Exemple #1
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    def create(self, pc):
        self.diag = None
        kspNS = PETSc.KSP()
        kspNS.create(comm=PETSc.COMM_WORLD)
        pcNS = kspNS.getPC()
        kspNS.setType('gmres')
        pcNS.setType('python')
        pcNS.setPythonContext(
            NSprecond.PCDdirect(
                MixedFunctionSpace([self.Fspace[0], self.Fspace[1]]), self.Q,
                self.F, self.L))
        kspNS.setTolerances(1e-3)
        kspNS.setFromOptions()
        self.kspNS = kspNS

        kspM = PETSc.KSP()
        kspM.create(comm=PETSc.COMM_WORLD)
        pcM = kspM.getPC()

        kspM.setType('gmres')
        pcM.setType('python')
        kspM.setTolerances(1e-3)
        pcM.setPythonContext(
            MP.Direct(MixedFunctionSpace([self.Fspace[2], self.Fspace[3]])))
        kspM.setFromOptions()
        self.kspM = kspM
Exemple #2
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def ball_in_tube():
    mesh = Mesh("../meshes/2d/ball-in-tube-cylindrical-coarse4.xml")
    V0 = FunctionSpace(mesh, "CG", 2)
    V1 = FunctionSpace(mesh, "B", 3)
    V = V0 + V1
    W = MixedFunctionSpace([V, V])

    P = FunctionSpace(mesh, "CG", 1)

    # Define mesh and boundaries.
    class LeftBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[0] < GMSH_EPS

    left_boundary = LeftBoundary()

    class RightBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[0] > 1.0 - GMSH_EPS

    right_boundary = RightBoundary()

    class LowerBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[1] < GMSH_EPS

    lower_boundary = LowerBoundary()

    class UpperBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[1] > 5.0 - GMSH_EPS

    class CoilBoundary(SubDomain):
        def inside(self, x, on_boundary):
            # One has to pay a little bit of attention when defining the
            # coil boundary; it's easy to miss the edges closest to x[0]=0.
            return (
                on_boundary
                and x[1] > 1.0 - GMSH_EPS
                and x[1] < 2.0 + GMSH_EPS
                and x[0] < 1.0 - GMSH_EPS
            )

    coil_boundary = CoilBoundary()

    u_bcs = [
        DirichletBC(W, (0.0, 0.0), right_boundary),
        DirichletBC(W.sub(0), 0.0, left_boundary),
        DirichletBC(W, (0.0, 0.0), lower_boundary),
        DirichletBC(W, (0.0, 0.0), coil_boundary),
    ]
    p_bcs = []
    # p_bcs = [DirichletBC(Q, 0.0, upper_boundary)]
    return mesh, W, P, u_bcs, p_bcs
Exemple #3
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def rotating_lid():
    mesh = UnitSquareMesh(20, 20, "left/right")

    # Define mesh and boundaries.
    class LeftBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[0] < GMSH_EPS

    class RightBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[0] > 1.0 - GMSH_EPS

    class LowerBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[1] < GMSH_EPS

    class UpperBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[1] > 1.0 - DOLFIN_EPS

    class RestrictedUpperBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return (
                on_boundary
                and x[1] > 1.0 - DOLFIN_EPS
                and DOLFIN_EPS < x[0]
                and x[0] < 0.5 - DOLFIN_EPS
            )

    left = LeftBoundary()
    right = RightBoundary()
    lower = LowerBoundary()
    upper = UpperBoundary()
    restricted_upper = RestrictedUpperBoundary()

    V = FunctionSpace(mesh, "CG", 2)

    W = MixedFunctionSpace([V, V, V])
    u_bcs = [
        DirichletBC(W.sub(0), 0.0, left),
        DirichletBC(W.sub(2), 0.0, left),
        DirichletBC(W, Constant((0.0, 0.0, 0.0)), right),
        DirichletBC(W.sub(0), 0.0, upper),
        DirichletBC(W.sub(1), 0.0, upper),
        DirichletBC(W.sub(2), Expression("x[0]", degree=1), restricted_upper),
        DirichletBC(W, Constant((0.0, 0.0, 0.0)), lower),
    ]

    P = FunctionSpace(mesh, "CG", 1)
    p_bcs = []
    return mesh, W, P, u_bcs, p_bcs
Exemple #4
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def increase_order(V):
    """
    For a given function space, return the same space, but with a
    higher polynomial degree
    """

    n = V.num_sub_spaces()
    if n > 0:
        spaces = []
        for i in range(n):
            V_i = V.sub(i)
            element = V_i.ufl_element()
            # Handle VectorFunctionSpaces specially
            if isinstance(element, ufl.VectorElement):
                spaces += [
                    VectorFunctionSpace(V_i.mesh(),
                                        element.family(),
                                        element.degree() + 1,
                                        dim=element.num_sub_elements())
                ]
            # Handle all else as MixedFunctionSpaces
            else:
                spaces += [increase_order(V_i)]

        return MixedFunctionSpace(spaces)

    if V.ufl_element().family() == "Real":
        return FunctionSpace(V.mesh(), "Real", 0)

    return FunctionSpace(V.mesh(),
                         V.ufl_element().family(),
                         V.ufl_element().degree() + 1)
Exemple #5
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def derivative(form, u, du=None, coefficient_derivatives=None):
    if du is None:
        # Get existing arguments from form and position the new one with the next argument number
        from ufl.algorithms import extract_arguments
        form_arguments = extract_arguments(form)

        number = max([-1] + [arg.number() for arg in form_arguments]) + 1

        if any(arg.part() is not None for arg in form_arguments):
            cpp.dolfin_error(
                "formmanipulation.py", "compute derivative of form",
                "Cannot automatically create third argument using parts, please supply one"
            )
        part = None

        if isinstance(u, Function):
            V = u.function_space()
            du = Argument(V, number, part)
        elif isinstance(u, (list, tuple)) and all(
                isinstance(w, Function) for w in u):
            V = MixedFunctionSpace([w.function_space() for w in u])
            du = ufl.split(Argument(V, number, part))
        else:
            cpp.dolfin_error(
                "formmanipulation.py", "compute derivative of form",
                "Cannot automatically create third argument, please supply one"
            )
    return ufl.derivative(form, u, du, coefficient_derivatives)
def change_regularity(V, family):
    """
    For a given function space, return the corresponding space with
    the finite elements specified by 'family'. Possible families
    are the families supported by the form compiler
    """

    n = V.num_sub_spaces()
    if n > 0:
        return MixedFunctionSpace([change_regularity(V.sub(i), family)
                                   for i in range(n)])

    element = V.ufl_element()
    shape = element.value_shape()
    if not shape:
        return FunctionSpace(V.mesh(), family, element.degree())

    return MixedFunctionSpace([FunctionSpace(V.mesh(), family, element.degree())
                               for i in range(shape[0])])
def derivative(form, u, du=None):
    if du is None:
        if isinstance(u, Function):
            V = u.function_space()
            du = Argument(V)
        elif isinstance(u, (list, tuple)) and all(
                isinstance(w, Function) for w in u):
            V = MixedFunctionSpace([w.function_space() for w in u])
            du = ufl.split(Argument(V))
        else:
            cpp.dolfin_error(
                "formmanipulation.py", "compute derivative of form",
                "Cannot automatically create third argument, please supply one"
            )

    return ufl.derivative(form, u, du)
Exemple #8
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def make_function_spaces(mesh, element):
    'Create mixed function space on the mesh.'
    assert hasattr(element, 'V') and hasattr(element, 'Q')

    # Create velocity space
    n = len(element.V)
    assert n > 0
    V = VectorFunctionSpace(mesh, *element.V[0])
    for i in range(1, n):
        V += VectorFunctionSpace(mesh, *element.V[i])

    # Create pressure space
    assert len(element.Q) == 1
    Q = FunctionSpace(mesh, *element.Q[0])

    M = MixedFunctionSpace([V, Q])
    return V, Q, M
Exemple #9
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class SNDiscretization(Discretization):
  def __init__(self, problem, SN_order, verbosity=0):
    super(SNDiscretization, self).__init__(problem, verbosity)

    if self.verb > 1: print0("Obtaining angular discretization data")
    t_ordinates = Timer("Angular discretization data")

    from transport_data import ordinates_ext_module, quadrature_file
    from common import check_sn_order

    self.angular_quad = ordinates_ext_module.OrdinatesData(SN_order, self.mesh.topology().dim(), quadrature_file)
    self.M = self.angular_quad.get_M()
    self.N = check_sn_order(SN_order)

    ord_mat = [self.angular_quad.get_xi().tolist(), self.angular_quad.get_eta().tolist()]
    if self.angular_quad.get_D() == 3: ord_mat.append(self.angular_quad.get_mu().tolist())
    self.ordinates_matrix = as_matrix(ord_mat)

    if self.verb > 2:
      self.angular_quad.print_info()

  def init_solution_spaces(self, group_GS=False):
    if self.verb > 1: print0("Defining function spaces" )

    self.t_spaces.start()

    self.Vpsi1 = VectorFunctionSpace(self.mesh, "CG", self.parameters["p"], self.M)

    if not group_GS:
      self.V = MixedFunctionSpace([self.Vpsi1]*self.G)
    else:
      # Alias the solution space as Vpsi1
      self.V = self.Vpsi1

    self.Vphi1 = FunctionSpace(self.mesh, "CG", self.parameters["p"])

    self.ndof1 = self.Vpsi1.dim()
    self.ndof = self.V.dim()

    if self.verb > 1:
      print0("  {0} direction(s), {1} group(s), {2}".format(self.M, self.G, "group GS" if group_GS else "full system"))
      print0("    NDOF (solution): {0}".format(self.ndof) )
      print0("    NDOF (1gr): {0}".format(self.ndof1) )
      print0("    NDOF (1dir, 1gr): {0}".format(self.Vpsi1.sub(0).dim()) )
      print0("    NDOF (XS): {0}".format(self.ndof0) )
Exemple #10
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def createMixedFSi(Vs):
    """
    Create MixedFunctionSpace from V1 and V2
    """
    Vdim = Vs[0].dim()
    Vms = Vs[0].mesh().size(0)
    for V in Vs:
        assert Vdim == V.dim()
        assert Vms == V.mesh().size(0)

    try:
        V1V2 = MixedFunctionSpace(Vs)
    except:
        Vsfem = []
        for V in Vs:
            Vsfem.append(V.ufl_element())
        V1V2 = FunctionSpace(Vs[0].mesh(), MixedElement(Vsfem))

    return V1V2
Exemple #11
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  def init_solution_spaces(self, group_GS=False):
    if self.verb > 1: print0("Defining function spaces" )

    self.t_spaces.start()

    self.Vpsi1 = VectorFunctionSpace(self.mesh, "CG", self.parameters["p"], self.M)

    if not group_GS:
      self.V = MixedFunctionSpace([self.Vpsi1]*self.G)
    else:
      # Alias the solution space as Vpsi1
      self.V = self.Vpsi1

    self.Vphi1 = FunctionSpace(self.mesh, "CG", self.parameters["p"])

    self.ndof1 = self.Vpsi1.dim()
    self.ndof = self.V.dim()

    if self.verb > 1:
      print0("  {0} direction(s), {1} group(s), {2}".format(self.M, self.G, "group GS" if group_GS else "full system"))
      print0("    NDOF (solution): {0}".format(self.ndof) )
      print0("    NDOF (1gr): {0}".format(self.ndof1) )
      print0("    NDOF (1dir, 1gr): {0}".format(self.Vpsi1.sub(0).dim()) )
      print0("    NDOF (XS): {0}".format(self.ndof0) )
Exemple #12
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def solve(A,
          b,
          u,
          P,
          IS,
          Fspace,
          IterType,
          OuterTol,
          InnerTol,
          Mass=0,
          L=0,
          F=0):

