Exemplo n.º 1
0
def construct_A_from_mesh_functions(dim, A_expr, mesh):

    if dim == 2:
        a01 = MeshFunction("double", mesh, dim)
        a11 = MeshFunction("double", mesh, dim)

    A1 = A_expr[0]
    A2 = A_expr[1]

    a00 = MeshFunction("double", mesh, dim)

    for cell in cells(mesh):
        if cell.midpoint().x() < 0.5:
            if dim == 2:
                a00[cell] = A1[0][0]
                a11[cell] = A1[1][1]
                a01[cell] = A1[0][1]
        else:
            if dim == 2:
                a00[cell] = A2[0][0]
                a11[cell] = A2[1][1]
                a01[cell] = A2[0][1]

    # Code for C++ evaluation of conductivity
    conductivity_code = """

    class Conductivity : public Expression
    {
    public:

      // Create expression with 3 components
      Conductivity() : Expression(3) {}

      // Function for evaluating expression on each cell
      void eval(Array<double>& values, const Array<double>& x, const ufc::cell& cell) const
      {
        const uint D = cell.topological_dimension;
        const uint cell_index = cell.index;
        values[0] = (*a00)[cell_index];
        values[1] = (*a01)[cell_index];
        values[2] = (*a11)[cell_index];
      }

      // The data stored in mesh functions
      std::shared_ptr<MeshFunction<double> > a00;
      std::shared_ptr<MeshFunction<double> > a01;
      std::shared_ptr<MeshFunction<double> > a11;

    };
    """

    a = Expression(cppcode=conductivity_code)
    a.a00 = a00
    a.a01 = a01
    a.a11 = a11
    A = as_matrix(((a[0], a[1]), (a[1], a[2])))

    return A
Exemplo n.º 2
0
    def __init__(self, args, tc, metadata):
        self.has_analytic_solution = False
        self.problem_code = 'FACB'
        super(Problem, self).__init__(args, tc, metadata)

        self.name = 'test on real mesh'
        self.status_functional_str = 'not selected'

        # input parameters
        self.factor = args.factor
        self.scale_factor.append(self.factor)

        self.nu = 0.001 * args.nufactor  # kinematic viscosity

        # Import gmsh mesh
        self.compatible_meshes = ['bench3D_1', 'bench3D_2', 'bench3D_3']
        if args.mesh not in self.compatible_meshes:
            exit('Bad mesh, should be some from %s' %
                 str(self.compatible_meshes))

        self.mesh = Mesh("meshes/" + args.mesh + ".xml")
        self.cell_function = MeshFunction(
            "size_t", self.mesh,
            "meshes/" + args.mesh + "_physical_region.xml")
        self.facet_function = MeshFunction(
            "size_t", self.mesh, "meshes/" + args.mesh + "_facet_region.xml")
        self.dsIn = Measure("ds",
                            subdomain_id=2,
                            subdomain_data=self.facet_function)
        self.dsOut = Measure("ds",
                             subdomain_id=3,
                             subdomain_data=self.facet_function)
        self.dsWall = Measure("ds",
                              subdomain_id=1,
                              subdomain_data=self.facet_function)
        self.dsCyl = Measure("ds",
                             subdomain_id=5,
                             subdomain_data=self.facet_function)
        self.normal = FacetNormal(self.mesh)
        print("Mesh name: ", args.mesh, "    ", self.mesh)
        print("Mesh norm max: ", self.mesh.hmax())
        print("Mesh norm min: ", self.mesh.hmin())

        self.actual_time = None
        self.v_in = None
Exemplo n.º 3
0
 def loadMesh(mesh):
     """
     :param mesh: name of mesh file (without extension)
     :return: tuple mesh, facet function read from .hdf5 file
     """
     f = HDF5File(mpi_comm_world(), 'meshes/'+mesh+'.hdf5', 'r')
     mesh = Mesh()
     f.read(mesh, 'mesh', False)
     facet_function = MeshFunction("size_t", mesh)
     f.read(facet_function, 'facet_function')
     return mesh, facet_function
Exemplo n.º 4
0
def markBoundarySubdomains(mesh, boundaries, **kwargs):
    '''Mark the boundaries of a mesh given a geometry
    
    All interior faces are marked with zero
    
    boundaries is a dictionary {label: definition of boundary}
    '''
    
    bndSubdomains = MeshFunction("size_t", mesh, mesh.geometry().dim()-1)
    bndSubdomains.set_all(0)
    
    for i in boundaries:
        class BndSubDomain(SubDomain):
            def inside(self, x, on_boundary):
                value = array([0.0])
                boundaries[i].eval(value, x)
                return (value==1.0) and on_boundary
        aux = BndSubDomain()
        aux.mark(bndSubdomains, i)
        
    # Save Dolfin XML format of the subdomains
    if 'outputXmlGz' in kwargs:
        File(kwargs['outputXmlGz']) << bndSubdomains
        
    # Save sub domains to VTK files
    if 'outputPvd' in kwargs:
        File(kwargs['outputPvd']) << bndSubdomains
        
    return bndSubdomains
    
## If there exist dirichlet boundary
#if hasDirichlet:
#    if os.path.isfile(dirichletPath):
#        dirichletSubdomain = MeshFunction("bool", mesh, dirichletPath)
#    else:
#        # Mark faces
#        dirichletSubdomain.set_all(False)
#        class Aux(SubDomain):
#            def inside(self, x, on_boundary):
#                value = array([0.0])
#                physics.dirichletBnd.eval(value, x)
#                return (value==1.0) and on_boundary
#        aux = Aux()
#        aux.mark(dirichletSubdomain, True)
#        aux.mark(bndSubdomains, 0)
Exemplo n.º 5
0
def markBoundariesOfMesh(mesh, geo, **kwargs):
    '''Mark the boundaries of a mesh given a geometry
    
