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Bath plate analysis

This example uses PyAEDT to set up the TEAM 3 bath plate problem and solve it using the Maxwell 3D eddy current solver.

For more information on this problem, see this paper.

Keywords: Maxwell 3D, TEAM 3 bath plate

Prerequisites

Perform imports

import os
import tempfile
import time

import ansys.aedt.core

Define constants

Constants help ensure consistency and avoid repetition throughout the example.

AEDT_VERSION = "2025.2"
NUM_CORES = 4
NG_MODE = False  # Open AEDT UI when it is launched.

Create temporary directory

Create a temporary working directory. The name of the working folder is stored in temp_folder.name.

Note: The final cell in the notebook cleans up the temporary folder. If you want to retrieve the AEDT project and data, do so before executing the final cell in the notebook.

temp_folder = tempfile.TemporaryDirectory(suffix=".ansys")

Launch Maxwell 3D

Create an instance of the Maxwell3d class named m3d by providing the project and design names, the solver, and the version.

m3d = ansys.aedt.core.Maxwell3d(
    project=os.path.join(temp_folder.name, "COMPUMAG.aedt"),
    design="TEAM_3_Bath_Plate",
    solution_type="EddyCurrent",
    version=AEDT_VERSION,
    non_graphical=NG_MODE,
    new_desktop=True,
)
uom = m3d.modeler.model_units = "mm"

PyAEDT INFO: Python version 3.10.11 (tags/v3.10.11:7d4cc5a, Apr  5 2023, 00:38:17) [MSC v.1929 64 bit (AMD64)].
PyAEDT INFO: PyAEDT version 0.24.dev0.
PyAEDT INFO: Initializing new Desktop session.
PyAEDT INFO: Log on console is enabled.
PyAEDT INFO: Log on file C:\Users\ansys\AppData\Local\Temp\pyaedt_ansys_fd0a4d20-2ab3-484c-bc98-c12d6b4db7ee.log is enabled.
PyAEDT INFO: Log on AEDT is disabled.
PyAEDT INFO: Starting new AEDT gRPC session.
PyAEDT INFO: AEDT installation Path C:\Program Files\ANSYS Inc\v252\AnsysEM
PyAEDT INFO: Client application successfully started.
PyAEDT INFO: New AEDT gRPC session session started on port 50051.
PyAEDT INFO: 2025.2 version started with process ID 9352.
PyAEDT WARNING: Service Pack is not detected. PyAEDT is currently connecting in Insecure Mode.
PyAEDT WARNING: Please download and install latest Service Pack to use connect to AEDT in Secure Mode.
PyAEDT INFO: Debug logger is disabled. PyAEDT methods will not be logged.
PyAEDT INFO: Project COMPUMAG has been created.
PyAEDT INFO: Added design 'TEAM_3_Bath_Plate' of type Maxwell 3D.
PyAEDT INFO: Aedt Objects correctly read
PyAEDT INFO: Modeler class has been initialized! Elapsed time: 0m 1sec

Add variable

Add a design variable named Coil_Position to use later to adjust the position of the coil.

Coil_Position = -20
m3d["Coil_Position"] = str(Coil_Position) + m3d.modeler.model_units

Add material

Add a material named team3_aluminium for the ladder plate.

mat = m3d.materials.add_material(name="team3_aluminium")
mat.conductivity = 32780000

PyAEDT INFO: Materials class has been initialized! Elapsed time: 0m 0sec
PyAEDT INFO: Adding new material to the Project Library: team3_aluminium
PyAEDT INFO: Material has been added in Desktop.

Draw background region

Draw a background region that uses the default properties for an air region.

m3d.modeler.create_air_region(
    x_pos=100, y_pos=100, z_pos=100, x_neg=100, y_neg=100, z_neg=100
)

Region

Draw ladder plate and assign material

Draw a ladder plate and assign it the newly created material team3_aluminium.

m3d.modeler.create_box(
    origin=[-30, -55, 0],
    sizes=[60, 110, -6.35],
    name="LadderPlate",
    material="team3_aluminium",
)
m3d.modeler.create_box(origin=[-20, -35, 0], sizes=[40, 30, -6.35], name="CutoutTool1")
m3d.modeler.create_box(origin=[-20, 5, 0], sizes=[40, 30, -6.35], name="CutoutTool2")
m3d.modeler.subtract(
    blank_list="LadderPlate",
    tool_list=["CutoutTool1", "CutoutTool2"],
    keep_originals=False,
)