    # u = b.duplicate()
    if IterType == "Full":

        kspOuter = PETSc.KSP().create()
        kspOuter.setTolerances(OuterTol)
        kspOuter.setType('fgmres')

        reshist = {}

        def monitor(ksp, its, fgnorm):
            reshist[its] = fgnorm
            print "OUTER:", fgnorm

        kspOuter.setMonitor(monitor)
        pcOutter = kspOuter.getPC()
        pcOutter.setType(PETSc.PC.Type.KSP)

        kspOuter.setOperators(A)

        kspOuter.max_it = 500

        kspInner = pcOutter.getKSP()
        kspInner.max_it = 100

        reshist1 = {}

        def monitor(ksp, its, fgnorm):
            reshist1[its] = fgnorm
            print "INNER:", fgnorm

        # kspInner.setMonitor(monitor)

        kspInner.setType('gmres')
        kspInner.setTolerances(InnerTol)

        pcInner = kspInner.getPC()
        pcInner.setType(PETSc.PC.Type.PYTHON)
        pcInner.setPythonContext(MHDprecond.D(Fspace, P, Mass, F, L))

        PP = PETSc.Mat().createPython([A.size[0], A.size[0]])
        PP.setType('python')
        p = PrecondMulti.P(Fspace, P, Mass, L, F)

        PP.setPythonContext(p)
        kspInner.setOperators(PP)

        tic()
        scale = b.norm()
        b = b / scale
        print b.norm()
        kspOuter.solve(b, u)
        u = u * scale
        print toc()

        # print s.getvalue()
        NSits = kspOuter.its
        del kspOuter
        Mits = kspInner.its
        del kspInner
        # print u.array
        return u, NSits, Mits

    NS_is = IS[0]
    M_is = IS[1]
    kspNS = PETSc.KSP().create()
    kspM = PETSc.KSP().create()
    kspNS.setTolerances(OuterTol)

    kspNS.setOperators(A.getSubMatrix(NS_is, NS_is),
                       P.getSubMatrix(NS_is, NS_is))
    kspM.setOperators(A.getSubMatrix(M_is, M_is), P.getSubMatrix(M_is, M_is))
    # print P.symmetric
    A.destroy()
    P.destroy()
    if IterType == "MD":
        kspNS.setType('gmres')
        kspNS.max_it = 500

        pcNS = kspNS.getPC()
        pcNS.setType(PETSc.PC.Type.PYTHON)
        pcNS.setPythonContext(
            NSprecond.PCDdirect(MixedFunctionSpace([Fspace[0], Fspace[1]]),
                                Mass, F, L))
    elif IterType == "CD":
        kspNS.setType('minres')
        pcNS = kspNS.getPC()
        pcNS.setType(PETSc.PC.Type.PYTHON)
        pcNS.setPythonContext(
            StokesPrecond.Approx(MixedFunctionSpace([Fspace[0], Fspace[1]])))
    reshist = {}

    def monitor(ksp, its, fgnorm):
        reshist[its] = fgnorm
        print fgnorm

    # kspNS.setMonitor(monitor)

    uNS = u.getSubVector(NS_is)
    bNS = b.getSubVector(NS_is)
    # print kspNS.view()
    scale = bNS.norm()
    bNS = bNS / scale
    print bNS.norm()
    kspNS.solve(bNS, uNS)
    uNS = uNS * scale
    NSits = kspNS.its
    kspNS.destroy()
    # for line in reshist.values():
    #     print line
    kspM.setFromOptions()
    kspM.setType(kspM.Type.MINRES)
    kspM.setTolerances(InnerTol)
    pcM = kspM.getPC()
    pcM.setType(PETSc.PC.Type.PYTHON)
    pcM.setPythonContext(MP.Direct(MixedFunctionSpace([Fspace[2], Fspace[3]])))

    uM = u.getSubVector(M_is)
    bM = b.getSubVector(M_is)
    scale = bM.norm()
    bM = bM / scale
    print bM.norm()
    kspM.solve(bM, uM)
    uM = uM * scale
    Mits = kspM.its
    kspM.destroy()
    u = IO.arrayToVec(np.concatenate([uNS.array, uM.array]))
    return u, NSits, Mits
Exemple #13
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    def __init__(self):
        import os
        from dolfin import Mesh, MeshFunction, SubMesh, SubDomain, \
            FacetFunction, DirichletBC, dot, grad, FunctionSpace, \
            MixedFunctionSpace, Expression, FacetNormal, pi, Function, \
            Constant, TestFunction, MPI, mpi_comm_world, File
        import numpy
        import warnings

        from maelstrom import heat_cylindrical as cyl_heat
        from maelstrom import materials_database as md

        GMSH_EPS = 1.0e-15

        current_path = os.path.dirname(os.path.realpath(__file__))
        base = os.path.join(
            current_path,
            '../../meshes/2d/crucible-with-coils'
            )
        self.mesh = Mesh(base + '.xml')
        self.subdomains = MeshFunction('size_t',
                                       self.mesh,
                                       base + '_physical_region.xml'
                                       )

        self.subdomain_materials = {
            1: md.get_material('porcelain'),
            2: md.get_material('argon'),
            3: md.get_material('GaAs (solid)'),
            4: md.get_material('GaAs (liquid)'),
            27: md.get_material('air')
            }

        # coils
        for k in range(5, 27):
            self.subdomain_materials[k] = md.get_material('graphite EK90')

        # Define the subdomains which together form a single coil.
        self.coil_domains = [
            [5, 6, 7, 8, 9],
            [10, 11, 12, 13, 14],
            [15, 16, 17, 18, 19],
            [20, 21, 22, 23],
            [24, 25, 26]
            ]

        self.wpi = 4
        # http://fenicsproject.org/qa/2026/submesh-workaround-for-parallel-computation
        submesh_parallel_bug_fixed = False
        if submesh_parallel_bug_fixed:
            submesh_workpiece = SubMesh(self.mesh, self.subdomains, self.wpi)
        else:
            # To get the mesh in parallel, we need to read it in from a file.
            # Writing out can only happen in serial mode, though. :/
            base = os.path.join(current_path,
                                '../../meshes/2d/crucible-with-coils-submesh'
                                )
            filename = base + '.xml'
            if not os.path.isfile(filename):
                warnings.warn(
                    'Submesh file \'%s\' does not exist. Creating... '
                    % filename
                    )
                if MPI.size(mpi_comm_world()) > 1:
                    raise RuntimeError(
                        'Can only write submesh in serial mode.'
                        )
                submesh_workpiece = \
                    SubMesh(self.mesh, self.subdomains, self.wpi)
                output_stream = File(filename)
                output_stream << submesh_workpiece
            # Read the mesh
            submesh_workpiece = Mesh(base + '.xml')

        coords = submesh_workpiece.coordinates()
        ymin = min(coords[:, 1])
        ymax = max(coords[:, 1])

        # Find the top right point.
        k = numpy.argmax(numpy.sum(coords, 1))
        topright = coords[k, :]

        # Initialize mesh function for boundary domains
        class Left(SubDomain):
            def inside(self, x, on_boundary):
                # Explicitly exclude the lowest and the highest point of the
                # symmetry axis.
                # It is necessary for the consistency of the pressure-Poisson
                # system in the Navier-Stokes solver that the velocity is
                # exactly 0 at the boundary r>0. Hence, at the corner points
                # (r=0, melt-crucible, melt-crystal) we must enforce u=0
                # already and cannot have a component in z-direction.
                return on_boundary \
                    and x[0] < GMSH_EPS \
                    and x[1] < ymax - GMSH_EPS \
                    and x[1] > ymin + GMSH_EPS

        class Crucible(SubDomain):
            def inside(self, x, on_boundary):
                return on_boundary \
                    and ((x[0] > GMSH_EPS and x[1] < ymax - GMSH_EPS)
                         or (x[0] > topright[0] - GMSH_EPS
                             and x[1] > topright[1] - GMSH_EPS)
                         or (x[0] < GMSH_EPS and x[1] < ymin + GMSH_EPS)
                         )

        # At the top right part (boundary melt--gas), slip is allowed, so only
        # n.u=0 is enforced. Very weirdly, the PPE is consistent if and only if
        # the end points of UpperRight are in UpperRight. This contrasts
        # Left(), where the end points must NOT belong to Left().  Judging from
        # the experiments, these settings do the right thing.
        # TODO try to better understand the PPE system/dolfin's boundary
        # settings
        class Upper(SubDomain):
            def inside(self, x, on_boundary):
                return on_boundary \
                    and x[1] > ymax - GMSH_EPS

        class UpperRight(SubDomain):
            def inside(self, x, on_boundary):
                return on_boundary \
                    and x[1] > ymax - GMSH_EPS \
                    and x[0] > 0.038 - GMSH_EPS

        # The crystal boundary is taken to reach up to 0.038 where the
        # Dirichlet boundary data is about the melting point of the crystal,
        # 1511K. This setting gives pretty acceptable results when there is no
        # convection except the one induced by buoyancy. Is there is any more
        # stirring going on, though, the end point of the crystal with its
        # fixed temperature of 1511K might be the hottest point globally. This
        # looks rather unphysical.
        # TODO check out alternatives
        class UpperLeft(SubDomain):
            def inside(self, x, on_boundary):
                return on_boundary \
                    and x[1] > ymax - GMSH_EPS \
                    and x[0] < 0.038 + GMSH_EPS

        left = Left()
        crucible = Crucible()
        upper_left = UpperLeft()
        upper_right = UpperRight()

        self.wp_boundaries = FacetFunction('size_t', submesh_workpiece)
        self.wp_boundaries.set_all(0)
        left.mark(self.wp_boundaries, 1)
        crucible.mark(self.wp_boundaries, 2)
        upper_right.mark(self.wp_boundaries, 3)
        upper_left.mark(self.wp_boundaries, 4)

        if DEBUG:
            from dolfin import plot, interactive
            plot(self.wp_boundaries, title='Boundaries')
            interactive()

        submesh_boundary_indices = {
            'left': 1,
            'crucible': 2,
            'upper right': 3,
            'upper left': 4
            }

        # Boundary conditions for the velocity.
        #
        # [1] Incompressible flow and the finite element method; volume two;
        #     Isothermal Laminar Flow;
        #     P.M. Gresho, R.L. Sani;
        #
        # For the choice of function space, [1] says:
        #     "In 2D, the triangular elements P_2^+P_1 and P_2^+P_{-1} are very
        #      good [...]. [...] If you wish to avoid bubble functions on
        #      triangular elements, P_2P_1 is not bad, and P_2(P_1+P_0) is even
        #      better [...]."
        #
        # It turns out that adding the bubble space significantly hampers the
        # convergence of the Stokes solver and also considerably increases the
        # time it takes to construct the Jacobian matrix of the Navier--Stokes
        # problem if no optimization is applied.
        V = FunctionSpace(submesh_workpiece, 'CG', 2)
        with_bubbles = False
        if with_bubbles:
            V += FunctionSpace(submesh_workpiece, 'B', 3)
        self.W = MixedFunctionSpace([V, V, V])

        self.u_bcs = [
            DirichletBC(self.W,
                        Expression(
                            ('0.0', '0.0', '-2*pi*x[0] * 5.0/60.0'),
                            degree=1
                            ),
                        #(0.0, 0.0, 0.0),
                        crucible),
            DirichletBC(self.W.sub(0), 0.0, left),
            DirichletBC(self.W.sub(2), 0.0, left),
            # Make sure that u[2] is 0 at r=0.
            DirichletBC(self.W,
                        Expression(
                            ('0.0', '0.0', '2*pi*x[0] * 5.0/60.0'),
                            degree=1
                            ),
                        upper_left),
            DirichletBC(self.W.sub(1), 0.0, upper_right),
            ]
        self.p_bcs = []

        self.P = FunctionSpace(submesh_workpiece, 'CG', 1)

