How to extract rotational displacements on a static analysis ?

Pernelle Marone-Hitz

How can I extract the rotational displacement values from the result file of a static structural analysis using PyDPF?

Pernelle Marone-Hitz

raw_displacement operator can be used for that purpose. Please note that the data contained in raw_displacement will depend on the types of elements used, the type of analysis, whether the model is 2D or 3D, etc.

Below is an example:

import ansys.dpf.core as dpf
import numpy as np


rstfile = r'D:/nodal_solution/file.rst'
datfile = r'D:/nodal_solution/ds.dat'


substep = 4


# create the DataSource
ds = dpf.DataSources()
ds.set_result_file_path(rstfile, key="rst")
ds.add_file_path(datfile, key="dat")


# instantiate a Model
model = dpf.Model(data_sources=ds)
print(model)


# define a time_scoping on substep 4
time_scoping = dpf.time_freq_scoping_factory.scoping_by_step_and_substep_from_model(
    load_step_id=1,
    subset_id=substep,
    model=model
)


# extract the raw displacements
displacement_fc = dpf.operators.result.raw_displacement(
    time_scoping=time_scoping,
    data_sources=model,
).eval()
print(displacement_fc)


# extract the field from the fields_container
disp_field = displacement_fc[0]
print(disp_field)


# one can access the field's underlying numpy.ndarray using ".data"
print(disp_field.data)


# save to csv
np.savetxt(
    'displacement2_pydpf-core.csv',
    X=disp_field.data,
    delimiter=',',  comments='', fmt='%.18e',
    header="UX, UY, UZ, RX, RY, RZ"
)


# optional: extract the rotational dofs from the field
rotational_disp = dpf.operators.logic.component_selector(
    field=disp_field,
    component_number=[3, 4, 5]
).eval()
print(rotational_disp)