Ejemplo n.º 1
0
 def __init__(self, point_coords, element_nodes, spring_constant=1.):
     self.pts = array(point_coords, copy=1)
     self.elnodes = array(element_nodes, copy=1)
     self.npts = len(self.pts)
     self.nels = len(self.elnodes)
     self.mesh = gf.Mesh('empty', 2)
     for i in range(self.npts):
         self.mesh.add_point(self.pts[i, :])
     for i in range(self.nels):
         self.mesh.add_convex(gf.GeoTrans('GT_PK(1,1)'),
                              transpose(self.pts[self.elnodes[i, :]]))
     self.fem = gf.MeshFem(self.mesh)
     self.ptdm = zeros(
         (self.npts, 2), dtype=int
     )  # point-to-dof-map i.e. rhs=self.model.rhs() then rhs[ptdm[p,i]] applies to point p and coordinate axis i
     self.fem.set_qdim(2)
     self.fem.set_classical_fem(1)
     # classic means Lagrange polynomial
     self.mim = gf.MeshIm(self.mesh, gf.Integ('IM_GAUSS1D(2)'))
     self.model = gf.Model('real')  # 2D model variable U is of real value
     self.EA = spring_constant  # stiffness k = E*A
     self.model.add_initialized_data(
         'lambda', self.EA)  # define Lame coefficients lambda and mu
     self.model.add_initialized_data('mu', 0)
     # define Lame coefficients lambda and mu
     self.model.add_fem_variable('U', self.fem)
     self.model.add_isotropic_linearized_elasticity_brick(
         self.mim, 'U', 'lambda', 'mu')
     self.nreg = 0  # how many regions are defined on the mesh
     self.fixreg = 0  # how many regions have been created for the purpose of fixing nodes
     self.loadreg = 0  # how many regions have been created for the purpose of loading nodes
     self.s_pts = zeros((self.npts, 2))  # shifted points
     self.lengths = zeros(self.nels)  # element lengths
     self.s_lengths = zeros(
         self.nels)  # element lengths in deformed geometry
     self.elong = zeros(self.nels)  # element elongation factor
     self.p_elong = zeros(self.nels)  # element percentage of elongation
     self.delta_l = zeros(self.nels)  # element length differences
     self.thescore = 0
Ejemplo n.º 2
0
nu = 0.5  # Poisson Coefficient
epsilon = 0.001  # Plate thickness
kappa = 5. / 6.  # Shear correction factor
f = -5. * pow(epsilon, 3.)  # Prescribed force on the top of the plate

variant = 0  # 0 : not reduced, 1 : with reduced integration,
# 2 : MITC reduction
quadrangles = True  # Locking free only on quadrangle for the moment
K = 1  # Degree of the finite element method
dirichlet_version = 1  # 0 = simplification, 1 = with multipliers,
# 2 = penalization
r = 1.E8  # Penalization parameter.
NX = 80  # Number of element per direction

if (quadrangles):
    m = gf.Mesh('cartesian', np.arange(0., 1. + 1. / NX, 1. / NX),
                np.arange(0., 1. + 1. / NX, 1. / NX))
else:
    m = gf.Mesh(
        'import', 'structured',
        'GT="GT_PK(2,1)";SIZES=[1,1];NOISED=0;NSUBDIV=[%d,%d];' % (NX, NX))

## Create a mesh_fem for a 2D vector field
mftheta = gf.MeshFem(m, 2)
mfu = gf.MeshFem(m, 1)
mftheta.set_classical_fem(K)
mfu.set_classical_fem(K)
mim = gf.MeshIm(m, 6)
mim_reduced = gf.MeshIm(m, 1)

## Detect the border of the mesh and assign it the boundary number 1
border = m.outer_faces()
Ejemplo n.º 3
0
import numpy as np

import getfem as gf

# parameters
file_msh = 'tripod.GiD.msh'
degree = 1
linear = False
incompressible = False  # ensure that degree > 1 when incompressible is on..
E = 1e3
Nu = 0.3
Lambda = E * Nu / ((1 + Nu) * (1 - 2 * Nu))
Mu = E / (2 * (1 + Nu))

# create a Mesh object (importing)
m = gf.Mesh('import', 'gid', file_msh)
m.set('optimize structure')

# create a MeshFem object
mfu = gf.MeshFem(m, 3)  # displacement
mfd = gf.MeshFem(m, 1)  # data
mfe = gf.MeshFem(m, 1)  # for plot von-mises
# assign the FEM
mfu.set_fem(gf.Fem('FEM_PK(3,%d)' % (degree, )))
mfd.set_fem(gf.Fem('FEM_PK(3,0)'))
mfe.set_fem(gf.Fem('FEM_PK_DISCONTINUOUS(3,%d,0.01)' % (degree, )))

# build a MeshIm object
mim = gf.MeshIm(m, gf.Integ('IM_TETRAHEDRON(5)'))

print 'nbcvs=%d, nbpts=%d, qdim=%d, fem = %s, nbdof=%d' % \
Ejemplo n.º 4
0
# You  should  have received a copy of the GNU Lesser General Public License
# along  with  this program;  if not, write to the Free Software Foundation,
# Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
#
############################################################################
"""  test export.

  This program is used to check that python-getfem is working. This is
  also a good example of use of python-getfem..