        # Boundary conditions for heat equation.
        self.Q = FunctionSpace(submesh_workpiece, 'CG', 2)
        # Dirichlet.
        # This is a bit of a tough call since the boundary conditions need to
        # be read from a Tecplot file here.
        import tecplot_reader
        filename = os.path.join(
            os.path.dirname(os.path.realpath(__file__)),
            'data/crucible-boundary.dat'
            )
        data = tecplot_reader.read(filename)
        RZ = numpy.c_[data['ZONE T']['node data']['r'],
                      data['ZONE T']['node data']['z']
                      ]
        T_vals = data['ZONE T']['node data']['temp. [K]']

        class TecplotDirichletBC(Expression):
            # TODO specify degree
            def eval(self, value, x):
                # Find on which edge x sits, and raise exception if it doesn't.
                edge_found = False
                for edge in data['ZONE T']['element data']:
                    # Given a point X and an edge X0--X1,
                    #
                    #     (1 - theta) X0 + theta X1,
                    #
                    # the minimum distance is assumed for
                    #
                    #    argmin_theta ||(1-theta) X0  + theta X1 - X||^2
                    #    = <X1 - X0, X - X0> / ||X1 - X0||^2.
                    #
                    # If the distance is 0 and 0<=theta<=1, we found the edge.
                    #
                    # Note that edges are 1-based in Tecplot.
                    X0 = RZ[edge[0] - 1]
                    X1 = RZ[edge[1] - 1]
                    theta = numpy.dot(X1-X0, x-X0) / numpy.dot(X1-X0, X1-X0)
                    diff = (1.0-theta)*X0 + theta*X1 - x
                    if numpy.dot(diff, diff) < 1.0e-10 and \
                            0.0 <= theta and theta <= 1.0:
                        # Linear interpolation of the temperature value.
                        value[0] = (1.0-theta) * T_vals[edge[0]-1] \
                                 + theta       * T_vals[edge[1]-1]
                        edge_found = True
                        break
                # This class is supposed to be used for Dirichlet boundary
                # conditions. For some reason, FEniCS also evaluates
                # DirichletBC objects at coordinates which do not sit on the
                # boundary, see
                # <http://fenicsproject.org/qa/1033/dirichletbc-expressions-evaluated-away-from-the-boundary>.
                # The assigned values have no meaning though, so not assigning
                # values[0] here is okay.
                #
                #from matplotlib import pyplot as pp
                #pp.plot(x[0], x[1], 'xg')
                if not edge_found:
                    value[0] = 0.0
                    warnings.warn('Coordinate (%e, %e) doesn\'t sit on edge.'
                                  % (x[0], x[1]))
                    #pp.plot(RZ[:, 0], RZ[:, 1], '.k')
                    #pp.plot(x[0], x[1], 'xr')
                    #pp.show()
                    #raise RuntimeError('Input coordinate '
                    #                   '%r is not on boundary.' % x)
                return

        tecplot_dbc = TecplotDirichletBC()
        self.theta_bcs_d = [
            DirichletBC(self.Q, tecplot_dbc, upper_left)
            ]
        theta_bcs_d_strict = [
            DirichletBC(self.Q, tecplot_dbc, upper_right),
            DirichletBC(self.Q, tecplot_dbc, crucible),
            DirichletBC(self.Q, tecplot_dbc, upper_left)
            ]

        # Neumann
        dTdr_vals = data['ZONE T']['node data']['dTempdx [K/m]']
        dTdz_vals = data['ZONE T']['node data']['dTempdz [K/m]']

        class TecplotNeumannBC(Expression):
            # TODO specify degree
            def eval(self, value, x):
                # Same problem as above: This expression is not only evaluated
                # at boundaries.
                for edge in data['ZONE T']['element data']:
                    X0 = RZ[edge[0] - 1]
                    X1 = RZ[edge[1] - 1]
                    theta = numpy.dot(X1-X0, x-X0) / numpy.dot(X1-X0, X1-X0)
                    dist = numpy.linalg.norm((1-theta)*X0 + theta*X1 - x)
                    if dist < 1.0e-5 and 0.0 <= theta and theta <= 1.0:
                        value[0] = (1-theta) * dTdr_vals[edge[0]-1] \
                            + theta * dTdr_vals[edge[1]-1]
                        value[1] = (1-theta) * dTdz_vals[edge[0]-1] \
                            + theta * dTdz_vals[edge[1]-1]
                        break
                return

            def value_shape(self):
                return (2,)

        tecplot_nbc = TecplotNeumannBC()
        n = FacetNormal(self.Q.mesh())
        self.theta_bcs_n = {
            submesh_boundary_indices['upper right']: dot(n, tecplot_nbc),
            submesh_boundary_indices['crucible']: dot(n, tecplot_nbc)
            }
        self.theta_bcs_r = {}

        # It seems that the boundary conditions from above are inconsistent in
        # that solving with Dirichlet overall and mixed Dirichlet-Neumann give
        # different results; the value *cannot* correspond to one solution.
        # From looking at the solutions, the pure Dirichlet setting appears
        # correct, so extract the Neumann values directly from that solution.
        zeta = TestFunction(self.Q)

        theta_reference = Function(self.Q, name='temperature (Dirichlet)')
        theta_reference.vector()[:] = 0.0

        # Solve the *quasilinear* PDE (coefficients may depend on theta).
        # This is to avoid setting a fixed temperature for the coefficients.

        # Get material parameters
        wp_material = self.subdomain_materials[self.wpi]
        if isinstance(wp_material.specific_heat_capacity, float):
            cp = wp_material.specific_heat_capacity
        else:
            cp = wp_material.specific_heat_capacity(theta_reference)
        if isinstance(wp_material.density, float):
            rho = wp_material.density
        else:
            rho = wp_material.density(theta_reference)
        if isinstance(wp_material.thermal_conductivity, float):
            k = wp_material.thermal_conductivity
        else:
            k = wp_material.thermal_conductivity(theta_reference)

        reference_problem = cyl_heat.HeatCylindrical(
            self.Q, theta_reference,
            zeta,
            b=Constant((0.0, 0.0, 0.0)),
            kappa=k,
            rho=rho,
            cp=cp,
            source=Constant(0.0),
            dirichlet_bcs=theta_bcs_d_strict
            )

        from dolfin import solve
        solve(reference_problem.F0 == 0,
              theta_reference,
              bcs=theta_bcs_d_strict
              )

        # Create equivalent boundary conditions from theta_reference. This
        # makes sure that the potentially expensive Expression evaluation in
        # theta_bcs_* is replaced by something reasonably cheap.
        for k, bc in enumerate(self.theta_bcs_d):
            self.theta_bcs_d[k] = DirichletBC(bc.function_space(),
                                              theta_reference,
                                              bc.domain_args[0]
                                              )
        # Adapt Neumann conditions.
        n = FacetNormal(self.Q.mesh())
        for k in self.theta_bcs_n:
            self.theta_bcs_n[k] = dot(n, grad(theta_reference))

        if DEBUG:
            # Solve the heat equation with the mixed Dirichlet-Neumann
            # boundary conditions and compare it to the Dirichlet-only
            # solution.
            theta_new = Function(
                self.Q,
                name='temperature (Neumann + Dirichlet)'
                )
            from dolfin import Measure
            ds_workpiece = Measure('ds')[self.wp_boundaries]
            problem_new = cyl_heat.HeatCylindrical(
                self.Q, theta_new,
                zeta,
                b=Constant((0.0, 0.0, 0.0)),
                kappa=k,
                rho=rho,
                cp=cp,
                source=Constant(0.0),
                dirichlet_bcs=self.theta_bcs_d,
                neumann_bcs=self.theta_bcs_n,
                ds=ds_workpiece
                )

            from dolfin import solve
            solve(problem_new.F0 == 0,
                  theta_new,
                  bcs=problem_new.dirichlet_bcs
                  )
            from dolfin import plot, interactive, errornorm
            print('||theta_new - theta_ref|| = %e'
                  % errornorm(theta_new, theta_reference)
                  )
            plot(theta_reference)
            plot(theta_new)
            plot(
                theta_reference - theta_new,
                title='theta_ref - theta_new'
                )
            interactive()

        #omega = 2 * pi * 10.0e3
        self.omega = 2 * pi * 300.0

        return
Exemple #14
0
    def solve(self, problem):
        self.problem = problem
        doSave = problem.doSave
        save_this_step = False
        onlyVel = problem.saveOnlyVel
        dt = self.metadata['dt']

        nu = Constant(self.problem.nu)
        self.tc.init_watch('init', 'Initialization', True, count_to_percent=False)
        self.tc.init_watch('solve', 'Running nonlinear solver', True, count_to_percent=True)
        self.tc.init_watch('next', 'Next step assignments', True, count_to_percent=True)
        self.tc.init_watch('saveVel', 'Saved velocity', True)

        self.tc.start('init')

        mesh = self.problem.mesh

        # Define function spaces (P2-P1)
        self.V = VectorFunctionSpace(mesh, "Lagrange", 2)  # velocity
        self.Q = FunctionSpace(mesh, "Lagrange", 1)  # pressure
        self.W = MixedFunctionSpace([self.V, self.Q])
        self.PS = FunctionSpace(mesh, "Lagrange", 2)  # partial solution (must be same order as V)
        self.D = FunctionSpace(mesh, "Lagrange", 1)   # velocity divergence space

        # to assign solution in space W.sub(0) to Function(V) we need FunctionAssigner (cannot be assigned directly)
        fa = FunctionAssigner(self.V, self.W.sub(0))
        velSp = Function(self.V)

        problem.initialize(self.V, self.Q, self.PS, self.D)

        # Define unknown and test function(s) NS
        v, q = TestFunctions(self.W)
        w = Function(self.W)
        dw = TrialFunction(self.W)
        u, p = split(w)

        # Define fields
        n = FacetNormal(mesh)
        I = Identity(u.geometric_dimension())
        theta = 0.5  # Crank-Nicholson
        k = Constant(self.metadata['dt'])

        # Initial conditions: u0 velocity at previous time step u1 velocity two time steps back p0 previous pressure
        [u0, p0] = self.problem.get_initial_conditions([{'type': 'v', 'time': 0.0}, {'type': 'p', 'time': 0.0}])

        if doSave:
            problem.save_vel(False, u0, 0.0)

        # boundary conditions
        bcu, bcp = problem.get_boundary_conditions(self.bc == 'outflow', self.W.sub(0), self.W.sub(1))
        # NT bcp is not used

        # Define steady part of the equation
        def T(u):
            return -p * I + 2.0 * nu * sym(grad(u))

        def F(u, v, q):
            return (inner(T(u), grad(v)) - q * div(u)) * dx + inner(grad(u) * u, v) * dx

        # Define variational forms
        F_ns = (inner((u - u0), v) / k) * dx + (1.0 - theta) * F(u0, v, q) + theta * F(u, v, q)
        J_ns = derivative(F_ns, w, dw)
        # J_ns = derivative(F_ns, w)  # did not work

        # NS_problem = NonlinearVariationalProblem(F_ns, w, bcu, J_ns, form_compiler_parameters=ffc_options)
        NS_problem = NonlinearVariationalProblem(F_ns, w, bcu, J_ns)
        # (var. formulation, unknown, Dir. BC, jacobian, optional)
        NS_solver = NonlinearVariationalSolver(NS_problem)

        prm = NS_solver.parameters
        prm['newton_solver']['absolute_tolerance'] = 1E-08
        prm['newton_solver']['relative_tolerance'] = 1E-08
        # prm['newton_solver']['maximum_iterations'] = 45
        # prm['newton_solver']['relaxation_parameter'] = 1.0
        prm['newton_solver']['linear_solver'] = 'mumps'

        info(NS_solver.parameters, True)

        self.tc.end('init')

        # Time-stepping
        info("Running of direct method")
        ttime = self.metadata['time']
        t = dt
        step = 1
        while t < (ttime + dt/2.0):
            info("t = %f" % t)
            self.problem.update_time(t, step)
            if self.MPI_rank == 0:
                problem.write_status_file(t)

            if doSave:
                save_this_step = problem.save_this_step

            # Compute
            begin("Solving NS ....")
            try:
                self.tc.start('solve')
                NS_solver.solve()
                self.tc.end('solve')
            except RuntimeError as inst:
                problem.report_fail(t)
                return 1
            end()

