xref: /libCEED/examples/solids/src/boundary.c (revision 5754ecac3b7d1ff97b39b25dc78c06350f2c900d)
1ccaff030SJeremy L Thompson /// @file
2ccaff030SJeremy L Thompson /// Boundary condition functions for solid mechanics example using PETSc
3ccaff030SJeremy L Thompson 
4*5754ecacSJeremy L Thompson #include "../include/boundary.h"
5ccaff030SJeremy L Thompson 
6ccaff030SJeremy L Thompson // -----------------------------------------------------------------------------
7ccaff030SJeremy L Thompson // Boundary Functions
8ccaff030SJeremy L Thompson // -----------------------------------------------------------------------------
9ccaff030SJeremy L Thompson // Note: If additional boundary conditions are added, an update is needed in
10ccaff030SJeremy L Thompson //         elasticity.h for the boundaryOptions variable.
11ccaff030SJeremy L Thompson 
12ccaff030SJeremy L Thompson // BCMMS - boundary function
13ccaff030SJeremy L Thompson // Values on all points of the mesh is set based on given solution below
14ccaff030SJeremy L Thompson // for u[0], u[1], u[2]
15d1d35e2fSjeremylt PetscErrorCode BCMMS(PetscInt dim, PetscReal load_increment,
16d1d35e2fSjeremylt                      const PetscReal coords[], PetscInt num_comp_u,
17ccaff030SJeremy L Thompson                      PetscScalar *u, void *ctx) {
18ccaff030SJeremy L Thompson   PetscScalar x = coords[0];
19ccaff030SJeremy L Thompson   PetscScalar y = coords[1];
20ccaff030SJeremy L Thompson   PetscScalar z = coords[2];
21ccaff030SJeremy L Thompson 
22ccaff030SJeremy L Thompson   PetscFunctionBeginUser;
23ccaff030SJeremy L Thompson 
24d1d35e2fSjeremylt   u[0] = exp(2*x)*sin(3*y)*cos(4*z) / 1e8 * load_increment;
25d1d35e2fSjeremylt   u[1] = exp(3*y)*sin(4*z)*cos(2*x) / 1e8 * load_increment;
26d1d35e2fSjeremylt   u[2] = exp(4*z)*sin(2*x)*cos(3*y) / 1e8 * load_increment;
27ccaff030SJeremy L Thompson 
28ccaff030SJeremy L Thompson   PetscFunctionReturn(0);
29ccaff030SJeremy L Thompson };
30ccaff030SJeremy L Thompson 
3131dc5d86Sjeremylt #ifndef M_PI
3231dc5d86Sjeremylt #  define M_PI    3.14159265358979323846
3331dc5d86Sjeremylt #endif
3431dc5d86Sjeremylt 
35d642641fSjeremylt // BCClamp - fix boundary values with affine transformation at fraction of load
36d642641fSjeremylt //   increment
37d1d35e2fSjeremylt PetscErrorCode BCClamp(PetscInt dim, PetscReal load_increment,
38d1d35e2fSjeremylt                        const PetscReal coords[], PetscInt num_comp_u,
3931dc5d86Sjeremylt                        PetscScalar *u, void *ctx) {
4031dc5d86Sjeremylt   PetscScalar x = coords[0];
4131dc5d86Sjeremylt   PetscScalar y = coords[1];
4231dc5d86Sjeremylt   PetscScalar z = coords[2];
4331dc5d86Sjeremylt   PetscScalar (*clampMax) = (PetscScalar(*))ctx;
4431dc5d86Sjeremylt 
4531dc5d86Sjeremylt   PetscFunctionBeginUser;
4672d03b64SArash Mehraban   PetscScalar
4772d03b64SArash Mehraban   // Translation vector
48d1d35e2fSjeremylt   lx = clampMax[0]*load_increment,
49d1d35e2fSjeremylt   ly = clampMax[1]*load_increment,
50d1d35e2fSjeremylt   lz = clampMax[2]*load_increment,
5172d03b64SArash Mehraban   // Normalized rotation axis
5272d03b64SArash Mehraban   kx = clampMax[3],
5372d03b64SArash Mehraban   ky = clampMax[4],
5472d03b64SArash Mehraban   kz = clampMax[5],
5572d03b64SArash Mehraban   // Rotation polynomial
5672d03b64SArash Mehraban   c_0 = clampMax[6] * M_PI,
5772d03b64SArash Mehraban   c_1 = clampMax[7] * M_PI,
5872d03b64SArash Mehraban   cx = kx * x + ky * y + kz * z,
5972d03b64SArash Mehraban   // Rotation magnitude
60d1d35e2fSjeremylt   theta = (c_0 + c_1 * cx) * load_increment;
6131dc5d86Sjeremylt   PetscScalar c = cos(theta), s = sin(theta);
6231dc5d86Sjeremylt 
6356f0bea9Sjeremylt   u[0] = lx + s*(-kz*y + ky*z) + (1-c)*(-(ky*ky+kz*kz)*x + kx*ky*y + kx*kz*z);
6456f0bea9Sjeremylt   u[1] = ly + s*(kz*x + -kx*z) + (1-c)*(kx*ky*x + -(kx*kx+kz*kz)*y + ky*kz*z);
6556f0bea9Sjeremylt   u[2] = lz + s*(-ky*x + kx*y) + (1-c)*(kx*kz*x + ky*kz*y + -(kx*kx+ky*ky)*z);
6631dc5d86Sjeremylt   PetscFunctionReturn(0);
6731dc5d86Sjeremylt };
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