xref: /libCEED/examples/solids/qfunctions/traction-boundary.h (revision 3d8e882215d238700cdceb37404f76ca7fa24eaa)
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 for solid mechanics example using PETSc
10 
11 #ifndef TRACTION_BOUNDARY_H
12 #define TRACTION_BOUNDARY_H
13 
14 // -----------------------------------------------------------------------------
15 // This QFunction computes the surface integral of the user traction vector on
16 //   the constrained faces.
17 //
18 // Reference (parent) 2D coordinates: X
19 // Physical (current) 3D coordinates: x
20 // Change of coordinate matrix:
21 //   dxdX_{i,j} = dx_i/dX_j (indicial notation) [3 * 2]
22 //
23 // (J1,J2,J3) is given by the cross product of the columns of dxdX_{i,j}
24 //
25 // detJb is the magnitude of (J1,J2,J3)
26 //
27 // Computed:
28 //   t * (w detJb)
29 //
30 // -----------------------------------------------------------------------------
31 CEED_QFUNCTION(SetupTractionBCs)(void *ctx, CeedInt Q,
32                                  const CeedScalar *const *in, CeedScalar *const *out) {
33   // *INDENT-OFF*
34   // Inputs
35   const CeedScalar(*J)[3][CEED_Q_VLA] = (const CeedScalar(*)[3][CEED_Q_VLA])in[0],
36         (*w) = in[1];
37   // Outputs
38   CeedScalar(*v)[CEED_Q_VLA] = (CeedScalar(*)[CEED_Q_VLA])out[0];
39   // *INDENT-ON*
40 
41   // User stress tensor
42   const CeedScalar (*traction) = (const CeedScalar(*))ctx;
43 
44   CeedPragmaSIMD
45   // Quadrature Point Loop
46   for (CeedInt i = 0; i < Q; i++) {
47     // Setup
48     // *INDENT-OFF*
49     const CeedScalar dxdX[3][2] = {{J[0][0][i],
50                                     J[1][0][i]},
51                                    {J[0][1][i],
52                                     J[1][1][i]},
53                                    {J[0][2][i],
54                                     J[1][2][i]}};
55     // *INDENT-ON*
56     // J1, J2, and J3 are given by the cross product of the columns of dxdX
57     const CeedScalar J1 = dxdX[1][0] * dxdX[2][1] - dxdX[2][0] * dxdX[1][1];
58     const CeedScalar J2 = dxdX[2][0] * dxdX[0][1] - dxdX[0][0] * dxdX[2][1];
59     const CeedScalar J3 = dxdX[0][0] * dxdX[1][1] - dxdX[1][0] * dxdX[0][1];
60 
61     // Qdata
62     // -- Interp-to-Interp q_data
63     CeedScalar wdetJb = w[i] * sqrt(J1 * J1 + J2 * J2 + J3 * J3);
64 
65     // Traction surface integral
66     for (CeedInt j = 0; j < 3; j++)
67       v[j][i] = traction[j] * wdetJb;
68 
69   } // End of Quadrature Point Loop
70 
71   // Return
72   return 0;
73 }
74 // -----------------------------------------------------------------------------
75 
76 #endif // End of TRACTION_BOUNDARY_H
77