PyAEDT INFO: Parsing design objects. This operation can take time
PyAEDT INFO: Refreshing bodies from Object Info
PyAEDT INFO: Bodies Info Refreshed Elapsed time: 0m 0sec
PyAEDT INFO: 3D Modeler objects parsed. Elapsed time: 0m 0sec

True

Add mesh refinement to ladder plate

Note: You can uncomment the following code.

m3d.mesh.assign_length_mesh( assignment=”LadderPlate”, maximum_length=3, maximum_elements=None, name=”Ladder_Mesh”, )

Draw search coil and assign excitation

Draw a search coil and assign it a stranded current excitation. The stranded type forces the current density to be constant in the coil.

m3d.modeler.create_cylinder(
    orientation="Z",
    origin=[0, "Coil_Position", 15],
    radius=40,
    height=20,
    name="SearchCoil",
    material="copper",
)
m3d.modeler.create_cylinder(
    orientation="Z",
    origin=[0, "Coil_Position", 15],
    radius=20,
    height=20,
    name="Bore",
    material="copper",
)
m3d.modeler.subtract(blank_list="SearchCoil", tool_list="Bore", keep_originals=False)
m3d.modeler.section(assignment="SearchCoil", plane="YZ")
m3d.modeler.separate_bodies(assignment="SearchCoil_Section1")
m3d.modeler.delete(assignment="SearchCoil_Section1_Separate1")
m3d.assign_current(
    assignment=["SearchCoil_Section1"],
    amplitude=1260,
    solid=False,
    name="SearchCoil_Excitation",
)

PyAEDT INFO: Parsing design objects. This operation can take time
PyAEDT INFO: Refreshing bodies from Object Info
PyAEDT INFO: Bodies Info Refreshed Elapsed time: 0m 0sec
PyAEDT INFO: 3D Modeler objects parsed. Elapsed time: 0m 0sec
PyAEDT INFO: Parsing design objects. This operation can take time
PyAEDT INFO: Refreshing bodies from Object Info
PyAEDT INFO: Bodies Info Refreshed Elapsed time: 0m 0sec
PyAEDT INFO: 3D Modeler objects parsed. Elapsed time: 0m 0sec
PyAEDT INFO: Deleted 1 Objects: SearchCoil_Section1_Separate1.
PyAEDT INFO: Boundary Current SearchCoil_Excitation has been created.

SearchCoil_Excitation

Draw a line for plotting \(B_z\)

Draw a line for plotting Bz later. Bz is the Z component of the flux density. The following code also adds a small diameter cylinder to refine the mesh locally around the line.

line_points = [["0mm", "-55mm", "0.5mm"], ["0mm", "55mm", "0.5mm"]]
m3d.modeler.create_polyline(points=line_points, name="Line_AB")
poly = m3d.modeler.create_polyline(points=line_points, name="Line_AB_MeshRefinement")
poly.set_crosssection_properties(section="Circle", width="0.5mm")

True

Add Maxwell 3D setup

Add a Maxwell 3D setup with frequency points at 50 Hz and 200 Hz.

setup = m3d.create_setup(name="Setup1")
setup.props["Frequency"] = "200Hz"
setup.props["HasSweepSetup"] = True
setup.props["MaximumPasses"] = 1
setup.add_eddy_current_sweep(
    sweep_type="LinearStep", start_frequency=50, stop_frequency=200, step_size=150, clear=True
)

PyAEDT INFO: Parsing C:\Users\ansys\AppData\Local\Temp\tmp8g6e2zoj.ansys\COMPUMAG.aedt.
PyAEDT INFO: File C:\Users\ansys\AppData\Local\Temp\tmp8g6e2zoj.ansys\COMPUMAG.aedt correctly loaded. Elapsed time: 0m 0sec
PyAEDT INFO: aedt file load time 0.014597892761230469

Setup1 : Setup1

Adjust eddy effects

Adjust eddy effects for the ladder plate and the search coil. The setting for eddy effect is ignored for the stranded conductor type used in the search coil.

