.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "examples\06-Multiphysics\MRI.py"
.. LINE NUMBERS ARE GIVEN BELOW.
.. only:: html
.. note::
:class: sphx-glr-download-link-note
:ref:`Go to the end <sphx_glr_download_examples_06-Multiphysics_MRI.py>`
to download the full example code.
.. rst-class:: sphx-glr-example-title
.. _sphx_glr_examples_06-Multiphysics_MRI.py:
Multiphysics: HFSS-Mechanical MRI analysis
---------------------------------------------------
The goal of this workshop is to use a coil tuned to 63.8 MHz to determine the temperature
rise in a gel phantom near an implant given a background SAR of 1 W/kg.
Steps to follow
Step 1: Simulate coil loaded by empty phantom:
Scale input to coil ports to produce desired background SAR of 1 W/kg at location that will later contain the implant.
Step 2: Simulate coil loaded by phantom containing implant in proper location:
View SAR in tissue surrounding implant.
Step 3: Thermal simulation:
Link HFSS to transient thermal solver to find temperature rise in tissue near implant vs. time.
.. GENERATED FROM PYTHON SOURCE LINES 17-20
Perform required imports
~~~~~~~~~~~~~~~~~~~~~~~~
Perform required imports.
.. GENERATED FROM PYTHON SOURCE LINES 20-24
.. code-block:: Python
import os.path
from pyaedt import Hfss, Mechanical, Icepak, downloads
.. GENERATED FROM PYTHON SOURCE LINES 25-28
Set AEDT version
~~~~~~~~~~~~~~~~
Set AEDT version.
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.. code-block:: Python
aedt_version = "2024.1"
.. GENERATED FROM PYTHON SOURCE LINES 32-36
Set non-graphical mode
~~~~~~~~~~~~~~~~~~~~~~
Set non-graphical mode. `
You can set ``non_graphical`` either to ``True`` or ``False``.
.. GENERATED FROM PYTHON SOURCE LINES 36-39
.. code-block:: Python
non_graphical = False
.. GENERATED FROM PYTHON SOURCE LINES 40-48
Project load
~~~~~~~~~~~~
Open the ANSYS Electronics Desktop 2018.2
Open project background_SAR.aedt
Project contains phantom and airbox
Phantom consists of two objects: phantom and implant_box
Separate objects are used to selectively assign mesh operations
Material properties defined in this project already contain #electrical and thermal properties.
.. GENERATED FROM PYTHON SOURCE LINES 48-53
.. code-block:: Python
project_path = downloads.download_file(directory="mri")
hfss = Hfss(os.path.join(project_path, "background_SAR.aedt"), specified_version=aedt_version, non_graphical=non_graphical,
new_desktop_session=True)
.. rst-class:: sphx-glr-script-out
.. code-block:: none
C:\actions-runner\_work\_tool\Python\3.10.9\x64\lib\subprocess.py:1072: ResourceWarning: subprocess 12340 is still running
_warn("subprocess %s is still running" % self.pid,
C:\actions-runner\_work\pyaedt\pyaedt\.venv\lib\site-packages\pyaedt\generic\settings.py:383: ResourceWarning: unclosed file <_io.TextIOWrapper name='D:\\Temp\\pyaedt_ansys.log' mode='a' encoding='cp1252'>
self._logger = val
.. GENERATED FROM PYTHON SOURCE LINES 54-61
Insert 3D component
~~~~~~~~~~~~~~~~~~~
The MRI Coil is saved as a separate 3D Component
‒ 3D Components store geometry (including parameters),
material properties, boundary conditions, mesh assignments,
and excitations
‒ 3D Components make it easy to reuse and share parts of a simulation
.. GENERATED FROM PYTHON SOURCE LINES 61-64
.. code-block:: Python
hfss.modeler.insert_3d_component(os.path.join(project_path, "coil.a3dcomp"))
.. rst-class:: sphx-glr-script-out
.. code-block:: none
<pyaedt.modeler.cad.components_3d.UserDefinedComponent object at 0x00000226669DF430>
.. GENERATED FROM PYTHON SOURCE LINES 65-71
Expression Cache
~~~~~~~~~~~~~~~~~
On the expression cache tab, define additional convergence criteria for self impedance of the four coil
ports
‒ Set each of these convergence criteria to 2.5 ohm
For this demo number of passes is limited to 2 to reduce simulation time.
