Here at SimScale we recognize that most
of our customers are not just interested
in solid cad models but more importantly
the fluid that flows in and around them.
This is why we have created a tool that
enables you to build a fluid volume
within the SimScale interface,
you can
see it here in blue.
There is a new menu with three options:
"Enclosure", "Open inner Region", and "Closed inner Region".
Initially, we are going to focus
on "Open inner Region".
We first need to select our boundary phases
which lie between the external environment and the internal.
Then we need to pick one
single internal seed face.
Then SimScale will build the internal fluid for us.
The operation is now complete and if we switch to transparent,
we can see the
fluid volume
and how it wraps around our solid components.
There is one additional
step we could have made
to switch to keep existing parts.
Here, when we create
the internal volume,
our existing solid parts are retained.
This of course also
works with more complex geometry.
Here we have a small electronics box.
Again, we are
going to create an open inner region,
first picking our boundary faces
on the
external again
and then one internal seed face.
Here we are going to keep
existing parts
and when we press start,
SimScale will build the internal fluid
for us.
The operation is now complete.
I am just going to make the volume
transparent
so you can see what it looks like on the inside.
The second option we have is to create a volume within a closed region.
Here we
have a theater and with some very
accurately modeled people sitting on
their seats.
The geometry is actually fairly complex,
which is quite a good
example,
and so here we are gonna choose to create a closed inner region.
This time
we just pick one single internal 
seed face
and press start.
And again, SimScale
builds the volume for us.
Once it is created,
again I can make it
transparent just so you can get an idea
of what it looks like and we can zoom in
and take a look inside.
We have a second example of the closed volume region.
This
is a similar electronics box as before
with the holes closed up this time.
So you can see all the components,
the heat sink and everything inside.
I'm going
to choose to create a closed inner region,
picking one of the internal faces no
need to hide everything outside,
keeping the existing parts
and once again we
have a beautiful flow volume
successfully created.
The final option is
to create an enclosure,
so this would be if we have external aerodynamics
around
a car here or a building for example.
So we need to size the enclosure first,
and once we're ready,
we simply press start.
So this time we have essentially
created an air volume that represents a wind tunnel.
This would also work with a half
symmetry model, so here we simply build
the enclosure over half of the model
instead of all of it.
Obviously this runs in half the time or gives us a bandwidth to have
a finer mesh.