  $Id$
"""
import getfem as gf
import numpy as np

m0 = gf.Mesh('cartesian', [0, 1, 2, 3], [0, 1, 2], [-3, -2])

m0.add_convex(
    gf.GeoTrans('GT_QK(2,2)'),
    [[0, 0, 0, .4, .6, .5, 1.2, 1, 1], [0, .3, 1, 0, .5, 1, -.1, .5, 1.1],
     [0, 0, 0, 0, 0, 0, 0, 0, 0]])

m0.add_convex(
    gf.GeoTrans('GT_PK(2,2)'),
    [[2, 2, 2, 2.6, 2.5, 3.2], [0, .3, 1, 0, .5, 0], [0, 0, 0, 0, 0, 0]])

m0.add_convex(gf.GeoTrans('GT_PK(1,3)'),
              [[3.1, 2.8, 3.2, 3.7], [0, .3, .7, 1.3], [0, 0, 0, 0]])

m0.add_convex(gf.GeoTrans('GT_PRISM(3,1)'),
              [[0, 1, 0, 0, 1, 0], [0, 0, 1, 0, 0, 1], [0, 0, 0, 1, 1, 1]])
Ejemplo n.º 5
0
  $Id$
"""
import numpy as np

# Import basic modules
import getfem as gf

## Parameters
NX = 100  # Mesh parameter.
Dirichlet_with_multipliers = True  # Dirichlet condition with multipliers
# or penalization
dirichlet_coefficient = 1e10  # Penalization coefficient

# Create a simple cartesian mesh
m = gf.Mesh('regular_simplices', np.arange(0, 1 + 1. / NX, 1. / NX),
            np.arange(0, 1 + 1. / NX, 1. / NX))

# Create a MeshFem for u and rhs fields of dimension 1 (i.e. a scalar field)
mfu = gf.MeshFem(m, 1)
mfrhs = gf.MeshFem(m, 1)
# assign the P2 fem to all elements of the both MeshFem
mfu.set_fem(gf.Fem('FEM_PK(2,2)'))
mfrhs.set_fem(gf.Fem('FEM_PK(2,2)'))

#  Integration method used
mim = gf.MeshIm(m, gf.Integ('IM_TRIANGLE(4)'))

# Boundary selection
flst = m.outer_faces()
fnor = m.normal_of_faces(flst)
tleft = abs(fnor[1, :] + 1) < 1e-14
Ejemplo n.º 6
0
"""
import getfem as gf
import numpy as np
import sys

try:
    import pyvista as pv
except:
    print("\n\n** Could not load pyvista. Did you install it ?\n")
    print(
        "   ( https://docs.pyvista.org/getting-started/installation.html ) **\n\n"
    )
    sys.exit()

convex_connectivity = np.array([0, 1, 1, 2])
mesh = gf.Mesh("cartesian", [0.0, 1.0, 2.0])
pts = mesh.pts()[0]

file_name = "check_mesh_ascii.vtk"
mesh.export_to_vtk(file_name, "ascii")
unstructured_grid = pv.read(file_name)
expected = pts
actual = unstructured_grid.points[:, 0]
np.testing.assert_equal(expected, actual, "export of mesh pts is not correct.")
expected = convex_connectivity
actual = unstructured_grid.cell_connectivity
np.testing.assert_equal(expected, actual,
                        "export of mesh convex is not correct.")

file_name = "check_mesh_binary.vtk"
mesh.export_to_vtk(file_name)
Ejemplo n.º 7
0
import numpy as np

import getfem as gf

with_graphics = True
try:
    import getfem_tvtk
except:
    print(
        "\n** Could NOT import getfem_tvtk -- graphical output disabled **\n")
    import time
    time.sleep(2)
    with_graphics = False

m = gf.Mesh('import', 'gid', '../meshes/tripod.GiD.msh')
print('done!')
mfu = gf.MeshFem(m, 3)  # displacement
mfp = gf.MeshFem(m, 1)  # pressure
mfd = gf.MeshFem(m, 1)  # data
mim = gf.MeshIm(m, gf.Integ('IM_TETRAHEDRON(5)'))
degree = 2
linear = False
incompressible = False  # ensure that degree > 1 when incompressible is on..

mfu.set_fem(gf.Fem('FEM_PK(3,%d)' % (degree, )))
mfd.set_fem(gf.Fem('FEM_PK(3,0)'))
mfp.set_fem(gf.Fem('FEM_PK_DISCONTINUOUS(3,0)'))

print('nbcvs=%d, nbpts=%d, qdim=%d, fem = %s, nbdof=%d' % \
      (m.nbcvs(), m.nbpts(), mfu.qdim(), mfu.fem()[0].char(), mfu.nbdof()))
from scipy import io
from scipy.sparse import linalg
from scipy import sparse

print "parameters"

rho = 1.000e+00
Lambda = 1.000e+00
Mu = 1.000e+00

print "create a Mesh object"
d = 1.000e+00
x = 1.000e+00
y = 1.000e+00
z = 1.000e+00
m = gf.Mesh('cartesian Q1', np.arange(0., x + d, d), np.arange(0., y + d, d),
            np.arange(0., z + d, d))
m.set('optimize_structure')

print "create a MeshFem object"
mfu = gf.MeshFem(m, 3)  # displacement
print "assign the FEM"
mfu.set_fem(gf.Fem('FEM_QK(3,1)'))

print "build a MeshIm object"

mim = gf.MeshIm(m, gf.Integ('IM_HEXAHEDRON(5)'))

print "detect some boundary of the mesh"
P = m.pts()
ctop = (abs(P[0, :] - 0.) < 1e-6)
cbot = (abs(P[1, :] - 0.) < 1e-6)
Ejemplo n.º 9
0
# Import basic modules
import getfem as gf

## Parameters
NX = 20  # Mesh parameter.
N = 2
Dirichlet_with_multipliers = True  # Dirichlet condition with multipliers
# or penalization
dirichlet_coefficient = 1e10  # Penalization coefficient
using_HHO = True  # Use HHO method or standard Lagrange FEM

# Create a simple cartesian mesh
I = np.arange(0, 1 + 1. / NX, 1. / NX)
if (N == 2):
    m = gf.Mesh('regular_simplices', I, I)
elif (N == 3):
    m = gf.Mesh('regular_simplices', I, I, I)

# Meshfems
mfu = gf.MeshFem(m, 1)
mfgu = gf.MeshFem(m, N)
mfur = gf.MeshFem(m, 1)
mfrhs = gf.MeshFem(m, 1)

if (using_HHO):
    mfu.set_fem(
        gf.Fem('FEM_HHO(FEM_SIMPLEX_IPK(%d,2),FEM_SIMPLEX_CIPK(%d,2))' %
               (N, N - 1)))
    mfur.set_fem(gf.Fem('FEM_PK(%d,3)' % N))
else:
Ejemplo n.º 10
0
steps = 10
anglestep = 2 * pi / abs(z_2) / float(steps)

