Example #1
0
 def get_N_form(self):
     try:
         return self.N_form
     except AttributeError:
         pass
     # Set up magnetic field and equivalent electric current forms
     H_r = -curl(self.E_i)/(self.k0*Z0)
     H_i = curl(self.E_r)/(self.k0*Z0)
     J_r = cross(self.n, H_r)
     J_i = cross(self.n, H_i)
     #------------------------------
     # Set up form for far field potential N
     theta_hat = self.theta_hat
     phi_hat = self.phi_hat
     phase = self.phase
     N_r = J_r*dolfin.cos(phase) - J_i*dolfin.sin(phase)
     N_i = J_r*dolfin.sin(phase) + J_i*dolfin.cos(phase)
     # UFL does not seem to like vector valued functionals, so we split the
     # final functional from into theta and phi components
     self.N_form = dict(
         r_theta=dot(theta_hat, N_r)*ds,
         r_phi=dot(phi_hat, N_r)*ds,
         i_theta=dot(theta_hat, N_i)*ds,
         i_phi=dot(phi_hat, N_i)*ds)
     return self.N_form
Example #2
0
 def neumann_linear_form(self, V, neumann_boundary, g, L=None):
     """Return or add up the linear form L(v) coming from the Neumann boundary"""
     v = dolfin.TrialFunction(V)
     for g_j, ds_j in self.neumann_form_list(neumann_boundary, g, V.mesh()):
         if L is None:
             L = dot(g_j, v) * ds_j
         else:
             L += dot(g_j, v) * ds_j
     return L
    def force(self, state, turbine_field):
        """ Computes the force field over turbine field

        :param state: Current solution state.
        :type state: UFL
        :param turbine_field: Turbine friction field
        :type turbine_field: UFL
        
        """
        return self.rho * turbine_field * dot(state[0], state[0]) + dot(state[1], state[1])
    def power(self, state, turbine_field):
        """ Computes the power field over the domain.

        :param state: Current solution state.
        :type state: UFL
        :param turbine_field: Turbine friction field
        :type turbine_field: UFL

        """
        return (self.rho * turbine_field * (dot(state[0], state[0]) +
                dot(state[1], state[1])) ** 1.5)
    def _speed_squared(self, state):
        """ The velocity speed with turbine cut in and out speed limits """

        speed_sq = dot(state[0], state[0]) + dot(state[1], state[1])

        if self._cut_in_speed is not None:
            speed_sq *= conditional(speed_sq < self._cut_in_speed**2, self._eps, 1)

        if self._cut_out_speed is not None:
            speed_sq = conditional(speed_sq > self._cut_out_speed**2,
                    self._cut_out_speed**2, speed_sq)

        return speed_sq
 def weak_F(t, u_t, u, v):
     # Define the differential equation.
     mesh = v.function_space().mesh()
     n = FacetNormal(mesh)
     r = Expression('x[0]', degree=1, cell=triangle)
     # All time-dependent components be set to t.
     f.t = t
     b.t = t
     kappa.t = t
     F = - inner(b, grad(u)) * v * dx \
         - 1.0 / (rho * cp) * dot(r * kappa * grad(u), grad(v / r)) * dx \
         + 1.0 / (rho * cp) * dot(r * kappa * grad(u), n) * v / r * ds \
         + 1.0 / (rho * cp) * f * v * dx
     return F
Example #7
0
 def flux_derivative(self, u, coeff):
     a = coeff
     Du = self.differential_op(u)
     Dsigma = dot(nabla_grad(a), Du)
     if element_degree(u) >= 2:
         Dsigma += a * div(Du)
     return Dsigma
Example #8
0
 def get_stiffness_form(self):
     """Get 'stiffness' / curl . curl matrix form"""
     u = self.trial_function
     v = self.test_function
     mu_r = self.material_functions['mu_r']
     s = dot(curl(v), curl(u))/mu_r*dx
     return s
Example #9
0
def test_pointsource_vector_fs(mesh, point):
    """Tests point source when given constructor PointSource(V, point,
    mag) with a vector for a vector function space that isn't placed
    at a node for 1D, 2D and 3D. Global points given to constructor
    from rank 0 processor.

    """

    rank = MPI.rank(mesh.mpi_comm())
    V = VectorFunctionSpace(mesh, "CG", 1)
    v = TestFunction(V)
    b = assemble(dot(Constant([0.0]*mesh.geometry().dim()), v)*dx)
    if rank == 0:
        ps = PointSource(V, point, 10.0)
    else:
        ps = PointSource(V, [])
    ps.apply(b)

    # Checks array sums to correct value
    b_sum = b.sum()
    assert round(b_sum - 10.0*V.num_sub_spaces()) == 0

    # Checks point source is added to correct part of the array
    v2d = vertex_to_dof_map(V)
    for v in vertices(mesh):
        if near(v.midpoint().distance(point), 0.0):
            for spc_idx in range(V.num_sub_spaces()):
                ind = v2d[v.index()*V.num_sub_spaces() + spc_idx]
                if ind < len(b.get_local()):
                    assert np.round(b.get_local()[ind] - 10.0) == 0
Example #10
0
        def __init__(self, ui, time_step_method, rho, mu, u, p0, dt, bcs, f, my_dx):
            super(TentativeVelocityProblem, self).__init__()

            W = ui.function_space()
            v = TestFunction(W)

            self.bcs = bcs

            r = SpatialCoordinate(ui.function_space().mesh())[0]

            def me(uu, ff):
                return _momentum_equation(uu, v, p0, ff, rho, mu, my_dx)

            self.F0 = rho * dot(ui - u[0], v) / dt * 2 * pi * r * my_dx
            if time_step_method == "forward euler":
                self.F0 += me(u[0], f[0])
            elif time_step_method == "backward euler":
                self.F0 += me(ui, f[1])
            else:
                assert (
                    time_step_method == "crank-nicolson"
                ), "Unknown time stepper '{}'".format(
                    time_step_method
                )
                self.F0 += 0.5 * (me(u[0], f[0]) + me(ui, f[1]))

            self.jacobian = derivative(self.F0, ui)
            self.reset_sparsity = True
            return
Example #11
0
def test_multi_ps_matrix(mesh):
    """Tests point source PointSource(V, source) for mulitple point
    sources applied to a matrix for 1D, 2D and 3D. Global points given
    to constructor from rank 0 processor.

    """

    c_ids = [0, 1, 2]
    rank = MPI.rank(mesh.mpi_comm())
    V = VectorFunctionSpace(mesh, "CG", 1, dim=2)
    u, v = TrialFunction(V), TestFunction(V)
    A = assemble(Constant(0.0)*dot(u, v)*dx)

    source = []
    if rank == 0:
        for c_id in c_ids:
            cell = Cell(mesh, c_id)
            point = cell.midpoint()
            source.append((point, 10.0))
    ps = PointSource(V, source)
    ps.apply(A)

    # Checks b sums to correct value
    a_sum = MPI.sum(mesh.mpi_comm(), np.sum(A.array()))
    assert round(a_sum - 2*len(c_ids)*10) == 0
Example #12
0
def test_pointsource_mixed_space(mesh, point):
    """Tests point source when given constructor PointSource(V, point,
    mag) with a vector for a mixed function space that isn't placed at
    a node for 1D, 2D and 3D. Global points given to constructor from
    rank 0 processor.

    """

    rank = MPI.rank(mesh.mpi_comm())
    ele1 = FiniteElement("CG", mesh.ufl_cell(), 1)
    ele2 = FiniteElement("DG", mesh.ufl_cell(), 2)
    ele3 = VectorElement("CG", mesh.ufl_cell(), 2)
    V = FunctionSpace(mesh, MixedElement([ele1, ele2, ele3]))
    value_dimension = V.element().value_dimension(0)
    v = TestFunction(V)
    b = assemble(dot(Constant([0.0]*value_dimension), v)*dx)
    if rank == 0:
        ps = PointSource(V, point, 10.0)
    else:
        ps = PointSource(V, [])
    ps.apply(b)

    # Checks array sums to correct value
    b_sum = b.sum()
    assert round(b_sum - 10.0*value_dimension) == 0
Example #13
0
def divergence_matrix(mesh):
    CR = VectorFunctionSpace(mesh, 'CR', 1)
    DG = FunctionSpace(mesh, 'DG', 0)
    A = cg1_cr_interpolation_matrix(mesh)    
    M  = assemble(dot(div(TrialFunction(CR)), TestFunction(DG))*dx())
    C = compiled_cr_module.cr_divergence_matrix(M, A, DG, CR)
    return C
Example #14
0
def les_update(nut_, nut_form, A_mass, At, u_, dt, bc_ksgs, bt, ksgs_sol,
        KineticEnergySGS, CG1, ksgs, delta, **NS_namespace):

    p, q = TrialFunction(CG1), TestFunction(CG1)

    Ck = KineticEnergySGS["Ck"]
    Ce = KineticEnergySGS["Ce"]

    Sij = sym(grad(u_))
    assemble(dt*inner(dot(u_, 0.5*grad(p)), q)*dx
             + inner((dt*Ce*sqrt(ksgs)/delta)*0.5*p, q)*dx
             + inner(dt*Ck*sqrt(ksgs)*delta*grad(0.5*p), grad(q))*dx, tensor=At)
    
    assemble(dt*2*Ck*delta*sqrt(ksgs)*inner(Sij,grad(u_))*q*dx, tensor=bt)
    bt.axpy(1.0, A_mass*ksgs.vector())
    bt.axpy(-1.0, At*ksgs.vector())
    At.axpy(1.0, A_mass, True)

    # Solve for ksgs
    bc_ksgs.apply(At, bt)
    ksgs_sol.solve(At, ksgs.vector(), bt)
    ksgs.vector().set_local(ksgs.vector().array().clip(min=1e-7))
    ksgs.vector().apply("insert")

    # Update nut_
    nut_()
    def __init__(self, V, u, v, b,
                 kappa, rho, cp,
                 source,
                 dirichlet_bcs=[],
                 neumann_bcs={},
                 robin_bcs={},
                 dx=dx,
                 ds=ds
                 ):
        super(HeatCylindrical, self).__init__()
        self.dirichlet_bcs = dirichlet_bcs
        r = Expression('x[0]', degree=1, domain=V.mesh())
        self.V = V
        self.dx_multiplier = 2*pi*r

        self.F0 = kappa * r * dot(grad(u), grad(v / (rho * cp))) \
            * 2*pi * dx
        #F -= dot(b, grad(u)) * v * 2*pi*r * dx_workpiece(0)
        if b:
            self.F0 += (b[0] * u.dx(0) + b[1] * u.dx(1)) * v * 2*pi*r * dx
        # Joule heat
        self.F0 -= 1.0 / (rho * cp) * source * v * 2*pi*r * dx
        # Neumann boundary conditions
        for k, nGradT in neumann_bcs.iteritems():
            self.F0 -= r * kappa * nGradT * v / (rho * cp) \
                * 2 * pi * ds(k)
        # Robin boundary conditions
        for k, value in robin_bcs.iteritems():
            alpha, u0 = value
            self.F0 -= r * kappa * alpha * (u - u0) * v / (rho * cp) \
                * 2 * pi * ds(k)
        return
Example #16
0
def compute_velocity_correction(
    ui, p0, p1, u_bcs, rho, mu, dt, rotational_form, my_dx, tol, verbose
):
    """Compute the velocity correction according to

    .. math::

        U = u_0 - \\frac{dt}{\\rho} \\nabla (p_1-p_0).
    """
    W = ui.function_space()
    P = p1.function_space()

    u = TrialFunction(W)
    v = TestFunction(W)
    a3 = dot(u, v) * my_dx
    phi = Function(P)
    phi.assign(p1)
    if p0:
        phi -= p0
    if rotational_form:
        r = SpatialCoordinate(W.mesh())[0]
        div_ui = 1 / r * (r * ui[0]).dx(0) + ui[1].dx(1)
        phi += mu * div_ui
    L3 = dot(ui, v) * my_dx - dt / rho * (phi.dx(0) * v[0] + phi.dx(1) * v[1]) * my_dx
    u1 = Function(W)
    solve(
        a3 == L3,
        u1,
        bcs=u_bcs,
        solver_parameters={
            "linear_solver": "iterative",
            "symmetric": True,
            "preconditioner": "hypre_amg",
            "krylov_solver": {
                "relative_tolerance": tol,
                "absolute_tolerance": 0.0,
                "maximum_iterations": 100,
                "monitor_convergence": verbose,
            },
        },
    )
    # u = project(ui - k/rho * grad(phi), V)
    # div_u = 1/r * div(r*u)
    r = SpatialCoordinate(W.mesh())[0]
    div_u1 = 1.0 / r * (r * u1[0]).dx(0) + u1[1].dx(1)
    info("||u||_div = {:e}".format(sqrt(assemble(div_u1 * div_u1 * my_dx))))
    return u1
 def weak_F(t, u_t, u, v):
     # All time-dependent components be set to t.
     u0.t = t
     f.t = f
     F = - 1.0 / (rho * cp) * kappa * dot(grad(u), grad(v)) * dx \
         + 1.0 / (rho * cp) * kappa * (u*u*u*u - u0*u0*u0*u0) * v * ds \
         + 1.0 / (rho * cp) * f * v * dx
     return F
Example #18
0
 def _get_form(self):
     n = self.function_space.cell().n
     k0 = self.k0
     E_i = self.E_i
     E_r = self.E_r
     mu_r = self._get_mur_function()
     return (1/k0/Z0)*dolfin.dot(n, (dolfin.cross(E_r, -dolfin.curl(E_i)/mu_r) +
                                     dolfin.cross(E_i, dolfin.curl(E_r)/mu_r)))*dolfin.ds
    def __init__(self, ui, theta,
                 rho, mu,
                 u, p0, dt,
                 bcs,
                 f0, f1,
                 stabilization=False,
                 dx=dx
                 ):
        super(TentativeVelocityProblem, self).__init__()