m3d.eddy_effects_on(
    assignment=["LadderPlate"],
    enable_eddy_effects=True,
    enable_displacement_current=True,
)
m3d.eddy_effects_on(
    assignment=["SearchCoil"],
    enable_eddy_effects=False,
    enable_displacement_current=True,
)

True

Add linear parametric sweep

Add a linear parametric sweep for the two coil positions.

sweep_name = "CoilSweep"
param = m3d.parametrics.add(
    variable="Coil_Position",
    start_point=-20,
    end_point=0,
    step=20,
    variation_type="LinearStep",
    name=sweep_name,
)
param["SaveFields"] = True
param["CopyMesh"] = False
param["SolveWithCopiedMeshOnly"] = True

Solve parametric sweep

Solve the parametric sweep directly so that results of all variations are available.

m3d.save_project()
param.analyze(cores=NUM_CORES)

PyAEDT INFO: Project COMPUMAG Saved correctly
PyAEDT INFO: Project COMPUMAG Saved correctly
PyAEDT INFO: Key Desktop/ActiveDSOConfigurations/Maxwell 3D correctly changed.
PyAEDT INFO: Solving Optimetrics
PyAEDT INFO: Design setup CoilSweep solved correctly in 0.0h 1.0m 49.0s
PyAEDT INFO: Key Desktop/ActiveDSOConfigurations/Maxwell 3D correctly changed.

True

Postprocess

Create expression for Bz

Create an expression for Bz using PyAEDT advanced fields calculator.

bz = {
    "name": "Bz",
    "description": "Z component of B",
    "design_type": ["Maxwell 3D"],
    "fields_type": ["Fields"],
    "primary_sweep": "Distance",
    "assignment": "",
    "assignment_type": ["Line"],
    "operations": [
        "NameOfExpression('<Bx,By,Bz>')",
        "Operation('ScalarZ')",
        "Scalar_Constant(1000)",
        "Operation('*')",
        "Operation('Smooth')",
    ],
    "report": ["Field_3D"],
}
m3d.post.fields_calculator.add_expression(bz, None)

PyAEDT INFO: Parsing C:\Users\ansys\AppData\Local\Temp\tmp8g6e2zoj.ansys\COMPUMAG.aedt.
PyAEDT INFO: File C:\Users\ansys\AppData\Local\Temp\tmp8g6e2zoj.ansys\COMPUMAG.aedt correctly loaded. Elapsed time: 0m 0sec
PyAEDT INFO: aedt file load time 0.030411958694458008
PyAEDT INFO: PostProcessor class has been initialized! Elapsed time: 0m 0sec
PyAEDT INFO: PostProcessor class has been initialized! Elapsed time: 0m 0sec
PyAEDT INFO: Post class has been initialized! Elapsed time: 0m 0sec

'Bz'

Plot \(|B_z|\) as a function of frequency

Plot \(|B_z|\) as a function of frequency for both coil positions.

variations = {
    "Distance": ["All"],
    "Freq": ["All"],
    "Phase": ["0deg"],
    "Coil_Position": ["All"],
}

m3d.post.create_report(
    expressions="mag(Bz)",
    variations=variations,
    primary_sweep_variable="Distance",
    report_category="Fields",
    context="Line_AB",
    plot_name="mag(Bz) Along 'Line_AB' Coil",
)

mag(Bz) Along 'Line_AB' Coil

Get simulation results from a solved setup

Get simulation results from a solved setup as a SolutionData object.

solutions = m3d.post.get_solution_data(
    expressions="mag(Bz)",
    report_category="Fields",
    context="Line_AB",
    variations=variations,
    primary_sweep_variable="Distance",
)

PyAEDT INFO: Solution Data Correctly Loaded.
Time to initialize solution data:0.02019810676574707
Time to initialize solution data:0.03476858139038086

Set up sweep value and plot solution

solutions.active_variation["Coil_Position"] = -0.02
solutions.plot()

