import numpy as np
import sharpy.structure.utils.xbeamlib as xbeamlib
import sharpy.utils.cout_utils as cout
import sharpy.utils.settings as settings
from sharpy.utils.solver_interface import solver, BaseSolver, solver_from_string
import sharpy.utils.algebra as algebra
_BaseStructural = solver_from_string('_BaseStructural')
[docs]@solver
class NonLinearStatic(_BaseStructural):
"""
Structural solver used for the static simulation of free-flying structures.
This solver provides an interface to the structural library (``xbeam``) and updates the structural parameters
for every k-th step of the FSI iteration.
This solver can be called as part of a standalone structural simulation or as the structural solver of a coupled
static aeroelastic simulation.
"""
solver_id = 'NonLinearStatic'
solver_classification = 'structural'
# settings list
settings_types = _BaseStructural.settings_types.copy()
settings_default = _BaseStructural.settings_default.copy()
settings_description = _BaseStructural.settings_description.copy()
settings_types['initial_position'] = 'list(float)'
settings_default['initial_position'] = np.array([0.0, 0.0, 0.0])
settings_table = settings.SettingsTable()
__doc__ += settings_table.generate(settings_types, settings_default, settings_description)
def __init__(self):
self.data = None
self.settings = None
def initialise(self, data, custom_settings=None):
self.data = data
if custom_settings is None:
self.settings = data.settings[self.solver_id]
else:
self.settings = custom_settings
settings.to_custom_types(self.settings, self.settings_types, self.settings_default)
def run(self):
self.data.structure.timestep_info[self.data.ts].for_pos[0:3] = self.settings['initial_position']
xbeamlib.cbeam3_solv_nlnstatic(self.data.structure, self.settings, self.data.ts)
self.extract_resultants()
return self.data
def next_step(self):
self.data.structure.next_step()
def extract_resultants(self, tstep=None):
if tstep is None:
tstep = self.data.structure.timestep_info[self.data.ts]
applied_forces = self.data.structure.nodal_b_for_2_a_for(tstep.steady_applied_forces,
tstep)
applied_forces_copy = applied_forces.copy()
gravity_forces_copy = tstep.gravity_forces.copy()
for i_node in range(self.data.structure.num_node):
applied_forces_copy[i_node, 3:6] += algebra.cross3(tstep.pos[i_node, :],
applied_forces_copy[i_node, 0:3])
gravity_forces_copy[i_node, 3:6] += algebra.cross3(tstep.pos[i_node, :],
gravity_forces_copy[i_node, 0:3])
totals = np.sum(applied_forces_copy + gravity_forces_copy, axis=0)
return totals[0:3], totals[3:6]
def update(self, tstep=None):
self.create_q_vector(tstep)
def create_q_vector(self, tstep=None):
import sharpy.structure.utils.xbeamlib as xb
if tstep is None:
tstep = self.data.structure.timestep_info[-1]
xb.xbeam_solv_disp2state(self.data.structure, tstep)