Note
Go to the end to download the full example code.
PyMechanical solid workflow#
This example shows how to set up a simple solid model with PyACP and PyMechanical:
The geometry is imported into Mechanical and meshed.
The mesh is exported to ACP.
A simple lay-up and solid model is defined in ACP.
The solid model is exported, to a CDB file and a composite definition file.
In a separate Mechanical instance, the solid model is imported.
Materials and plies are imported.
Boundary conditions are set.
The model is solved.
The results are post-processed in PyDPF Composites.
Warning
The PyACP / PyMechanical integration is still experimental. Refer to the limitations section for more information.
Import modules and start the Ansys products#
Import the standard library and third-party dependencies.
from concurrent.futures import ThreadPoolExecutor
import pathlib
import tempfile
import textwrap
Import PyACP, PyMechanical, and PyDPF Composites.
# isort: off
import ansys.acp.core as pyacp
import ansys.dpf.composites as pydpf_composites
import ansys.mechanical.core as pymechanical
Start the ACP, Mechanical, and DPF servers. We use a ThreadPoolExecutor
to start them in parallel.
with ThreadPoolExecutor() as executor:
futures = [
executor.submit(pymechanical.launch_mechanical, batch=True),
executor.submit(pymechanical.launch_mechanical, batch=True),
executor.submit(pyacp.launch_acp),
executor.submit(pydpf_composites.server_helpers.connect_to_or_start_server),
]
mechanical_shell_geometry, mechanical_solid_model, acp, dpf = (fut.result() for fut in futures)
Get example input files#
Create a temporary working directory, and download the example input files to this directory.
working_dir = tempfile.TemporaryDirectory()
working_dir_path = pathlib.Path(working_dir.name)
input_geometry = pyacp.extras.example_helpers.get_example_file(
pyacp.extras.example_helpers.ExampleKeys.CLASS40_AGDB, working_dir_path
)
Generate the mesh in PyMechanical#
Load the geometry into Mechanical, generate the mesh, and export it to the appropriate transfer format for ACP.
mesh_path = working_dir_path / "mesh.h5"
mechanical_shell_geometry.run_python_script(
# This script runs in the Mechanical Python environment, which uses IronPython 2.7.
textwrap.dedent(
f"""\
geometry_import = Model.GeometryImportGroup.AddGeometryImport()
import_format = Ansys.Mechanical.DataModel.Enums.GeometryImportPreference.Format.Automatic
import_preferences = Ansys.ACT.Mechanical.Utilities.GeometryImportPreferences()
import_preferences.ProcessNamedSelections = True
import_preferences.ProcessCoordinateSystems = True
geometry_file = {str(input_geometry)!r}
geometry_import.Import(
geometry_file,
import_format,
import_preferences
)
for body in Model.Geometry.GetChildren(
Ansys.Mechanical.DataModel.Enums.DataModelObjectCategory.Body, True
):
body.Thickness = Quantity(1e-6, "m")
hull = Model.AddNamedSelection()
hull.Name = "hull"
hull.ScopingMethod = GeometryDefineByType.Worksheet
# Add all faces with Z location < 0.9 m
hull.GenerationCriteria.Add(None)
hull.GenerationCriteria[0].EntityType = SelectionType.GeoFace
hull.GenerationCriteria[0].Operator = SelectionOperatorType.LessThan
hull.GenerationCriteria[0].Criterion = SelectionCriterionType.LocationZ
hull.GenerationCriteria[0].Value = Quantity('0.9 [m]')
# Remove keeltower
hull.GenerationCriteria.Add(None)
hull.GenerationCriteria[1].Action = SelectionActionType.Remove
hull.GenerationCriteria[1].Criterion = SelectionCriterionType.LocationX
hull.GenerationCriteria[1].Operator = SelectionOperatorType.RangeInclude
hull.GenerationCriteria[1].LowerBound = Quantity('-6.7 [m]')
hull.GenerationCriteria[1].UpperBound = Quantity('-5.9 [m]')
# Add back keeltower bottom
hull.GenerationCriteria.Add(None)
hull.GenerationCriteria[2].Criterion = SelectionCriterionType.LocationZ
hull.GenerationCriteria[2].Operator = SelectionOperatorType.LessThan
hull.GenerationCriteria[2].Value = Quantity('-0.25 [m]')
# Remove bulkhead
hull.GenerationCriteria.Add(None)
hull.GenerationCriteria[3].Action = SelectionActionType.Remove
hull.GenerationCriteria[3].Criterion = SelectionCriterionType.LocationX
hull.GenerationCriteria[3].Operator = SelectionOperatorType.RangeInclude
hull.GenerationCriteria[3].LowerBound = Quantity('-5.7 [m]')
hull.GenerationCriteria[3].UpperBound = Quantity('-5.6 [m]')
hull.Generate()
Model.Mesh.GenerateMesh()
"""
)
)
pyacp.mechanical_integration_helpers.export_mesh_for_acp(
mechanical=mechanical_shell_geometry, path=mesh_path
)
Set up the ACP model#
Setup basic ACP lay-up based on the mesh in mesh_path, and export the following
files to output_path:
Materials XML file
Composite definitions HDF5 file
Solid model composite definitions HDF5 file
Solid model CDB file
matml_file = "materials.xml"
solid_model_cdb_file = "SolidModel.cdb"
