Plot stress data on surface coating elements

Pernelle Marone-Hitz

How can I use DPF to retrieve stress data on surface coating elements and plot those results in Mechanical ?

Pernelle Marone-Hitz

First, it is important to understand that there are two options to create surface coating elements in Mechanical.

• Option 1: Define a surface coating object at the geometry level
  

• Option 2: Add a Mesh Edit / Pull / Surface coating object
  
  Once generated, this will create a new surface body in the geometry:
  

To post-process the results through the Mechanical UI, the procedure will be different based on how these surface coating elements were generated:

• Option 1: Add a result and use the geometry scoping
  

• Option 2: Add a result but this time set scoping method to "Surface coating"
  

As the surface coating objects are created differently, the way to retrieve the result data through DPF will slightly differ:

• Option 1: we can use GetObjectsByType() method to grab the surface coating object
• Option 2: we can use GetObjectsByName() method to grab the body by its name, or any similar option, but surface coating bodies created through this option are not recognized as surface coatings but as standard bodies.

The rest of the method is very similar:

• use DPF to retrieve stress results
• use SolverData API to restrict the scoping to surface coating elements
• create a mesh for the surface coating elements only
• plot the results with the restricted scoping on the restricted mesh.

Pernelle Marone-Hitz

The main Python Result function define_dpf_workflow() will slighlty differ for the two options:

• Option 1: surface coating created at geometry level

def define_dpf_workflow(analysis):
    # import DPF and define data sources
    import mech_dpf
    import Ans.DataProcessing as dpf
    mech_dpf.setExtAPI(ExtAPI)
    dataSource = dpf.DataSources(analysis.ResultFileName)
    model = dpf.Model(dataSource)

    # retrieve entire mesh
    whole_mesh = model.Mesh

    # retrieve nodal Von Mises stress
    seqv = dpf.operators.result.stress_von_mises()
    seqv.inputs.data_sources.Connect(dataSource)
    seqv.inputs.requested_location.Connect(dpf.locations.nodal)

    # identify surface coating elements
    surface_coating = ExtAPI.DataModel.GetObjectsByType(Ansys.ACT.Automation.Mechanical.SurfaceCoating)[0]
    solver_data = analysis.Solution.SolverData
    coating_data = solver_data.GetObjectData(surface_coating)
    matid_sc_1 = coating_data.MaterialId.ToString()
    surface_coating_elements = solver_data.ElementIdsByMaterialId(matid_sc_1)

    # define mesh scoping for surface coating elements
    mesh_scoping=dpf.Scoping()
    mesh_scoping.Location = dpf.locations.elemental
    mesh_scoping.Ids=surface_coating_elements

    # restrict stress results to surface coating elements
    seqv.inputs.mesh_scoping.Connect(mesh_scoping)

    # get mesh for surface coating elements only
    mesh_from_scoping = dpf.operators.mesh.from_scoping()
    mesh_from_scoping.inputs.scoping.Connect(mesh_scoping)
    mesh_from_scoping.inputs.mesh.Connect(whole_mesh)
    my_mesh = mesh_from_scoping.outputs.getmesh()

    dpf_workflow = dpf.Workflow()
    dpf_workflow.Add(seqv)

    # plot on restricted mesh
    dpf_workflow.SetOutputMesh(my_mesh)
    dpf_workflow.SetOutputContour(seqv)
    dpf_workflow.Record('wf_id', False)
    this.WorkflowId = dpf_workflow.GetRecordedId()

Pernelle Marone-Hitz

• Option 2: surface coating created through mesh edit / pull

def define_dpf_workflow(analysis):
    # import DPF and define data sources
    import mech_dpf
    import Ans.DataProcessing as dpf
    mech_dpf.setExtAPI(ExtAPI)
    dataSource = dpf.DataSources(analysis.ResultFileName)
    model = dpf.Model(dataSource)

    # retrieve entire mesh
    whole_mesh = model.Mesh

    # retrieve nodal Von Mises stress
    seqv = dpf.operators.result.stress_von_mises()
    seqv.inputs.data_sources.Connect(dataSource)
    seqv.inputs.requested_location.Connect(dpf.locations.nodal)

    # identify surface coating elements

    surface_coating = ExtAPI.DataModel.GetObjectsByName('Surface body from mesh edit pull')[0]
    solver_data = analysis.Solution.SolverData
    coating_data = solver_data.GetObjectData(surface_coating)
    matid_sc_1 = coating_data.MaterialIds[0].ToString()
    surface_coating_elements = solver_data.ElementIdsByMaterialId(matid_sc_1)

    # define mesh scoping for surface coating elements
    mesh_scoping=dpf.Scoping()
    mesh_scoping.Location = dpf.locations.elemental
    mesh_scoping.Ids=surface_coating_elements

    # restrict stress results to surface coating elements
    seqv.inputs.mesh_scoping.Connect(mesh_scoping)

    # get mesh for surface coating elements only
    mesh_from_scoping = dpf.operators.mesh.from_scoping()
    mesh_from_scoping.inputs.scoping.Connect(mesh_scoping)
    mesh_from_scoping.inputs.mesh.Connect(whole_mesh)
    my_mesh = mesh_from_scoping.outputs.getmesh()

    dpf_workflow = dpf.Workflow()
    dpf_workflow.Add(seqv)

    # plot on restricted mesh
    dpf_workflow.SetOutputMesh(my_mesh)
    dpf_workflow.SetOutputContour(seqv)
    dpf_workflow.Record('wf_id', False)
    this.WorkflowId = dpf_workflow.GetRecordedId()

Pernelle Marone-Hitz

In both cases we are able to get the same results as in Mechanical:

• Option 1:
  

• Option 2: