and welcome!
and welcome to this video introducing
HFSS in the student version of the
Ansys Electronics Desktop or AEDT for short
and in our videos, we have presented a simple
air filled rectangular waveguide, a dielectrically
stacked rectangular waveguide and in this video
we will add a little twist to that
rectangular waveguide and a bent rectangular
waveguide and waveguides in themselves
they are used to guide the fields inside and
the twist and the bend should be implemented
gradually otherwise the fields can be distorted
and therefore you actually distorting your
intended signal
and twists are primarily used to change
the polarity of the signal whereas bends
can be used to how to fit the physical
waveguide to a smaller physical space.
So, let's get started!
So, here is the interface of the tool
with the HFSS design for the WR15 waveguide
and this is the waveguide cavity already created
using variables as dimensions
and I will use this model again for creating
the bend and the twist.
I rename the project
and check that the unit type
is also in millimeters.
So, let's go ahead and design and analyze
this twisted geometry.
If you haven't copy and paste design
and rename it.
Delete the output port of the waveguide cavity
and switch to the face selection mode
by pressing the F key on the keyboard.
Remember there is always more than one way
of doing things in AEDT.
You could also with draw panel open
you can also switch the face selection
by using the dropdown menu on the
select panel.
Select the face along the poisitive X axis.
Right mouse click select edit -> surface ->
create object from face
and notice you have a 2D object is created
under the sheets category.
Edit the name of that object call it something.
Now, select and draw a line
draw line command. Place the first coordinate
on the face center of that sheet
and then the other coordinate anywhere else
in the 3D modeler window and notice that
one polyline is created under the lines category.
Double mouse click on
that create line command.
Edit coordinates of that line segment.
Enter the values as shown
and its good practice
to use variables wherever possible for a more
robust design.
After editing click OK to accept the changes.
and with the sheet and the polyline selected
right mouse click in the 3D modeler window.
Select edit then sweep along a path.
a new window pops up and in the cell
next to the angle of the twist enter -90
and keep the rest as defaults
click OK
and notice the twisted geometry is created
in the 3D modeler window
and observe the rotation of the face
of the waveguide cavity. Also, notice that the
sheet object is modified to a solid type
in a model tree window and select the face
along the positive X axis. Right mouse click
select edit -> surface -> sweep face
along the normal and in the pop up window
enter the dimensions as shown.
Click OK to accept.
Rename the newly created object.
Unite all the objects to create
a single object
and proceed to create the wave port
excitation on the face along the X axis.
and this concludes the geometry creation
required for the waveguide twist analysis.
Creation of the ports and the analysis is the
same as the rectangular waveguide.
So, go through our previous simulation setup
for the straight run waveguide
and apply to this model
and check the validation tool
before proceeding just in case
we have some errors and once the analysis
is done we can view the results.
Here is the phase constant plot for
port input with the markers denoting the cutoff
frequency and for the different modes
Here is the phase constant plot
for the port output and the markers
again denoting the cutoff frequencies of the
different modes
and here is the plot of the electric field inside
the whole geometry.
Here is the animation of this plot.
Waveguide bends are also of two types
E-bends and H-bends.
Okay let's proceed with the H-bend geometry
creation.
Copy and paste this HFSS design.
The WR-15 and rename it.
I rename this project as waveguide_bend
and delete the input port of the waveguide
cavity and we will use a relative local coordinate
system to create the bend geometry and
the sweep option.
So, lets proceed to the geometry creation
and select the face along the negative X axis.
Right mouse click select edit then surface
and then create object from face
and with the draw tab open select the offset
origin option and click anywhere along
the Y axis in the 3D modeler window.
Navigate to the relative coordinate system
in the model tree.
Double click on it to edit and change the name
of this coordinate system and change the origin
position as shown.
Let's go ahead and use a variable for
the radius of the bend. Input a dimension
in the window and click OK to proceed.
Edit that name of that 2D object in the model
tree window and with the 2D object selected
right mouse click on the modeler window.
Select edit -> sweep -> around an axis and
for the sweep axis option select Z axis for the
angle of sweep input -90 degrees and keep the
rest as default and now you can see the bend
for the waveguide is created
in the 3D modeler window and notice that
the relative coordinate system is selected
as the reference and select the face of that
bent geometry along the Y axis
and right mouse click select edit -> surface
and sweep faces along a normal
In that pop up window
enter the dimension as shown and
click OK to accept
and rename the newly created object.
Now unite all the objects to create a single
geometry and proceed to create the wave port
excitation on the face along the positive Y axis.
Now we are all set to proceed with the analysis
and check the validation tool before proceeding
just in case we have some errors
and once the analysis is done
we can view the results.
So, here is the phase constant plot
for the port input with the markers denoting
the cut off frequencies of the different modes
and here is the phase constant plot for the
port output with the markers again
denoting the cut off frequencies
of the different modes.
So, here is the plot of the electric field inside
the whole geometry
and here is the animation of this plot
and this is the beauty of the electromagnetic
simulation. You can visualize how the fields are
guided through any complex geometries
very easily.
Thank you for watching this video.
As we create a model geometry for a twisted
waveguide and a bent rectangular waveguide.
View the simulation results
and view the field patterns.
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and watch our video modules on
all of the Ansys simulation tools
as well as related topics.