        W = ui.function_space()
        v = TestFunction(W)

        self.bcs = bcs

        r = Expression('x[0]', degree=1, domain=ui.function_space().mesh())

        #self.F0 = rho * dot(3*ui - 4*u[-1] + u[-2], v) / (2*Constant(dt)) \
        #    * 2*pi*r*dx
        #self.F0 += momentum_equation(ui, v,
        #                             p0,
        #                             f1,
        #                             rho, mu,
        #                             stabilization=stabilization,
        #                             dx=dx
        #                             )

        self.F0 = rho * dot(ui - u[-1], v) / Constant(dt) \
            * 2*pi*r*dx
        if abs(theta) > DOLFIN_EPS:
            # Implicit terms.
            if f1 is None:
                raise RuntimeError('Implicit schemes need right-hand side '
                                   'at target step (f1).')
            self.F0 += theta \
                * momentum_equation(ui, v,
                                    p0,
                                    f1,
                                    rho, mu,
                                    stabilization=stabilization,
                                    dx=dx
                                    )
        if abs(1.0 - theta) > DOLFIN_EPS:
            # Explicit terms.
            if f0 is None:
                raise RuntimeError('Explicit schemes need right-hand side '
                                   'at current step (f0).')
            self.F0 += (1.0 - theta) \
                * momentum_equation(u[-1], v,
                                    p0,
                                    f0,
                                    rho, mu,
                                    stabilization=stabilization,
                                    dx=dx
                                    )
        self.jacobian = derivative(self.F0, ui)
        self.reset_sparsity = True
        return
def _build_residuals(V, dx, phi, omega, Mu, Sigma, convections, voltages):
    #class OuterBoundary(SubDomain):
    #    def inside(self, x, on_boundary):
    #        return on_boundary and abs(x[0]) > DOLFIN_EPS
    #boundaries = FacetFunction('size_t', mesh)
    #boundaries.set_all(0)
    #outer_boundary = OuterBoundary()
    #outer_boundary.mark(boundaries, 1)
    #ds = Measure('ds')[boundaries]

    r = Expression('x[0]', degree=1, domain=V.mesh())

    subdomain_indices = Mu.keys()

    #u = TrialFunction(V)
    v = TestFunction(V)

    r_r = zero() * dx(0)
    for i in subdomain_indices:
        r_r += 1.0 / (Mu[i] * r) * dot(grad(r * phi[0]), grad(r * v)) * 2 * pi * dx(i) \
            - omega * Sigma[i] * phi[1] * v * 2 * pi * r * dx(i)
    # convections
    for i, conv in convections.items():
        r_r += dot(conv, grad(r * phi[0])) * v * 2 * pi * dx(i)
    # rhs
    for i, voltage in voltages.items():
        r_r -= Sigma[i] * voltage.real * v * dx(i)
    ## boundaries
    #r_r += 1.0/Mu[i] * phi[0] * v * 2*pi*ds(1)

    # imaginary part
    r_i = zero() * dx(0)
    for i in subdomain_indices:
        r_i += 1.0 / (Mu[i] * r) * dot(grad(r * phi[1]), grad(r * v)) * 2 * pi * dx(i) \
            + omega * Sigma[i] * phi[0] * v * 2 * pi * r * dx(i)
    # convections
    for i, conv in convections.items():
        r_i += dot(conv, grad(r * phi[1])) * v * 2 * pi * dx(i)
    # rhs
    for i, voltage in voltages.items():
        r_r -= Sigma[i] * voltage.imag * v * dx(i)
    ## boundaries
    #r_i += 1.0/Mu[i] * phi[1] * v * 2*pi*ds(1)

    return r_r, r_i
Example #21
0
def divergence_matrix(mesh):
    CR = VectorFunctionSpace(mesh, 'CR', 1)
    DG = FunctionSpace(mesh, 'DG', 0)
    A = cg1_cr_interpolation_matrix(mesh)
    M  = assemble(dot(div(TrialFunction(CR)), TestFunction(DG))*dx())
    compiled_cr_module.cr_divergence_matrix(M, A, DG, CR)
    M_mat = as_backend_type(M).mat()
    M_mat.matMult(A.mat())
    return M
Example #22
0
    def compute(self, get):
        u = get("Velocity")
        assemble(dot(u[1].dx(0)-u[0].dx(1), self.q)*dx(), tensor=self.L)
        self.bc.apply(self.L)

        self.solver.solve(self.psi.vector(), self.L)
        #solve(self.A, self.psi.vector(), self.L)

        return self.psi
Example #23
0
 def flux_derivative(self, u, coeff):
     """First derivative of flux."""
     lmbda, mu = coeff
     Du = self.differential_op(u)
     I = Identity(u.cell().d)
     Dsigma = 2.0 * mu * div(Du) + dot(nabla_grad(lmbda), tr(Du) * I)
     if element_degree(u) >= 2:
         Dsigma += lmbda * div(tr(Du) * I)
     return Dsigma
Example #24
0
def _momentum_equation(u, v, p, f, rho, mu, my_dx):
    """Weak form of the momentum equation.
    """
    # rho and my are Constant() functions
    assert rho.values()[0] > 0.0
    assert mu.values()[0] > 0.0

    # Skew-symmetric formulation.
    # Don't include the boundary term
    #
    #   - mu *inner(r*grad(u2)*n  , v2) * 2*pi*ds.
    #
    # This effectively means that at all boundaries where no sufficient
    # Dirichlet-conditions are posed, we assume grad(u)*n to vanish.
    #
    # The original term
    #    u2[0]/(r*r) * v2[0]
    # doesn't explode iff u2[0]~r and v2[0]~r at r=0. Hence, we need to enforce
    # homogeneous Dirichlet-conditions for n.u at r=0. This corresponds to no
    # flow in normal direction through the symmetry axis -- makes sense.
    # When using the 2*pi*r weighting, we can even be a bit lax on the
    # enforcement on u2[0].
    #
    # For this to be well defined, u[0]/r and u[2]/r must be bounded for r=0,
    # so u[0]~u[2]~r must hold. This either needs to be enforced in the
    # boundary conditions (homogeneous Dirichlet for u[0], u[2] at r=0) or must
    # follow from the dynamics of the system.
    #
    # TODO some more explanation for the following lines of code
    mesh = v.function_space().mesh()
    r = SpatialCoordinate(mesh)[0]
    F = (
        rho * 0.5 * (dot(grad(u) * u, v) - dot(grad(v) * u, u)) * 2 * pi * r * my_dx
        + mu * inner(r * grad(u), grad(v)) * 2 * pi * my_dx
        + mu * u[0] / r * v[0] * 2 * pi * my_dx
        - dot(f, v) * 2 * pi * r * my_dx
    )
    if p:
        F += (p.dx(0) * v[0] + p.dx(1) * v[1]) * 2 * pi * r * my_dx
    if len(u) == 3:
        F += rho * (-u[2] * u[2] * v[0] + u[0] * u[2] * v[2]) * 2 * pi * my_dx
        F += mu * u[2] / r * v[2] * 2 * pi * my_dx

    return F
Example #25
0
 def get_L_form(self):
     try:
         return self.L_form
     except AttributeError:
         pass
     # Set up equivalent magnetic current forms
     M_r = -cross(self.n, self.E_r)
     M_i = -cross(self.n, self.E_i)
     #------------------------------
     # Set up form for far field potential L
     theta_hat = self.theta_hat
     phi_hat = self.phi_hat
     phase = self.phase
     L_r = M_r*dolfin.cos(phase) - M_i*dolfin.sin(phase)
     L_i = M_r*dolfin.sin(phase) + M_i*dolfin.cos(phase)
     self.L_form = dict(
         r_theta=dot(theta_hat, L_r)*ds,
         r_phi=dot(phi_hat, L_r)*ds,
         i_theta=dot(theta_hat, L_i)*ds,
         i_phi=dot(phi_hat, L_i)*ds)
     return self.L_form
Example #26
0
    def compute(self, get):
        u = get("Velocity")
        mu = get("DynamicViscosity")
        if isinstance(mu, (float, int)):
            mu = Constant(mu)

        n = self._n
        T = -mu*dot((grad(u) + grad(u).T), n)
        Tn = dot(T, n)
        Tt = T - Tn*n

        tau_form = dot(self.v, Tt)*ds()
        assemble(tau_form, tensor=self.tau.vector())

        #self.b[self._keys] = self.tau.vector()[self._values] # FIXME: This is not safe!!!
        get_set_vector(self.b, self._keys, self.tau.vector(), self._values, self._temp_array)

        # Ensure proper scaling
        self.solver.solve(self.tau_boundary.vector(), self.b)

        return self.tau_boundary
Example #27
0
    def _get_forms(self):
        if self.dirty:
            E_r, E_i, g_r, g_i = self.E_r, self.E_i, self.g_r, self.g_i
            k0 = self.k0
            eps_r = self._get_epsr_function()
            mu_r = self._get_mur_function()
            form_r = (dot(curl(E_r)/mu_r, curl(g_r)) - dot(curl(E_i)/mu_r, curl(g_i)) \
                      - k0**2*(dot(eps_r*E_r, g_r) - dot(eps_r*E_i, g_i)))*self.dx
            form_i = (dot(curl(E_r)/mu_r, curl(g_i)) + dot(curl(E_i)/mu_r, curl(g_r)) \
                  - k0**2*(dot(eps_r*E_r, g_i) + dot(eps_r*E_i, g_r)))*self.dx
            self.form_r, self.form_i = form_r, form_i
            self.dirty = False

        return self.form_r, self.form_i
Example #28
0
    def neumann_residual(self, coeff, v, nu, mesh, homogeneous=False):
        """Neumann boundary residual."""
        form = []
        a = coeff
        boundaries = self.neumann_boundary
        g = self.g
        if boundaries is not None:
            if homogeneous:
                g = zero_function(v.function_space())

            for g_j, ds_j in self.weak_form.neumann_form_list(boundaries, g, mesh):
                r_j = g_j - a * dot(self.weak_form.flux(v, coeff), nu)
                form.append((r_j, ds_j))
        return form
Example #29
0
    def neumann_residual(self, coeff, v, nu, mesh, homogeneous=False):
        # the coefficient field does not influence the Neumann boundary for Navier-Lame!
        """Neumann boundary residual."""
        form = []
        boundaries = self.neumann_boundary
        g = self.g
        if boundaries is not None:
            if homogeneous:
                g = zero_function(v.function_space())

            for g_j, ds_j in self.weak_form.neumann_form_list(boundaries, g, mesh):
                r_j = g_j - dot(self.weak_form.flux(v, coeff), nu)
                form.append((r_j, ds_j))
        return form
def _residual_strong(dx, v, phi, mu, sigma, omega, conv, voltages):
    '''Get the residual in strong form, projected onto V.
    '''
    r = Expression('x[0]', degree=1, cell=triangle)
    R = [zero() * dx(0),
         zero() * dx(0)]
    subdomain_indices = mu.keys()
    for i in subdomain_indices:
        # diffusion, reaction
        R_r = - div(1 / (mu[i] * r) * grad(r * phi[0])) \
            - sigma[i] * omega * phi[1]
        R_i = - div(1 / (mu[i] * r) * grad(r * phi[1])) \
            + sigma[i] * omega * phi[0]
        # convection
        if i in conv:
            R_r += dot(conv[i], 1 / r * grad(r * phi[0]))
            R_i += dot(conv[i], 1 / r * grad(r * phi[1]))
        # right-hand side
        if i in voltages:
            R_r -= sigma[i] * voltages[i].real / (2 * pi * r)
            R_i -= sigma[i] * voltages[i].imag / (2 * pi * r)
        R[0] += R_r * v * dx(i)
        R[1] += R_i * v * dx(i)
    return R
Example #31
0
def run_and_calculate_error(N, dt, tmax, polydeg_rho, last=False):
    """
    Run Ocellaris and return L2 & H1 errors in the last time step
    """
    say(N, dt, tmax, polydeg_rho)

