def rho(x):
return 8.0
def modulus(x):
return rho(x) * (target_vp ** 2)
def eta(x):
return 2.0 * modulus(x) * target_vp * target_law_coef
# Creating left dirichlet boundary condition.
left_bc = configuration.BoundaryCondition(boundary_condition_type=configuration.BoundaryConditionType.DIRICHLET,
value=lambda t: functional.ricker(t - src_offset, central_frequency))
absorbing_param = np.sqrt(rho(0.) * modulus(0.))
right_bc = configuration.BoundaryCondition(boundary_condition_type=configuration.BoundaryConditionType.ABSORBING,
value=lambda t: 0, param=absorbing_param)
# Creating configuration.
config = configuration.ViscoElasticKelvinVoigt(density=rho, modulus=modulus, eta=eta, left_bc=left_bc,
right_bc=right_bc)
# Creating finite element space.
fe_space = fe_sp.FiniteElementSpace(mesh=mesh.make_mesh_from_npt(0.0, 10.0, 300), fe_order=5, quad_order=5)
# Creating propagator.
propag = visco_elastic_kelvin_voigt_propagator.ViscoElasticKelvinVoigt(config=config, fe_space=fe_space)
return 2.0 + 1.0 * np.exp(-1000 * (x - 0.3)**2)
def alpha(x):
c = celerity(x)
c2 = c * c
return 1.0 / c2
def beta(x):
return 2.0
# Creating left robin boundary condition.
left_bc = configuration.BoundaryCondition(
boundary_condition_type=configuration.BoundaryConditionType.DIRICHLET,
value=lambda t: functional.ricker(t - 0.4, 25.0))
absorbing_param = np.sqrt(beta(1.5) * alpha(1.5))
right_bc = configuration.BoundaryCondition(
boundary_condition_type=configuration.BoundaryConditionType.ABSORBING,
value=lambda t: 0,
param=absorbing_param)
# Creating configuration.
config = configuration.Elastic(alpha=alpha,
beta=beta,
left_bc=left_bc,
right_bc=right_bc)
# Creating finite element space.
# definition of material parameters for KV model.
rho = 8.0
C = 288.0
D = 0.1
VP = np.sqrt(C / rho)
# definition of material parameters for Zener model.
k1, k2, eta = kelvin_voigt_to_zener(C, D, target_w)
# Creating finite element space.
fe_space = fe_sp.FiniteElementSpace(mesh=mesh.make_mesh_from_npt(0.0, 30.0, 900), fe_order=5, quad_order=5)
# Creating boundary conditions.
if wide_band_src is False:
left_bc = configuration.BoundaryCondition(boundary_condition_type=configuration.BoundaryConditionType.DIRICHLET,
value=lambda t: functional.gated_cosine(t - narrow_band_offset, central_frequency, narrow_band_std_dev))
elif wide_band_src is True:
left_bc = configuration.BoundaryCondition(boundary_condition_type=configuration.BoundaryConditionType.DIRICHLET,
value=lambda t: functional.ricker(t - wide_band_offset, central_frequency))
absorbing_param = np.sqrt(rho * C)
right_bc = configuration.BoundaryCondition(boundary_condition_type=configuration.BoundaryConditionType.ABSORBING,
value=lambda t: 0, param=absorbing_param)
# Creating configurations.
config_KV = configuration.ViscoElasticKelvinVoigt(density=lambda x: rho, modulus=lambda x: C, eta=lambda x: D,
left_bc=left_bc, right_bc=right_bc)
config_Z = configuration.ViscoElasticZener(density=lambda x: rho, modulus1=lambda x: k1, modulus2=lambda x: k2,
eta=lambda x: eta, left_bc=left_bc, right_bc=right_bc)
def alpha(x):
return 1.0
def beta(x, theta):
return theta
true_beta = partial(beta, theta=THETA_BAR)
# Creating configuration.
# We don't need to specify a right boundary condition since the natural boundary condition is zero derivative,
# which is what we want.
left_bc = configuration.BoundaryCondition(
boundary_condition_type=configuration.BoundaryConditionType.ROBIN,
param=0.0,
value=lambda t: ricker(t - 2.4, 2.0))
config_theta_bar = configuration.Elastic(alpha=alpha,
beta=true_beta,
left_bc=left_bc)
fe_space = fe_sp.FiniteElementSpace(mesh=mesh.make_mesh_from_npt(
0.0, 1.5, 200),
fe_order=5,
quad_order=5)
propag = elastic_propagator.Elastic(
config=config_theta_bar,
fe_space=fe_space,
mass_assembly_type=fe_op.AssemblyType.LUMPED,