Lambda = 1.18e5
Mu = 0.83e5

f_coeff = 0.

disp_fem_order = 2
mult_fem_order = 1  # but discontinuous

integration_degree = 4  # 9 gauss points per quad
integration_contact_degree = 10  # 6 gauss points per face

# mesh import
m_1 = gf.Mesh('import', 'gmsh', './static_contact_planetary_1.msh')
m_2 = gf.Mesh('import', 'gmsh', './static_contact_planetary_2.msh')
m_p1 = gf.Mesh('import', 'gmsh', './static_contact_planetary_3.msh')
m_p2 = gf.Mesh('import', 'gmsh', './static_contact_planetary_4.msh')
m_p3 = gf.Mesh('import', 'gmsh', './static_contact_planetary_5.msh')

# regions definitions for boundary conditions
RG_NEUMANN_1 = 1
RG_DIRICHLET_2 = 2
RG_CONTACT_1 = 3
RG_CONTACT_2 = 4
RG_CONTACT_p1_out = 5
RG_CONTACT_p2_out = 6
RG_CONTACT_p3_out = 7
RG_CONTACT_p1_in = 8
RG_CONTACT_p2_in = 9
Ejemplo n.º 11
0
# Numerical parameters
#
h = 1  # Approximate mesh size
elements_degree = 2  # Degree of the finite element methods
gamma0 = 1. / E
# Augmentation parameter for the augmented Lagrangian

#
# Mesh generation. Meshes can also been imported from several formats.
#
mo1 = gf.MesherObject('ball', [0., 15.], 15.)
mo2 = gf.MesherObject('ball', [0., 15.], 8.)
mo3 = gf.MesherObject('set minus', mo1, mo2)

print('Meshes generation')
mesh1 = gf.Mesh('generate', mo3, h, 2)
mesh2 = gf.Mesh(
    'import', 'structured',
    'GT="GT_PK(2,1)";SIZES=[30,10];NOISED=0;NSUBDIV=[%d,%d];' %
    (int(30 / h) + 1, int(10 / h) + 1))
mesh2.translate([-15., -10.])

if (export_mesh):
    mesh1.export_to_vtk('mesh1.vtk')
    mesh2.export_to_vtk('mesh2.vtk')
    print('\nYou can view the meshes for instance with')
    print(
        'mayavi2  -d mesh1.vtk -f ExtractEdges -m Surface -d mesh2.vtk -f ExtractEdges -m Surface \n'
    )

#
Ejemplo n.º 12
0
msh_file_names.append("./LIN-HEX/HEX-1-0.msh")

# Quad-Hex 0.5mm
elements_degrees.append(2)
msh_file_names.append("./LIN-HEX/HEX-0-5.msh")

t = time.process_time()

###############################################################################
# Importing the mesh from gmsh format.
#

meshs = []

for i, msh_file_name in enumerate(msh_file_names):
    mesh = gf.Mesh("import", "gmsh", msh_file_name)
    meshs.append(mesh)

print("Time for import mesh", time.process_time() - t)
t = time.process_time()

###############################################################################
# Definition of finite elements methods and integration method
#

mfus = []
mfds = []
mims = []

for elements_degree, mesh in zip(elements_degrees, meshs):
Ejemplo n.º 13
0
#
############################################################################
"""  test levelset.

  This program is used to check that python-getfem is working. This is
  also a good example of use of python-getfem..

  $Id$
"""
import getfem as gf
import numpy as np
from scipy import rand

eps = 1.0/10

m = gf.Mesh('regular_simplices', np.arange(-1,1+eps,eps), np.arange(-1,1+eps,eps), 'degree', 2, 'noised')
#m = gf.Mesh('cartesian', np.arange(-1,1+eps,eps), np.arange(-1,1+eps,eps))

ls1 = gf.LevelSet(m, 2, 'y', 'x')
#ls1 = gf.LevelSet(m, 2, 'sqr(x) + sqr(y) - sqr(0.7)', 'x-.4')
#ls1 = gf.LevelSet(m, 2, 'x + y - 0.2') #, 'x-5')
#ls1 = gf.LevelSet(m, 2, 'x + y - 0.2', 'x-5')
#ls2 = gf.LevelSet(m, 2, '0.6*sqr(x) + sqr(y-0.1) - sqr(0.6)');
#ls3 = gf.LevelSet(m, 4, 'sqr(x) + sqr(y+.08) - sqr(0.05)');
ls2 = gf.LevelSet(m, 2, 'y+0.1', 'x')
ls3 = gf.LevelSet(m, 2, 'y-0.1', 'x')

mls = gf.MeshLevelSet(m)

mls.add(ls1)
if True:
Ejemplo n.º 14
0
def import_fem(sico):
    """ Build a mesh object using getfem.
    
    We use getfem++ to build the finite element model and
    to fill in the operators required by siconos:
    - the mass matrix (Mass)
    - the stiffness matrix (Stiff)
    - the matrix that links global coordinates and local coord. at contact points (H)
    
    """
    ############################
    # The geometry and the mesh
    ############################
    dimX = 10.01
    dimY = 10.01
    dimZ = 3.01
    stepX = 1.0
    stepY = 1.0
    stepZ = 1.0
    x = np.arange(0, dimX, stepX)
    y = np.arange(0, dimY, stepY)
    z = np.arange(0, dimZ, stepZ)
    m = gf.Mesh('regular simplices', x, y, z)
    m.set('optimize_structure')
    # Export the mesh to vtk
    m.export_to_vtk("BlockMesh.vtk")