    # Setup and run simulation
    sim = Simulation()
    sim.input.read_yaml('transport.inp')

    mesh_type = sim.input.get_value('mesh/type')
    if mesh_type == 'XML':
        # Create unstructured mesh with gmsh
        cmd1 = [
            'gmsh', '-string',
            'lc = %f;' % (3.14 / N), '-o',
            'disc_%d.msh' % N, '-2',
            '../convergence-variable-density-disk/disc.geo'
        ]
        cmd2 = ['dolfin-convert', 'disc_%d.msh' % N, 'disc.xml']
        with open('/dev/null', 'w') as devnull:
            for cmd in (cmd1, cmd2):
                say(' '.join(cmd))
                if ISROOT:
                    subprocess.call(cmd, stdout=devnull, stderr=devnull)
    elif mesh_type == 'UnitDisc':
        sim.input.set_value('mesh/N', N // 2)
    else:
        sim.input.set_value('mesh/Nx', N)
        sim.input.set_value('mesh/Ny', N)

    sim.input.set_value('time/dt', dt)
    sim.input.set_value('time/tmax', tmax)
    sim.input.set_value('multiphase_solver/polynomial_degree_rho', polydeg_rho)
    sim.input.set_value('output/stdout_enabled', False)

    say('Running with multiphase solver %s ...' %
        (sim.input.get_value('multiphase_solver/type')))
    t1 = time.time()
    setup_simulation(sim)
    run_simulation(sim)
    duration = time.time() - t1
    say('DONE')

    # Interpolate the analytical solution to the same function space
    Vu = sim.data['Vu']
    Vp = sim.data['Vp']
    Vr = sim.data['Vrho']
    polydeg_r = Vr.ufl_element().degree()
    vals = dict(t=sim.time, dt=sim.dt)
    rho_e = dolfin.Expression(
        sim.input.get_value('initial_conditions/rho_p/cpp_code'),
        degree=polydeg_r,
        **vals)
    rho_a = dolfin.project(rho_e, Vr)

    rho_e.t = 0
    rho_0 = dolfin.project(rho_e, Vr)

    # Calculate L2 errors
    err_rho = calc_err(sim.data['rho'], rho_a)

    # Calculate H1 errors
    err_rho_H1 = calc_err(sim.data['rho'], rho_a, 'H1')

    mesh = sim.data['mesh']
    n = dolfin.FacetNormal(mesh)

    reports = sim.reporting.timestep_xy_reports
    say('Num time steps:', sim.timestep)
    say('Num cells:', mesh.num_cells())
    say('Co_max:', numpy.max(reports['Co']))
    say('rho_min went from %r to %r' %
        (reports['min(rho)'][0], reports['min(rho)'][-1]))
    say('rho_max went from %r to %r' %
        (reports['max(rho)'][0], reports['max(rho)'][-1]))
    m0, m1 = reports['mass'][0], reports['mass'][-1]
    say('mass error %.3e (%.3e)' % (m1 - m0, (m1 - m0) / m0))
    say('vel compat error %.3e' %
        dolfin.assemble(dolfin.dot(sim.data['u'], n) * dolfin.ds))
    int_p = dolfin.assemble(sim.data['p'] * dolfin.dx)
    say('p*dx', int_p)
    div_u_Vp = abs(
        dolfin.project(dolfin.div(sim.data['u']),
                       Vp).vector().get_local()).max()
    say('div(u)|Vp', div_u_Vp)
    div_u_Vu = abs(
        dolfin.project(dolfin.div(sim.data['u']),
                       Vu).vector().get_local()).max()
    say('div(u)|Vu', div_u_Vu)
    Vdg0 = dolfin.FunctionSpace(mesh, "DG", 0)
    div_u_DG0 = abs(
        dolfin.project(dolfin.div(sim.data['u']),
                       Vdg0).vector().get_local()).max()
    say('div(u)|DG0', div_u_DG0)
    Vdg1 = dolfin.FunctionSpace(mesh, "DG", 1)
    div_u_DG1 = abs(
        dolfin.project(dolfin.div(sim.data['u']),
                       Vdg1).vector().get_local()).max()
    say('div(u)|DG1', div_u_DG1)

    isoparam = mesh.ufl_coordinate_element().degree() > 1
    if last and (not isoparam
                 or sim.input.get_value('mesh/type') == 'UnitDisc'):
        # Plot the results
        for fa, name in ((rho_a, 'rho'), ):
            fh = sim.data[name]
            if isoparam:
                # Bug in matplotlib plotting for isoparametric elements
                mesh2 = dolfin.UnitDiscMesh(dolfin.MPI.comm_world, N // 2, 1,
                                            2)
                ue = fa.function_space().ufl_element()
                V2 = dolfin.FunctionSpace(mesh2, ue.family(), ue.degree())
                fa2, fh2 = dolfin.Function(V2), dolfin.Function(V2)
                fa2.vector().set_local(fa.vector().get_local())
                fh2.vector().set_local(fh.vector().get_local())
                fa, fh = fa2, fh2
            plot(fh - fa, name + ' diff', '%g_%g_%s_diff' % (N, dt, name))
            plot(fa, name + ' analytical',
                 '%g_%g_%s_analytical' % (N, dt, name))
            plot(fh, name + ' numerical', '%g_%g_%s_numerical' % (N, dt, name))
            plot(rho_0, name + ' initial', '%g_%g_%s_initial' % (N, dt, name))

    hmin = mesh.hmin()
    return err_rho, err_rho_H1, hmin, dt, duration
Example #32
0
displacements_function = df.Function(displacements_function_space)
v = df.TestFunction(displacements_function_space)
residual_form = get_residual_form(displacements_function, v, density_function,
                                  density_function_space, tractionBC, f, 1)

pde_problem.add_state('displacements', displacements_function, residual_form,
                      'density')

# Add output-avg_density to the PDE problem:
volume = df.assemble(df.Constant(1.) * df.dx(domain=mesh))
avg_density_form = density_function / (df.Constant(
    1. * volume)) * df.dx(domain=mesh)
pde_problem.add_scalar_output('avg_density', avg_density_form, 'density')

# Add output-compliance to the PDE problem:
compliance_form = df.dot(f, displacements_function) * dss(6)
pde_problem.add_scalar_output('compliance', compliance_form, 'displacements')

# Add boundary conditions to the PDE problem:
pde_problem.add_bc(
    df.DirichletBC(displacements_function_space, df.Constant((0.0, 0.0)),
                   '(abs(x[0]-0.) < DOLFIN_EPS)'))

# Define the OpenMDAO problem and model
prob = om.Problem()

num_dof_density = pde_problem.inputs_dict['density'][
    'function'].function_space().dim()

comp = om.IndepVarComp()
comp.add_output(
Example #33
0
def test_moving_mesh():
    t = 0.
    dt = 0.025
    num_steps = 20
    xmin, ymin = 0., 0.
    xmax, ymax = 2., 2.
    xc, yc = 1., 1.
    nx, ny = 20, 20
    pres = 150
    k = 1

    mesh = RectangleMesh(Point(xmin, ymin), Point(xmax, ymax), nx, ny)
    n = FacetNormal(mesh)

    # Class for mesh motion
    dU = PeriodicVelocity(xmin, xmax, dt, t, degree=1)

    Qcg = VectorFunctionSpace(mesh, 'CG', 1)

    boundaries = MeshFunction("size_t", mesh, mesh.topology().dim()-1)
    boundaries.set_all(0)
    leftbound = Left(xmin)

    leftbound.mark(boundaries, 99)
    ds = Measure('ds', domain=mesh, subdomain_data=boundaries)

    # Create function spaces
    Q_E_Rho = FiniteElement("DG", mesh.ufl_cell(), k)
    T_1 = FunctionSpace(mesh, 'DG', 0)
    Qbar_E = FiniteElement("DGT", mesh.ufl_cell(), k)

    Q_Rho = FunctionSpace(mesh, Q_E_Rho)
    Qbar = FunctionSpace(mesh, Qbar_E)

    phih, phih0 = Function(Q_Rho), Function(Q_Rho)
    phibar = Function(Qbar)

    # Advective velocity
    uh = Function(Qcg)
    uh.assign(Constant((0., 0.)))
    # Mesh velocity
    umesh = Function(Qcg)
    # Total velocity
    uadvect = uh-umesh

    # Now throw in the particles
    x = RandomRectangle(Point(xmin, ymin), Point(xmax, ymax)).generate([pres, pres])
    s = assign_particle_values(x, GaussianPulse(center=(xc, yc), sigma=float(0.25),
                                                U=[0, 0], time=0., height=1., degree=3))
    x = comm.bcast(x, root=0)
    s = comm.bcast(s, root=0)
    p = particles(x, [s], mesh)

    # Define projections problem
    FuncSpace_adv = {'FuncSpace_local': Q_Rho, 'FuncSpace_lambda': T_1, 'FuncSpace_bar': Qbar}
    FormsPDE = FormsPDEMap(mesh, FuncSpace_adv, ds=ds)
    forms_pde = FormsPDE.forms_theta_linear(phih0, uadvect, dt, Constant(1.0), zeta=Constant(0.))
    pde_projection = PDEStaticCondensation(mesh, p,
                                           forms_pde['N_a'], forms_pde['G_a'], forms_pde['L_a'],
                                           forms_pde['H_a'],
                                           forms_pde['B_a'],
                                           forms_pde['Q_a'], forms_pde['R_a'], forms_pde['S_a'],
                                           [], 1)

    # Initialize the initial condition at mesh by an l2 projection
    lstsq_rho = l2projection(p, Q_Rho, 1)
    lstsq_rho.project(phih0.cpp_object())

    for step in range(num_steps):
        # Compute old area at old configuration
        old_area = assemble(phih0*dx)

        # Pre-assemble rhs
        pde_projection.assemble_state_rhs()

        # Move mesh
        dU.compute_ubc()
        umesh.assign(project(dU, Qcg))

        ALE.move(mesh, project(dU * dt, Qcg))
        dU.update()

        # Relocate particles as a result of mesh motion
        # NOTE: if particles were advected themselve,
        # we had to run update_facets_info() here as well
        p.relocate()

        # Assemble left-hand side on new config, but not the right-hand side
        pde_projection.assemble(True, False)
        pde_projection.solve_problem(phibar.cpp_object(), phih.cpp_object(),
                                     'mumps', 'none')

        # Needed to compute conservation, note that there
        # is an outgoing flux at left boundary
        new_area = assemble(phih*dx)
        gamma = conditional(ge(dot(uadvect, n), 0), 0, 1)
        bflux = assemble((1-gamma) * dot(uadvect, n) * phih * ds)

        # Update solution
        assign(phih0, phih)

        # Put assertion on (global) mass balance, local mass balance is
        # too time consuming but should pass also
        assert new_area - old_area + bflux * dt < 1e-12

        # Assert that max value of phih stays close to 2 and
        # min value close to 0. This typically will fail if
        # we do not do a correct relocate of particles
        assert np.amin(phih.vector().get_local()) > -0.015
        assert np.amax(phih.vector().get_local()) < 1.04
Example #34
0
    def __init__(self, centers, J, n):
        self.centers = centers
        self.J = J

        self.target = 0.002
        self.J /= self.target

        # dir_path = os.path.dirname(os.path.realpath(__file__))
        # with open(os.path.join(dir_path, '../colorio/data/gamut_triangulation.yaml')) as f:
        #     data = yaml.safe_load(f)

        # self.points = np.column_stack([
        #     data['points'], np.zeros(len(data['points']))
        #     ])
        # self.cells = np.array(data['cells'])

        # self.points, self.cells = colorio.xy_gamut_mesh(0.15)

        self.points, self.cells = meshzoo.triangle(
            n, corners=np.array([[0.0, 0.0], [1.0, 0.0], [0.0, 1.0]])
        )

        # https://bitbucket.org/fenics-project/dolfin/issues/845/initialize-mesh-from-vertices
        editor = MeshEditor()
        mesh = Mesh()
        editor.open(mesh, "triangle", 2, 2)
        editor.init_vertices(self.points.shape[0])
        editor.init_cells(self.cells.shape[0])
        for k, point in enumerate(self.points):
            editor.add_vertex(k, point)
        for k, cell in enumerate(self.cells):
            editor.add_cell(k, cell)
        editor.close()

        self.V = FunctionSpace(mesh, "CG", 1)
        self.Vgrad = VectorFunctionSpace(mesh, "DG", 0)