            # Extract solutions:
            (u, p) = w.split()
            fa.assign(velSp, u)
            # we are assigning twice (now and inside save_vel), but it works with one method save_vel for direct and
            #   projection (we could split save_vel to save one assign)

            if save_this_step:
                self.tc.start('saveVel')
                problem.save_vel(False, velSp, t)
                self.tc.end('saveVel')
            if save_this_step and not onlyVel:
                problem.save_div(False, u)
            problem.compute_err(False, u, t)
            problem.compute_div(False, u)

            # foo = Function(self.Q)
            # foo.assign(p)
            # problem.averaging_pressure(foo)
            # if save_this_step and not onlyVel:
            #     problem.save_pressure(False, foo)

            if save_this_step and not onlyVel:
                problem.save_pressure(False, p)

            # compute functionals (e. g. forces)
            problem.compute_functionals(u, p, t)

            # Move to next time step
            self.tc.start('next')
            u0.assign(velSp)
            t = round(t + dt, 6)  # round time step to 0.000001
            step += 1
            self.tc.end('next')

        info("Finished: direct method")
        problem.report()
        return 0
Exemple #15
0
class Solver(gs.GeneralSolver):
    def __init__(self, args, tc, metadata):
        gs.GeneralSolver.__init__(self, args, tc, metadata)
        self.metadata['hasTentativeV'] = False

        self.solver_vel_tent = None
        self.solver_vel_cor = None
        self.solver_p = None
        self.solver_rot = None
        self.null_space = None

        # input parameters
        self.bc = args.bc
        self.forceOutflow = args.fo
        self.useLaplace = args.laplace
        self.use_full_SUPG = args.cs
        self.bcv = 'NOT' if self.useLaplace else args.bcv
        if self.bcv == 'CDN':
            info('Using classical do nothing condition (Tn=0).')
        if self.bcv == 'DDN':
            info('Using directional do nothing condition (Tn=0.5*negative(u.n)u).')
        if self.bcv == 'LAP':
            info('Using laplace neutral condition (grad(u)n=0).')
        self.stabCoef = args.stab
        self.stabilize = (args.stab > DOLFIN_EPS)
        if self.stabilize:
            if self.use_full_SUPG:
                info('Used consistent streamline-diffusion stabilization with coef.: %f' % args.stab)
            else:
                info('Used non-consistent streamline-diffusion stabilization with coef.: %f' % args.stab)
        else:
            info('No stabilization used.')
        self.solvers = args.solvers
        self.useRotationScheme = args.r
        self.metadata['hasTentativeP'] = self.useRotationScheme

        self.B = args.B
        self.use_ema = args.ema
        self.cbcDelta = args.cbcDelta
        self.prec_v = args.precV
        self.prec_p = args.precP
        self.precision_rel_v_tent = args.prv1
        self.precision_abs_v_tent = args.pav1
        self.precision_p = args.pp

    def __str__(self):
        return 'ipcs1 - incremental pressure correction scheme with nonlinearity treated by Adam-Bashword + ' \
               'Crank-Nicolson and viscosity term treated semi-explicitly (Crank-Nicholson)'

    @staticmethod
    def setup_parser_options(parser):
        gs.GeneralSolver.setup_parser_options(parser)
        parser.add_argument('-s', '--solvers', help='Solvers', choices=['direct', 'krylov'], default='krylov')
        parser.add_argument('--prv1', help='relative tentative velocity Krylov solver precision', type=int, default=6)
        parser.add_argument('--pav1', help='absolute tentative velocity Krylov solver precision', type=int, default=10)
        parser.add_argument('--pp', help='pressure Krylov solver precision', type=int, default=10)
        parser.add_argument('-b', '--bc', help='Pressure boundary condition mode',
                            choices=['outflow', 'nullspace', 'nullspace_s', 'lagrange'], default='outflow')
        parser.add_argument('--precV', help='Preconditioner for tentative velocity solver', type=str, default='ilu')
        parser.add_argument('--precP', help='Preconditioner for pressure solver', choices=['hypre_amg', 'ilu'],
                            default='hypre_amg')
        parser.add_argument('-r', help='Use rotation scheme', action='store_true')
        parser.add_argument('-B', help='Use no BC in correction step', action='store_true')
        parser.add_argument('--fo', help='Force Neumann outflow boundary for pressure', action='store_true')
        parser.add_argument('--laplace', help='Use laplace(u) instead of div(symgrad(u))', action='store_true')
        parser.add_argument('--stab', help='Use stabilization (positive constant)', type=float, default=0.)
        parser.add_argument('--bcv', help='Oufflow BC for velocity (with stress formulation)',
                            choices=['CDN', 'DDN', 'LAP'], default='CDN')
        parser.add_argument('--ema', help='Use EMA conserving scheme for convection term', action='store_true')
        # described in Charnyi, Heister, Olshanskii, Rebholz:
        # "On conservation laws of Navier-Stokes Galerkin discretizations" (2016)
        parser.add_argument('--cs', help='Use consistent SUPG stabilisation.', action='store_true')
        parser.add_argument('--cbcDelta', help='Use simpler cbcflow parameter for SUPG', action='store_true')

    def solve(self, problem):
        self.problem = problem
        doSave = problem.doSave
        save_this_step = False
        onlyVel = problem.saveOnlyVel
        dt = self.metadata['dt']

        nu = Constant(self.problem.nu)
        self.tc.init_watch('init', 'Initialization', True, count_to_percent=False)
        self.tc.init_watch('solve', 'Running nonlinear solver', True, count_to_percent=True)
        self.tc.init_watch('next', 'Next step assignments', True, count_to_percent=True)
        self.tc.init_watch('saveVel', 'Saved velocity', True)

        self.tc.start('init')

        mesh = self.problem.mesh

        # Define function spaces (P2-P1)
        self.V = VectorFunctionSpace(mesh, "Lagrange", 2)  # velocity
        self.Q = FunctionSpace(mesh, "Lagrange", 1)  # pressure
        self.W = MixedFunctionSpace([self.V, self.Q])
        self.PS = FunctionSpace(mesh, "Lagrange", 2)  # partial solution (must be same order as V)
        self.D = FunctionSpace(mesh, "Lagrange", 1)   # velocity divergence space

        # to assign solution in space W.sub(0) to Function(V) we need FunctionAssigner (cannot be assigned directly)
        fa = FunctionAssigner(self.V, self.W.sub(0))
        velSp = Function(self.V)

        problem.initialize(self.V, self.Q, self.PS, self.D)

        # Define unknown and test function(s) NS
        v, q = TestFunctions(self.W)
        w = Function(self.W)
        dw = TrialFunction(self.W)
        u, p = split(w)

        # Define fields
        n = FacetNormal(mesh)
        I = Identity(u.geometric_dimension())
        theta = 0.5  # Crank-Nicholson
        k = Constant(self.metadata['dt'])

        # Initial conditions: u0 velocity at previous time step u1 velocity two time steps back p0 previous pressure
        [u0, p0] = self.problem.get_initial_conditions([{'type': 'v', 'time': 0.0}, {'type': 'p', 'time': 0.0}])

        if doSave:
            problem.save_vel(False, u0, 0.0)

        # boundary conditions
        bcu, bcp = problem.get_boundary_conditions(self.bc == 'outflow', self.W.sub(0), self.W.sub(1))
        # NT bcp is not used

        # Define steady part of the equation
        def T(u):
            return -p * I + 2.0 * nu * sym(grad(u))

        def F(u, v, q):
            return (inner(T(u), grad(v)) - q * div(u)) * dx + inner(grad(u) * u, v) * dx

        # Define variational forms
        F_ns = (inner((u - u0), v) / k) * dx + (1.0 - theta) * F(u0, v, q) + theta * F(u, v, q)
        J_ns = derivative(F_ns, w, dw)
        # J_ns = derivative(F_ns, w)  # did not work

        # NS_problem = NonlinearVariationalProblem(F_ns, w, bcu, J_ns, form_compiler_parameters=ffc_options)
        NS_problem = NonlinearVariationalProblem(F_ns, w, bcu, J_ns)
        # (var. formulation, unknown, Dir. BC, jacobian, optional)
        NS_solver = NonlinearVariationalSolver(NS_problem)

        prm = NS_solver.parameters
        prm['newton_solver']['absolute_tolerance'] = 1E-08
        prm['newton_solver']['relative_tolerance'] = 1E-08
        # prm['newton_solver']['maximum_iterations'] = 45
        # prm['newton_solver']['relaxation_parameter'] = 1.0
        prm['newton_solver']['linear_solver'] = 'mumps'

        info(NS_solver.parameters, True)

        self.tc.end('init')

        # Time-stepping
        info("Running of direct method")
        ttime = self.metadata['time']
        t = dt
        step = 1
        while t < (ttime + dt/2.0):
            info("t = %f" % t)
            self.problem.update_time(t, step)
            if self.MPI_rank == 0:
                problem.write_status_file(t)

            if doSave:
                save_this_step = problem.save_this_step

            # Compute
            begin("Solving NS ....")
            try:
                self.tc.start('solve')
                NS_solver.solve()
                self.tc.end('solve')
            except RuntimeError as inst:
                problem.report_fail(t)
                return 1
            end()

            # Extract solutions:
            (u, p) = w.split()
            fa.assign(velSp, u)
            # we are assigning twice (now and inside save_vel), but it works with one method save_vel for direct and
            #   projection (we could split save_vel to save one assign)

            if save_this_step:
                self.tc.start('saveVel')
                problem.save_vel(False, velSp, t)
                self.tc.end('saveVel')
            if save_this_step and not onlyVel:
                problem.save_div(False, u)
            problem.compute_err(False, u, t)
            problem.compute_div(False, u)

            # foo = Function(self.Q)
            # foo.assign(p)
            # problem.averaging_pressure(foo)
            # if save_this_step and not onlyVel:
            #     problem.save_pressure(False, foo)

            if save_this_step and not onlyVel:
                problem.save_pressure(False, p)

            # compute functionals (e. g. forces)
            problem.compute_functionals(u, p, t)

            # Move to next time step
            self.tc.start('next')
            u0.assign(velSp)
            t = round(t + dt, 6)  # round time step to 0.000001
            step += 1
            self.tc.end('next')

        info("Finished: direct method")
        problem.report()
        return 0
Exemple #16
0
def solve(A,b,u,IS,Fspace,IterType,OuterTol,InnerTol,HiptmairMatrices,KSPlinearfluids,kspF,Fp,MatrixLinearFluids,kspFp):

    if IterType == "Full":
        kspOuter = PETSc.KSP().create()
        kspOuter.setTolerances(OuterTol)
        kspOuter.setType('fgmres')

        u_is = PETSc.IS().createGeneral(range(Fspace[0].dim()))
        p_is = PETSc.IS().createGeneral(range(Fspace[0].dim(),Fspace[0].dim()+Fspace[1].dim()))
        Bt = A.getSubMatrix(u_is,p_is)

        reshist = {}
        def monitor(ksp, its, fgnorm):
            reshist[its] = fgnorm
            print "OUTER:", fgnorm
        kspOuter.setMonitor(monitor)
        pcOutter = kspOuter.getPC()
        pcOutter.setType(PETSc.PC.Type.KSP)

        kspOuter.setOperators(A,A)
        kspOuter.max_it = 500

        kspInner = pcOutter.getKSP()
        kspInner.max_it = 100

        kspInner.max_it = 100
        reshist1 = {}
        def monitor(ksp, its, fgnorm):
            reshist1[its] = fgnorm
            print "INNER:", fgnorm
        # kspInner.setMonitor(monitor)

        kspInner.setType('gmres')
        kspInner.setTolerances(InnerTol)

        pcInner = kspInner.getPC()
        pcInner.setType(PETSc.PC.Type.PYTHON)
        pcInner.setPythonContext(MHDstabPrecond.InnerOuterWITHOUT(Fspace,kspF, KSPlinearfluids[0], KSPlinearfluids[1],Fp, HiptmairMatrices[3], HiptmairMatrices[4], HiptmairMatrices[2], HiptmairMatrices[0], HiptmairMatrices[1], HiptmairMatrices[6],1e-6,A))