    # Create MeshFem objects
    # (i.e. assign elements onto the mesh for each variable)
    mfu = gf.MeshFem(m, 3)  # displacement
    mfd = gf.MeshFem(m, 1)  # data
    mff = gf.MeshFem(m, 1)  # for plot von-mises
    # assign the FEM
    mfu.set_fem(gf.Fem('FEM_PK(3,1)'))
    mfd.set_fem(gf.Fem('FEM_PK(3,0)'))
    mff.set_fem(gf.Fem('FEM_PK_DISCONTINUOUS(3,1,0.01)'))
    # mfu.export_to_vtk("BlockMeshDispl.vtk")

    # Set the integration method
    mim = gf.MeshIm(m, gf.Integ('IM_TETRAHEDRON(5)'))

    # Summary
    print(' ==================================== \n Mesh details: ')
    print(' Problem dimension:', mfu.qdim(), '\n Number of elements: ',
          m.nbcvs(), '\n Number of nodes: ', m.nbpts())
    print(' Number of dof: ', mfu.nbdof(), '\n Element type: ',
          mfu.fem()[0].char())
    print(' ====================================')

    ###########################
    # Set the parameters
    # for the constitutive law
    ###########################
    E = 1e3  # Young modulus
    Nu = 0.3  # Poisson coef.
    # Lame coeff.
    Lambda = E * Nu / ((1 + Nu) * (1 - 2 * Nu))
    Mu = E / (2 * (1 + Nu))
    # Density
    Rho = 1.0  #7.800
    Gravity = -9.81
    ############################
    # Boundaries detection
    ############################
    allPoints = m.pts()
    # Bottom points and faces
    cbot = (abs(allPoints[2, :]) < 1e-6)
    pidbot = np.compress(cbot, list(range(0, m.nbpts())))
    fbot = m.faces_from_pid(pidbot)
    BOTTOM = 1
    m.set_region(BOTTOM, fbot)
    # Top points and faces
    ctop = (abs(allPoints[2, :]) > dimZ - stepZ)
    pidtop = np.compress(ctop, list(range(0, m.nbpts())))
    ftop = m.faces_from_pid(pidtop)
    TOP = 2
    m.set_region(TOP, ftop)
    # Top-Left points and faces
    cleft = (abs(allPoints[1, :]) < 1e-6)
    clefttop = cleft * ctop
    pidlefttop = np.compress(clefttop, list(range(0, m.nbpts())))
    flefttop = m.faces_from_pid(pidlefttop)
    pidleft = np.compress(cleft, list(range(0, m.nbpts())))
    fleft = m.faces_from_pid(pidleft)
    LEFTTOP = 3
    m.set_region(LEFTTOP, flefttop)
    LEFT = 4
    m.set_region(LEFT, fleft)

    # Create a model
    md = gf.Model('real')
    md.add_fem_variable('u', mfu)
    md.add_initialized_data('lambda', Lambda)
    md.add_initialized_data('mu', Mu)
    md.add_initialized_data('source_term', [0, 0, -100])
    md.add_initialized_data('push', [0, 100, 0])
    md.add_initialized_data('rho', Rho)
    md.add_initialized_data('gravity', Gravity)
    #    Weight = np.zeros(mfu.nbdof())
    ##    Weight = []
    md.add_initialized_data('weight', [0, 0, Rho * Gravity])
    md.add_isotropic_linearized_elasticity_brick(mim, 'u', 'lambda', 'mu')
    #md.add_source_term_brick(mim,'u','source_term',TOP)
    #md.add_source_term_brick(mim,'u','push',LEFT)
    md.add_source_term_brick(mim, 'u', 'weight')
    #md.add_Dirichlet_condition_with_multipliers(mim,'u',mfu,BOTTOM)

    md.assembly()
    sico.Stiff = md.tangent_matrix()
    sico.RHS = md.rhs()
    sico.q0 = md.variable('u')
    md2 = gf.Model('real')
    md2.add_fem_variable('u', mfu)
    md2.add_initialized_data('rho', Rho)
    md2.add_mass_brick(mim, 'u', 'rho')
    md2.assembly()
    sico.Mass = md2.tangent_matrix()
    sico.nbdof = mfu.nbdof()
    sico.mfu = mfu
    sico.mesh = m
    sico.pos = np.zeros(sico.nbdof)

    sico.pos[0:sico.nbdof:3] = m.pts()[0, :]
    sico.pos[1:sico.nbdof:3] = m.pts()[1, :]
    sico.pos[2:sico.nbdof:3] = m.pts()[2, :]
    sico.K0 = np.dot(sico.Stiff.full(), sico.pos)
    sico.bot = pidbot
    # running solve...
    #md.solve()

    # post-processing
    #VM=md.compute_isotropic_linearized_Von_Mises_or_Tresca('u','lambda','mu',mff)
    # extracted solution
    #U = md.variable('u')
    # export U and VM in a pos file
    #sl = gf.Slice(('boundary',),mfu,1)
    #sl.export_to_vtk('toto.vtk', mfu, U, 'Displacement', mff, VM, 'Von Mises Stress')

    # H-Matrix
    fillH(pidbot, sico, mfu.nbdof())

    return md
Ejemplo n.º 15
0
def import_fem2(sico):
    """ Build a mesh object using getfem.
    
    We use getfem++ to build the finite element model and
    to fill in the operators required by siconos:
    - the mass matrix (Mass)
    - the stiffness matrix (Stiff)
    - the matrix that links global coordinates and local coord. at contact points (H)
    
    """
    ############################
    # The geometry and the mesh
    ############################
    dimX = 10.01
    dimY = 10.01
    dimZ = 10.01
    stepX = 1.0
    stepY = 1.0
    stepZ = 1.0
    x = np.arange(0, dimX, stepX)
    y = np.arange(0, dimY, stepY)
    z = np.arange(0, dimZ, stepZ)
    m = gf.Mesh('regular simplices', x, y, z)
    m.set('optimize_structure')
    # Export the mesh to vtk
    m.export_to_vtk("BlockMesh.vtk")