        # self.ux0 = Function(self.V)
        # self.uy0 = Function(self.V)

        # 0 starting guess
        # ax = np.zeros(self.V.dim())
        # ay = np.zeros(self.V.dim())

        # Use F(x, y) = (x, y) as starting guess
        self.ux0 = project(Expression("x[0]", degree=1), self.V)
        self.uy0 = project(Expression("x[1]", degree=1), self.V)
        ax = self.ux0.vector().get_local()
        ay = self.uy0.vector().get_local()
        # Note that alpha doesn't contain the values in the order that one might expect,
        # see
        # <https://www.allanswered.com/post/awevg/projectexpressionx0-v-vector-get_local-not-in-order/>.
        self.alpha = np.concatenate([ax, ay])

        self.num_f_eval = 0

        # Build L as scipy.csr_matrix
        u = TrialFunction(self.V)
        v = TestFunction(self.V)
        L = assemble(dot(grad(u), grad(v)) * dx)
        Lmat = as_backend_type(L).mat()
        indptr, indices, data = Lmat.getValuesCSR()

        size = Lmat.getSize()
        self.L = sparse.csr_matrix((data, indices, indptr), shape=size)
        self.LT = self.L.getH()

        self.dx, self.dy = build_grad_matrices(self.V, centers)
        self.dxT = self.dx.getH()
        self.dyT = self.dy.getH()
        return
Example #35
0
tol = 1E-14


def boundary_D(x, on_boundary):

    return on_boundary and (near(x[0], 0, tol) or near(x[0], 1.0, tol))


bc = DirichletBC(V, u_D, boundary_D)
u = TrialFunction(V)
v = TestFunction(V)
f = Expression("10 * exp( - (pow(x[0] - 0.5, 2) + pow(x[1] - 0.5, 2) \
                 + pow(x[2] - 0.5, 2)) / 1)",
               degree=6)
g = Expression("sin(5.0*x[0])*sin(5.0*x[1])", degree=6)
a = dot(grad(u), grad(v)) * dx
L = f * v * dx + g * v * ds
A = PETScMatrix()
b = PETScVector()
assemble_system(a, L, bc, A_tensor=A, b_tensor=b)

A = A.mat()
b = b.vec()

# =========================================================================

# Construct the alist for systems on levels from fine to coarse
# construct the transfer operators first
ruse = [None] * (nl - 1)
Alist = [None] * (nl)
def Cost(xp):
    global x_old, rho_old
    comm = nMPI.COMM_WORLD
    mpi_rank = comm.Get_rank()

    x1, x2 = xp

    rs = 8.0  # radiation boundary radius
    l = x1  # Patch length
    w = 4.5  # Patch width
    s1 = x2 * x1 / 2.0  # Feed offset
    h = 1.0   # Patch height
    t = 0.05   # Metal thickness
    lc = 1.0  # Coax length
    rc = 0.25 # Coax shield radius
    cc = 0.107 #Coax center conductor 50 ohm air diel
    eps = 1.0e-4
    tol = 1.0e-6
    eta = 377.0
    eps_c = 1.0

    k0 = 2.45 * 2.0 * np.pi / 30.0 # Frequency in GHz
    ls = 0.025
    lm = 0.8
    lw = 0.06
    lp = 0.3

    if mpi_rank == 0:
        print("x[0] = {0:<f}, x[1] = {1:<f} ".format(xp[0], xp[1]))
        print("length = {0:<f}, width = {1:<f}, feed offset = {2:<f}".format(l, w, s1))
        gmsh.initialize()
        gmsh.option.setNumber('General.Terminal', 1)
        gmsh.model.add("SimplePatchOpt")
# Radiation sphere
        gmsh.model.occ.addSphere(0.0, 0.0, 0.0, rs, 1)
        gmsh.model.occ.addBox(0.0, -rs, 0.0, rs, 2*rs, rs, 2)
        gmsh.model.occ.intersect([(3,1)],[(3,2)], 3, removeObject=True, removeTool=True)
# Patch
        gmsh.model.occ.addBox(0.0, -l/2, h, w/2, l, t, 4)
# coax center
        gmsh.model.occ.addCylinder(0.0, s1, -lc, 0.0, 0.0, lc+h, cc, 5, 2.0*np.pi)
# patch center gnd via
        #gmsh.model.occ.addCylinder(0.0, 0.0, 0.0, 0.0, 0.0, h, cc, 6, 2.0*np.pi)

# coax shield
        gmsh.model.occ.addCylinder(0.0, s1, -lc, 0.0, 0.0, lc, rc, 7)
        gmsh.model.occ.addBox(0.0, s1-rc, -lc, rc, 2.0*rc, lc, 8)
        gmsh.model.occ.intersect([(3,7)], [(3,8)], 9, removeObject=True, removeTool=True)
        gmsh.model.occ.fuse([(3,3)], [(3,9)], 10, removeObject=True, removeTool=True)
# cutout internal boundaries
        #gmsh.model.occ.cut([(3,10)], [(3,4),(3,5),(3,6)], 11, removeObject=True, removeTool=True)
        gmsh.model.occ.cut([(3,10)], [(3,4),(3,5)], 11, removeObject=True, removeTool=True)

        gmsh.option.setNumber('Mesh.MeshSizeMin', ls)
        gmsh.option.setNumber('Mesh.MeshSizeMax', lm)
        gmsh.option.setNumber('Mesh.Algorithm', 6)
        gmsh.option.setNumber('Mesh.Algorithm3D', 1)
#        gmsh.option.setNumber('Mesh.MshFileVersion', 2.2)
        gmsh.option.setNumber('Mesh.MshFileVersion', 4.1)
        gmsh.option.setNumber('Mesh.Format', 1)
        gmsh.option.setNumber('Mesh.MinimumCirclePoints', 36)
        gmsh.option.setNumber('Mesh.CharacteristicLengthFromCurvature', 1)

        gmsh.model.occ.synchronize()

        pts = gmsh.model.getEntities(0)
        gmsh.model.mesh.setSize(pts, lm) #Set background mesh density
        pts = gmsh.model.getEntitiesInBoundingBox(-eps, -l/2-eps, h-eps, w/2+eps, l/2+eps, h+t+eps)
        gmsh.model.mesh.setSize(pts, ls)

        pts = gmsh.model.getEntitiesInBoundingBox(-eps, s1-rc-eps, -lc-eps, rc+eps, s1+rc+eps, h+eps)
        gmsh.model.mesh.setSize(pts, lw)
        pts = gmsh.model.getEntitiesInBoundingBox(-eps, -rc-eps, -eps, rc+eps, rc+eps, eps)
        gmsh.model.mesh.setSize(pts, lw)

# Embed points to reduce mesh density on patch faces
        fce1 = gmsh.model.getEntitiesInBoundingBox(-eps, -l/2-eps, h+t-eps, w/2+eps, l/2+eps, h+t+eps, 2)
        gmsh.model.occ.synchronize()
        gmsh.model.geo.addPoint(w/4, -l/4, h+t, lp, 1000)
        gmsh.model.geo.addPoint(w/4, 0.0, h+t, lp, 1001)
        gmsh.model.geo.addPoint(w/4, l/4, h+t, lp, 1002)
        gmsh.model.geo.synchronize()
#        sf1 = gmsh.model.occ.fragment(fce1, [(0,1000),(0,1001), (0,1002)], -1, True, True)
        gmsh.model.occ.synchronize()
        print(fce1)
        fce2 = gmsh.model.getEntitiesInBoundingBox(-eps, -l/2-eps, h-eps, w/2+eps, l/2+eps, h+eps, 2)
        gmsh.model.geo.addPoint(w/4, -9*l/32, h, lp, 1003)
        gmsh.model.geo.addPoint(w/4, 0.0, h, lp, 1004)
        gmsh.model.geo.addPoint(w/4, 9*l/32, h, lp, 1005)
        gmsh.model.geo.synchronize()
        for tt in fce1:
           gmsh.model.mesh.embed(0, [1000, 1001, 1002], 2, tt[1])
        for tt in fce2:
           gmsh.model.mesh.embed(0, [1003, 1004, 1005], 2, tt[1])
#        sf2 = gmsh.model.occ.fragment(fce2, [(0,1003),(0,1004), (0,1005)], -1, True, True)
        print(fce2)
        gmsh.model.occ.remove(fce1)
        gmsh.model.occ.remove(fce2)
        gmsh.model.occ.synchronize()
        gmsh.model.addPhysicalGroup(3, [11], 1)
        gmsh.model.setPhysicalName(3, 1, "Air")
        gmsh.model.mesh.optimize("Relocate3D", niter=5)
        gmsh.model.mesh.generate(3)
        gmsh.write("SimplePatch.msh")
#        gmsh.fltk.run()
        gmsh.finalize()
        msh = meshio.read("SimplePatch.msh")
        for cell in msh.cells:
            if  cell.type == "tetra":
                tetra_cells = cell.data

        for key in msh.cell_data_dict["gmsh:physical"].keys():
            if key == "tetra":
                tetra_data = msh.cell_data_dict["gmsh:physical"][key]

        tetra_mesh = meshio.Mesh(points=msh.points, cells={"tetra": tetra_cells},
                           cell_data={"VolumeRegions":[tetra_data]})

        meshio.write("mesh.xdmf", tetra_mesh)

    mesh = dolfin.Mesh()
    with dolfin.XDMFFile("mesh.xdmf") as infile:
        infile.read(mesh)
    mvc = dolfin.MeshValueCollection("size_t", mesh, 3)
    with dolfin.XDMFFile("mesh.xdmf") as infile:
        infile.read(mvc, "VolumeRegions")
    cf = dolfin.cpp.mesh.MeshFunctionSizet(mesh, mvc)

    class PEC(dolfin.SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary

    class InputBC(dolfin.SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and dolfin.near(x[2], -lc, tol)

    class OutputBC(dolfin.SubDomain):
        def inside(self, x, on_boundary):
            rr = np.sqrt(x[0]*x[0]+x[1]*x[1]+x[2]*x[2])
            return on_boundary and dolfin.near(rr, 8.0, 1.0e-1)

    class PMC(dolfin.SubDomain):
        def inside(self, x, on_boundary):
            return on_boundary and dolfin.near(x[0], 0.0, tol)


# Volume domains
    dolfin.File("VolSubDomains.pvd").write(cf)
    dolfin.File("Mesh.pvd").write(mesh)
# Mark boundaries
    sub_domains = dolfin.MeshFunction("size_t", mesh, mesh.topology().dim() - 1)
    sub_domains.set_all(4)
    pec = PEC()
    pec.mark(sub_domains, 0)
    in_port = InputBC()
    in_port.mark(sub_domains, 1)
    out_port = OutputBC()
    out_port.mark(sub_domains, 2)
    pmc = PMC()
    pmc.mark(sub_domains, 3)
    dolfin.File("BoxSubDomains.pvd").write(sub_domains)
# Set up function spaces
    cell = dolfin.tetrahedron
    ele_type = dolfin.FiniteElement('N1curl', cell, 2, variant="integral") # H(curl) element for EM
    V2 = dolfin.FunctionSpace(mesh, ele_type * ele_type)
    V = dolfin.FunctionSpace(mesh, ele_type)
    (u_r, u_i) = dolfin.TrialFunctions(V2)
    (v_r, v_i) = dolfin.TestFunctions(V2)
    dolfin.info(mesh)
#surface integral definitions from boundaries
    ds = dolfin.Measure('ds', domain = mesh, subdomain_data = sub_domains)
#volume regions
    dx_air = dolfin.Measure('dx', domain = mesh, subdomain_data = cf, subdomain_id = 1)
    dx_subst = dolfin.Measure('dx', domain = mesh, subdomain_data = cf, subdomain_id = 2)
# with source and sink terms
    u0 = dolfin.Constant((0.0, 0.0, 0.0)) #PEC definition

    h_src = dolfin.Expression(('-(x[1] - s) / (2.0 * pi * (pow(x[0], 2.0) + pow(x[1] - s,2.0)))', 'x[0] / (2.0 * pi *(pow(x[0],2.0) + pow(x[1] - s,2.0)))', 0.0), degree = 2,  s = s1)
    e_src = dolfin.Expression(('x[0] / (2.0 * pi * (pow(x[0], 2.0) + pow(x[1] - s,2.0)))', 'x[1] / (2.0 * pi *(pow(x[0],2.0) + pow(x[1] - s,2.0)))', 0.0), degree = 2, s = s1)
    Rrad = dolfin.Expression(('sqrt(x[0] * x[0] + x[1] * x[1] + x[2] * x[2])'), degree = 2)
#Boundary condition dictionary
    boundary_conditions = {0: {'PEC' : u0},
                       1: {'InputBC': (h_src)},
                       2: {'OutputBC': Rrad}}

    n = dolfin.FacetNormal(mesh)

#Build PEC boundary conditions for real and imaginary parts
    bcs = []
    for i in boundary_conditions:
        if 'PEC' in boundary_conditions[i]:
            bc = dolfin.DirichletBC(V2.sub(0), boundary_conditions[i]['PEC'], sub_domains, i)
            bcs.append(bc)
            bc = dolfin.DirichletBC(V2.sub(1), boundary_conditions[i]['PEC'], sub_domains, i)
            bcs.append(bc)

