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import math
class ParameterSet(dict):
def __init__(self, *args, **kwargs):
super(ParameterSet, self).__init__(*args, **kwargs)
self.__dict__ = self
parameterSet = ParameterSet()
#############################################
# Grid parameters
#############################################
parameterSet.structuredGrid = "cube"
parameterSet.lower = "0 0"
parameterSet.upper = "0.38 0.128"
parameterSet.elements = "15 5"
# Number of grid levels
parameterSet.numLevels = 1
#############################################
# Solver parameters
#############################################
# Number of homotopy steps for the Dirichlet boundary conditions
parameterSet.numHomotopySteps = 1
# Tolerance of the trust region solver
parameterSet.tolerance = 1e-8
# Max number of steps of the trust region solver
parameterSet.maxSolverSteps = 500
parameterSet.solverScaling = "1 1 1 0.01 0.01 0.01"
# Initial trust-region radius
parameterSet.initialTrustRegionRadius = 0.001
# Number of multigrid iterations per trust-region step
parameterSet.numIt = 200
# Number of presmoothing steps
parameterSet.nu1 = 3
# Number of postsmoothing steps
parameterSet.nu2 = 3
# Number of coarse grid corrections
parameterSet.mu = 1
# Number of base solver iterations
parameterSet.baseIt = 100
# Tolerance of the multigrid solver
parameterSet.mgTolerance = 1e-7
# Tolerance of the base grid solver
parameterSet.baseTolerance = 1e-8
# Measure convergence
parameterSet.instrumented = 0
############################
# Material parameters
############################
# Parameters for the shearing/wrinkling example from Wong/Pellegrino 2006
# We use 'meters' as the length unit
parameterSet.materialParameters = ParameterSet()
# shell thickness
parameterSet.materialParameters.thickness = 2.5e-5
# Lame parameters
# corresponds to E = 3.5GPa, nu=0.31
parameterSet.materialParameters.mu = 5.6452e+09
parameterSet.materialParameters["lambda"] = 2.1796e+09
# Cosserat couple modulus
parameterSet.materialParameters.mu_c = 0
# Length scale parameter
parameterSet.materialParameters.L_c = 2.5e-8
# Curvature exponent
parameterSet.materialParameters.q = 2
# Shear correction factor
parameterSet.materialParameters.kappa = 1
# TODO: These three parameters are not actually used,
# but the current implementation requires them nevertheless.
parameterSet.materialParameters.b1 = 1
parameterSet.materialParameters.b2 = 1
parameterSet.materialParameters.b3 = 1
#############################################
# Boundary values
#############################################
parameterSet.problem = "wong-pellegrino"
### Python predicate specifying all Dirichlet grid vertices
# x is the vertex coordinate
parameterSet.dirichletVerticesPredicate = "[x[1] < 0.0001 or x[1] > 0.128 - 0.0001, x[1] < 0.0001 or x[1] > 0.128 - 0.0001, x[1] < 0.0001 or x[1] > 0.128 - 0.0001]"
parameterSet.dirichletRotationVerticesPredicate = "x[1] < 0.0001 or x[1] > 0.128 - 0.0001"
# Initial deformation
#parameterSet.startFromFile = True
parameterSet.initialIterateFilename = "cosserat_iterate_2.vtu"
parameterSet.initialDeformation = "[x[0] + 0.003*x[1] / 0.128, x[1], 0.002*math.cos(1e4*x[0])]"