    # Create MeshFem objects
    # (i.e. assign elements onto the mesh for each variable)
    mfu = gf.MeshFem(m, 3)  # displacement
    mfd = gf.MeshFem(m, 1)  # data
    mff = gf.MeshFem(m, 1)  # for plot von-mises
    # assign the FEM
    mfu.set_fem(gf.Fem('FEM_PK(3,1)'))
    mfd.set_fem(gf.Fem('FEM_PK(3,0)'))
    mff.set_fem(gf.Fem('FEM_PK_DISCONTINUOUS(3,1,0.01)'))
    # mfu.export_to_vtk("BlockMeshDispl.vtk")

    # Set the integration method
    mim = gf.MeshIm(m, gf.Integ('IM_TETRAHEDRON(5)'))

    # Summary
    print(' ==================================== \n Mesh details: ')
    print(' Problem dimension:', mfu.qdim(), '\n Number of elements: ',
          m.nbcvs(), '\n Number of nodes: ', m.nbpts())
    print(' Number of dof: ', mfu.nbdof(), '\n Element type: ',
          mfu.fem()[0].char())
    print(' ====================================')

    ###########################
    # Set the parameters
    # for the constitutive law
    ###########################
    E = 1e3  # Young modulus
    Nu = 0.3  # Poisson coef.
    # Lame coeff.
    Lambda = E * Nu / ((1 + Nu) * (1 - 2 * Nu))
    Mu = E / (2 * (1 + Nu))
    # Density
    Rho = 7800
    ############################
    # Boundaries detection
    ############################
    allPoints = m.pts()
    # Bottom points and faces
    cbot = (abs(allPoints[2, :]) < 1e-6)
    pidbot = np.compress(cbot, list(range(0, m.nbpts())))
    fbot = m.faces_from_pid(pidbot)
    BOTTOM = 1
    m.set_region(BOTTOM, fbot)
    # Top points and faces
    ctop = (abs(allPoints[2, :]) > dimZ - stepZ)
    pidtop = np.compress(ctop, list(range(0, m.nbpts())))
    ftop = m.faces_from_pid(pidtop)
    TOP = 2
    m.set_region(TOP, ftop)
    # Top-Left points and faces
    cleft = (abs(allPoints[1, :]) < 1e-6)
    clefttop = cleft * ctop
    pidlefttop = np.compress(clefttop, list(range(0, m.nbpts())))
    flefttop = m.faces_from_pid(pidlefttop)
    pidleft = np.compress(cleft, list(range(0, m.nbpts())))
    fleft = m.faces_from_pid(pidleft)
    LEFTTOP = 3
    m.set_region(LEFTTOP, flefttop)
    LEFT = 4
    m.set_region(LEFT, fleft)

    ############################
    # Assembly
    ############################
    nbd = mfd.nbdof()
    # Stiffness matrix
    sico.Stiff = gf.asm_linear_elasticity(mim, mfu, mfd,
                                          np.repeat([Lambda], nbd),
                                          np.repeat([Mu], nbd))
    # Mass matrix
    sico.Mass = Rho * gf.asm_mass_matrix(mim, mfu)
    # Right-hand side
    Ftop = gf.asm_boundary_source(TOP, mim, mfu, mfd,
                                  np.repeat([[0], [0], [-1]], nbd, 1))
    Fleft = gf.asm_boundary_source(LEFT, mim, mfu, mfd,
                                   np.repeat([[0], [10], [0]], nbd, 1))
    sico.RHS = Ftop + Fleft

    sico.nbdof = mfu.nbdof()
    sico.q0 = mfu.basic_dof_from_cvid()

    sico.bot = pidbot

    # H-Matrix
    fillH(pidbot, sico, mfu.nbdof())
    return m
Ejemplo n.º 16
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alpha_crack = 0.01  # [N/mm/s/K] Heat transfer coefficient
mR = 287e3 * 5e-9  # [N*mm/K] --> 287000 [N*mm/kg/K] * mass [kg]
room_temp = 30.  # [C] temperature on one side of the block
jump_temp = 100.  # [C] temperature jump between the two sides

# Mesh definition:
L = 40.  # [mm]
l = 10.  # [mm]
ny = 10  # Number of elements in each direction
quad = True  # quad mesh or triangle one

h = l / ny
nx = np.floor(L / h)

if (quad):
    m = gf.Mesh("cartesian", -L / 2. + np.arange(nx + 1) * h,
                -l / 2 + np.arange(ny + 1) * h)
else:
    m = gf.Mesh("regular_simplices", -L / 2 + np.arange(nx + 1) * h,
                -l / 2 + np.arange(ny + 1) * h)

LEFT_RG = 101
RIGHT_RG = 102
BOTTOM_RG = 103
TOP_RG = 104
fleft = m.outer_faces_with_direction([-1., 0.], 0.5)
fright = m.outer_faces_with_direction([1., 0.], 0.5)
fbottom = m.outer_faces_with_direction([0., -1.], 0.5)
ftop = m.outer_faces_with_direction([0., 1.], 0.5)
m.set_region(LEFT_RG, fleft)
m.set_region(RIGHT_RG, fright)
m.set_region(BOTTOM_RG, fbottom)
Ejemplo n.º 17
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# auxiliary constants
B_BOUNDARY = 4
T_BOUNDARY = 6
TB_BOUNDARY = 7