.. GENERATED FROM PYTHON SOURCE LINES 71-83
.. code-block:: Python
im_traces = hfss.get_traces_for_plot(get_mutual_terms=False, category="im(Z", first_element_filter="Coil1_p*")
hfss.setups[0].enable_expression_cache(
report_type="Modal Solution Data",
expressions=im_traces,
isconvergence=True,
isrelativeconvergence=False,
conv_criteria=2.5,
use_cache_for_freq=False)
hfss.setups[0].props["MaximumPasses"] = 2
.. GENERATED FROM PYTHON SOURCE LINES 84-91
Edit Sources
~~~~~~~~~~~~
The 3D Component of the MRI Coil contains all the ports,
but the sources for these ports are not yet defined.
Browse to and select sources.csv.
These sources were determined by tuning this coil at 63.8 MHz.
Notice the “*input_scale” multiplier to allow quick adjustment of the coil excitation power.
.. GENERATED FROM PYTHON SOURCE LINES 91-94
.. code-block:: Python
hfss.edit_sources_from_file(os.path.join(project_path, "sources.csv"))
.. rst-class:: sphx-glr-script-out
.. code-block:: none
True
.. GENERATED FROM PYTHON SOURCE LINES 95-98
Run Simulation
~~~~~~~~~~~~~~
Save and analyze the project.
.. GENERATED FROM PYTHON SOURCE LINES 98-102
.. code-block:: Python
hfss.save_project(os.path.join(project_path, "solved.aedt"))
hfss.analyze(cores=6)
.. rst-class:: sphx-glr-script-out
.. code-block:: none
True
.. GENERATED FROM PYTHON SOURCE LINES 103-108
Plot SAR on cut plane in phantom
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Ensure that the SAR averaging method is set to Gridless
Plot averagedSAR on GlobalYZ plane
Draw Point1 at origin of the implant coordinate system
.. GENERATED FROM PYTHON SOURCE LINES 108-118
.. code-block:: Python
hfss.sar_setup(-1, tissue_mass=1, material_density=1, average_sar_method=1)
hfss.post.create_fieldplot_cutplane(assignment="implant:YZ", quantity="Average_SAR", filter_objects=["implant_box"])
hfss.modeler.set_working_coordinate_system("implant")
hfss.modeler.create_point([0, 0, 0], name="Point1")
hfss.post.plot_field(quantity="Average_SAR", assignment="implant:YZ", plot_type="CutPlane", show=False,
show_legend=False, filter_objects=["implant_box"])
.. rst-class:: sphx-glr-script-out
.. code-block:: none
<pyaedt.generic.plot.ModelPlotter object at 0x000002265F6F34C0>
.. GENERATED FROM PYTHON SOURCE LINES 119-125
Adjust Input Power to MRI Coil
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The goal is to adjust the MRI coil’s input power, so that the averageSAR at Point1 is 1 W/kg
Note that SAR and input power are linearly related
To determine required input, calculate
input_scale = 1/AverageSAR at Point1
.. GENERATED FROM PYTHON SOURCE LINES 125-134
.. code-block:: Python
sol_data = hfss.post.get_solution_data(expressions="Average_SAR",
primary_sweep_variable="Freq",
context="Point1",
report_category="Fields")
sol_data.data_real()
hfss["input_scale"] = 1 / sol_data.data_real()[0]
.. GENERATED FROM PYTHON SOURCE LINES 135-141
Phantom with Implant
~~~~~~~~~~~~~~~~~~~~
Import implant geometry.
Subtract rod from implant_box.
Assign titanium to the imported object rod.
Analyze the project.
.. GENERATED FROM PYTHON SOURCE LINES 141-149
.. code-block:: Python
hfss.modeler.import_3d_cad(os.path.join(project_path, "implant_rod.sat"))
hfss.modeler["implant_box"].subtract("rod", keep_originals=True)
hfss.modeler["rod"].material_name = "titanium"
hfss.analyze(cores=6)
hfss.save_project()
.. rst-class:: sphx-glr-script-out
.. code-block:: none
True
.. GENERATED FROM PYTHON SOURCE LINES 150-154
Thermal Simulation
~~~~~~~~~~~~~~~~~~
Initialize a new Mechanical Transient Thermal analysis.
Mechanical Transient Thermal is available in AEDT from 2023 R2 as a Beta feature.
.. GENERATED FROM PYTHON SOURCE LINES 154-157
.. code-block:: Python
mech = Mechanical(solution_type="Transient Thermal", specified_version=aedt_version)
.. GENERATED FROM PYTHON SOURCE LINES 158-161
Copy geometries
~~~~~~~~~~~~~~~
Copy bodies from the HFSS project. 3D Component will not be copied.
.. GENERATED FROM PYTHON SOURCE LINES 161-164
.. code-block:: Python
mech.copy_solid_bodies_from(hfss)
.. rst-class:: sphx-glr-script-out
.. code-block:: none
True
.. GENERATED FROM PYTHON SOURCE LINES 165-169
Link sources to EM losses
~~~~~~~~~~~~~~~~~~~~~~~~~
Link sources to the EM losses.
Assign external convection.
.. GENERATED FROM PYTHON SOURCE LINES 169-175
.. code-block:: Python
exc = mech.assign_em_losses(design=hfss.design_name, setup=hfss.setups[0].name, sweep="LastAdaptive",
map_frequency=hfss.setups[0].props["Frequency"],
surface_objects=mech.get_all_conductors_names())
mech.assign_uniform_convection(mech.modeler["Region"].faces, convection_value=1)
.. rst-class:: sphx-glr-script-out
.. code-block:: none
<pyaedt.modules.Boundary.BoundaryObject object at 0x0000022668733220>
.. GENERATED FROM PYTHON SOURCE LINES 176-180
Create Setup
~~~~~~~~~~~~
Create a new setup and edit properties.
Simulation will be for 60 seconds.
.. GENERATED FROM PYTHON SOURCE LINES 180-193
.. code-block:: Python
setup = mech.create_setup()
# setup.add_mesh_link("backgroundSAR")
# mech.create_dataset1d_design("PowerMap", [0, 239, 240, 360], [1, 1, 0, 0])
# exc.props["LossMultiplier"] = "pwl(PowerMap,Time)"
mech.modeler.set_working_coordinate_system("implant")
mech.modeler.create_point([0, 0, 0], name="Point1")
setup.props["Stop Time"] = 60
setup.props["Time Step"] = "10s"
setup.props["SaveFieldsType"] = "Every N Steps"
setup.props["N Steps"] = "2"
.. GENERATED FROM PYTHON SOURCE LINES 194-197
Analyze Mechanical
~~~~~~~~~~~~~~~~~~
Analyze the project.
.. GENERATED FROM PYTHON SOURCE LINES 197-200
.. code-block:: Python
mech.analyze(cores=6)
.. rst-class:: sphx-glr-script-out
.. code-block:: none
True
.. GENERATED FROM PYTHON SOURCE LINES 201-205
Plot fields
~~~~~~~~~~~
Plot Temperature on cut plane.
Plot Temperature on point.
.. GENERATED FROM PYTHON SOURCE LINES 205-218
.. code-block:: Python
mech.post.create_fieldplot_cutplane("implant:YZ", "Temperature", filter_objects=["implant_box"])
mech.save_project()
data = mech.post.get_solution_data("Temperature", primary_sweep_variable="Time", context="Point1",
report_category="Fields")
#data.plot()
mech.post.plot_animated_field(quantity="Temperature", assignment="implant:YZ", plot_type="CutPlane",
intrinsics={"Time": "10s"}, variation_variable="Time",
variations=["10s", "20s", "30s", "40s", "50s", "60s"],
show=False, filter_objects=["implant_box"])
.. rst-class:: sphx-glr-script-out
.. code-block:: none
<pyaedt.generic.plot.ModelPlotter object at 0x000002264D689D50>
.. GENERATED FROM PYTHON SOURCE LINES 219-222
Thermal Simulation
~~~~~~~~~~~~~~~~~~
Initialize a new Icepak Transient Thermal analysis.
.. GENERATED FROM PYTHON SOURCE LINES 222-226
.. code-block:: Python
ipk = Icepak(solution_type="Transient", specified_version=aedt_version)
ipk.design_solutions.problem_type = "TemperatureOnly"
.. GENERATED FROM PYTHON SOURCE LINES 227-230
Copy geometries
~~~~~~~~~~~~~~~
Copy bodies from the HFSS project. 3D Component will not be copied.
