScalar x[3]) {
109   State s;
110   s.U.density = U[0];
111   s.U.momentum[0] = U[1];
112   s.U.momentum[1] = U[2];
113   s.U.momentum[2] = U[3];
114   s.U.E_total = U[4];
115   s.Y = StatePrimitiveFromConservative(gas, s.U, x);
116   return s;
117 }
118 
119 CEED_QFUNCTION_HELPER State StateFromU_fwd(NewtonianIdealGasContext gas,
120     State s, const CeedScalar dU[5],
121     const CeedScalar x[3], const CeedScalar dx[3]) {
122   State ds;
123   ds.U.density = dU[0];
124   ds.U.momentum[0] = dU[1];
125   ds.U.momentum[1] = dU[2];
126   ds.U.momentum[2] = dU[3];
127   ds.U.E_total = dU[4];
128   ds.Y = StatePrimitiveFromConservative_fwd(gas, s, ds.U, x, dx);
129   return ds;
130 }
131 
132 CEED_QFUNCTION_HELPER State StateFromY(NewtonianIdealGasContext gas,
133                                        const CeedScalar Y[5], const CeedScalar x[3]) {
134   State s;
135   s.Y.pressure    = Y[0];
136   s.Y.velocity[0] = Y[1];
137   s.Y.velocity[1] = Y[2];
138   s.Y.velocity[2] = Y[3];
139   s.Y.temperature = Y[4];
140   s.U = StateConservativeFromPrimitive(gas, s.Y, x);
141   return s;
142 }
143 
144 CEED_QFUNCTION_HELPER State StateFromY_fwd(NewtonianIdealGasContext gas,
145     State s, const CeedScalar dY[5],
146     const CeedScalar x[3], const CeedScalar dx[3]) {
147   State ds;
148   ds.Y.pressure    = dY[0];
149   ds.Y.velocity[0] = dY[1];
150   ds.Y.velocity[1] = dY[2];
151   ds.Y.velocity[2] = dY[3];
152   ds.Y.temperature = dY[4];
153   ds.U = StateConservativeFromPrimitive_fwd(gas, s, ds.Y, x, dx);
154   return ds;
155 }
156 
157 CEED_QFUNCTION_HELPER void FluxInviscid(NewtonianIdealGasContext gas, State s,
158                                         StateConservative Flux[3]) {
159   for (CeedInt i=0; i<3; i++) {
160     Flux[i].density = s.U.momentum[i];
161     for (CeedInt j=0; j<3; j++)
162       Flux[i].momentum[j] = s.U.momentum[i] * s.Y.velocity[j]
163                             + s.Y.pressure * (i == j);
164     Flux[i].E_total = (s.U.E_total + s.Y.pressure) * s.Y.velocity[i];
165   }
166 }
167 
168 CEED_QFUNCTION_HELPER void FluxInviscid_fwd(NewtonianIdealGasContext gas,
169     State s, State ds, StateConservative dFlux[3]) {
170   for (CeedInt i=0; i<3; i++) {
171     dFlux[i].density = ds.U.momentum[i];
172     for (CeedInt j=0; j<3; j++)
173       dFlux[i].momentum[j] = ds.U.momentum[i] * s.Y.velocity[j] +
174                              s.U.momentum[i] * ds.Y.velocity[j] + ds.Y.pressure * (i == j);
175     dFlux[i].E_total = (ds.U.E_total + ds.Y.pressure) * s.Y.velocity[i] +
176                        (s.U.E_total + s.Y.pressure) * ds.Y.velocity[i];
177   }
178 }
179 
180 // Kelvin-Mandel notation
181 CEED_QFUNCTION_HELPER void KMStrainRate(const State grad_s[3],
182                                         CeedScalar strain_rate[6]) {
183   const CeedScalar weight = 1 / sqrt(2.);
184   strain_rate[0] = grad_s[0].Y.velocity[0];
185   strain_rate[1] = grad_s[1].Y.velocity[1];
186   strain_rate[2] = grad_s[2].Y.velocity[2];
187   strain_rate[3] = weight * (grad_s[2].Y.velocity[1] + grad_s[1].Y.velocity[2]);
188   strain_rate[4] = weight * (grad_s[2].Y.velocity[0] + grad_s[0].Y.velocity[2]);
189   strain_rate[5] = weight * (grad_s[1].Y.velocity[0] + grad_s[0].Y.velocity[1]);
190 }
191 
192 CEED_QFUNCTION_HELPER void NewtonianStress(NewtonianIdealGasContext gas,
193     const CeedScalar strain_rate[6], CeedScalar stress[6]) {
194   CeedScalar div_u = strain_rate[0] + strain_rate[1] + strain_rate[2];
195   for (CeedInt i=0; i<6; i++) {
196     stress[i] = gas->mu * (2 * strain_rate[i] + gas->lambda * div_u * (i < 3));
197   }
198 }
199 
200 CEED_QFUNCTION_HELPER void ViscousEnergyFlux(NewtonianIdealGasContext gas,
201     StatePrimitive Y, const State grad_s[3], const CeedScalar stress[3][3],
202     CeedScalar Fe[3]) {
203   for (CeedInt i=0; i<3; i++) {
204     Fe[i] = - Y.velocity[0] * stress[0][i]
205             - Y.velocity[1] * stress[1][i]
206             - Y.velocity[2] * stress[2][i]
207             - gas->k * grad_s[i].Y.temperature;
208   }
209 }
210 
211 CEED_QFUNCTION_HELPER void ViscousEnergyFlux_fwd(NewtonianIdealGasContext gas,
212     StatePrimitive Y, StatePrimitive dY, const State grad_ds[3],
213     const CeedScalar stress[3][3],
214     const CeedScalar dstress[3][3],
215     CeedScalar dFe[3]) {
216   for (CeedInt i=0; i<3; i++) {
217     dFe[i] = - Y.velocity[0] * dstress[0][i] - dY.velocity[0] * stress[0][i]
218              - Y.velocity[1] * dstress[1][i] - dY.velocity[1] * stress[1][i]
219              - Y.velocity[2] * dstress[2][i] - dY.velocity[2] * stress[2][i]
220              - gas->k * grad_ds[i].Y.temperature;
221   }
222 }
223 
224 #endif // newtonian_state_h
225