NX_seed1 = np.linspace(-1, 0, NX / 3 + 1)
NX_seed2 = np.linspace(0, 1, (NX - NX / 3) + 1)[1:]
NY_seed = np.linspace(-1, 1, NY + 1)
X_seed1 = LX / 2 * (0.2 * NX_seed1 +
                    0.8 * np.sign(NX_seed1) * np.power(np.abs(NX_seed1), 1.5))
X_seed2 = LX / 2 * (0.6 * NX_seed2 +
                    0.4 * np.sign(NX_seed2) * np.power(np.abs(NX_seed2), 1.5))
X_seed = np.concatenate((X_seed1, X_seed2))
Y_seed = LY / 2 * (0.2 * NY_seed +
                   0.8 * np.sign(NY_seed) * np.power(np.abs(NY_seed), 1.5))
m1 = gf.Mesh("cartesian", X_seed, Y_seed[0:NY / 2 + 1])
m2 = gf.Mesh("cartesian", X_seed, Y_seed[NY / 2:])
gap = 1e-5
pts = m1.pts()
for i in range(pts.shape[1]):
    if pts[0, i] < -1e-10:
        pts[1, i] -= gap / 2 * (1 + pts[1, i] / (LY / 2))
m1.set_pts(pts)
pts = m2.pts()
for i in range(pts.shape[1]):
    if pts[0, i] < -1e-10:
        pts[1, i] += gap / 2 * (1 - pts[1, i] / (LY / 2))
m2.set_pts(pts)
mesh = m1
mesh.merge(m2)
N = mesh.dim()
# coding: utf-8
import getfem as gf
import numpy as np
m = gf.Mesh('cartesian', np.arange(0.0, 10.0, 1.0))
print m
mfu = gf.MeshFem(m,1)
mfu.set_fem(gf.Fem('FEM_PK(1,1)'))
mim = gf.MeshIm(m, gf.Integ('IM_GAUSS1D(1)'))
mfd = gf.MeshFem(m, 1)
mfd.set_fem(gf.Fem('FEM_PK(1,1)'))
nbd = mfd.nbdof()
Lambda = 1.0; Mu = 1.0
K = gf.asm_linear_elasticity(mim, mfu, mfd, np.repeat([Lambda], nbd), np.repeat([Mu], nbd))
K.full()
print 'Lambda = ', Lambda
print 'Mu     = ', Mu
print K.full()
print '2*Mu+Lambda = ', 2*Mu+Lambda
Ejemplo n.º 19
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# define constants
NEUMANN_BOUNDARY = 1
NEUMANN_BOUNDARY_NO_LOAD = 2
DIRICHLET_BOUNDARY = 3
OMEGA = 4
INNER_FACES=6

degree = 1

make_check=('srcdir' in os.environ);
filename='../meshes/mixed_mesh.gmf'
if (make_check):
    filename=os.environ['srcdir']+'/'+filename

m = gf.Mesh('load', filename)

#--------------- boundary condtions
# detect some boundary of the mesh

face_left = m.outer_faces_with_direction([0, 0., -1.0], 0.01)
face_right = m.outer_faces_with_direction([0., 0., 1.0], 0.01)

face_top = m.outer_faces_with_direction([0., 1., 0], 0.01)
face_bottom = m.outer_faces_with_direction([0., -1., 0], 0.01)
face_top1 = m.outer_faces_with_direction([1., 0., 0], 0.01)
face_bottom1 = m.outer_faces_with_direction([-1., 0., 0], 0.01)
face_top_bottom =  np.append(np.append(np.append(face_top,face_bottom,axis=1),face_top1 , axis=1), face_bottom1, axis=1)

# create boundary regions
m.set_region(NEUMANN_BOUNDARY,face_right)
Ejemplo n.º 20
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"""  Plate problem test.

  This program is used to check that python-getfem is working. This is
  also a good example of use of GetFEM++.

  $Id$
"""
import numpy as np

import getfem as gf

NX = 10.0
thickness = 0.01
f = -5. * pow(thickness, 3.)

m = gf.Mesh('regular simplices', np.arange(0, 1.01, 1 / NX),
            np.arange(0, 1.01, 1 / NX))
mfu3 = gf.MeshFem(m, 1)
mfth = gf.MeshFem(m, 2)
mfd = gf.MeshFem(m, 1)

mfu3.set_fem(gf.Fem('FEM_PK(2,1)'))
mfth.set_fem(gf.Fem('FEM_PK(2,2)'))
mfd.set_fem(gf.Fem('FEM_PK(2,2)'))

mim = gf.MeshIm(m, gf.Integ('IM_TRIANGLE(5)'))

#get the list of faces whose normal is [-1,0]
flst = m.outer_faces()
fnor = m.normal_of_faces(flst)
fleft = np.compress(abs(fnor[1, :] + 1) < 1e-14, flst, axis=1)
fright = np.compress(abs(fnor[1, :] - 1) < 1e-14, flst, axis=1)
Ejemplo n.º 21
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import getfem as gf
import numpy as np

with_graphics = True
try:
    import getfem_tvtk
except:
    print "\n** Could NOT import getfem_tvtk -- graphical output disabled **\n"
    import time
    time.sleep(2)
    with_graphics = False

L = 100
H = 20

m = gf.Mesh('triangles grid', np.arange(0, L + 0.01, 4),
            np.arange(0, H + 0.01, 2))

mim = gf.MeshIm(m, gf.Integ('IM_TRIANGLE(6)'))
mfu = gf.MeshFem(m, 2)
mfsigma = gf.MeshFem(m, 4)
mfd = gf.MeshFem(m)
mf0 = gf.MeshFem(m)
mfdu = gf.MeshFem(m)

mfu.set_fem(gf.Fem('FEM_PK(2,1)'))
mfsigma.set_fem(gf.Fem('FEM_PK_DISCONTINUOUS(2,1)'))
mfd.set_fem(gf.Fem('FEM_PK(2,1)'))
mf0.set_fem(gf.Fem('FEM_PK(2,0)'))
mfdu.set_fem(gf.Fem('FEM_PK_DISCONTINUOUS(2,1)'))

Lambda = 121150
Ejemplo n.º 22
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alpha = 1.               # Alpha coefficient for "sliding velocity"
f_coeff = 0.             # Friction coefficient
release_dist = 5.


