Material properties and custom failure criterion

This example shows how to access constant material properties and how to implement a custom failure criterion. The failure criterion is computed for all layers and integration points. Finally, the elemental maximum is computed and shown.

Note

Only constant material properties are currently supported.

Note

When using a Workbench project, use the get_composite_files_from_workbench_result_folder() method to obtain the input files.

Script

Import dependencies

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

from ansys.dpf.composites.composite_model import CompositeModel
from ansys.dpf.composites.constants import Sym3x3TensorComponent
from ansys.dpf.composites.example_helper import get_continuous_fiber_example_files
from ansys.dpf.composites.layup_info.material_properties import MaterialProperty
from ansys.dpf.composites.select_indices import get_selected_indices
from ansys.dpf.composites.server_helpers import connect_to_or_start_server

Start a server and get the examples files. This will copy the example files into the current working directory.

server = connect_to_or_start_server()
composite_files_on_server = get_continuous_fiber_example_files(server, "shell")

Set up the composite model

composite_model = CompositeModel(composite_files_on_server, server)

Get dictionary that maps dpf_material_id to properties The creation of the dictionary is currently quite slow and should be done before using the properties in a loop. Currently only constant properties are supported. For variable material properties, the default value is returned.

material_property = MaterialProperty.Strain_Limits_eXt
property_dict = composite_model.get_constant_property_dict([material_property])

Get strain field

strain_operator = composite_model.core_model.results.elastic_strain()
strain_operator.inputs.bool_rotate_to_global(False)
strain_field = strain_operator.get_output(pin=0, output_type=dpf.types.fields_container)[0]

Implement a custom failure criterion: basic max strain

result_field = dpf.field.Field(location=dpf.locations.elemental, nature=dpf.natures.scalar)

with result_field.as_local_field() as local_result_field:
    component = Sym3x3TensorComponent.TENSOR11

    for element_id in strain_field.scoping.ids:
        strain_data = strain_field.get_entity_data_by_id(element_id)
        element_info = composite_model.get_element_info(element_id)
        element_max = 0
        for layer_index, dpf_material_id in enumerate(element_info.dpf_material_ids):
            tensile_strain_limit_1 = property_dict[dpf_material_id][material_property]
            selected_indices = get_selected_indices(element_info, layers=[layer_index])
            # Tensile max strain criteria in 1 direction
            layer_strain_values = strain_data[selected_indices][:, component]
            if tensile_strain_limit_1 > 0:
                layer_max = np.max(layer_strain_values)
                element_max = max(element_max, layer_max / tensile_strain_limit_1)

        # add to output field
        local_result_field.append([element_max], element_id)


composite_model.get_mesh().plot(result_field)

Static Scene

Interactive Scene