        PP = PETSc.Mat().createPython([A.size[0], A.size[0]])
        PP.setType('python')
        p = PrecondMulti.MultiApply(Fspace,A,HiptmairMatrices[6],MatrixLinearFluids[1],MatrixLinearFluids[0],kspFp, HiptmairMatrices[3])

        PP.setPythonContext(p)
        kspInner.setOperators(PP)

        tic()
        scale = b.norm()
        b = b/scale
        print b.norm()
        kspOuter.solve(b, u)
        u = u*scale
        print toc()

        # print s.getvalue()
        NSits = kspOuter.its
        del kspOuter
        Mits = kspInner.its
        del kspInner
        # print u.array
        return u,NSits,Mits

    NS_is = IS[0]
    M_is = IS[1]
    kspNS = PETSc.KSP().create()
    kspM = PETSc.KSP().create()
    kspNS.setTolerances(OuterTol)

    kspNS.setOperators(A.getSubMatrix(NS_is,NS_is))
    kspM.setOperators(A.getSubMatrix(M_is,M_is))
    del A

    uNS = u.getSubVector(NS_is)
    bNS = b.getSubVector(NS_is)
    kspNS.setType('gmres')
    pcNS = kspNS.getPC()
    kspNS.setTolerances(OuterTol)
    pcNS.setType(PETSc.PC.Type.PYTHON)
    if IterType == "MD":
        pcNS.setPythonContext(NSpreconditioner.NSPCD(MixedFunctionSpace([Fspace[0],Fspace[1]]), kspF, KSPlinearfluids[0], KSPlinearfluids[1],Fp))
    else:
        pcNS.setPythonContext(StokesPrecond.MHDApprox(MixedFunctionSpace([Fspace[0],Fspace[1]]), kspF, KSPlinearfluids[1]))

    scale = bNS.norm()
    bNS = bNS/scale
    start_time = time.time()
    kspNS.solve(bNS, uNS)
    print ("{:25}").format("NS, time: "), " ==>  ",("{:4f}").format(time.time() - start_time),("{:9}").format("   Its: "), ("{:4}").format(kspNS.its),  ("{:9}").format("   time: "), ("{:4}").format(time.strftime('%X %x %Z')[0:5])
    uNS = scale*uNS

    NSits = kspNS.its
    # kspNS.destroy()
    # for line in reshist.values():
    #     print line

    kspM.setFromOptions()
    kspM.setType(kspM.Type.MINRES)
    kspM.setTolerances(InnerTol)
    pcM = kspM.getPC()
    pcM.setType(PETSc.PC.Type.PYTHON)
    pcM.setPythonContext(MP.Hiptmair(MixedFunctionSpace([Fspace[2],Fspace[3]]), HiptmairMatrices[3], HiptmairMatrices[4], HiptmairMatrices[2], HiptmairMatrices[0], HiptmairMatrices[1], HiptmairMatrices[6],1e-6))


    # x = x*scale
    uM = u.getSubVector(M_is)
    bM = b.getSubVector(M_is)

    scale = bM.norm()
    bM = bM/scale
    start_time = time.time()
    kspM.solve(bM, uM)
    print ("{:25}").format("Maxwell solve, time: "), " ==>  ",("{:4f}").format(time.time() - start_time),("{:9}").format("   Its: "), ("{:4}").format(kspM.its),  ("{:9}").format("   time: "), ("{:4}").format(time.strftime('%X %x %Z')[0:5])
    uM = uM*scale

    Mits = kspM.its
    kspM.destroy()
    u = IO.arrayToVec(np.concatenate([uNS.array, uM.array]))

    return u,NSits,Mits
def solve(W, P,
          mu,
          u_bcs, p_bcs,
          f,
          verbose=True,
          tol=1.0e-10
          ):
    # Some initial sanity checks.
    assert mu > 0.0

    WP = MixedFunctionSpace([W, P])

    # Translate the boundary conditions into the product space.
    # This conditional loop is able to deal with conditions of the kind
    #
    #     DirichletBC(W.sub(1), 0.0, right_boundary)
    #
    new_bcs = []
    for k, bcs in enumerate([u_bcs, p_bcs]):
        for bc in bcs:
            space = bc.function_space()
            C = space.component()
            if len(C) == 0:
                new_bcs.append(DirichletBC(WP.sub(k),
                                           bc.value(),
                                           bc.domain_args[0]))
            elif len(C) == 1:
                new_bcs.append(DirichletBC(WP.sub(k).sub(int(C[0])),
                                           bc.value(),
                                           bc.domain_args[0]))
            else:
                raise RuntimeError('Illegal number of subspace components.')

    # Define variational problem
    (u, p) = TrialFunctions(WP)
    (v, q) = TestFunctions(WP)

    # Build system.
    # The sign of the div(u)-term is somewhat arbitrary since the right-hand
    # side is 0 here. We can either make the system symmetric or positive-
    # definite.
    # On a second note, we have
    #
    #    \int grad(p).v = - \int p * div(v) + \int_\Gamma p n.v.
    #
    # Since, we have either p=0 or n.v=0 on the boundary, we could as well
    # replace the term dot(grad(p), v) by -p*div(v).
    #
    a = mu * inner(grad(u), grad(v))*dx \
      - p * div(v) * dx \
      - q * div(u) * dx
    #a = mu * inner(grad(u), grad(v))*dx + dot(grad(p), v) * dx \
    #  - div(u) * q * dx
    L = dot(f, v)*dx
    A, b = assemble_system(a, L, new_bcs)

    if has_petsc():
        # For an assortment of preconditioners, see
        #
        #     Performance and analysis of saddle point preconditioners
        #     for the discrete steady-state Navier-Stokes equations;
        #     H.C. Elman, D.J. Silvester, A.J. Wathen;
        #     Numer. Math. (2002) 90: 665-688;
        #     <http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.145.3554>.
        #
        # Set up field split.
        W = SubSpace(WP, 0)
        P = SubSpace(WP, 1)
        u_dofs = W.dofmap().dofs()
        p_dofs = P.dofmap().dofs()
        prec = PETScPreconditioner()
        prec.set_fieldsplit([u_dofs, p_dofs], ['u', 'p'])

        PETScOptions.set('pc_type', 'fieldsplit')
        PETScOptions.set('pc_fieldsplit_type', 'additive')
        PETScOptions.set('fieldsplit_u_pc_type', 'lu')
        PETScOptions.set('fieldsplit_p_pc_type', 'jacobi')

        ## <http://scicomp.stackexchange.com/questions/7288/which-preconditioners-and-solver-in-petsc-for-indefinite-symmetric-systems-sho>
        #PETScOptions.set('pc_type', 'fieldsplit')
        ##PETScOptions.set('pc_fieldsplit_type', 'schur')
        ##PETScOptions.set('pc_fieldsplit_schur_fact_type', 'upper')
        #PETScOptions.set('pc_fieldsplit_detect_saddle_point')
        ##PETScOptions.set('fieldsplit_u_pc_type', 'lsc')
        ##PETScOptions.set('fieldsplit_u_ksp_type', 'preonly')

        #PETScOptions.set('pc_type', 'fieldsplit')
        #PETScOptions.set('fieldsplit_u_pc_type', 'hypre')
        #PETScOptions.set('fieldsplit_u_ksp_type', 'preonly')
        #PETScOptions.set('fieldsplit_p_pc_type', 'jacobi')
        #PETScOptions.set('fieldsplit_p_ksp_type', 'preonly')

        ## From PETSc/src/ksp/ksp/examples/tutorials/ex42-fsschur.opts:
        #PETScOptions.set('pc_type', 'fieldsplit')
        #PETScOptions.set('pc_fieldsplit_type', 'SCHUR')
        #PETScOptions.set('pc_fieldsplit_schur_fact_type', 'UPPER')
        #PETScOptions.set('fieldsplit_p_ksp_type', 'preonly')
        #PETScOptions.set('fieldsplit_u_pc_type', 'bjacobi')

        ## From
        ##
        ##     Composable Linear Solvers for Multiphysics;
        ##     J. Brown, M. Knepley, D.A. May, L.C. McInnes, B. Smith;
        ##     <http://www.computer.org/csdl/proceedings/ispdc/2012/4805/00/4805a055-abs.html>;
        ##     <http://www.mcs.anl.gov/uploads/cels/papers/P2017-0112.pdf>.
        ##
        #PETScOptions.set('pc_type', 'fieldsplit')
        #PETScOptions.set('pc_fieldsplit_type', 'schur')
        #PETScOptions.set('pc_fieldsplit_schur_factorization_type', 'upper')
        ##
        #PETScOptions.set('fieldsplit_u_ksp_type', 'cg')
        #PETScOptions.set('fieldsplit_u_ksp_rtol', 1.0e-6)
        #PETScOptions.set('fieldsplit_u_pc_type', 'bjacobi')
        #PETScOptions.set('fieldsplit_u_sub_pc_type', 'cholesky')
        ##
        #PETScOptions.set('fieldsplit_p_ksp_type', 'fgmres')
        #PETScOptions.set('fieldsplit_p_ksp_constant_null_space')
        #PETScOptions.set('fieldsplit_p_pc_type', 'lsc')
        ##
        #PETScOptions.set('fieldsplit_p_lsc_ksp_type', 'cg')
        #PETScOptions.set('fieldsplit_p_lsc_ksp_rtol', 1.0e-2)
        #PETScOptions.set('fieldsplit_p_lsc_ksp_constant_null_space')
        ##PETScOptions.set('fieldsplit_p_lsc_ksp_converged_reason')
        #PETScOptions.set('fieldsplit_p_lsc_pc_type', 'bjacobi')
        #PETScOptions.set('fieldsplit_p_lsc_sub_pc_type', 'icc')

        # Create Krylov solver with custom preconditioner.
        solver = PETScKrylovSolver('gmres', prec)
        solver.set_operator(A)
    else:
        # Use the preconditioner as recommended in
        # <http://fenicsproject.org/documentation/dolfin/dev/python/demo/pde/stokes-iterative/python/documentation.html>,
        #
        #     prec = inner(grad(u), grad(v))*dx - p*q*dx
        #
        # although it doesn't seem to be too efficient.
        # The sign on the last term doesn't matter.
        prec = mu * inner(grad(u), grad(v))*dx \
             - p*q*dx
        M, _ = assemble_system(prec, L, new_bcs)
        #solver = KrylovSolver('tfqmr', 'amg')
        solver = KrylovSolver('gmres', 'amg')
        solver.set_operators(A, M)

    solver.parameters['monitor_convergence'] = verbose
    solver.parameters['report'] = verbose
    solver.parameters['absolute_tolerance'] = 0.0
    solver.parameters['relative_tolerance'] = tol
    solver.parameters['maximum_iterations'] = 500

    # Solve
    up = Function(WP)
    solver.solve(up.vector(), b)

    # Get sub-functions
    u, p = up.split()

    return u, p
Exemple #18
0
def RunJob(Tb, mu_value, path):
    runtimeInit = clock()

    tfile = File(path + '/t6t.pvd')
    mufile = File(path + "/mu.pvd")
    ufile = File(path + '/velocity.pvd')
    gradpfile = File(path + '/gradp.pvd')
    pfile = File(path + '/pstar.pvd')
    parameters = open(path + '/parameters', 'w', 0)
    vmeltfile = File(path + '/vmelt.pvd')
    rhofile = File(path + '/rhosolid.pvd')

    for name in dir():
        ev = str(eval(name))
        if name[0] != '_' and ev[0] != '<':
            parameters.write(name + ' = ' + ev + '\n')

    temp_values = [27. + 273, Tb + 273, 1300. + 273, 1305. + 273]
    dTemp = temp_values[3] - temp_values[0]
    temp_values = [x / dTemp for x in temp_values]  # non dimensionalising temp

    mu_a = mu_value  # this was taken from the blankenbach paper, can change..