    All interior faces are marked with zero
    
    If the geometry has no marks, it will be mared using the convention:
    face[0] = 1
    face[1] = 2
    ...
    face[N] = N+1
    '''
    
    # Reference point indexes in each face
    geoBndPoints = [ face[0] for face in geo._faces ]

    # Face normals
    geoNormals = geo.getNormals()

    # Create mesh functions over the cell facets
    faceSubdomains = MeshFunction("size_t", mesh, geo._nDim-1)

    # Mark all facets of the domain as 0
    faceSubdomains.set_all(0)

    # Mark boundary faces for face elements
    for i in range(geo.getNoFaces()):
        class BndSubDomain(SubDomain):
            def inside(self, x, on_boundary):
                return near( geoNormals[i].dot(Point(x)-geo._points[geoBndPoints[i]]), 0.0 ) and on_boundary
        aSubDomain = BndSubDomain()
        label = i+1
        if hasattr(geo, 'facesMarkers'):
            label = geo.facesMarkers[i]
        aSubDomain.mark(faceSubdomains, label)
        
    # Save Dolfin XML format of the subdomains
    if 'outputXmlGz' in kwargs:
        File(kwargs['outputXmlGz']) << faceSubdomains
        
    # Save sub domains to VTK files
    if 'outputPvd' in kwargs:
        File(kwargs['outputPvd']) << faceSubdomains
        
    return faceSubdomains
# Load mesh
if isfile(meshPath):
    mesh = Mesh(meshPath)
else:
    print("Mesh bndFile does not exist!")
    exit(1)
#plot(mesh, interactive=True)

###
### Mesh
###

# Here we consider 0 as a internal face
bndSubdomains = markBoundariesOfMesh(mesh, geo, outputPvd="localBoundary.pvd")
globalBndSubdomains = MeshFunction("size_t", mesh, geo._nDim - 1)

# If there exist marked boundary
if 'boundaries' in dir(physics):
    if (reutilizeBoundaryInfo and isfile(bndPath)):
        globalBndSubdomains = MeshFunction("size_t", mesh, bndPath)
    else:
        globalBndSubdomains = markBoundarySubdomains(mesh,
                                                     physics.boundaries,
                                                     outputXmlGz=bndPath,
                                                     outputPvd=bndPvd)
else:
    globalBndSubdomains.set_all(0)

# Boundary measures
ds = Measure('ds', domain=mesh, subdomain_data=bndSubdomains)
Exemplo n.º 7
0
def construct_from_mesh_functions(dim, A_expr, mesh):
    """
    :param dim: geometrical dimension
    :param A_expr: expression defining diffusion matrix
    :param mesh: mesh-discretization of the domain
    :return: cell-wise function
    """

    # Define scalar cell-wise function for dim = 1
    a00 = MeshFunction("double", mesh, dim)
    # Define function expression from the problem data (depending on how many of the conditions are discussed )
    A1 = A_expr[0]
    A2 = A_expr[1]

    # Case for dimension higher then one (symmetric case)
    if dim >= 2:
        a01 = MeshFunction("double", mesh, dim)
        a11 = MeshFunction("double", mesh, dim)
    # Case for dimension higher then two (symmetric case)
    if dim >= 3:
        a02 = MeshFunction("double", mesh, dim)
        a12 = MeshFunction("double", mesh, dim)
        a22 = MeshFunction("double", mesh, dim)

    for cell in cells(mesh):
        if cell.midpoint().x(
        ) < 0.5:  # this condition checks whethe the elements on the left part of the domain
            A = A_expr[0]
        else:
            A = A_expr[1]

        a00[cell] = A[0][0]
        if dim >= 2:
            a11[cell] = A[1][1]
            a01[cell] = A[0][1]
        if dim >= 3:
            a02[cell] = A[0][2]
            a12[cell] = A[1][2]
            a22[cell] = A[2][2]

    # Code for C++ evaluation of conductivity
    conductivity_code = """

    class Conductivity : public Expression
    {
    public:

      // Create expression with 3 components
      Conductivity() : Expression(3) {}

      // Function for evaluating expression on each cell
      void eval(Array<double>& values, const Array<double>& x, const ufc::cell& cell) const
      {
        const uint D = cell.topological_dimension;
        const uint cell_index = cell.index;
        values[0] = (*a00)[cell_index];
        values[1] = (*a01)[cell_index];
        values[2] = (*a11)[cell_index];
      }

      // The data stored in mesh functions
      std::shared_ptr<MeshFunction<double> > a00;
      std::shared_ptr<MeshFunction<double> > a01;
      std::shared_ptr<MeshFunction<double> > a11;

    };
    """
    # Define expression via C++ code
    a = Expression(cppcode=conductivity_code)
    a.a00 = a00
    if dim >= 2:
        a.a01 = a01
        a.a11 = a11
    if dim >= 3:
        a.a02 = a02
        a.a12 = a12
        a.a22 = a22
    # Define matrix depending on the dimension
    if dim == 1:
        A = a[0]
    elif dim == 2:
        # A = |a[0] a[1]|
        #     |a[1] a[2]|
        A = as_matrix(((a[0], a[1]), (a[1], a[2])))
    elif dim == 3:
        # A = |a[0] a[1] a[2]|
        #     |a[1] a[3] a[4]|
        #     |a[2] a[4] a[5]|
        A = as_matrix(
            ((a[0], a[1], a[2]), (a[1], a[3], a[4]), (a[2], a[3], a[5])))

    return A