# Build input BC source term and loading term
    integral_source = []
    integrals_load =[]
    for i in boundary_conditions:
        if 'InputBC' in boundary_conditions[i]:
            r = boundary_conditions[i]['InputBC']
            bb1 = 2.0 * (k0 * eta) * dolfin.inner(v_i, dolfin.cross(n, r)) * ds(i) #Factor of two from field equivalence principle
            integral_source.append(bb1)
            bb2 = dolfin.inner(dolfin.cross(n, v_i), dolfin.cross(n, u_r)) * k0 * np.sqrt(eps_c) * ds(i)
            integrals_load.append(bb2)
            bb2 = dolfin.inner(-dolfin.cross(n, v_r), dolfin.cross(n, u_i)) * k0 * np.sqrt(eps_c) * ds(i)
            integrals_load.append(bb2)

    for i in boundary_conditions:
        if 'OutputBC' in boundary_conditions[i]:
           r = boundary_conditions[i]['OutputBC']
           bb2 = (dolfin.inner(dolfin.cross(n, v_i), dolfin.cross(n, u_r)) * k0 + 1.0 * dolfin.inner(dolfin.cross(n, v_i), dolfin.cross(n, u_i)) / r)* ds(i)
           integrals_load.append(bb2)
           bb2 = (dolfin.inner(-dolfin.cross(n, v_r), dolfin.cross(n, u_i)) * k0 + 1.0 * dolfin.inner(dolfin.cross(n, v_r), dolfin.cross(n, u_r)) / r)* ds(i)
           integrals_load.append(bb2)
# for PMC, do nothing. Natural BC.

    a = (dolfin.inner(dolfin.curl(v_r), dolfin.curl(u_r)) + dolfin.inner(dolfin.curl(v_i), dolfin.curl(u_i)) - eps_c * k0 * k0 * (dolfin.inner(v_r, u_r) + dolfin.inner(v_i, u_i))) * dx_subst + (dolfin.inner(dolfin.curl(v_r), dolfin.curl(u_r)) + dolfin.inner(dolfin.curl(v_i), dolfin.curl(u_i)) - k0 * k0 * (dolfin.inner(v_r, u_r) + dolfin.inner(v_i, u_i))) * dx_air + sum(integrals_load)
    L = sum(integral_source)

    u1 = dolfin.Function(V2)
    vdim = u1.vector().size()
    print("Solution vector size =", vdim)

    dolfin.solve(a == L, u1, bcs, solver_parameters = {'linear_solver' : 'mumps'}) 


    u1_r, u1_i = u1.split(True)
    fp = dolfin.File("EField_r.pvd")
    fp << u1_r
    fp = dolfin.File("EField_i.pvd")
    fp << u1_i

#fp = File('WaveFile.pvd')

#ut = u1_r.copy(deepcopy=True)
#for i in range(50):
#    ut.vector().zero()
#    ut.vector().axpy(cos(pi * i / 25.0 + pi / 2.0), u1_i.vector())
#    ut.vector().axpy(cos(pi * i / 25.0), u1_r.vector()) 
#    fp << (ut, i)
    H = dolfin.interpolate(h_src, V) # Get input field
    P =  dolfin.assemble((-dolfin.dot(u1_r,dolfin.cross(dolfin.curl(u1_i),n))+dolfin.dot(u1_i,dolfin.cross(dolfin.curl(u1_r),n))) * ds(2))
    P_refl = dolfin.assemble((-dolfin.dot(u1_i,dolfin.cross(dolfin.curl(u1_r), n)) + dolfin.dot(u1_r, dolfin.cross(dolfin.curl(u1_i), n))) * ds(1))
    P_inc = dolfin.assemble((dolfin.dot(H, H) * eta / (2.0 * np.sqrt(eps_c))) * ds(1))
    print("Integrated power on port 2:", P/(2.0 * k0 * eta))
    print("Incident power at port 1:", P_inc)
    print("Integrated reflected power on port 1:", P_inc - P_refl / (2.0 * k0 * eta))
    rho_old = (P_inc - P_refl / (2.0 * k0 * eta)) / P_inc #Fraction of incident power reflected as objective function
    return rho_old
 def j(self, t, u):
     return Problem_Basic.j(self, t, dol.assemble(dol.dot(u,self.v)*dol.dx).get_local())
def k_plus(k, n):
    return dot(dot(n('+'), k('+')), n('+'))
Example #39
0
cell = mesh.ufl_cell()
displacement_fe = df.VectorElement("CG", cell, 1)
temperature_fe = df.FiniteElement("CG", cell, 1)

mixed_fs = df.FunctionSpace(mesh,
                            df.MixedElement([displacement_fe, temperature_fe]))
mixed_fs.sub(1).dofmap().dofs()
mixed_function = df.Function(mixed_fs)
displacements_function, temperature_function = df.split(mixed_function)

v, T_hat = df.TestFunctions(mixed_fs)

residual_form = get_residual_form(displacements_function, v, density_function,
                                  temperature_function, T_hat, KAPPA, K, ALPHA)

residual_form -=  (df.dot(f_r, v) * dss(10) + df.dot(f_t, v) * dss(14)  + \
                    q*T_hat*dss(5) + q_half*T_hat*dss(6) + q_quart*T_hat*dss(7))
print("get residual_form-------")
pde_problem.add_state('mixed_states', mixed_function, residual_form, 'density')
'''
4. 3. Add outputs
'''

# Add output-avg_density to the PDE problem:
volume = df.assemble(df.Constant(1.) * df.dx(domain=mesh))
avg_density_form = density_function / (df.Constant(
    1. * volume)) * df.dx(domain=mesh)
pde_problem.add_scalar_output('avg_density', avg_density_form, 'density')
print("Add output-avg_density-------")

# Add output-compliance to the PDE problem:
Example #40
0
def ns_IPCS_convection_supg(VQL, mesh, bcs, dt, parameter):
    mu, rho, nu, D = parameter
    V, Q, L = VQL
    vu, vp, vr = TestFunction(V), TestFunction(Q), TestFunction(
        L)  # for integration
    u_, p_, r_ = Function(V), Function(Q), Function(L)  # for the solution
    u_1, p_1, r_1 = Function(V), Function(Q), Function(
        L)  # for the prev. solution
    u, p, r = TrialFunction(V), TrialFunction(Q), TrialFunction(L)  # unknown!
    tau_SUPG = Function(L)

    bcu = [bcs[0], bcs[1]]  # note: no-slip at cylinder wall is no longer used!
    bcp = [bcs[2]]
    bcr = [DirichletBC(L, rho, inlet)]

    # print(h)
    # print(h.min(), h.max(), h.mean())

    # # C++ version (does not work)
    # ue_code = '''
    # //https://fenicsproject.discourse.group/t/pass-function-to-c-expression/1081

    # #include <pybind11/pybind11.h>
    # #include <pybind11/eigen.h>
    # #include <dolfin/mesh/Vertex.h>
    # namespace py = pybind11;
    # #include <dolfin/function/Expression.h>
    # #include <dolfin/function/Function.h>
    # #include <dolfin/mesh/Mesh.h>

    # class SUPG : public dolfin::Expression
    # {
    # public:
    #     double D;
    #     // std::shared_ptr<Mesh> mesh; // doesn work

    #     std::shared_ptr<dolfin::Function> velocity;
    #     SUPG(std::shared_ptr<dolfin::Function> u_) : dolfin::Expression(2)
    #     {
    #         velocity = u_;
    #     }

    #     void eval(Eigen::Ref<Eigen::VectorXd> values,
    #               Eigen::Ref<const Eigen::VectorXd> x,
    #               const ufc::cell& cell) const override
    #     {
    #         //Cell cell(*mesh, c.index);
    #         velocity->eval(values, x);  // values now holds the velocity?
    #         double tau = 0.0;
    #         //double h = cell.h();
    #         //double h = cell.diameter();

    #         double h = 0.015;
    #         double magnitude = 0.0;  // pythagoras
    #         for (uint i=0; i<x.size(); ++i)
    #         {
    #             magnitude += values[i] * values[i];
    #         }
    #         magnitude = sqrt(magnitude);
    #         double Pe = magnitude * h / (2.0 * D);
    #         if (Pe > DOLFIN_EPS)
    #         {
    #             tau = h / (2.0*magnitude) * (1.0/tanh(Pe) - 1.0/Pe);
    #         }
    #         values[0] = tau;
    #     };
    # };

    # PYBIND11_MODULE(SIGNATURE, m)
    # {
    #   py::class_<SUPG, std::shared_ptr<SUPG>, dolfin::Expression>
    #     (m, "SUPG")
    #     .def(py::init<std::shared_ptr<dolfin::Function>>())
    #     .def_readwrite("D", &SUPG::D)
    #     .def_readwrite("velocity", &SUPG::velocity);
    # }
    # '''
    # compiled = compile_cpp_code(ue_code)
    # expr = CompiledExpression(compiled.SUPG(u_.cpp_object()), D=D, degree=1)
    # tau_supg_from_expr = project(expr, mesh=mesh).vector().vec().array
    # print(tau_supg_from_expr)

    # class _rho_(UserExpression):
    #     def eval(self, values, x):
    #         if (x[0]-.2)*(x[0]-.2) + (x[1]-.2)*(x[1]-.2) < 0.0025:
    #             values[0] = rho*5
    #         else:
    #             values[0] = rho
    # f0 = _rho_(degree=2, element=L.ufl_element())
    # r_1.assign(project(f0, mesh=mesh))

    x, y = np.split(L.tabulate_dof_coordinates(), 2, 1)
    x, y = x.ravel(), y.ravel()
    ll = (x - .2) * (x - .2) + (y - .2) * (y - .2) < 0.0025  # logic list
    r_1.vector().vec().array = rho
    r_1.vector().vec().array[ll] = rho * 5

    # cells_mapped = np.empty((mesh.num_cells(), 3), dtype=np.int32)
    # for i in range(mesh.num_cells()):  # len(mesh.cells())
    #     # print(cells_mapped[i], L.dofmap().cell_dofs(i))
    #     cells_mapped[i] = L.dofmap().cell_dofs(i)

    # data_mapped = r_1.vector().vec().array
    # fig, ax = plt.subplots()
    # ax.tricontourf(x, y, cells_mapped, data_mapped, levels=15)
    # ax.set_aspect("equal")
    # plt.suptitle("initial density")
    # plt.show()

    n = FacetNormal(mesh)
    u_mid = (u + u_1) / 2.0
    F1 = r_1*dot((u - u_1) / dt, vu)*dx \
        + r_1*dot(dot(u_1, nabla_grad(u_1)), vu)*dx \
        + inner(sigma(u_mid, p_1, mu), epsilon(vu))*dx \
        + dot(p_1*n, vu)*ds - dot(mu*nabla_grad(u_mid)*n, vu)*ds
    a1 = lhs(F1)
    L1 = rhs(F1)
    # Define variational problem for step 2
    a2 = dot(nabla_grad(p), nabla_grad(vp)) * dx
    L2 = dot(nabla_grad(p_1),
             nabla_grad(vp)) * dx - (1 / dt) * div(u_) * vp * dx
    # Define variational problem for step 3
    a3 = dot(u, vu) * dx
    L3 = dot(u_, vu) * dx - dt * dot(nabla_grad(p_ - p_1), vu) * dx
    # Step 4: Transport of rho / Convection-diffusion and SUPG
    vr = vr + tau_SUPG * inner(u_, grad(vr))  # SUPG stabilization
    r_mid = (r + r_1) / 2.0
    F4 = dot((r - r_1) / dt, vr) * dx \
        + dot(dot(u_, grad(r_mid)),  vr) * dx
    if D > 0.0:
        F4 += dot(D * grad(r_mid), grad(vr)) * dx
    # F4 += beta * dot(dot(u_, grad(r_mid)), dot(u_, grad(vr))) * dx
    a4 = lhs(F4)
    L4 = rhs(F4)
    # Assemble matrices
    A1 = assemble(a1)
    A2 = assemble(a2)
    A3 = assemble(a3)
    # A4 = assemble(a4)
    # Apply boundary conditions to matrices
    [bc.apply(A1) for bc in bcu]
    [bc.apply(A2) for bc in bcp]
    return (u_, p_, r_, u_1, p_1, r_1, tau_SUPG, D, L1, a1, L2, A2, L3, A3, L4,
            a4, bcu, bcp, bcr)
def k_normal(k, n):
    return dot(dot(np.transpose(n), k), n)
Example #42
0
Vh = dlfn.FunctionSpace(mesh, P1Curl * P1)
# rhs function
jumpM = dlfn.Constant((0.0, 0.0, -1.0))
# trial functions
A, phi = dlfn.TrialFunctions(Vh)
# test functions
delA, psi = dlfn.TestFunctions(Vh)
# geometric objects
n = dlfn.FacetNormal(mesh)
P = dlfn.Identity(dim) - dlfn.outer(n, n)
# Dirichlet boundary condition on exterior surface
bcA = dlfn.DirichletBC(Vh.sub(0), dlfn.Constant((0.0, 0.0, 0.0)), facetIds,
                       bndryId)
bcPhi = dlfn.DirichletBC(Vh.sub(1), dlfn.Constant(0.0), facetIds, bndryId)
# bilinear form
a = dlfn.dot(dlfn.curl(A), dlfn.curl(delA)) * dV() \
    + dlfn.dot(A, dlfn.grad(psi)) * dV() \
    + dlfn.dot(dlfn.grad(phi), delA) * dV()
# rhs form
l = dlfn.dot(dlfn.cross(n("+"), jumpM("+")), delA("+")) * dA(intrfcId)
# compute solution
sol = dlfn.Function(Vh)
lin_problem = dlfn.LinearVariationalProblem(a, l, sol, bcs=[bcA, bcPhi])
lin_solver = dlfn.LinearVariationalSolver(lin_problem)
lin_solver_parameters = lin_solver.parameters
lin_solver.solve()
# sub solutions
solA = sol.sub(0)
solPhi = sol.sub(1)
# output to pvd
pvd_A = dlfn.File("solution-A.pvd")
Example #43
0
                np.array([1, 2], dtype=np.uintp), theta_p, step)

    if step == 2:
        theta_L.assign(theta_next)

