xref: /libCEED/examples/fluids/qfunctions/setupgeo.h (revision 17b5e52fb5f6c474a1e9fc79dd3f8a824f1b6293)
1 // Copyright (c) 2017-2023, 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 /// Geometric factors (3D) for Navier-Stokes example using PETSc
10 
11 #ifndef setup_geo_h
12 #define setup_geo_h
13 
14 #include <ceed.h>
15 #include <math.h>
16 
17 #include "setupgeo_helpers.h"
18 
19 // *****************************************************************************
20 // This QFunction sets up the geometric factors required for integration and coordinate transformations
21 //
22 // Reference (parent) coordinates: X
23 // Physical (current) coordinates: x
24 // Change of coordinate matrix: dxdX_{i,j} = x_{i,j} (indicial notation)
25 // Inverse of change of coordinate matrix: dXdx_{i,j} = (detJ^-1) * X_{i,j}
26 //
27 // All quadrature data is stored in 10 field vector of quadrature data.
28 //
29 // We require the determinant of the Jacobian to properly compute integrals of the form: int( v u )
30 //
31 // Determinant of Jacobian:
32 //   detJ = J11*A11 + J21*A12 + J31*A13
33 //     Jij = Jacobian entry ij
34 //     Aij = Adjugate ij
35 //
36 // Stored: w detJ
37 //   in q_data[0]
38 //
39 // We require the transpose of the inverse of the Jacobian to properly compute integrals of the form: int( gradv u )
40 //
41 // Inverse of Jacobian:
42 //   dXdx_i,j = Aij / detJ
43 //
44 // Stored: Aij / detJ
45 //   in q_data[1:9] as
46 //   (detJ^-1) * [A11 A12 A13]
47 //               [A21 A22 A23]
48 //               [A31 A32 A33]
49 // *****************************************************************************
50 CEED_QFUNCTION(Setup)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
51   const CeedScalar(*J)[3][CEED_Q_VLA] = (const CeedScalar(*)[3][CEED_Q_VLA])in[0];
52   const CeedScalar(*w)                = in[1];
53   CeedScalar(*q_data)[CEED_Q_VLA]     = (CeedScalar(*)[CEED_Q_VLA])out[0];
54 
55   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
56     CeedScalar detJ, dXdx[3][3];
57     InvertMappingJacobian_3D(Q, i, J, dXdx, &detJ);
58     q_data[0][i] = w[i] * detJ;
59     q_data[1][i] = dXdx[0][0];
60     q_data[2][i] = dXdx[0][1];
61     q_data[3][i] = dXdx[0][2];
62     q_data[4][i] = dXdx[1][0];
63     q_data[5][i] = dXdx[1][1];
64     q_data[6][i] = dXdx[1][2];
65     q_data[7][i] = dXdx[2][0];
66     q_data[8][i] = dXdx[2][1];
67     q_data[9][i] = dXdx[2][2];
68   }
69   return 0;
70 }
71 
72 // *****************************************************************************
73 // This QFunction sets up the geometric factor required for integration when reference coordinates are in 2D and the physical coordinates are in 3D
74 //
75 // Reference (parent) 2D coordinates: X
76 // Physical (current) 3D coordinates: x
77 // Change of coordinate matrix:
78 //   dxdX_{i,j} = dx_i/dX_j (indicial notation) [3 * 2]
79 // Inverse change of coordinate matrix:
80 //   dXdx_{i,j} = dX_i/dx_j (indicial notation) [2 * 3]
81 //
82 // (J1,J2,J3) is given by the cross product of the columns of dxdX_{i,j}
83 //
84 // detJb is the magnitude of (J1,J2,J3)
85 //
86 // dXdx is calculated via Moore–Penrose inverse:
87 //
88 //   dX_i/dx_j = (dxdX^T dxdX)^(-1) dxdX
89 //             = (dx_l/dX_i * dx_l/dX_k)^(-1) dx_j/dX_k
90 //
91 // All quadrature data is stored in 10 field vector of quadrature data.
92 //
93 // We require the determinant of the Jacobian to properly compute integrals of
94 //   the form: int( u v )
95 //
96 // Stored: w detJb
97 //   in q_data_sur[0]
98 //
99 // Normal vector = (J1,J2,J3) / detJb
100 //
101 //   - TODO Could possibly remove normal vector, as it could be calculated in the Qfunction from dXdx
102 //    See https://github.com/CEED/libCEED/pull/868#discussion_r871979484
103 // Stored: (J1,J2,J3) / detJb
104 //   in q_data_sur[1:3] as
105 //   (detJb^-1) * [ J1 ]
106 //                [ J2 ]
107 //                [ J3 ]
108 //
109 // Stored: dXdx_{i,j}
110 //   in q_data_sur[4:9] as
111 //    [dXdx_11 dXdx_12 dXdx_13]
112 //    [dXdx_21 dXdx_22 dXdx_23]
113 // *****************************************************************************
114 CEED_QFUNCTION(SetupBoundary)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
115   const CeedScalar(*J)[3][CEED_Q_VLA] = (const CeedScalar(*)[3][CEED_Q_VLA])in[0];
116   const CeedScalar(*w)                = in[1];
117   CeedScalar(*q_data_sur)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];
118 
119   CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
120     CeedScalar detJb, normal[3], dXdx[2][3];
121 
122     NormalVectorFromdxdX_3D(Q, i, J, normal, &detJb);
123     q_data_sur[0][i] = w[i] * detJb;
124     q_data_sur[1][i] = normal[0];
125     q_data_sur[2][i] = normal[1];
126     q_data_sur[3][i] = normal[2];
127 
128     InvertBoundaryMappingJacobian_3D(Q, i, J, dXdx);
129     q_data_sur[4][i] = dXdx[0][0];
130     q_data_sur[5][i] = dXdx[0][1];
131     q_data_sur[6][i] = dXdx[0][2];
132     q_data_sur[7][i] = dXdx[1][0];
133     q_data_sur[8][i] = dXdx[1][1];
134     q_data_sur[9][i] = dXdx[1][2];
135   }
136   return 0;
137 }
138 
139 // *****************************************************************************
140 
141 #endif  // setup_geo_h
142