xref: /libCEED/examples/fluids/qfunctions/setupgeo2d.h (revision 8ec64e9ae9d5df169dba8c8ee61d8ec8907b8f80)
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 /// Geometric factors (2D) for Navier-Stokes example using PETSc
10 
11 #ifndef setup_geo_2d_h
12 #define setup_geo_2d_h
13 
14 #include <ceed.h>
15 #include <math.h>
16 
17 // *****************************************************************************
18 // This QFunction sets up the geometric factors required for integration and coordinate transformations
19 //
20 // Reference (parent) coordinates: X
21 // Physical (current) coordinates: x
22 // Change of coordinate matrix: dxdX_{i,j} = x_{i,j} (indicial notation)
23 // Inverse of change of coordinate matrix: dXdx_{i,j} = (detJ^-1) * X_{i,j}
24 //
25 // All quadrature data is stored in 10 field vector of quadrature data.
26 //
27 // We require the determinant of the Jacobian to properly compute integrals of the form: int( v u )
28 //
29 // Determinant of Jacobian:
30 //   detJ = J11*J22 - J21*J12
31 //     Jij = Jacobian entry ij
32 //
33 // Stored: w detJ
34 //   in q_data[0]
35 //
36 // We require the transpose of the inverse of the Jacobian to properly compute integrals of the form: int( gradv u )
37 //
38 // Inverse of Jacobian:
39 //   dXdx_i,j = Aij / detJ
40 //   Aij = Adjoint ij
41 //
42 // Stored: Aij / detJ
43 //   in q_data[1:4] as
44 //   (detJ^-1) * [A11 A12]
45 //               [A21 A22]
46 // *****************************************************************************
47 CEED_QFUNCTION(Setup2d)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
48   // Inputs
49   const CeedScalar(*J)[2][CEED_Q_VLA] = (const CeedScalar(*)[2][CEED_Q_VLA])in[0];
50   const CeedScalar(*w)                = in[1];
51 
52   // Outputs
53   CeedScalar(*q_data)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];
54 
55   CeedPragmaSIMD
56       // Quadrature Point Loop
57       for (CeedInt i = 0; i < Q; i++) {
58     // Setup
59     const CeedScalar J11  = J[0][0][i];
60     const CeedScalar J21  = J[0][1][i];
61     const CeedScalar J12  = J[1][0][i];
62     const CeedScalar J22  = J[1][1][i];
63     const CeedScalar detJ = J11 * J22 - J21 * J12;
64 
65     // Qdata
66     // -- Interp-to-Interp q_data
67     q_data[0][i] = w[i] * detJ;
68     // -- Interp-to-Grad q_data
69     // Inverse of change of coordinate matrix: X_i,j
70     q_data[1][i] = J22 / detJ;
71     q_data[2][i] = -J12 / detJ;
72     q_data[3][i] = -J21 / detJ;
73     q_data[4][i] = J11 / detJ;
74   }  // End of Quadrature Point Loop
75 
76   // Return
77   return 0;
78 }
79 
80 // *****************************************************************************
81 // This QFunction sets up the geometric factor required for integration when reference coordinates are in 1D and the physical coordinates are in 2D
82 //
83 // Reference (parent) 1D coordinates: X
84 // Physical (current) 2D coordinates: x
85 // Change of coordinate vector:
86 //           J1 = dx_1/dX
87 //           J2 = dx_2/dX
88 //
89 // detJb is the magnitude of (J1,J2)
90 //
91 // All quadrature data is stored in 3 field vector of quadrature data.
92 //
93 // We require the determinant of the Jacobian to properly compute integrals of the form: int( u v )
94 //
95 // Stored: w detJb
96 //   in q_data_sur[0]
97 //
98 // Normal vector is given by the cross product of (J1,J2)/detJ and ẑ
99 //
100 // Stored: (J1,J2,0) x (0,0,1) / detJb
101 //   in q_data_sur[1:2] as
102 //   (detJb^-1) * [ J2 ]
103 //                [-J1 ]
104 // *****************************************************************************
105 CEED_QFUNCTION(SetupBoundary2d)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
106   // Inputs
107   const CeedScalar(*J)[CEED_Q_VLA] = (const CeedScalar(*)[CEED_Q_VLA])in[0];
108   const CeedScalar(*w)             = in[1];
109 
110   // Outputs
111   CeedScalar(*q_data_sur)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];
112 
113   CeedPragmaSIMD
114       // Quadrature Point Loop
115       for (CeedInt i = 0; i < Q; i++) {
116     // Setup
117     const CeedScalar J1 = J[0][i];
118     const CeedScalar J2 = J[1][i];
119 
120     const CeedScalar detJb = sqrt(J1 * J1 + J2 * J2);
121 
122     q_data_sur[0][i] = w[i] * detJb;
123     q_data_sur[1][i] = J2 / detJb;
124     q_data_sur[2][i] = -J1 / detJb;
125   }  // End of Quadrature Point Loop
126 
127   // Return
128   return 0;
129 }
130 
131 // *****************************************************************************
132 
133 #endif  // setup_geo_2d_h
134