.. GENERATED FROM PYTHON SOURCE LINES 230-234
.. code-block:: Python
ipk.modeler.delete("Region")
ipk.copy_solid_bodies_from(hfss)
.. rst-class:: sphx-glr-script-out
.. code-block:: none
True
.. GENERATED FROM PYTHON SOURCE LINES 235-239
Link sources to EM losses
~~~~~~~~~~~~~~~~~~~~~~~~~
Link sources to the EM losses.
Assign external convection.
.. GENERATED FROM PYTHON SOURCE LINES 239-244
.. code-block:: Python
exc = ipk.assign_em_losses(design=hfss.design_name, setup=hfss.setups[0].name, sweep="LastAdaptive",
map_frequency=hfss.setups[0].props["Frequency"],
surface_objects=ipk.get_all_conductors_names())
.. GENERATED FROM PYTHON SOURCE LINES 245-249
Create Setup
~~~~~~~~~~~~
Create a new setup and edit properties.
Simulation will be for 60 seconds.
.. GENERATED FROM PYTHON SOURCE LINES 249-257
.. code-block:: Python
setup = ipk.create_setup()
setup.props["Stop Time"] = 60
setup.props["N Steps"] = 2
setup.props["Time Step"] = 5
setup.props['Convergence Criteria - Energy'] = 1e-12
.. GENERATED FROM PYTHON SOURCE LINES 258-261
Mesh Region
~~~~~~~~~~~
Create a new mesh region and change accuracy level to 4.
.. GENERATED FROM PYTHON SOURCE LINES 261-270
.. code-block:: Python
bound = ipk.modeler["implant_box"].bounding_box
mesh_box = ipk.modeler.create_box(bound[:3], [bound[3] - bound[0], bound[4] - bound[1], bound[5] - bound[2]])
mesh_box.model = False
mesh_region = ipk.mesh.assign_mesh_region([mesh_box.name])
mesh_region.UserSpecifiedSettings = False
mesh_region.Level = 4
mesh_region.update()
.. rst-class:: sphx-glr-script-out
.. code-block:: none
True
.. GENERATED FROM PYTHON SOURCE LINES 271-274
Point Monitor
~~~~~~~~~~~~~
Create a new point monitor.
.. GENERATED FROM PYTHON SOURCE LINES 274-279
.. code-block:: Python
ipk.modeler.set_working_coordinate_system("implant")
ipk.monitor.assign_point_monitor([0, 0, 0], monitor_name="Point1")
ipk.assign_openings(ipk.modeler["Region"].top_face_z)
.. rst-class:: sphx-glr-script-out
.. code-block:: none
<pyaedt.modules.Boundary.BoundaryObject object at 0x000002264DDE35B0>
.. GENERATED FROM PYTHON SOURCE LINES 280-285
Analyze and plot fields
~~~~~~~~~~~~~~~~~~~~~~~
Analyze the project.
Plot temperature on cut plane.
Plot temperature on monitor point.
.. GENERATED FROM PYTHON SOURCE LINES 285-294
.. code-block:: Python
ipk.analyze(cores=4, tasks=4)
ipk.post.create_fieldplot_cutplane("implant:YZ", "Temperature", filter_objects=["implant_box"])
ipk.save_project()
data = ipk.post.get_solution_data("Point1.Temperature", primary_sweep_variable="Time", report_category="Monitor")
#data.plot()
ipk.release_desktop(True, True)
.. rst-class:: sphx-glr-script-out
.. code-block:: none
True
.. rst-class:: sphx-glr-timing
**Total running time of the script:** (20 minutes 30.782 seconds)
.. _sphx_glr_download_examples_06-Multiphysics_MRI.py:
.. only:: html
.. container:: sphx-glr-footer sphx-glr-footer-example
.. container:: sphx-glr-download sphx-glr-download-jupyter
:download:`Download Jupyter notebook: MRI.ipynb <MRI.ipynb>`
.. container:: sphx-glr-download sphx-glr-download-python
:download:`Download Python source code: MRI.py <MRI.py>`
.. only:: html
.. rst-class:: sphx-glr-signature
`Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_