solid_model_composite_definitions_h5 = "SolidModel.h5"
model = acp.import_model(path=mesh_path, format="ansys:h5")
mat = model.create_material(name="mat")
mat.ply_type = "regular"
mat.engineering_constants.E1 = 1e12
mat.engineering_constants.E2 = 1e11
mat.engineering_constants.E3 = 1e11
mat.engineering_constants.G12 = 1e10
mat.engineering_constants.G23 = 1e10
mat.engineering_constants.G31 = 1e10
mat.engineering_constants.nu12 = 0.3
mat.engineering_constants.nu13 = 0.3
mat.engineering_constants.nu23 = 0.3
mat.strain_limits = pyacp.material_property_sets.ConstantStrainLimits.from_orthotropic_constants(
eXc=-0.01,
eYc=-0.01,
eZc=-0.01,
eXt=0.01,
eYt=0.01,
eZt=0.01,
eSxy=0.01,
eSyz=0.01,
eSxz=0.01,
)
corecell_81kg_5mm = model.create_fabric(name="Corecell 81kg", thickness=0.005, material=mat)
ros = model.create_rosette(name="ros", origin=(0, 0, 0))
oss = model.create_oriented_selection_set(
name="oss",
orientation_point=(-0, 0, 0),
orientation_direction=(0.0, 1, 0.0),
element_sets=[model.element_sets["All_Elements"]],
rosettes=[ros],
)
mg = model.create_modeling_group(name="group")
mg.create_modeling_ply(
name="ply",
ply_material=corecell_81kg_5mm,
oriented_selection_sets=[oss],
ply_angle=45,
number_of_layers=1,
global_ply_nr=0, # add at the end
)
mg.create_modeling_ply(
name="ply2",
ply_material=corecell_81kg_5mm,
oriented_selection_sets=[oss],
ply_angle=0,
number_of_layers=2,
global_ply_nr=0, # add at the end
)
solid_model = model.create_solid_model(
element_sets=[model.element_sets["hull"]],
)
Update and Save the ACP model#
model.update()
model.export_materials(working_dir_path / matml_file)
solid_model.export(working_dir_path / solid_model_cdb_file, format="ansys:cdb")
solid_model.export(working_dir_path / solid_model_composite_definitions_h5, format="ansys:h5")
Import mesh, materials and plies into Mechanical#
Import geometry, mesh, and named selections into Mechanical
pyacp.mechanical_integration_helpers.import_acp_mesh_from_cdb(
mechanical=mechanical_solid_model, cdb_path=working_dir_path / solid_model_cdb_file
)
Import materials into Mechanical
mechanical_solid_model.run_python_script(
f"Model.Materials.Import({str(working_dir_path / matml_file)!r})"
)
Import plies into Mechanical
pyacp.mechanical_integration_helpers.import_acp_composite_definitions(
mechanical=mechanical_solid_model, path=working_dir_path / solid_model_composite_definitions_h5
)
Set boundary condition and solve#
Set boundary condition and solve
mechanical_solid_model.run_python_script(
textwrap.dedent(
"""\
analysis = Model.AddStaticStructuralAnalysis()
front_face = Model.AddNamedSelection()
front_face.Name = "front_face"
front_face.ScopingMethod = GeometryDefineByType.Worksheet
front_face.GenerationCriteria.Add(None)
front_face.GenerationCriteria[0].EntityType = SelectionType.GeoFace
front_face.GenerationCriteria[0].Criterion = SelectionCriterionType.LocationX
front_face.GenerationCriteria[0].Operator = SelectionOperatorType.Largest
front_face.Generate()
back_face = Model.AddNamedSelection()
back_face.Name = "back_face"
back_face.ScopingMethod = GeometryDefineByType.Worksheet
back_face.GenerationCriteria.Add(None)
back_face.GenerationCriteria[0].EntityType = SelectionType.GeoFace
back_face.GenerationCriteria[0].Criterion = SelectionCriterionType.LocationX
back_face.GenerationCriteria[0].Operator = SelectionOperatorType.Smallest
back_face.Generate()
fixed_support = analysis.AddFixedSupport()
fixed_support.Location = back_face
force = analysis.AddForce()
force.DefineBy = LoadDefineBy.Components
force.XComponent.Output.SetDiscreteValue(0, Quantity(1e5, "N"))
force.Location = front_face
analysis.Solve(True)
"""
)
)
rst_file = [
filename for filename in mechanical_solid_model.list_files() if filename.endswith(".rst")
][0]
matml_out = [
filename for filename in mechanical_solid_model.list_files() if filename.endswith("MatML.xml")
][0]
Postprocess results#
Evaluate the failure criteria using the PyDPF Composites.
max_strain = pydpf_composites.failure_criteria.MaxStrainCriterion()
cfc = pydpf_composites.failure_criteria.CombinedFailureCriterion(
name="Combined Failure Criterion",
failure_criteria=[max_strain],
)
composite_model = pydpf_composites.composite_model.CompositeModel(
composite_files=pydpf_composites.data_sources.ContinuousFiberCompositesFiles(
rst=rst_file,
composite={
"solid": pydpf_composites.data_sources.CompositeDefinitionFiles(
definition=working_dir_path / solid_model_composite_definitions_h5
),
},
engineering_data=working_dir_path / matml_out,
),
server=dpf,
)
# Evaluate the failure criteria
output_all_elements = composite_model.evaluate_failure_criteria(cfc)
# Query and plot the results
irf_field = output_all_elements.get_field(
{"failure_label": pydpf_composites.constants.FailureOutput.FAILURE_VALUE}
)
irf_field.plot()