#------------------------------------
clambda1 = E1*nu1 / ((1+nu1)*(1-2*nu1))
cmu1 = E1 / (2*(1+nu1))
clambda2 = E2*nu2 / ((1+nu2)*(1-2*nu2))
cmu2 = E2 / (2*(1+nu2))
clambda = E*nu / ((1+nu)*(1-2*nu))
cmu = E / (2*(1+nu))


mesh_R = gf.Mesh('import', 'structured',
                 'GT="%s";ORG=[-1,-1];SIZES=[2,1];NSUBDIV=[%i,%i]'
                 % (geotrans_R, Ncirc, Nt1+Nt2))
mesh_B = gf.Mesh('import', 'structured',
                 'GT="%s";ORG=[%f,%f];SIZES=[%f,%f];NSUBDIV=[%i,%i]'
                 % (geotrans_B, -lx/2, -ly, lx, ly, Nx, Ny))

N = mesh_R.dim()

CONTACT_BOUNDARY_R = 1
DIRICHLET_BOUNDARY_R = 3
CONTACT_BOUNDARY_B = 5
DIRICHLET_BOUNDARY_B = 7
RING1 = 11
RING2 = 12

outer_R = mesh_R.outer_faces()
Ejemplo n.º 23
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B_BOUNDARY = 5
T_BOUNDARY = 6
DIR_BOUNDARY = 7
OUT_BOUNDARY = 8

xmin = -L / 2
ymin = -H / 2
dx = L
dy = H
if symmetric:
    xmin = 0.
    ymin = 0.
    dx = L / 2
    dy = H / 2
mesh = gf.Mesh(
    'import', 'structured',
    'GT="%s";ORG=[%f,%f];SIZES=[%f,%f];NSUBDIV=[%i,%i]' %
    (geotrans, xmin, ymin, dx, dy, N_L, N_H))

N = mesh.dim()

outer_faces = mesh.outer_faces()
outer_normals = mesh.normal_of_faces(outer_faces)
left_boundary = outer_faces[:, np.nonzero(outer_normals[0] < -0.95)[0]]
right_boundary = outer_faces[:, np.nonzero(outer_normals[0] > 0.95)[0]]
bottom_boundary = outer_faces[:, np.nonzero(outer_normals[1] < -0.95)[0]]
top_boundary = outer_faces[:, np.nonzero(outer_normals[1] > 0.95)[0]]
mesh.set_region(L_BOUNDARY, left_boundary)
mesh.set_region(R_BOUNDARY, right_boundary)
mesh.set_region(B_BOUNDARY, bottom_boundary)
mesh.set_region(T_BOUNDARY, top_boundary)
Ejemplo n.º 24
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# ===============================
# Build FEM using getfem
# ===============================

# ==== The geometry and the mesh ====
dimX = 10.01
dimY = 10.01
dimZ = 3.01
stepX = 2.0
stepY = 2.0
stepZ = 1.5
x = np.arange(0, dimX, stepX)
y = np.arange(0, dimY, stepY)
z = np.arange(0, dimZ, stepZ)
m = gf.Mesh('regular simplices', x, y, z)
m.set('optimize_structure')
# Export the mesh to vtk
m.export_to_vtk("BlockMesh.vtk")

# Create MeshFem objects
# (i.e. assign elements onto the mesh for each variable)
mfu = gf.MeshFem(m, 3)  # displacement
mff = gf.MeshFem(m, 1)  # for plot von-mises
# assign the FEM
mfu.set_fem(gf.Fem('FEM_PK(3,1)'))
mff.set_fem(gf.Fem('FEM_PK_DISCONTINUOUS(3,1,0.01)'))
# mfu.export_to_vtk("BlockMeshDispl.vtk")

# ==== Set the integration method ====
mim = gf.MeshIm(m, gf.Integ('IM_TETRAHEDRON(5)'))
Ejemplo n.º 25
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# or penalization
dirichlet_coefficient = 1e10  # Penalization coefficient
export_mesh = True  # Draw the mesh after mesh generation or not

# Create a mesh
mo1 = gf.MesherObject('rectangle', [0., 50.], [100., 100.])
mo2 = gf.MesherObject('rectangle', [50., 0.], [100., 100.])
mo3 = gf.MesherObject('union', mo1, mo2)
mo4 = gf.MesherObject('ball', [25., 75], 8.)
mo5 = gf.MesherObject('ball', [75., 25.], 8.)
mo6 = gf.MesherObject('ball', [75., 75.], 8.)
mo7 = gf.MesherObject('union', mo4, mo5, mo6)
mo = gf.MesherObject('set minus', mo3, mo7)

gf.util('trace level', 2)  # No trace for mesh generation
mesh = gf.Mesh('generate', mo, h, 3)

#
# Boundary selection
#
fb1 = mesh.outer_faces_with_direction([-1., 0.], 0.01)  # Left   (Dirichlet)
fb2 = mesh.outer_faces_with_direction([0., -1.], 0.01)  # Bottom (Neumann)
fb3 = mesh.outer_faces_in_box([-1., 10.], [101., 101.])
fb4 = mesh.outer_faces_in_box([10., -1.], [101., 101.])
LEFT_BOUND = 1
BOTTOM_BOUND = 2
AUX_BOUND1 = 3
AUX_BOUND2 = 4
mesh.set_region(LEFT_BOUND, fb1)
mesh.set_region(BOTTOM_BOUND, fb2)
mesh.set_region(AUX_BOUND1, fb3)
Ejemplo n.º 26
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dirichlet_version = 2          # 1 = simplification, 2 = penalisation
test_tangent_matrix = False    # Test or not tangent system validity
incompressible = False;        # Incompressibility option
explicit_potential = False;    # Elasticity law with explicit potential

# lawname = 'Ciarlet Geymonat'
# params = [1.,1.,0.25]
lawname = 'SaintVenant Kirchhoff'
params = [1.,1.]
if (incompressible):
    lawname = 'Incompressible Mooney Rivlin'
    params = [1.,1.]