    # Probably can be combined into one file?
    xdmf_u.write(Uh.sub(0), t)
    xdmf_p.write(Uh.sub(1), t)
    del (t1)

timer.stop()

# Compute errors
u_exact.t = t
p_exact.t = t

u_error = sqrt(assemble(dot(Uh.sub(0) - u_exact, Uh.sub(0) - u_exact) * dx))
p_error = sqrt(assemble(dot(Uh.sub(1) - p_exact, Uh.sub(1) - p_exact) * dx))
udiv = sqrt(assemble(div(Uh.sub(0)) * div(Uh.sub(0)) * dx))

momentum = assemble((dot(Uh.sub(0), ex) + dot(Uh.sub(0), ey)) * dx)

if comm.Get_rank() == 0:
    print("Velocity error " + str(u_error))
    print("Pressure error " + str(p_error))
    print("Momentum " + str(momentum))
    print("Divergence " + str(udiv))
    print('Elapsed time ' + str(timer.elapsed()[0]))

list_timings(TimingClear.keep, [TimingType.wall])
Example #44
0
def F(
    u,
    v,
    kappa,
    rho,
    cp,
    convection,
    source,
    r,
    neumann_bcs,
    robin_bcs,
    my_dx,
    my_ds,
    stabilization,
):
    """
    Compute

    .. math::

        F(u) =
            \\int_\\Omega \\kappa r
                \\langle\\nabla u, \\nabla \\frac{v}{\\rho c_p}\\rangle
                \\, 2\\pi \\, \\text{d}x
            + \\int_\\Omega \\langle c, \\nabla u\\rangle v
                \\, 2\\pi r\\,\\text{d}x
            - \\int_\\Omega \\frac{1}{\\rho c_p} f v
                \\, 2\\pi r \\,\\text{d}x\\\\
            - \\int_\\Gamma r \\kappa \\langle n, \\nabla T\\rangle v
                \\frac{1}{\\rho c_p} 2\\pi \\,\\text{d}s
            - \\int_\\Gamma  r \\kappa  \\alpha (u - u_0) v
                \\frac{1}{\\rho c_p} \\, 2\\pi \\,\\text{d}s,

    used for time-stepping

    .. math::

        u' = F(u).
    """
    rho_cp = rho * cp

    F0 = kappa * r * dot(grad(u), grad(v / rho_cp)) * 2 * pi * my_dx

    # F -= dot(b, grad(u)) * v * 2*pi*r * dx_workpiece(0)
    if convection is not None:
        c = as_vector([convection[0], convection[1]])
        F0 += dot(c, grad(u)) * v * 2 * pi * r * my_dx

    # Joule heat
    F0 -= source * v / rho_cp * 2 * pi * r * my_dx

    # Neumann boundary conditions
    for k, n_grad_T in neumann_bcs.items():
        F0 -= r * kappa * n_grad_T * v / rho_cp * 2 * pi * my_ds(k)

    # Robin boundary conditions
    for k, value in robin_bcs.items():
        alpha, u0 = value
        F0 -= r * kappa * alpha * (u - u0) * v / rho_cp * 2 * pi * my_ds(k)

    if stabilization == "supg":
        # Add SUPG stabilization.
        assert convection is not None
        # TODO u_t?
        R = (-div(kappa * r * grad(u)) / rho_cp * 2 * pi +
             dot(c, grad(u)) * 2 * pi * r - source / rho_cp * 2 * pi * r)
        mesh = v.function_space().mesh()
        element_degree = v.ufl_element().degree()
        tau = stab.supg(mesh, convection, kappa, element_degree)
        F0 += R * tau * dot(convection, grad(v)) * my_dx
    else:
        assert stabilization is None

    return F0
        editor.add_cell(k, cell)
    editor.close()
    return mesh


mesh = UnitSquareMesh(200, 200)
# mesh = create_dolfin_mesh(*meshzoo.triangle(1500, corners=[[0, 0], [1, 0], [0, 1]]))

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

u = TrialFunction(V)
v = TestFunction(V)

n = FacetNormal(mesh)
# A = assemble(dot(grad(u), grad(v)) * dx - dot(n, grad(u)) * v * ds)
A = assemble(dot(grad(u), grad(v)) * dx - dot(n, grad(u)) * v * ds)
M = assemble(u * v * dx)

f = Expression("sin(pi * x[0]) * sin(pi * x[1])", element=V.ufl_element())
x = project(f, V)

Ax = A * x.vector()
Minv_Ax = Function(V).vector()
solve(M, Minv_Ax, Ax)
val = Ax.inner(Minv_Ax)

print(val)

# Exact value
x = sympy.Symbol("x")
y = sympy.Symbol("y")
Example #46
0
 def __div__(self, other):
     # We use Claas Abert's 'point measure hack' for the vertex-wise operation.
     a = self.coerce_scalar_field(other)
     w = df.TestFunction(self.functionspace)
     v_res = df.assemble(df.dot(self.f / a.f, w) * df.dP)
     return Field(self.functionspace, value=v_res)
                                         psi_h.cpp_object(), 'gmres',
                                         'hypre_amg')
            # Update old solution
            assign(psi0_h, psi_h)

            # Store
            # if step % store_step is 0 or step is 1:
            output_field << psi_h

        timer.stop()

        # Compute error (we should accurately recover initial condition)
        l2_error = sqrt(
            abs(
                assemble(
                    dot(psi_h - psi0_expression, psi_h - psi0_expression) *
                    dx)))

        # The global mass conservation error should be zero
        area_end = assemble(psi_h * dx)

        if comm.Get_rank() == 0:
            print("l2 error " + str(l2_error))

            # Store in error error table
            num_cells_t = mesh.num_entities_global(2)
            num_particles = len(x)
            area_error_end = np.float64((area_end - area_0))
            with open(output_table, "a") as write_file:
                write_file.write(
                    "%-12.5g %-15d %-20d %-10.2e %-20.3g %-20.3g \n" %
Example #48
0
def h_u(M, u, reg_u=dl.Constant(dl.DOLFIN_SQRT_EPS)):
    """
    Compute the mesh size in the direction u.
    """
    return dl.sqrt(dl.dot(u, u) / (dl.dot(dl.dot(u, M), u) + reg_u))
Example #49
0
    def get_spherical(self):
        """
        Transform magnetisation coordinates to spherical coordinates
        
        theta = arctan(m_r / m_z) ; m_r = sqrt(m_x ^ 2 + m_y ^ 2)
        phi = arctan(m_y / m_x)        

        The theta and phi generalised coordinates are stored in
        self.theta and self.phi respectively.
        
        When this function is called, the two dolfin functions
        are returned

        """

        # Create an scalar Function Space to compute the cylindrical radius (x^2 + y^2)
        # and the angles phi and theta
        S1 = df.FunctionSpace(self.functionspace.mesh(), 'CG', 1)

        # Create a dolfin function from the FS
        m_r = df.Function(S1)
        # Compute the radius using the assemble method with dolfin dP
        # (like a dirac delta to get values on every node of the mesh)
        # This returns a dolfin vector
        cyl_vector = df.assemble(
            df.dot(df.sqrt(self.f[0] * self.f[0] + self.f[1] * self.f[1]),
                   df.TestFunction(S1)) * df.dP, )
        # Set the vector values to the dolfin function
        m_r.vector().set_local(cyl_vector.get_local())

        # Now we compute the theta and phi angles to describe the magnetisation
        # and save them to the coresponding variables
        self.theta = df.Function(S1)
        self.phi = df.Function(S1)

        # We will use the same vector variable than the one used to
        # compute m_r,  in order to save memory

        # Theta = arctan(m_r / m_z)
        cyl_vector = df.assemble(
            df.dot(df.atan_2(m_r, self.f[2]), df.TestFunction(S1)) * df.dP,
            tensor=cyl_vector)

        # Instead of:
        # self.theta.vector().set_local(cyl_vector.get_local())
        # We will use:
        self.theta.vector().axpy(1, cyl_vector)
        # which adds:  1 * cyl_vector
        # to self.theta.vector() and is much faster
        # (we assume self.theta.vector() is empty, i.e. only made of zeros)
        # See: Fenics Book, page 44

        # Phi = arctan(m_y / m_x)
        cyl_vector = df.assemble(
            df.dot(df.atan_2(self.f[1], self.f[0]), df.TestFunction(S1)) *
            df.dP,
            tensor=cyl_vector)

        # We will save this line just in case:
        # self.phi.vector().set_local(cyl_vector.get_local())
        self.phi.vector().axpy(1, cyl_vector)

        return self.theta, self.phi
Example #50
0
def h_linear(integrator_type, mesh, subdomains, boundaries, t_start, dt, T, solution0, \
                 alpha_0, K_0, mu_l_0, lmbda_l_0, Ks_0, \
                 alpha_1, K_1, mu_l_1, lmbda_l_1, Ks_1, \
                 alpha, K, mu_l, lmbda_l, Ks, \
                 cf_0, phi_0, rho_0, mu_0, k_0,\
                 cf_1, phi_1, rho_1, mu_1, k_1,\
                 cf, phi, rho, mu, k, \
                 sigma_v_freeze, dphi_c_dt):
    # Create mesh and define function space
    parameters["ghost_mode"] = "shared_facet"  # required by dS

    dx = Measure('dx', domain=mesh, subdomain_data=subdomains)
    ds = Measure('ds', domain=mesh, subdomain_data=boundaries)
    dS = Measure('dS', domain=mesh, subdomain_data=boundaries)

    BDM = FiniteElement("BDM", mesh.ufl_cell(), 1)
    PDG = FiniteElement("DG", mesh.ufl_cell(), 0)

    BDM_F = FunctionSpace(mesh, BDM)
    PDG_F = FunctionSpace(mesh, PDG)

    W = BlockFunctionSpace([BDM_F, PDG_F], restrict=[None, None])

    TM = TensorFunctionSpace(mesh, 'DG', 0)
    PM = FunctionSpace(mesh, 'DG', 0)
    n = FacetNormal(mesh)
    vc = CellVolume(mesh)
    fc = FacetArea(mesh)

    h = vc / fc
    h_avg = (vc('+') + vc('-')) / (2 * avg(fc))

    I = Identity(mesh.topology().dim())

    monitor_dt = dt

    p_outlet = 0.1e6
    p_inlet = 1000.0

    M_inv = phi_0 * cf + (alpha - phi_0) / Ks

    # Define variational problem
    trial = BlockTrialFunction(W)
    dv, dp = block_split(trial)

    trial_dot = BlockTrialFunction(W)
    dv_dot, dp_dot = block_split(trial_dot)

    test = BlockTestFunction(W)
    psiv, psip = block_split(test)

    block_w = BlockFunction(W)
    v, p = block_split(block_w)

    block_w_dot = BlockFunction(W)
    v_dot, p_dot = block_split(block_w_dot)

    a_time = Constant(0.0) * inner(v_dot, psiv) * dx  #quasi static

    # k is a function of phi
    #k = perm_update_rutqvist_newton(p,p0,phi0,phi,coeff)
    lhs_a = inner(dot(v, mu * inv(k)), psiv) * dx - p * div(
        psiv
    ) * dx  #+ 6.0*inner(psiv,n)*ds(2)  # - inner(gravity*(rho-rho0), psiv)*dx

    b_time = (M_inv + pow(alpha, 2.) / K) * p_dot * psip * dx

    lhs_b = div(v) * psip * dx  #div(rho*v)*psip*dx #TODO rho

    rhs_v = -p_outlet * inner(psiv, n) * ds(3)

    rhs_p = -alpha / K * sigma_v_freeze * psip * dx - dphi_c_dt * psip * dx

    r_u = [lhs_a, lhs_b]

    j_u = block_derivative(r_u, block_w, trial)

    r_u_dot = [a_time, b_time]

    j_u_dot = block_derivative(r_u_dot, block_w_dot, trial_dot)

    r = [r_u_dot[0] + r_u[0] - rhs_v, \
         r_u_dot[1] + r_u[1] - rhs_p]

    def bc(t):
        #bc_v = [DirichletBC(W.sub(0), (.0, .0), boundaries, 4)]
        v1 = DirichletBC(W.sub(0), (1.e-4 * 2.0, 0.0), boundaries, 1)
        v2 = DirichletBC(W.sub(0), (0.0, 0.0), boundaries, 2)
        v4 = DirichletBC(W.sub(0), (0.0, 0.0), boundaries, 4)
        bc_v = [v1, v2, v4]

        return BlockDirichletBC([bc_v, None])

    # Define problem wrapper
    class ProblemWrapper(object):
        def set_time(self, t):
            pass
            #g.t = t