    Ep = b / dTemp

    mu_bot = exp(-Ep * (temp_values[3] * dTemp - 1573) + cc) * mu_a

    Ra = rho_0 * alpha * g * dTemp * h**3 / (kappa_0 * mu_a)
    w0 = rho_0 * alpha * g * dTemp * h**2 / mu_a
    tau = h / w0
    p0 = mu_a * w0 / h

    print(mu_a, mu_bot, Ra, w0, p0)

    vslipx = 1.6e-09 / w0
    vslip = Constant((vslipx, 0.0))  # nondimensional
    noslip = Constant((0.0, 0.0))

    dt = 3.E11 / tau
    tEnd = 3.E13 / tau  # non-dimensionalising times

    class PeriodicBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return left(x, on_boundary)

        def map(self, x, y):
            y[0] = x[0] - MeshWidth
            y[1] = x[1]

    pbc = PeriodicBoundary()

    class TempExp(Expression):
        def eval(self, value, x):
            if x[1] >= LAB(x):
                value[0] = temp_values[0] + (temp_values[1] - temp_values[0]
                                             ) * (MeshHeight -
                                                  x[1]) / (MeshHeight - LAB(x))
            else:
                value[0] = temp_values[3] - (
                    temp_values[3] - temp_values[2]) * (x[1]) / (LAB(x))

    class FluidTemp(Expression):
        def eval(self, value, x):
            if value[0] < 1295:
                value[0] = 1295

    mesh = RectangleMesh(Point(0.0, 0.0), Point(MeshWidth, MeshHeight), nx, ny)

    Svel = VectorFunctionSpace(mesh, 'CG', 2, constrained_domain=pbc)
    Spre = FunctionSpace(mesh, 'CG', 1, constrained_domain=pbc)
    Stemp = FunctionSpace(mesh, 'CG', 1, constrained_domain=pbc)
    Smu = FunctionSpace(mesh, 'CG', 1, constrained_domain=pbc)
    Sgradp = VectorFunctionSpace(mesh, 'CG', 2, constrained_domain=pbc)
    Srho = FunctionSpace(mesh, 'CG', 1, constrained_domain=pbc)
    S0 = MixedFunctionSpace([Svel, Spre, Stemp])

    u = Function(S0)
    v, p, T = split(u)
    v_t, p_t, T_t = TestFunctions(S0)

    T0 = interpolate(TempExp(), Stemp)

    muExp = Expression(
        'exp(-Ep * (T_val * dTemp - 1573) + cc * x[2] / meshHeight)',
        Smu.ufl_element(),
        Ep=Ep,
        dTemp=dTemp,
        cc=cc,
        meshHeight=MeshHeight,
        T_val=T0)

    mu = interpolate(muExp, Smu)

    rhosolid = Function(Srho)
    deltarho = Function(Srho)

    v0 = Function(Svel)
    vmelt = Function(Svel)

    v_theta = (1. - theta) * v0 + theta * v

    T_theta = (1. - theta) * T + theta * T0

    r_v = (inner(sym(grad(v_t)), 2.*mu*sym(grad(v))) \
        - div(v_t)*p \
        - T*v_t[1] )*dx

    r_p = p_t * div(v) * dx

    r_T = (T_t*((T - T0) \
        + dt*inner(v_theta, grad(T_theta))) \
        + (dt/Ra)*inner(grad(T_t), grad(T_theta)) )*dx
    #           + k_s*(Tf-T_theta)*dt

    Tf = T0.interpolate(FluidTemp())
    # Tf = T0.interpolate(Expression('value[0] >= 1295.0 ? value[0] : 1295.0'))

    # Tf.interpolate(Expression('value[0] >= 1295 ? value[0] : 1295'))
    # project(Expression('value[0] >= 1295 ? value[0] : 1295'), Tf)
    # Alex, a question for you:
    # can you see if there is a way to set Tf = T in regions where T >=1295 celsius
    #
    # 1295 celsius is my arbitrary choice for the LAB isotherm.  In regions
    # where T < 1295 C, set Tf to be some constant for now, such as 1295 C.
    # Once we do this, then we can add in a term like that last line above where
    # it will only be non-zero when the solid temperature, T, is cooler than 1295
    # can you do this? After this is done, we will then worry about a calculation
    # where we solve for Tf as a function of time in the regions cooler than 1295 C
    # Makes sense?  If not, we can skype soon -- email me with questions
    # 3/19/16
    r = r_v + r_p + r_T

    bcv0 = DirichletBC(S0.sub(0), noslip, top)
    bcv1 = DirichletBC(S0.sub(0), vslip, bottom)
    bcp0 = DirichletBC(S0.sub(1), Constant(0.0), bottom)
    bct0 = DirichletBC(S0.sub(2), Constant(temp_values[0]), top)
    bct1 = DirichletBC(S0.sub(2), Constant(temp_values[3]), bottom)

    bcs = [bcv0, bcv1, bcp0, bct0, bct1]

    t = 0
    count = 0
    while (t < tEnd):
        solve(r == 0, u, bcs)
        t += dt
        nV, nP, nT = u.split()
        gp = grad(nP)
        rhosolid = rho_0 * (1 - alpha * (nT * dTemp - 1573))
        deltarho = rhosolid - rhomelt
        yvec = Constant((0.0, 1.0))
        vmelt = nV * w0 - darcy * (gp * p0 / h - deltarho * yvec * g)
        if (count % 100 == 0):
            pfile << nP
            ufile << nV
            tfile << nT
            mufile << mu
            gradpfile << project(grad(nP), Sgradp)
            mufile << project(mu * mu_a, Smu)
            rhofile << project(rhosolid, Srho)
            vmeltfile << project(vmelt, Svel)
        count += 1
        assign(T0, nT)
        assign(v0, nV)
        mu.interpolate(muExp)

    print('Case mu=%g, Tb=%g complete.' % (mu_a, Tb), ' Run time =',
          clock() - runtimeInit, 's')
Exemple #19
0
def lid_driven_cavity():
    n = 40
    mesh = RectangleMesh(0.0, 0.0, 1.0, 1.0, n, n, "crossed")

    # Define mesh and boundaries.
    class LeftBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[0] < DOLFIN_EPS

    class RightBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[0] > 1.0 - DOLFIN_EPS

    class LowerBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[1] < DOLFIN_EPS

    class UpperBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[1] > 1.0 - DOLFIN_EPS

    class RestrictedUpperBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return (
                on_boundary
                and x[1] > 1.0 - DOLFIN_EPS
                and DOLFIN_EPS < x[0]
                and x[0] < 0.5 - DOLFIN_EPS
            )

    left = LeftBoundary()
    right = RightBoundary()
    lower = LowerBoundary()
    upper = UpperBoundary()
    # restricted_upper = RestrictedUpperBoundary()

    V = FunctionSpace(mesh, "CG", 2)

    # Be particularly careful with the boundary conditions.
    # The main problem here is that the PPE system is consistent if and only
    # if
    #
    #     \int_\Omega div(u) = \int_\Gamma n.u = 0.
    #
    # This is exactly and even pointwise fulfilled for the continuous problem.
    # In the discrete case, we can have to make sure that n.u is 0 all along
    # the boundary.
    # In the lid-driven cavity problem, of particular interest are the corner
    # points at the lid. One has to assert that the z-component of u is 0 all
    # across the lid, and the x-component of u is 0 everywhere but the lid.
    # Since u is L2-"continuous", the lid condition on u_x must not be enforced
    # in the corner points. The u_y component must be enforced all over the
    # lid, including the end points.
    W = MixedFunctionSpace([V, V])
    u_bcs = [
        DirichletBC(W, (0.0, 0.0), left),
        DirichletBC(W, (0.0, 0.0), right),
        # DirichletBC(W.sub(0), Expression('x[0]'), restricted_upper),
        DirichletBC(W, (0.0, 0.0), lower),
        DirichletBC(W.sub(0), Constant("1.0"), upper),
        DirichletBC(W.sub(1), 0.0, upper),
        # DirichletBC(W.sub(0), Constant('-1.0'), lower),
        # DirichletBC(W.sub(1), 0.0, lower),
        # DirichletBC(W.sub(1), Constant('1.0'), left),
        # DirichletBC(W.sub(0), 0.0, left),
        # DirichletBC(W.sub(1), Constant('-1.0'), right),
        # DirichletBC(W.sub(0), 0.0, right),
    ]
    P = FunctionSpace(mesh, "CG", 1)
    p_bcs = []
    return mesh, W, P, u_bcs, p_bcs
Exemple #20
0
    def solve(self, problem):
        self.problem = problem
        doSave = problem.doSave
        save_this_step = False
        onlyVel = problem.saveOnlyVel
        dt = self.metadata['dt']

        nu = Constant(self.problem.nu)
        self.tc.init_watch('init',
                           'Initialization',
                           True,
                           count_to_percent=False)
        self.tc.init_watch('solve',
                           'Running nonlinear solver',
                           True,
                           count_to_percent=True)
        self.tc.init_watch('next',
                           'Next step assignments',
                           True,
                           count_to_percent=True)
        self.tc.init_watch('saveVel', 'Saved velocity', True)

        self.tc.start('init')

        mesh = self.problem.mesh

        # Define function spaces (P2-P1)
        self.V = VectorFunctionSpace(mesh, "Lagrange", 2)  # velocity
        self.Q = FunctionSpace(mesh, "Lagrange", 1)  # pressure
        self.W = MixedFunctionSpace([self.V, self.Q])
        self.PS = FunctionSpace(
            mesh, "Lagrange", 2)  # partial solution (must be same order as V)
        self.D = FunctionSpace(mesh, "Lagrange",
                               1)  # velocity divergence space

        # to assign solution in space W.sub(0) to Function(V) we need FunctionAssigner (cannot be assigned directly)
        fa = FunctionAssigner(self.V, self.W.sub(0))
        velSp = Function(self.V)

        problem.initialize(self.V, self.Q, self.PS, self.D)

        # Define unknown and test function(s) NS
        v, q = TestFunctions(self.W)
        w = Function(self.W)
        dw = TrialFunction(self.W)
        u, p = split(w)

        # Define fields
        n = FacetNormal(mesh)
        I = Identity(u.geometric_dimension())
        theta = 0.5  # Crank-Nicholson
        k = Constant(self.metadata['dt'])

        # Initial conditions: u0 velocity at previous time step u1 velocity two time steps back p0 previous pressure
        [u0, p0] = self.problem.get_initial_conditions([{
            'type': 'v',
            'time': 0.0
        }, {
            'type': 'p',
            'time': 0.0
        }])

        if doSave:
            problem.save_vel(False, u0)

        # boundary conditions
        bcu, bcp = problem.get_boundary_conditions(False, self.W.sub(0),
                                                   self.W.sub(1))

        # Define steady part of the equation
        def T(u):
            return -p * I + 2.0 * nu * sym(grad(u))

        def F(u, v, q):
            return (inner(T(u), grad(v)) - q * div(u)) * dx + inner(
                grad(u) * u, v) * dx

        # Define variational forms
        F_ns = (inner(
            (u - u0), v) / k) * dx + (1.0 - theta) * F(u0, v, q) + theta * F(
                u, v, q)
        J_ns = derivative(F_ns, w, dw)
        # J_ns = derivative(F_ns, w)  # did not work

        # NS_problem = NonlinearVariationalProblem(F_ns, w, bcu, J_ns, form_compiler_parameters=ffc_options)
        NS_problem = NonlinearVariationalProblem(F_ns, w, bcu, J_ns)
        # (var. formulation, unknown, Dir. BC, jacobian, optional)
        NS_solver = NonlinearVariationalSolver(NS_problem)

        prm = NS_solver.parameters
        prm['newton_solver']['absolute_tolerance'] = 1E-08
        prm['newton_solver']['relative_tolerance'] = 1E-08
        # prm['newton_solver']['maximum_iterations'] = 45
        # prm['newton_solver']['relaxation_parameter'] = 1.0
        prm['newton_solver']['linear_solver'] = 'mumps'
        # prm['newton_solver']['lu_solver']['same_nonzero_pattern'] = True

        info(NS_solver.parameters, True)

        self.tc.end('init')