PyAEDT ERROR: **************************************************************
PyAEDT ERROR:   File "C:\actions-runner\_work\_tool\Python\3.10.11\x64\lib\runpy.py", line 196, in _run_module_as_main
PyAEDT ERROR:     return _run_code(code, main_globals, None,
PyAEDT ERROR:   File "C:\actions-runner\_work\_tool\Python\3.10.11\x64\lib\runpy.py", line 86, in _run_code
PyAEDT ERROR:     exec(code, run_globals)
PyAEDT ERROR:   File "C:\actions-runner\_work\_tool\Python\3.10.11\x64\lib\asyncio\base_events.py", line 603, in run_forever
PyAEDT ERROR:     self._run_once()
PyAEDT ERROR:   File "C:\actions-runner\_work\_tool\Python\3.10.11\x64\lib\asyncio\base_events.py", line 1909, in _run_once
PyAEDT ERROR:     handle._run()
PyAEDT ERROR:   File "C:\actions-runner\_work\_tool\Python\3.10.11\x64\lib\asyncio\events.py", line 80, in _run
PyAEDT ERROR:     self._context.run(self._callback, *self._args)
PyAEDT ERROR:   File "C:\Users\ansys\AppData\Local\Temp\ipykernel_17596\3006651278.py", line 2, in <module>
PyAEDT ERROR:     solutions.plot()
PyAEDT ERROR:   File "C:\actions-runner\_work\pyaedt-examples\pyaedt-examples\.venv\lib\site-packages\ansys\aedt\core\visualization\post\solution_data.py", line 941, in plot
PyAEDT ERROR:     report_plotter = self.get_report_plotter(curves=curves, formula=formula, to_radians=to_radians, props=props)
PyAEDT ERROR:   File "C:\actions-runner\_work\pyaedt-examples\pyaedt-examples\.venv\lib\site-packages\ansys\aedt\core\visualization\post\solution_data.py", line 873, in get_report_plotter
PyAEDT ERROR:     new.add_trace([sw, self._get_data_formula(curve, formula)], name=name, properties=props)
PyAEDT ERROR:   File "C:\actions-runner\_work\pyaedt-examples\pyaedt-examples\.venv\lib\site-packages\ansys\aedt\core\visualization\plot\matplotlib.py", line 916, in add_trace
PyAEDT ERROR:     nt.cartesian_data = plot_data
PyAEDT ERROR:   File "C:\actions-runner\_work\pyaedt-examples\pyaedt-examples\.venv\lib\site-packages\ansys\aedt\core\visualization\plot\matplotlib.py", line 348, in cartesian_data
PyAEDT ERROR:     self._cartesian_data.append(np.zeros(len(val[-1])))
PyAEDT ERROR: Object of type 'nonetype' has no len() on add_trace
PyAEDT ERROR: Method arguments:
PyAEDT ERROR:     plot_data = [array([  0.  ,   0.11,   0.22, ..., 109.78, 109.89, 110.  ], shape=(1001,)), None]
PyAEDT ERROR:     properties = {'x_label': '', 'y_label': ''}
PyAEDT ERROR:     name = (mag(Bz))_Phase=0.0,Freq=50.0
PyAEDT ERROR: **************************************************************

False

Change sweep value and plot solution

Change the sweep value and plot the solution again. Uncomment to show plots.

solutions.active_variation["Coil_Position"] = 0
# solutions.plot()

Plot induced current density on surface of ladder plate

Plot the induced current density, "Mag_J", on the surface of the ladder plate.

ladder_plate = m3d.modeler.objects_by_name["LadderPlate"]
intrinsics = {"Freq": "50Hz", "Phase": "0deg"}
m3d.post.create_fieldplot_surface(
    assignment=ladder_plate.faces,
    quantity="Mag_J",
    intrinsics=intrinsics,
    plot_name="Mag_J",
)

PyAEDT INFO: Active Design set to TEAM_3_Bath_Plate

Class: ansys.aedt.core.visualization.post.field_data.FieldPlot

Finish

Save the project

m3d.save_project()
m3d.release_desktop()
# Wait 3 seconds to allow AEDT to shut down before cleaning the temporary directory.
time.sleep(3)

PyAEDT INFO: Project COMPUMAG Saved correctly
PyAEDT INFO: Desktop has been released and closed.

Clean up

All project files are saved in the folder temp_folder.name. If you’ve run this example as a Jupyter notebook, you can retrieve those project files. The following cell removes all temporary files, including the project folder.

temp_folder.cleanup()

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