        # Residual and jacobian functions
        def residual_eval(self, t, solution, solution_dot):
            #print(as_backend_type(assemble(p_time - p_time_error)).vec().norm())
            #print("gravity effect", as_backend_type(assemble(inner(gravity*(rho-rho0), psiv)*dx)).vec().norm())

            return r

        def jacobian_eval(self, t, solution, solution_dot,
                          solution_dot_coefficient):
            return [[Constant(solution_dot_coefficient)*j_u_dot[0, 0] + j_u[0, 0], \
                     Constant(solution_dot_coefficient)*j_u_dot[0, 1] + j_u[0, 1]], \
                    [Constant(solution_dot_coefficient)*j_u_dot[1, 0] + j_u[1, 0], \
                     Constant(solution_dot_coefficient)*j_u_dot[1, 1] + j_u[1, 1]]]

        # Define boundary condition
        def bc_eval(self, t):
            return bc(t)

        # Define initial condition
        def ic_eval(self):
            return solution0

        # Define custom monitor to plot the solution
        def monitor(self, t, solution, solution_dot):
            pass

    # Solve the time dependent problem
    problem_wrapper = ProblemWrapper()
    (solution, solution_dot) = (block_w, block_w_dot)
    solver = TimeStepping(problem_wrapper, solution, solution_dot)
    solver.set_parameters({
        "initial_time": t_start,
        "time_step_size": dt,
        "monitor": {
            "time_step_size": monitor_dt,
        },
        "final_time": T,
        "exact_final_time": "stepover",
        "integrator_type": integrator_type,
        "problem_type": "linear",
        "linear_solver": "mumps",
        "report": True
    })
    export_solution = solver.solve()

    return export_solution, T
Example #51
0
def equilibrium_EC(w_, x_, test_functions, solutes, permittivity, mesh, dx, ds,
                   normal, dirichlet_bcs, neumann_bcs, boundary_to_mark,
                   use_iterative_solvers, c_lagrange, V_lagrange, **namespace):
    """ Electrochemistry equilibrium solver. Nonlinear! """
    num_solutes = len(solutes)

    cV = df.split(w_["EC"])
    c, V = cV[:num_solutes], cV[num_solutes]
    if c_lagrange:
        c0, V0 = cV[num_solutes + 1:2 * num_solutes + 1], cV[2 * num_solutes +
                                                             1]
    if V_lagrange:
        V0 = cV[-1]

    b = test_functions["EC"][:num_solutes]
    U = test_functions["EC"][num_solutes]
    if c_lagrange:
        b0, U0 = cV[num_solutes + 1:2 * num_solutes + 1], cV[2 * num_solutes +
                                                             1]
    if V_lagrange:
        U0 = test_functions["EC"][-1]

    phi = x_["phi"]

    q = []
    sum_zx = sum([solute[1] * xj for solute, xj in zip(solutes, composition)])
    for solute, xj in zip(solutes, composition):
        q.append(-xj * Q / (area * sum_zx))

    z = []  # Charge z[species]
    K = []  # Diffusivity K[species]
    beta = []
    for solute in solutes:
        z.append(solute[1])
        K.append(ramp(phi, solute[2:4]))
        beta.append(ramp(phi, solute[4:6]))

    rho_e = sum([c_e * z_e for c_e, z_e in zip(c, z)])
    veps = ramp(phi, permittivity)

    F_c = []
    for ci, bi, c0i, b0i, solute, qi, betai, Ki in zip(c, b, c0, b0, solutes,
                                                       q, beta, K):
        zi = solute[1]
        F_ci = Ki * (df.dot(
            df.grad(bi),
            df.grad(ci) + df.grad(betai) + zi * ci * df.grad(V))) * dx
        if c_lagrange:
            F_ci += b0i * (ci - df.Constant(qi)) * dx + c0i * bi * dx

    F_V = veps * df.dot(df.grad(U), df.grad(V)) * dx
    for boundary_name, sigma_e in neumann_bcs["V"].iteritems():
        F_V += -sigma_e * U * ds(boundary_to_mark[boundary_name])
    if rho_e != 0:
        F_V += -rho_e * U * dx
    if V_lagrange:
        F_V += V0 * U * dx + V * U0 * dx

    F = sum(F_c) + F_V
    J = df.derivative(F, w_["EC"])

    problem = df.NonlinearVariationalProblem(F, w_["EC"], dirichlet_bcs["EC"],
                                             J)
    solver = df.NonlinearVariationalSolver(problem)

    solver.parameters["newton_solver"]["relative_tolerance"] = 1e-7
    if use_iterative_solvers:
        solver.parameters["newton_solver"]["linear_solver"] = "bicgstab"
        if not V_lagrange:
            solver.parameters["newton_solver"]["preconditioner"] = "hypre_amg"

    solver.solve()
Example #52
0
def setup_NS(w_NS, u, p, v, q, p0, q0, dx, ds, normal, dirichlet_bcs,
             neumann_bcs, boundary_to_mark, u_1, phi_, rho_, rho_1, g_, M_,
             mu_, rho_e_, c_, V_, c_1, V_1, dbeta, solutes, per_tau, drho,
             sigma_bar, eps, dveps, grav, enable_PF, enable_EC,
             use_iterative_solvers, use_pressure_stabilization, p_lagrange,
             q_rhs):
    """ Set up the Navier-Stokes subproblem. """
    # F = (
    #     per_tau * rho_ * df.dot(u - u_1, v)*dx
    #     + rho_*df.inner(df.grad(u), df.outer(u_1, v))*dx
    #     + 2*mu_*df.inner(df.sym(df.grad(u)), df.grad(v))*dx
    #     - p * df.div(v)*dx
    #     + df.div(u)*q*dx
    #     - df.dot(rho_*grav, v)*dx
    # )
    mom_1 = rho_1 * u_1
    if enable_PF:
        mom_1 += -M_ * drho * df.nabla_grad(g_)

    F = (per_tau * rho_1 * df.dot(u - u_1, v) * dx + 2 * mu_ *
         df.inner(df.sym(df.nabla_grad(u)), df.sym(df.nabla_grad(v))) * dx -
         p * df.div(v) * dx - q * df.div(u) * dx +
         df.inner(df.nabla_grad(u), df.outer(mom_1, v)) * dx + 0.5 *
         (per_tau * (rho_ - rho_1) * df.dot(u, v) -
          df.dot(mom_1, df.nabla_grad(df.dot(u, v)))) * dx -
         rho_ * df.dot(grav, v) * dx)
    for boundary_name, slip_length in neumann_bcs["u"].iteritems():
        F += 1./slip_length * \
             df.dot(u, v) * ds(boundary_to_mark[boundary_name])

    for boundary_name, pressure in neumann_bcs["p"].iteritems():
        F += pressure * df.inner(normal, v) * ds(
            boundary_to_mark[boundary_name])

    if enable_PF:
        F += phi_ * df.dot(df.grad(g_), v) * dx

    if enable_EC:
        for ci_, ci_1, dbetai, solute in zip(c_, c_1, dbeta, solutes):
            zi = solute[1]
            F += df.dot(df.grad(ci_), v)*dx \
                + zi*ci_1*df.dot(df.grad(V_), v)*dx
            if enable_PF:
                F += ci_ * dbetai * df.dot(df.grad(phi_), v) * dx

    if p_lagrange:
        F += (p * q0 + q * p0) * dx

    if "u" in q_rhs:
        F += -df.dot(q_rhs["u"], v) * dx

    a, L = df.lhs(F), df.rhs(F)

    problem = df.LinearVariationalProblem(a, L, w_NS, dirichlet_bcs)
    solver = df.LinearVariationalSolver(problem)

    if use_iterative_solvers and use_pressure_stabilization:
        solver.parameters["linear_solver"] = "gmres"
        # solver.parameters["preconditioner"] = "ilu"

    return solver
Example #53
0
def run_and_calculate_error(N, dt, tmax, polydeg_u, polydeg_p, nu, last=False):
    """
    Run Ocellaris and return L2 & H1 errors in the last time step
    """
    say(N, dt, tmax, polydeg_u, polydeg_p)

    # Setup and run simulation
    timingtypes = [
        dolfin.TimingType.user, dolfin.TimingType.system,
        dolfin.TimingType.wall
    ]
    dolfin.timings(dolfin.TimingClear_clear, timingtypes)
    sim = Simulation()
    sim.input.read_yaml('disc.inp')

    mesh_type = sim.input.get_value('mesh/type')
    if mesh_type == 'XML':
        # Create unstructured mesh with gmsh
        cmd1 = [
            'gmsh', '-string',
            'lc = %f;' % (3.14 / N), '-o',
            'disc_%d.msh' % N, '-2', 'disc.geo'
        ]
        cmd2 = ['dolfin-convert', 'disc_%d.msh' % N, 'disc.xml']
        with open('/dev/null', 'w') as devnull:
            for cmd in (cmd1, cmd2):
                say(' '.join(cmd))
                subprocess.call(cmd, stdout=devnull, stderr=devnull)
    elif mesh_type == 'UnitDisc':
        sim.input.set_value('mesh/N', N // 2)
    else:
        sim.input.set_value('mesh/Nx', N)
        sim.input.set_value('mesh/Ny', N)

    sim.input.set_value('time/dt', dt)
    sim.input.set_value('time/tmax', tmax)
    sim.input.set_value('solver/polynomial_degree_velocity', polydeg_u)
    sim.input.set_value('solver/polynomial_degree_pressure', polydeg_p)
    sim.input.set_value('physical_properties/nu', nu)
    sim.input.set_value('output/stdout_enabled', False)

    say('Running with %s %s solver ...' %
        (sim.input.get_value('solver/type'),
         sim.input.get_value('solver/function_space_velocity')))
    t1 = time.time()
    setup_simulation(sim)
    run_simulation(sim)
    duration = time.time() - t1
    say('DONE')

    # Interpolate the analytical solution to the same function space
    Vu = sim.data['Vu']
    Vp = sim.data['Vp']
    Vr = sim.data['Vrho']
    polydeg_r = Vr.ufl_element().degree()
    vals = dict(t=sim.time,
                dt=sim.dt,
                Q=sim.input.get_value('user_code/constants/Q'))
    rho_e = dolfin.Expression(
        sim.input.get_value('initial_conditions/rho_p/cpp_code'),
        degree=polydeg_r,
        **vals)
    u0e = dolfin.Expression(
        sim.input.get_value('initial_conditions/up0/cpp_code'),
        degree=polydeg_u,
        **vals)
    u1e = dolfin.Expression(
        sim.input.get_value('initial_conditions/up1/cpp_code'),
        degree=polydeg_u,
        **vals)
    pe = dolfin.Expression(
        sim.input.get_value('initial_conditions/p/cpp_code'),
        degree=polydeg_p,
        **vals)

    rho_a = dolfin.project(rho_e, Vr)
    u0a = dolfin.project(u0e, Vu)
    u1a = dolfin.project(u1e, Vu)
    pa = dolfin.project(pe, Vp)

    mesh = sim.data['mesh']
    n = dolfin.FacetNormal(mesh)

    # Correct for possible non-zero average p
    int_p = dolfin.assemble(sim.data['p'] * dolfin.dx)
    int_pa = dolfin.assemble(pa * dolfin.dx)
    vol = dolfin.assemble(dolfin.Constant(1.0) * dolfin.dx(domain=mesh))
    pa_avg = int_pa / vol
    sim.data['p'].vector()[:] += pa_avg

    # Calculate L2 errors
    err_rho = calc_err(sim.data['rho'], rho_a)
    err_u0 = calc_err(sim.data['u0'], u0a)
    err_u1 = calc_err(sim.data['u1'], u1a)
    err_p = calc_err(sim.data['p'], pa)

    # Calculate H1 errors
    err_rho_H1 = calc_err(sim.data['rho'], rho_a, 'H1')
    err_u0_H1 = calc_err(sim.data['u0'], u0a, 'H1')
    err_u1_H1 = calc_err(sim.data['u1'], u1a, 'H1')
    err_p_H1 = calc_err(sim.data['p'], pa, 'H1')

    reports = sim.reporting.timestep_xy_reports
    say('Num time steps:', sim.timestep)
    say('Num cells:', mesh.num_cells())
    Co_max, Pe_max = numpy.max(reports['Co']), numpy.max(reports['Pe'])
    say('Co_max:', Co_max)
    say('Pe_max:', Pe_max)
    say('rho_min went from %r to %r' %
        (reports['min(rho)'][0], reports['min(rho)'][-1]))
    say('rho_max went from %r to %r' %
        (reports['max(rho)'][0], reports['max(rho)'][-1]))
    m0, m1 = reports['mass'][0], reports['mass'][-1]
    say('mass error %.3e (%.3e)' % (m1 - m0, (m1 - m0) / m0))
    say('vel repr error %.3e' %
        dolfin.assemble(dolfin.dot(sim.data['u'], n) * dolfin.ds))
    say('p*dx', int_p)
    div_u_Vp = abs(
        dolfin.project(dolfin.div(sim.data['u']),
                       Vp).vector().get_local()).max()
    say('div(u)|Vp', div_u_Vp)
    div_u_Vu = abs(
        dolfin.project(dolfin.div(sim.data['u']),
                       Vu).vector().get_local()).max()
    say('div(u)|Vu', div_u_Vu)
    Vdg0 = dolfin.FunctionSpace(mesh, "DG", 0)
    div_u_DG0 = abs(
        dolfin.project(dolfin.div(sim.data['u']),
                       Vdg0).vector().get_local()).max()
    say('div(u)|DG0', div_u_DG0)
    Vdg1 = dolfin.FunctionSpace(mesh, "DG", 1)
    div_u_DG1 = abs(
        dolfin.project(dolfin.div(sim.data['u']),
                       Vdg1).vector().get_local()).max()
    say('div(u)|DG1', div_u_DG1)

    isoparam = mesh.ufl_coordinate_element().degree() > 1
    allways_plot = True
    if (last or allways_plot) and (
            not isoparam or sim.input.get_value('mesh/type') == 'UnitDisc'):
        # Plot the results
        for fa, name in ((u0a, 'u0'), (u1a, 'u1'), (pa, 'p'), (rho_a, 'rho')):
            fh = sim.data[name]
            if isoparam:
                # Bug in matplotlib plotting for isoparametric elements
                mesh2 = dolfin.UnitDiscMesh(dolfin.MPI.comm_world, N // 2, 1,
                                            2)
                ue = fa.function_space().ufl_element()
                V2 = dolfin.FunctionSpace(mesh2, ue.family(), ue.degree())
                fa2, fh2 = dolfin.Function(V2), dolfin.Function(V2)
                fa2.vector().set_local(fa.vector().get_local())
                fh2.vector().set_local(fh.vector().get_local())
                fa, fh = fa2, fh2
            discr = ''  # '%g_%g_' % (N, dt)
            plot(fa, name + ' analytical', '%s%s_1analytical' % (discr, name))
            plot(fh, name + ' numerical', '%s%s_2numerical' % (discr, name))
            plot(fh - fa, name + ' diff', '%s%s_3diff' % (discr, name))

    hmin = mesh.hmin()
    return err_rho, err_u0, err_u1, err_p, err_rho_H1, err_u0_H1, err_u1_H1, err_p_H1, hmin, dt, Co_max, Pe_max, duration
Example #54
0
    def __init__(self, V, viscosity=1e-2, penalty=1e5):
        '''
        Parameters
        ----------
        V : dolfin.FunctionSpace
            Function space for the distance function.
        viscosity: float or dolfin.Constant
            Stabilization for the unique solution of the distance problem.
        penalty: float or dolfin.Constant
            Penalty for weakly enforcing the zero-distance boundary conditions.

        '''

        if not isinstance(V, dolfin.FunctionSpace):
            raise TypeError('Parameter `V` must be a `dolfin.FunctionSpace`')

        if not isinstance(viscosity, Constant):
            if not isinstance(viscosity, (float, int)):
                raise TypeError('`Parameter `viscosity`')
            viscosity = Constant(viscosity)

        if not isinstance(penalty, Constant):
            if not isinstance(penalty, (float, int)):
                raise TypeError('Parameter `penalty`')
            penalty = Constant(penalty)

        self._viscosity = viscosity
        self._penalty = penalty

        mesh = V.mesh()
        xs = mesh.coordinates()
        l0 = (xs.max(0) - xs.min(0)).min()

        self._d = d = Function(V)
        self._Q = dolfin.FunctionSpace(mesh, 'DG', 0)

        self._mf = dolfin.MeshFunction('size_t', mesh,
                                       mesh.geometric_dimension())
        self._dx_penalty = dx(subdomain_id=1,
                              subdomain_data=self._mf,
                              domain=mesh)

        v0 = dolfin.TestFunction(V)
        v1 = dolfin.TrialFunction(V)

        target_gradient = Constant(1.0)
        scaled_penalty = penalty / mesh.hmax()

        lhs_F0 = l0*dot(grad(v0), grad(v1))*dx \
            + scaled_penalty*v0*v1*self._dx_penalty

        rhs_F0 = v0 * target_gradient * dx

        problem = dolfin.LinearVariationalProblem(lhs_F0, rhs_F0, d)
        self._linear_solver = dolfin.LinearVariationalSolver(problem)
        self._linear_solver.parameters["symmetric"] = True

        F = v0*(grad(d)**2-target_gradient)*dx \
            + viscosity*l0*dot(grad(v0), grad(d))*dx \
            + scaled_penalty*v0*d*self._dx_penalty

        J = dolfin.derivative(F, d, v1)

        problem = dolfin.NonlinearVariationalProblem(F, d, bcs=None, J=J)
        self._nonlinear_solver = dolfin.NonlinearVariationalSolver(problem)
        self._nonlinear_solver.parameters['nonlinear_solver'] = 'newton'
        self._nonlinear_solver.parameters['symmetric'] = False

        self._solve_initdist_problem = self._linear_solver.solve
        self._solve_distance_problem = self._nonlinear_solver.solve
Example #55
0
@function.expression.numba_eval
def ui_eval(values, x, cell_idx):
    values[:, 0] = np.exp(1.0j * k0 *
                          (np.cos(theta) * x[:, 0] + np.sin(theta) * x[:, 1]))


# Test and trial function space
V = FunctionSpace(mesh, ("Lagrange", deg))

# Prepare Expression as FE function
ui = interpolate(Expression(ui_eval), V)

# Define variational problem
u = TrialFunction(V)
v = TestFunction(V)
g = dot(grad(ui), n) + 1j * k0 * ui
a = inner(grad(u), grad(v)) * dx - k0**2 * inner(u, v) * dx + 1j * k0 * inner(
    u, v) * ds
L = inner(g, v) * ds

# Compute solution
u = Function(V)
solve(a == L, u, [])

# Save solution in XDMF format (to be viewed in Paraview, for example)
with XDMFFile(MPI.comm_world,
              "plane_wave.xdmf",
              encoding=XDMFFile.Encoding.HDF5) as file:
    file.write(u)
"""Calculate L2 and H1 errors of FEM solution and best approximation.
This demonstrates the error bounds given in Ihlenburg. Pollution errors
Example #56
0
 def update_charge(self, phi):
     bnd_id = self.domain_args[1]
     projection = df.dot(df.grad(phi), self.n) * self.dss(bnd_id)
     self.charge = df.assemble(projection)
     return self.charge
Example #57
0
    def setup_scalar_equation(self):
        sim = self.simulation
        V = sim.data['Vphi']
        mesh = V.mesh()
        P = V.ufl_element().degree()

        # Source term
        source_cpp = sim.input.get_value('solver/source', '0', 'string')
        f = dolfin.Expression(source_cpp, degree=P)

        # Create the solution function
        sim.data['phi'] = dolfin.Function(V)

        # DG elliptic penalty
        penalty = define_penalty(mesh, P, k_min=1.0, k_max=1.0)
        penalty_dS = dolfin.Constant(penalty)
        penalty_ds = dolfin.Constant(penalty * 2)
        yh = dolfin.Constant(1 / (penalty * 2))

        # Define weak form
        u, v = dolfin.TrialFunction(V), dolfin.TestFunction(V)
        a = dot(grad(u), grad(v)) * dx
        L = f * v * dx

        # Symmetric Interior Penalty method for -∇⋅∇φ
        n = dolfin.FacetNormal(mesh)
        a -= dot(n('+'), avg(grad(u))) * jump(v) * dS
        a -= dot(n('+'), avg(grad(v))) * jump(u) * dS

        # Symmetric Interior Penalty coercivity term
        a += penalty_dS * jump(u) * jump(v) * dS

        # Dirichlet boundary conditions
        # Nitsche's (1971) method, see e.g. Epshteyn and Rivière (2007)
        dirichlet_bcs = sim.data['dirichlet_bcs'].get('phi', [])
        for dbc in dirichlet_bcs:
            bcval, dds = dbc.func(), dbc.ds()

            # SIPG for -∇⋅∇φ
            a -= dot(n, grad(u)) * v * dds
            a -= dot(n, grad(v)) * u * dds
            L -= dot(n, grad(v)) * bcval * dds

            # Weak Dirichlet
            a += penalty_ds * u * v * dds
            L += penalty_ds * bcval * v * dds

        # Neumann boundary conditions
        neumann_bcs = sim.data['neumann_bcs'].get('phi', [])
        for nbc in neumann_bcs:
            L += nbc.func() * v * nbc.ds()

        # Robin boundary conditions
        # See Juntunen and Stenberg (2009)
        # n⋅∇φ = (φ0 - φ)/b + g
        robin_bcs = sim.data['robin_bcs'].get('phi', [])
        for rbc in robin_bcs:
            b, rds = rbc.blend(), rbc.ds()
            dval, nval = rbc.dfunc(), rbc.nfunc()

            # From IBP of the main equation
            a -= dot(n, grad(u)) * v * rds

            # Test functions for the Robin BC
            z1 = 1 / (b + yh) * v
            z2 = -yh / (b + yh) * dot(n, grad(v))

            # Robin BC added twice with different test functions
            for z in [z1, z2]:
                a += b * dot(n, grad(u)) * z * rds
                a += u * z * rds
                L += dval * z * rds
                L += b * nval * z * rds

        # Does the system have a null-space?
        self.has_null_space = len(dirichlet_bcs) + len(robin_bcs) == 0

        self.form_lhs = a
        self.form_rhs = L
Example #58
0
    def __init__(self, Vh, covariance, mean=None):
        """
        Constructor

        Inputs:
        - :code:`Vh`:             Finite element space on which the prior is
                                  defined. Must be the Real space with one global 
                                  degree of freedom
        - :code:`covariance`:     The covariance of the prior. Must be a
                                  :code:`numpy.ndarray` of appropriate size
        - :code:`mean`(optional): Mean of the prior distribution. Must be of
                                  type `dolfin.Vector()`
        """

        self.Vh = Vh

        if Vh.dim() != covariance.shape[0] or Vh.dim() != covariance.shape[1]:
            raise ValueError(
                "Covariance incompatible with Finite Element space")

        if not np.issubdtype(covariance.dtype, np.floating):
            raise TypeError("Covariance matrix must be a float array")

        self.covariance = covariance

        #np.linalg.cholesky automatically provides more error checking,
        #so use those
        self.chol = np.linalg.cholesky(self.covariance)

        self.chol_inv = scila.solve_triangular(self.chol,
                                               np.identity(Vh.dim()),
                                               lower=True)

        self.precision = np.dot(self.chol_inv.T, self.chol_inv)

        trial = dl.TrialFunction(Vh)
        test = dl.TestFunction(Vh)

        domain_measure_inv = dl.Constant(1.0 \
                                / dl.assemble(dl.Constant(1.) * dl.dx(Vh.mesh())))

        #Identity mass matrix
        self.M = dl.assemble(domain_measure_inv * dl.inner(trial, test) *
                             dl.dx)
        self.Msolver = Operator2Solver(self.M)

        if mean:
            self.mean = mean
        else:
            tmp = dl.Vector()
            self.M.init_vector(tmp, 0)
            tmp.zero()
            self.mean = tmp

        if Vh.dim() == 1:
            trial = dl.as_matrix([[trial]])
            test = dl.as_matrix([[test]])

        #Create form matrices
        covariance_op = dl.as_matrix(list(map(list, self.covariance)))
        precision_op = dl.as_matrix(list(map(list, self.precision)))
        chol_op = dl.as_matrix(list(map(list, self.chol)))
        chol_inv_op = dl.as_matrix(list(map(list, self.chol_inv)))

        #variational for the regularization operator, or the precision matrix
        var_form_R = domain_measure_inv \
                     * dl.inner(test, dl.dot(precision_op, trial)) * dl.dx

        #variational for the inverse regularization operator, or the covariance
        #matrix
        var_form_Rinv = domain_measure_inv \
                        * dl.inner(test, dl.dot(covariance_op, trial)) * dl.dx

        #variational form for the square root of the regularization operator
        var_form_R_sqrt = domain_measure_inv \
                          * dl.inner(test, dl.dot(chol_inv_op.T, trial)) * dl.dx

        #variational form for the square root of the inverse regularization
        #operator
        var_form_Rinv_sqrt = domain_measure_inv \
                             * dl.inner(test, dl.dot(chol_op, trial)) * dl.dx

        self.R = dl.assemble(var_form_R)
        self.RSolverOp = dl.assemble(var_form_Rinv)
        self.Rsolver = Operator2Solver(self.RSolverOp)
        self.sqrtR = dl.assemble(var_form_R_sqrt)
        self.sqrtRinv = dl.assemble(var_form_Rinv_sqrt)
Example #59
0
def end_hook(x_, enable_NS, dx, **namespace):
    u_norm = 0.
    if enable_NS:
        u_norm = df.assemble(df.dot(x_["u"], x_["u"])*dx)
    info("Velocity norm = {:e}".format(u_norm))
Example #60
0
 def assemble_laplacian(self):
     print("Assembling laplacians")
     # laplacian discretisation
     self.laplacian = assemble(dot(grad(self.w), grad(self.u)) * dx)