        # Time-stepping
        info("Running of direct method")
        ttime = self.metadata['time']
        t = dt
        step = 1
        while t < (ttime + dt / 2.0):
            self.problem.update_time(t, step)
            if self.MPI_rank == 0:
                problem.write_status_file(t)

            if doSave:
                save_this_step = problem.save_this_step

            # Compute
            begin("Solving NS ....")
            try:
                self.tc.start('solve')
                NS_solver.solve()
                self.tc.end('solve')
            except RuntimeError as inst:
                problem.report_fail(t)
                return 1
            end()

            # Extract solutions:
            (u, p) = w.split()
            fa.assign(velSp, u)
            # we are assigning twice (now and inside save_vel), but it works with one method save_vel for direct and
            #   projection (we could split save_vel to save one assign)

            if save_this_step:
                self.tc.start('saveVel')
                problem.save_vel(False, velSp)
                self.tc.end('saveVel')
            if save_this_step and not onlyVel:
                problem.save_div(False, u)
            problem.compute_err(False, u, t)
            problem.compute_div(False, u)

            # foo = Function(self.Q)
            # foo.assign(p)
            # problem.averaging_pressure(foo)
            # if save_this_step and not onlyVel:
            #     problem.save_pressure(False, foo)

            if save_this_step and not onlyVel:
                problem.save_pressure(False, p)

            # compute functionals (e. g. forces)
            problem.compute_functionals(u, p, t, step)

            # Move to next time step
            self.tc.start('next')
            u0.assign(velSp)
            t = round(t + dt, 6)  # round time step to 0.000001
            step += 1
            self.tc.end('next')

        info("Finished: direct method")
        problem.report()
        return 0
Exemple #21
0
def lid_driven_cavity():
    n = 40
    mesh = RectangleMesh(0.0, 0.0, 1.0, 1.0, n, n, 'crossed')

    # Define mesh and boundaries.
    class LeftBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[0] < DOLFIN_EPS

    class RightBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[0] > 1.0-DOLFIN_EPS

    class LowerBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[1] < DOLFIN_EPS

    class UpperBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[1] > 1.0-DOLFIN_EPS

    class RestrictedUpperBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and x[1] > 1.0-DOLFIN_EPS \
                and DOLFIN_EPS < x[0] and x[0] < 0.5-DOLFIN_EPS

    left = LeftBoundary()
    right = RightBoundary()
    lower = LowerBoundary()
    upper = UpperBoundary()
    # restricted_upper = RestrictedUpperBoundary()

    V = FunctionSpace(mesh, 'CG', 2)

    # Be particularly careful with the boundary conditions.
    # The main problem here is that the PPE system is consistent if and only
    # if
    #
    #     \int_\Omega div(u) = \int_\Gamma n.u = 0.
    #
    # This is exactly and even pointwise fulfilled for the continuous problem.
    # In the discrete case, we can have to make sure that n.u is 0 all along
    # the boundary.
    # In the lid-driven cavity problem, of particular interest are the corner
    # points at the lid. One has to assert that the z-component of u is 0 all
    # across the lid, and the x-component of u is 0 everywhere but the lid.
    # Since u is L2-"continuous", the lid condition on u_x must not be enforced
    # in the corner points. The u_y component must be enforced all over the
    # lid, including the end points.
    W = MixedFunctionSpace([V, V])
    u_bcs = [
        DirichletBC(W, (0.0, 0.0), left),
        DirichletBC(W, (0.0, 0.0), right),
        #DirichletBC(W.sub(0), Expression('x[0]'), restricted_upper),
        DirichletBC(W, (0.0, 0.0), lower),
        DirichletBC(W.sub(0), Constant('1.0'), upper),
        DirichletBC(W.sub(1), 0.0, upper),
        #DirichletBC(W.sub(0), Constant('-1.0'), lower),
        #DirichletBC(W.sub(1), 0.0, lower),
        #DirichletBC(W.sub(1), Constant('1.0'), left),
        #DirichletBC(W.sub(0), 0.0, left),
        #DirichletBC(W.sub(1), Constant('-1.0'), right),
        #DirichletBC(W.sub(0), 0.0, right),
        ]
    P = FunctionSpace(mesh, 'CG', 1)
    p_bcs = []
    return mesh, W, P, u_bcs, p_bcs

v1 = Constant((1.0, 0.0))
v2 = Constant((-1.0, 0.0))

def left(x, on_boundary):
    return on_boundary and near(x[0], 0.0)

def right(x, on_boundary):
    return on_boundary and near(x[0], 1.0)

mesh = RectangleMesh(Point(0.0, 0.0), Point(1.0, 1.0), 50, 50)
dt = 0.01

S = FunctionSpace(mesh, 'CG', 1)
W = MixedFunctionSpace([S, S])
u = Function(W)

T, Tf = split(u)
# T, Tf = TrialFunctions(W)
T_t, Tf_t = TestFunctions(W)

T0 = interpolate(Expression('1.0 / (10.0 * x[0] + 1.0)'), S)
Tf0 = interpolate(Expression('1.0 / (10.0 * (1.0 - x[0]) + 1.0)'), S)

heat_transfer = 10.0 * (Tf - T) * dt

r_1 = T_t * (
    (T - T0)
    + dt * dot(v1, grad(T))
    - heat_transfer) * dx
Exemple #23
0
def run_with_params(Tb, mu_value, k_s, path):
    run_time_init = clock()

    temperature_vals = [27.0 + 273, Tb + 273, 1300.0 + 273, 1305.0 + 273]
    temp_prof = TemperatureProfile(temperature_vals)

    mu_a = mu_value  # this was taken from the Blankenbach paper, can change

    Ep = b / temp_prof.delta

    mu_bot = exp(-Ep *
                 (temp_prof.bottom * temp_prof.delta - 1573.0) + cc) * mu_a

    Ra = rho_0 * alpha * g * temp_prof.delta * h**3 / (kappa_0 * mu_a)
    w0 = rho_0 * alpha * g * temp_prof.delta * h**2 / mu_a
    tau = h / w0
    p0 = mu_a * w0 / h

    log(mu_a, mu_bot, Ra, w0, p0)

    vslipx = 1.6e-09 / w0
    vslip = Constant((vslipx, 0.0))  # Non-dimensional
    noslip = Constant((0.0, 0.0))

    time_step = 3.0E11 / tau / 10.0

    dt = Constant(time_step)
    tEnd = 3.0E15 / tau / 5.0  # Non-dimensionalising times

    mesh = RectangleMesh(Point(0.0, 0.0), Point(mesh_width, mesh_height), nx,
                         ny)

    pbc = PeriodicBoundary()
    W = VectorFunctionSpace(mesh, 'CG', 2, constrained_domain=pbc)
    S = FunctionSpace(mesh, 'CG', 1, constrained_domain=pbc)
    WSSS = MixedFunctionSpace([W, S, S, S])  # WSSS -> W

    u = Function(WSSS)

    # Instead of TrialFunctions, we use split(u) for our non-linear problem
    v, p, T, Tf = split(u)
    v_t, p_t, T_t, Tf_t = TestFunctions(WSSS)

    T0 = interpolate(temp_prof, S)

    FluidTemp = Expression('max(T0, 1.031)', T0=T0)

    muExp = Expression(
        'exp(-Ep * (T_val * dTemp - 1573.0) + cc * x[1] / mesh_height)',
        Ep=Ep,
        dTemp=temp_prof.delta,
        cc=cc,
        mesh_height=mesh_height,
        T_val=T0)

    Tf0 = interpolate(temp_prof, S)

    mu = Function(S)
    v0 = Function(W)

    v_theta = (1.0 - theta) * v0 + theta * v

    T_theta = (1.0 - theta) * T0 + theta * T

    Tf_theta = (1.0 - theta) * Tf0 + theta * Tf

    r_v = (inner(sym(grad(v_t)), 2.0 * mu * sym(grad(v))) - div(v_t) * p -
           T * v_t[1]) * dx

    r_p = p_t * div(v) * dx

    heat_transfer = k_s * (Tf_theta - T_theta) * dt

    r_T = (T_t * ((T - T0) + dt * inner(v_theta, grad(T_theta))) +
           (dt / Ra) * inner(grad(T_t), grad(T_theta)) -
           T_t * heat_transfer) * dx

    # yvec = Constant((0.0, 1.0))
    # rhosolid = rho_0 * (1.0 - alpha * (T_theta * temp_prof.delta - 1573.0))
    # deltarho = rhosolid - rhomelt
    # v_f = v_theta - darcy * (grad(p) * p0 / h - deltarho * yvec * g) / w0

    v_melt = Function(W)
    yvec = Constant((0.0, 1.0))

    # TODO: inner -> dot, take out Tf_t
    r_Tf = (Tf_t * ((Tf - Tf0) + dt * dot(v_melt, grad(Tf_theta))) +
            Tf_t * heat_transfer) * dx

    r = r_v + r_p + r_T + r_Tf

    bcv0 = DirichletBC(WSSS.sub(0), noslip, top)
    bcv1 = DirichletBC(WSSS.sub(0), vslip, bottom)
    bcp0 = DirichletBC(WSSS.sub(1), Constant(0.0), bottom)
    bct0 = DirichletBC(WSSS.sub(2), Constant(temp_prof.surface), top)
    bct1 = DirichletBC(WSSS.sub(2), Constant(temp_prof.bottom), bottom)
    bctf1 = DirichletBC(WSSS.sub(3), Constant(temp_prof.bottom), bottom)

    bcs = [bcv0, bcv1, bcp0, bct0, bct1, bctf1]

    t = 0
    count = 0
    files = DefaultDictByKey(partial(create_xdmf, path))

    while t < tEnd:
        mu.interpolate(muExp)
        rhosolid = rho_0 * (1.0 - alpha * (T0 * temp_prof.delta - 1573.0))
        deltarho = rhosolid - rhomelt
        assign(
            v_melt,
            project(v0 - darcy * (grad(p) * p0 / h - deltarho * yvec * g) / w0,
                    W))
        # use nP after to avoid projection?
        # pdb.set_trace()

        solve(r == 0, u, bcs)
        nV, nP, nT, nTf = u.split()

        if count % output_every == 0:
            time_left(count, tEnd / time_step, run_time_init)

            # TODO: Make sure all writes are to the same function for each time step
            files['T_fluid'].write(nTf)
            files['p'].write(nP)
            files['v_solid'].write(nV)
            files['T_solid'].write(nT)
            files['mu'].write(mu)
            files['v_melt'].write(v_melt)
            files['gradp'].write(project(grad(nP), W))
            files['rho'].write(project(rhosolid, S))
            files['Tf_grad'].write(project(grad(Tf), W))
            files['advect'].write(project(dt * dot(v_melt, grad(nTf))))
            files['ht'].write(project(heat_transfer, S))

        assign(T0, nT)
        assign(v0, nV)
        assign(Tf0, nTf)

        t += time_step
        count += 1

    log('Case mu=%g, Tb=%g complete. Run time = %g s' %
        (mu_a, Tb, clock() - run_time_init))
Exemple #24
0
def solve(A, b, u, params, Fspace, SolveType, IterType, OuterTol, InnerTol,
          HiptmairMatrices, Hiptmairtol, KSPlinearfluids, Fp, kspF):

    if SolveType == "Direct":
        ksp = PETSc.KSP()
        ksp.create(comm=PETSc.COMM_WORLD)
        pc = ksp.getPC()
        ksp.setType('preonly')
        pc.setType('lu')
        OptDB = PETSc.Options()
        OptDB['pc_factor_mat_solver_package'] = "mumps"
        OptDB['pc_factor_mat_ordering_type'] = "rcm"
        ksp.setFromOptions()
        scale = b.norm()
        b = b / scale
        ksp.setOperators(A, A)
        del A
        ksp.solve(b, u)
        # Mits +=dodim
        u = u * scale
        MO.PrintStr("Number iterations = " + str(ksp.its), 60, "+", "\n\n",
                    "\n\n")
        return u, ksp.its, 0
    elif SolveType == "Direct-class":
        ksp = PETSc.KSP()
        ksp.create(comm=PETSc.COMM_WORLD)
        pc = ksp.getPC()
        ksp.setType('gmres')
        pc.setType('none')
        ksp.setFromOptions()
        scale = b.norm()
        b = b / scale
        ksp.setOperators(A, A)
        del A
        ksp.solve(b, u)
        # Mits +=dodim
        u = u * scale
        MO.PrintStr("Number iterations = " + str(ksp.its), 60, "+", "\n\n",
                    "\n\n")
        return u, ksp.its, 0

    else:

        # u = b.duplicate()
        if IterType == "Full":
            ksp = PETSc.KSP()
            ksp.create(comm=PETSc.COMM_WORLD)
            pc = ksp.getPC()
            ksp.setType('fgmres')
            pc.setType('python')
            OptDB = PETSc.Options()
            OptDB['ksp_gmres_restart'] = 200
            # FSpace = [Velocity,Magnetic,Pressure,Lagrange]
            reshist = {}

            def monitor(ksp, its, fgnorm):
                reshist[its] = fgnorm
                print its, "    OUTER:", fgnorm

            # ksp.setMonitor(monitor)
            ksp.max_it = 1000
            W = Fspace
            FFSS = [W.sub(0), W.sub(1), W.sub(2), W.sub(3)]
            pc.setPythonContext(
                MHDprec.InnerOuterMAGNETICapprox(
                    FFSS, kspF, KSPlinearfluids[0], KSPlinearfluids[1], Fp,
                    HiptmairMatrices[3], HiptmairMatrices[4],
                    HiptmairMatrices[2], HiptmairMatrices[0],
                    HiptmairMatrices[1], HiptmairMatrices[6], Hiptmairtol))
            #OptDB = PETSc.Options()

            # OptDB['pc_factor_mat_solver_package']  = "mumps"
            # OptDB['pc_factor_mat_ordering_type']  = "rcm"
            # ksp.setFromOptions()
            scale = b.norm()
            b = b / scale
            ksp.setOperators(A, A)
            del A
            ksp.solve(b, u)
            # Mits +=dodim
            u = u * scale
            MO.PrintStr("Number iterations = " + str(ksp.its), 60, "+", "\n\n",
                        "\n\n")
            return u, ksp.its, 0

        IS = MO.IndexSet(Fspace, '2by2')
        M_is = IS[1]
        NS_is = IS[0]
        kspNS = PETSc.KSP().create()
        kspM = PETSc.KSP().create()
        kspNS.setTolerances(OuterTol)

        kspNS.setOperators(A[0])
        kspM.setOperators(A[1])
        # print P.symmetric
        if IterType == "MD":
            kspNS.setType('gmres')
            kspNS.max_it = 500

            pcNS = kspNS.getPC()
            pcNS.setType(PETSc.PC.Type.PYTHON)
            pcNS.setPythonContext(
                NSpreconditioner.NSPCD(
                    MixedFunctionSpace([Fspace.sub(0),
                                        Fspace.sub(1)]), kspF,
                    KSPlinearfluids[0], KSPlinearfluids[1], Fp))
        elif IterType == "CD":
            kspNS.setType('minres')
            pcNS = kspNS.getPC()
            pcNS.setType(PETSc.PC.Type.PYTHON)
            Q = KSPlinearfluids[1].getOperators()[0]
            Q = 1. / params[2] * Q
            KSPlinearfluids[1].setOperators(Q, Q)
            pcNS.setPythonContext(
                StokesPrecond.MHDApprox(
                    MixedFunctionSpace([Fspace.sub(0),
                                        Fspace.sub(1)]), kspF,
                    KSPlinearfluids[1]))
        reshist = {}

        def monitor(ksp, its, fgnorm):
            reshist[its] = fgnorm
            print fgnorm

        # kspNS.setMonitor(monitor)

        uNS = u.getSubVector(NS_is)
        bNS = b.getSubVector(NS_is)
        # print kspNS.view()
        scale = bNS.norm()
        bNS = bNS / scale
        print bNS.norm()
        kspNS.solve(bNS, uNS)
        uNS = uNS * scale
        NSits = kspNS.its
        kspNS.destroy()
        # for line in reshist.values():
        #     print line
        kspM.setFromOptions()
        kspM.setType(kspM.Type.MINRES)
        kspM.setTolerances(InnerTol)
        pcM = kspM.getPC()
        pcM.setType(PETSc.PC.Type.PYTHON)
        pcM.setPythonContext(
            MP.Hiptmair(MixedFunctionSpace([Fspace.sub(2),
                                            Fspace.sub(3)]),
                        HiptmairMatrices[3], HiptmairMatrices[4],
                        HiptmairMatrices[2], HiptmairMatrices[0],
                        HiptmairMatrices[1], HiptmairMatrices[6], Hiptmairtol))

        uM = u.getSubVector(M_is)
        bM = b.getSubVector(M_is)
        scale = bM.norm()
        bM = bM / scale
        print bM.norm()
        kspM.solve(bM, uM)
        uM = uM * scale
        Mits = kspM.its
        kspM.destroy()
        u = IO.arrayToVec(np.concatenate([uNS.array, uM.array]))

        MO.PrintStr("Number of M iterations = " + str(Mits), 60, "+", "\n\n",
                    "\n\n")
        MO.PrintStr("Number of NS/S iterations = " + str(NSits), 60, "+",
                    "\n\n", "\n\n")
        return u, NSits, Mits
def RunJob(Tb, mu_value, path):
    runtimeInit = clock()

    tfile = File(path + '/t6t.pvd')
    mufile = File(path + "/mu.pvd")
    ufile = File(path + '/velocity.pvd')
    gradpfile = File(path + '/gradp.pvd')
    pfile = File(path + '/pstar.pvd')
    parameters = open(path + '/parameters', 'w', 0)
    vmeltfile = File(path + '/vmelt.pvd')
    rhofile = File(path + '/rhosolid.pvd')

    for name in dir():
        ev = str(eval(name))
        if name[0] != '_' and ev[0] != '<':
            parameters.write(name + ' = ' + ev + '\n')

    temp_values = [27. + 273, Tb + 273, 1300. + 273, 1305. + 273]
    dTemp = temp_values[3] - temp_values[0]
    temp_values = [x / dTemp for x in temp_values]  # non dimensionalising temp

    mu_a = mu_value  # this was taken from the blankenbach paper, can change..
    
    Ep = b / dTemp

    mu_bot = exp(-Ep * (temp_values[3] * dTemp - 1573) + cc) * mu_a

    Ra = rho_0 * alpha * g * dTemp * h**3 / (kappa_0 * mu_a)
    w0 = rho_0 * alpha * g * dTemp * h**2 / mu_a
    tau = h / w0
    p0 = mu_a * w0 / h

    print(mu_a, mu_bot, Ra, w0, p0)

    vslipx = 1.6e-09 / w0
    vslip = Constant((vslipx, 0.0))  # nondimensional
    noslip = Constant((0.0, 0.0))

    dt = 3.E11 / tau
    tEnd = 3.E13 / tau  # non-dimensionalising times

    class PeriodicBoundary(SubDomain):
        def inside(self, x, on_boundary):
            return left(x, on_boundary)

        def map(self, x, y):
            y[0] = x[0] - MeshWidth
            y[1] = x[1]

    pbc = PeriodicBoundary()

    class TempExp(Expression):
        def eval(self, value, x):
            if x[1] >= LAB(x):
                value[0] = temp_values[0] + (temp_values[1] - temp_values[0]) * (MeshHeight - x[1]) / (MeshHeight - LAB(x))
            else:
                value[0] = temp_values[3] - (temp_values[3] - temp_values[2]) * (x[1]) / (LAB(x))

    class FluidTemp(Expression):
        def eval(self, value, x):
            if value[0] < 1295:
                value[0] = 1295

    mesh = RectangleMesh(Point(0.0, 0.0), Point(MeshWidth, MeshHeight), nx, ny)

    Svel = VectorFunctionSpace(mesh, 'CG', 2, constrained_domain=pbc)
    Spre = FunctionSpace(mesh, 'CG', 1, constrained_domain=pbc)
    Stemp = FunctionSpace(mesh, 'CG', 1, constrained_domain=pbc)
    Smu = FunctionSpace(mesh, 'CG', 1, constrained_domain=pbc)
    Sgradp = VectorFunctionSpace(mesh, 'CG', 2, constrained_domain=pbc)
    Srho = FunctionSpace(mesh, 'CG', 1, constrained_domain=pbc)
    S0 = MixedFunctionSpace([Svel, Spre, Stemp])

    u = Function(S0)
    v, p, T = split(u)
    v_t, p_t, T_t = TestFunctions(S0)

    T0 = interpolate(TempExp(), Stemp)

    muExp = Expression('exp(-Ep * (T_val * dTemp - 1573) + cc * x[2] / meshHeight)', Smu.ufl_element(),
                        Ep=Ep, dTemp=dTemp, cc=cc, meshHeight=MeshHeight, T_val=T0)

    mu = interpolate(muExp, Smu)

    rhosolid = Function(Srho)
    deltarho = Function(Srho)

    v0 = Function(Svel)
    vmelt = Function(Svel)

    v_theta = (1. - theta)*v0 + theta*v

    T_theta = (1. - theta)*T + theta*T0

    r_v = (inner(sym(grad(v_t)), 2.*mu*sym(grad(v))) \
        - div(v_t)*p \
        - T*v_t[1] )*dx

    r_p = p_t*div(v)*dx

    r_T = (T_t*((T - T0) \
        + dt*inner(v_theta, grad(T_theta))) \
        + (dt/Ra)*inner(grad(T_t), grad(T_theta)) )*dx
#           + k_s*(Tf-T_theta)*dt

    Tf = T0.interpolate(FluidTemp())
    # Tf = T0.interpolate(Expression('value[0] >= 1295.0 ? value[0] : 1295.0'))

    # Tf.interpolate(Expression('value[0] >= 1295 ? value[0] : 1295'))
    # project(Expression('value[0] >= 1295 ? value[0] : 1295'), Tf)
# Alex, a question for you:
# can you see if there is a way to set Tf = T in regions where T >=1295 celsius
#
# 1295 celsius is my arbitrary choice for the LAB isotherm.  In regions
# where T < 1295 C, set Tf to be some constant for now, such as 1295 C.
# Once we do this, then we can add in a term like that last line above where
# it will only be non-zero when the solid temperature, T, is cooler than 1295
# can you do this? After this is done, we will then worry about a calculation
# where we solve for Tf as a function of time in the regions cooler than 1295 C
# Makes sense?  If not, we can skype soon -- email me with questions
# 3/19/16
    r = r_v + r_p + r_T

    bcv0 = DirichletBC(S0.sub(0), noslip, top)
    bcv1 = DirichletBC(S0.sub(0), vslip, bottom)
    bcp0 = DirichletBC(S0.sub(1), Constant(0.0), bottom)
    bct0 = DirichletBC(S0.sub(2), Constant(temp_values[0]), top)
    bct1 = DirichletBC(S0.sub(2), Constant(temp_values[3]), bottom)

    bcs = [bcv0, bcv1, bcp0, bct0, bct1]

    t = 0
    count = 0
    while (t < tEnd):
        solve(r == 0, u, bcs)
        t += dt
        nV, nP, nT = u.split()
        gp = grad(nP)
        rhosolid = rho_0 * (1 - alpha * (nT * dTemp - 1573))
        deltarho = rhosolid - rhomelt
        yvec = Constant((0.0, 1.0))
        vmelt = nV * w0 - darcy * (gp * p0 / h - deltarho * yvec * g)
        if (count % 100 == 0):
            pfile << nP
            ufile << nV
            tfile << nT
            mufile << mu
            gradpfile << project(grad(nP), Sgradp)
            mufile << project(mu * mu_a, Smu)
            rhofile << project(rhosolid, Srho)
            vmeltfile << project(vmelt, Svel)
        count += 1
        assign(T0, nT)
        assign(v0, nV)
        mu.interpolate(muExp)

    print('Case mu=%g, Tb=%g complete.' % (mu_a, Tb), ' Run time =', clock() - runtimeInit, 's')