def solve_nonlinear_dynamic(component, t0, t_end):
system, formulation = create_mechanical_system(
component,
constant_mass=True,
constant_damping=True,
constraint_formulation='boolean')
solfac = SolverFactory()
solfac.set_system(system)
solfac.set_analysis_type('transient')
solfac.set_integrator('genalpha')
solfac.set_large_deflection(True)
solfac.set_nonlinear_solver('newton')
solfac.set_linear_solver('scipy-sparse')
solfac.set_acceleration_intializer('zero')
solfac.set_newton_maxiter(30)
solfac.set_newton_atol(1e-6)
solfac.set_newton_rtol(1e-8)
solfac.set_dt_initial(0.001)
solver = solfac.create_solver()
solution_writer = AmfeSolution()
def write_callback(t, x, dx, ddx):
u, du, ddu = formulation.recover(x, dx, ddx, t)
solution_writer.write_timestep(t, u, None, None)
no_of_dofs = system.dimension
q0 = np.zeros(no_of_dofs)
dq0 = q0
solver.solve(write_callback, t0, q0, dq0, t_end)
return solution_writer
def solve_nonlinear_static(system, formulation, component, load_steps):
"""
Solves a MechanicalSystem using a nonlinear static method using newton for the nonlinear solver.
The deformation is divided into an amount of intermediate steps which are defined in the number of load_steps.
Parameters
----------
system : MechanicalSystem
Created MechanicalSystem object describing the Structural Component
formulation : ConstraintFormulation
A ConstraintFormulation object that can recover the nodal unconstrained displacements of the component
from the constrained states of the system
component : StructuralComponent
StructuralComponent belonging to the system
load_steps : int
Number of load steps used for the solution
Returns
-------
solution : amfe.solution.AmfeSolution
Simple Container for solutions of AMfe simulations
"""
solfac = SolverFactory()
solfac.set_system(system)
solfac.set_analysis_type('static')
solfac.set_nonlinear_solver('newton')
solfac.set_linear_solver('scipy-sparse')
solfac.set_acceleration_intializer('zero')
solfac.set_newton_maxiter(10)
solfac.set_newton_atol(1e-8)
solfac.set_newton_rtol(2e-9)
solfac.set_dt_initial(1.0 / load_steps)
solver = solfac.create_solver()
solution_writer = AmfeSolution()
no_of_dofs = system.dimension
q0 = np.zeros(no_of_dofs)
dq0 = q0
t0 = 0.0
t_end = 1.0
def write_callback(t, x, dx, ddx):
if isclose(t, t_end):
u, du, ddu = formulation.recover(x, dx, ddx, t)
strains, stresses = component.strains_and_stresses(u, du, t)
solution_writer.write_timestep(t, u, None, None, strains, stresses)
solver.solve(write_callback, t0, q0, dq0, t_end)
print('Solution finished')
return solution_writer
# ----------------------------------------- NONLINEAR DYNAMIC ANALYSIS ------------------------------------------------
system, formulation = create_constrained_mechanical_system_from_component(my_component, constant_mass=True,
constant_damping=True,
constraint_formulation='lagrange',
scaling=10.0, penalty=3.0)
solfac = SolverFactory()
solfac.set_system(system)
solfac.set_analysis_type('transient')
solfac.set_integrator('genalpha')
solfac.set_nonlinear_solver('newton')
solfac.set_linear_solver('scipy-sparse')
solfac.set_acceleration_intializer('zero')
solfac.set_newton_maxiter(20)
solfac.set_newton_atol(1e-8)
solfac.set_newton_rtol(1e-9)
solfac.set_dt_initial(0.00001)
solfac._alpha_f = 0.25
solfac._alpha_m = 0.25
solfac._gamma = 0.75
solfac._beta = 0.390625
residuals = list()
mysolver = solfac.create_solver()
writer = AmfeSolution()
def solve_nonlinear_dynamic(system,
formulation,
component,
t0,
t_end,
dt,
write_each=1):
"""
Solves a system
Parameters
----------
system : MechanicalSystem
Created MechanicalSystem object describing the Structural Component
formulation : ConstraintFormulation
A ConstraintFormulation object that can recover the nodal unconstrained displacements of the component
from the constrained states of the system
component : StructuralComponent
StructuralComponent belonging to the system
t0 : float
initial time
t_end : float
final time
dt : float
increment between time steps
write_each : int
Specifies that the solver writes every n'th solution (eg. type 2 to write every second timestep)
Returns
-------
solution : amfe.solution.AmfeSolution
Simple Container for solutions of AMfe simulations
"""
solfac = SolverFactory()
solfac.set_system(system)
solfac.set_analysis_type('transient')
solfac.set_integrator('genalpha')
solfac.set_nonlinear_solver('newton')
solfac.set_linear_solver('scipy-sparse')
solfac.set_acceleration_intializer('zero')
solfac.set_newton_maxiter(10)
solfac.set_newton_atol(1e-8)
solfac.set_newton_rtol(2e-11)
solfac.set_dt_initial(dt)
solver = solfac.create_solver()
solution_writer = AmfeSolution()
def write_callback(t, x, dx, ddx):
cur_ts = int((t - t0) // dt)
if abs(cur_ts % write_each) <= 1e-7:
u, du, ddu = formulation.recover(x, dx, ddx, t)
strains, stresses = component.strains_and_stresses(u, du, t)
solution_writer.write_timestep(t, u, du, ddu, strains, stresses)
no_of_dofs = system.dimension
q0 = np.zeros(no_of_dofs)
dq0 = q0
solver.solve(write_callback, t0, q0, dq0, t_end)
print('Solution finished')
return solution_writer