This video shows a basic shell machine operation
carried out using geometry within a solid body
and then offsetting the elements.
Now, you all upgraded the file baseline_plate
in a previous video.
If not, you can either open the Solid Works file
or a parasolid file from the exercise files.
So, here, I'm going to open
the baseline_plates Solid Works part.
Now, for the second exercise with this geometry,
we're going to create a new study directly,
without manipulating the geometry.
So, go to Simulation, New Study.
Let's call this one geometry_plate.
We've set it to a static analysis, we'll check OK.
And under baseline_plate, there's just one geometry,
and it's indicated by the icon to be a solid body.
Right mouse click on it, apply, edit material.
We're going to add the usual alloy steel.
So, we apply, and then we close.
Now, we right mouse click on baseline_plate,
and now, we want to turn it into a shell mesh.
So, we define shell by selected faces,
and I want to choose a negative Z surface
for the bottom of this.
So, let's choose the face here.
I'm going to set the thickness to 0.2.
This isn't translated automatically through in any way,
so we have to input that.
Now, I have clicked on Full Preview,
so now, I can see, the bottom face is in orange,
and the top face is in green.
At the moment, the top and bottom faces
are not in the right position.
So, if you drop down to the offset option,
you can see, it's on the default,
which is to position the shell services
relative to the surface we've just picked.
So, if we change to the next icon,
you can see, the visualization
of the shell mesh has moved down.
So, this is positioning the top surface of the shell mesh
at the bottom face we just picked at the geometry.
If we change to the next icon,
this is positioning the top surface
of the shell mesh we want
at the top surface of the geometry,
so that is correct.
Now, we keep the type up here as a thin shell,
then, we can check OK.
Right mouse click on Mesh, click on Create Mesh.
We'll leave the settings as default and check OK.
Go to Boss Extrude.
If we hover over, we can see that the shell mesh
is actually positioned where we meshed it,
on the bottom face of the geometry.
Now, that might seem surprising,
but what's happening is that the mesh,
in other words, the nodes and elements,
exist in the geometry surface.
That's the bottom surface we picked.
The offset to the correct position
is a mathematical definition in the FEA input file.
In fact, there are a set of virtual reused links
to find from each node to the offset shell position.
This has important side effects that we will see shortly.
Now, right mouse click on Mesh,
and select Render Shell Thickness.
Now, there is a thickness and an offset visualization.
So, now, if we hover over the geometry,
we can see it's in the right position.
I'm going to set the visualization back to 2D visualization.
This is useful when applying loads and bound conditions.
So, let's come to fixtures and apply fixed geometry.
Now, we can only pick geometry which is associated
with the surface that we've meshed,
which is the bottom surface.
If I pick the top edge here and click OK,
I get a warning that the entity isn't on the shell mesh.
Let me clear this,
and I'll try to pick that edge surface there.
Check OK, again, I get the same warning.
clear the sections, and pick the geometry
that we have meshed on.
Check OK, then, that's accepted.
I actually want to modify this slightly,
so let's go in and edit the definition.
I want to use Advanced,
and just as in the previous exercises,
we're going to go to a reference geometry,
which, we'll use Front Plane.
Then, I want to pick a long direction one.
We'll go to an X normal to the plane, in other words, in Z,
and rotation about Direction Two, which is about the Y axis.
I check OK.
As before, I right mouse click Create Another.
Fix geometry, I want to pick that corner vertex,
which, again, is on the mesh I created.
Go to Advanced, I need to find my reference geometry,
which again, is the front plane.
Again, this time, I just want to stop translation
about Direction Two, which is the Y axis.
Check OK.
As before, this is set up at minimum constraints,
allowing the plate to shrink laterally.
Right mouse click on External Loads, apply a force.
Again, I must be careful to pick enters
which are just on the mesh.
So, this edge is appropriate.
See what happens if I choose Shell Normal.
We can't apply normal force or torque
to edges of vertices, so we must use the
select-to-direction method.
Again, I'm going to use my front plane,
and this time, I want to load in the horizontal direction,
so I choose the X direction,
and then, 1000 pounds force.
Check OK, as before, I name this Horizontal.
Now, I can copy this and paste it back in.
And this time, I want to edit the definition,
and I'm going to change the direction
to be vertical.
It's just 100 pounds force,
and I'll deselect my axle loading.
Check OK, and let's name this Vertical.
So, to summarize, we created this mesh
by directly meshing on a surface.
Then, we've used the offset controls
to move the mesh into the right position virtually.
In the next video, we're going to be applying the loads
and see what the results look like.