N1 = 2; N2 = 4; h = 20.; DX = 1./N1; DY = (1.*h)/N2;
m = gf.Mesh('cartesian', np.arange(-0.5, 0.5+DX,DX), np.arange(0., h+DY,DY),
            np.arange(-1.5, 1.5+3*DX,3*DX))
mfu  = gf.MeshFem(m, 3)            # mesh-fem supporting a 3D-vector field
mfdu = gf.MeshFem(m,1)
# The mesh_im stores the integration methods for each tetrahedron
mim = gf.MeshIm(m, gf.Integ('IM_GAUSS_PARALLELEPIPED(3,4)'))
# We choose a P2 fem for the main unknown
mfu.set_fem(gf.Fem('FEM_QK(3,2)'))

if (dirichlet_version == 1):
  mfd = mfu;
else:
  mfd = gf.MeshFem(m,1)
  mfd.set_fem(gf.Fem('FEM_QK(3,1)'))

# The P2 fem is not derivable across elements, hence we use a discontinuous
# fem for the derivative of U.
    #% Draw solution each NBDRAW iterations

hole_radius = max(0.03, 2. / NY)
#% Hole radius for topological optimization
ls_degree = 1
#% Degree of the level-set. Should be one for the moment.
DEBUG = False
if DEBUG:
    NG = 3
else:
    NG = 2

#% Mesh definition
#% m=gfMesh('cartesian', -1:(1/NY):1, -.5:(1/NY):.5);
if (N == 2):
    m = gf.Mesh('regular simplices', np.linspace(-1., 1., NY),
                np.linspace(-.5, .5, NY))
else:
    m = gf.Mesh('regular simplices', np.linspace(-1., 1., NY),
                np.linspace(-.5, .5, NY), np.linspace(-.5, .5, NY))
pts = m.pts()

#% Find the boundary GammaD and GammaN
pidleft = np.compress((abs(pts[0, :] + 1.0) < 1e-7), list(range(0, m.nbpts())))
fidleft = m.faces_from_pid(pidleft)
normals = m.normal_of_faces(fidleft)
fidleft = fidleft[:, abs(normals[0, :] + 1.0) < 1e-3]
GAMMAD = 2
m.set_region(GAMMAD, fidleft)

pidright = np.compress((abs(pts[0, :] - 1.0) < 1e-7), list(range(0,
                                                                 m.nbpts())))
Ejemplo n.º 28
0
dt = 0.01
T = 3.
nu = 0.01

p_in_str = "np.sin(3*{0})"

#Mesh and MeshRegion
IN_RG = 1
OUT_RG = 2
INOUT_RG = 3
WALL_RG = 4

geotrans = "GT_QK(2,2)"
m = gf.Mesh("import", "structured",
            "GT='%s';ORG=[%f,%f];SIZES=[%f,%f];NSUBDIV=[%i,%i]"
            % (geotrans, 0, H2, W1, H1, NW1, NH1))
m.merge(gf.Mesh("import", "structured",
                "GT='%s';ORG=[%f,%f];SIZES=[%f,%f];NSUBDIV=[%i,%i]"
                % (geotrans, 0, 0, W1, H2, NW1, NH2)))
m.merge(gf.Mesh("import", "structured",
                "GT='%s';ORG=[%f,%f];SIZES=[%f,%f];NSUBDIV=[%i,%i]"
                % (geotrans, W1, 0, W2, H2, NW2, NH2)))
m.optimize_structure()

l_rg = m.outer_faces_with_direction([-1,0], np.pi/180)
b_rg = m.outer_faces_with_direction([0,-1], np.pi/180)
r_rg = m.outer_faces_with_direction([1,0], np.pi/180)
t_rg = m.outer_faces_with_direction([0,1], np.pi/180)
in_rg = m.outer_faces_in_box([-1e-6,H1+H2-1e-6],[W1+1e-6,H1+H2+1e-6])
out_rg = m.outer_faces_in_box([W1+W2-1e-6,-1e-6],[W1+W2+1e-6,H2+1e-6])
Ejemplo n.º 29
0
            u = 1. / 2. - x / 2.
            dxu = -1. / 2.
            dtu = 0
        elif zone == 4:
            u = 1. / 2. - x / 2.
            dxu = -1. / 2.
            dtu = 0.
    return (u if (d == 0) else (dxu if (d == 1) else dtu))


def linsolve(M, B):  # Call Superlu to solve a sparse linear system
    return (((gf.linsolve_superlu(M, B))[0]).T)[0]


# Mesh
m = gf.Mesh('cartesian', np.arange(0, 1 + 1. / NX, 1. / NX))

# Selection of the contact and Dirichlet boundaries
GAMMAC = 1
GAMMAD = 2
border = m.outer_faces()
normals = m.normal_of_faces(border)
contact_boundary = border[:, np.nonzero(normals[0] < -0.01)[0]]
m.set_region(GAMMAC, contact_boundary)
contact_boundary = border[:, np.nonzero(normals[0] > 0.01)[0]]
m.set_region(GAMMAD, contact_boundary)

# Finite element methods
mfu = gf.MeshFem(m)
mfu.set_classical_fem(
    u_degree)  # Assumed to be a Lagrange FEM in the following
Ejemplo n.º 30
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############################################################################
"""  Test of the assembly on the direct product of two domains.

  This program is used to check that Python-GetFEM interface, and more
  generally GetFEM are working. It focuses on testing some operations
  of the high generic assembly language.

  $Id$
"""
import numpy as np
import getfem as gf
import os

NX = 4

m1 = gf.Mesh('cartesian', np.arange(0, 1 + 1. / NX,
                                    1. / NX))  # Structured 1D mesh
mfu1 = gf.MeshFem(m1, 1)
mfu1.set_fem(gf.Fem('FEM_PK(1,1)'))
mim1 = gf.MeshIm(m1, gf.Integ('IM_GAUSS1D(4)'))
U1 = mfu1.eval('x')

m2 = gf.Mesh('triangles grid', np.arange(0, 1 + 1. / NX, 1. / NX),
             np.arange(0, 1 + 1. / NX, 1. / NX))  # Structured 2D mesh
mfu2 = gf.MeshFem(m2, 1)
mfu2.set_fem(gf.Fem('FEM_PK(2,1)'))
mim2 = gf.MeshIm(m2, gf.Integ('IM_TRIANGLE(4)'))
U2 = mfu2.eval('x+y')

md = gf.Model('real')

md.add_fem_variable('u1', mfu1)