MSC Nastran; Patran Tutorial - Linear Statics; 2D Shells in Spherical Coordinates Video Lecture | Nastran: Basic Tutorial for Students - Design Softwares

in this video I will be performing a
linear static analysis using 2d shells
and spherical coordinates full details
of this exercise are on page 340 of the
PDF linked in the video description
below and I'll simply move over to new
Patran session make sure this is a new
one you're not carrying over or you're
not continuing on from a previous
example I'll create a new file actually
I have to make a new folder here on my
desktop called problem 5 and here I'll
make a file called problem 5 click OK
here offers begin by saying the units
for this example are in inches pounds
and PSI under the geometry tab I'll go
ahead and create a coordinate system
using the 3-point method here we're
using spherical coordinates for my
origin
we'll start at 0 0 0 0.9 third axis will
be 0 1 0 and a point on plane 1 3 will
be 1 0 0 so when I click apply see that
my car runs down to X my T runs on this
length and my P goes on this way now
I'll be creating this model using just
the machining tools but first I have to
create a curve YZ in the 2d arc method
so here my radius would be 10 inches
much to our angle will be 0 and my end
angle will be 45 degrees a construction
plane list this will be using the third
axis in the coordinate system 0 which is
the z axis and this
global coordinate system here a center
point will be the crosshair here when I
click apply you'll see my object drawn
here but this is actually not how I want
to draw a soul and do this my start
angle will be 270 my end angle will be
315 I click apply now you'll see it's
drawn here now I can go to the meshing
tab and match this I'll use a one-way
bias method to create my seeds here I
have the arrow indicating that l1 starts
here and l2 ends here as shown in the
diagram here my l1 and l2 will be 0.36
inches in my LT would be 0.72 inches I
select this curve see it smashed here
I'll go and select curve measures select
this curve and click apply now here the
feedback is 15 elements I've been
created now I have to go ahead and sweep
this three-dimensionally to do this I go
to the FEM action sweep also like these
elements is sweep or actually have to
click or reduce my filter to just these
and beam elements so now I can click and
select click refer or reset graphics of
so if it doesn't clean up here so so far
I've selected these beam elements here
what I will do is sweep these elements
about the Y so here I would change this
to coordinate system access to or what
you can do is simply click these 1 2 & 3
icons and I'll automatically drop the
value here so here I want access to a
coordinate system 0 you'll see it
dropped it in
I want my sweep angle to be 90 degrees
and for my mush control I want ten
elements click OK and click apply I
forgot to do something I forgot to
delete my original elements so now what
I have here are two dimensional elements
and beam elements along this length and
that's not what I want so I'll undo that
I'll click delete original elements so
when I click apply it deletes the beam
elements here and just creates these 2d
elements to verify I've done this right
you can go to the Home tab click label
control type in element numbers and if
you did have beam elements here you
would see numbers in addition to 12 13
14 and so on you can see additional
numbers here indicating they're
additional elements here but since I
checked the lis original limits they are
not here and one less thing I have to do
back in the meshing tab I have to modify
my nodes click Edit I want to modify my
now system reference coordinate system
for my analysis coordinate system I wish
to use this spherical coordinate system
called chord 1 my reference coordinate
system will be just this original one
chord 0
I want to supply to all the nodes you
can drag and select or just pick all by
clicking this icon click apply here
you'll see that my 166 notes I've been
modified now I can go ahead and move on
to my properties
so on your isotropic call this material
material under input properties elastic
modulus is 10 e 6 PS I'm a Poisson ratio
is 0.3 click OK and apply now to assign
this material to this elements let me
turn off the numbers here and turn off
label control
I can under properties select 2d
properties shell here I'll just call it
property under input properties I select
this material my thickness is point zero
five inches click OK for your
application region wish to select all
the shell elements or you can click
quads I'll actually let you select all
the quality elements but if you do it
that way you select the Koala quad
elements but you have not select the
tria elements here try a so to fix that
and you can do is in addition pick this
fill turns like these regions select all
the shell elements here so here when I
select all of these you see the orange
ones are highlighted or the green ones
are highlighted too so I can pick all
atom ok and apply so now this these
elements have material signs of them I
can move over to my boundary conditions
now under displacement constraint I will
make my first constraint and I'll call
it edge under input data
I'll prevent translation in the two
direction so comma zero comma close for
the Nasus coordinate frame you will
select the spherical system click OK
your application region
you will wants us like these top edges
here here we're dealing with just the
mesh so we don't have geometry to deal
with we have a fem here I'll go ahead
and use the polygon pick two and close
these top nodes add them okay in the ply
and you'll notice I missed one so I have
to go ahead and modify this so under the
Home tab turn on the model tree open up
the LBC section and right-click edge and
modify this is OK click OK and for your
application region just add this one
node here click Add ok and apply now we
see the conditions there for the top
edge next I'll define a symmetry
condition so hair under nodal click
displacement constraint call the
symmetry for your input data I'll just
provide translation in the third
direction so the one and two are
applying for the third as a zero
coordinate analysis coordinate system
should be this one again so cord one
click ok for application region you want
to go ahead and select these nodes here
so this could get a little tricky so
I'll go ahead and reorient this and I
want to select this edge and this edge
too so I'll just simply drag one doing
as close as possible add these nodes
and oriented so you can select these
other nodes here and make sure you have
an accidentally chosen this node or that
node select the ones along this length
and this length click Add and here to
verify you'll see that they're orange
indicators around the notes you've just
selected so click OK and apply let me
turn these off let me create a new one
called Center from my input data prevent
translation in the one direction or
actually the two direction so drop a
zero there leave one and three blank
click OK your application region simply
select this middle node here added ok
and apply just see the marker there and
I want to provide rotations for all
these elements or nodes so I'll create a
new one called rotations here I'll leave
that blank
here I'll prevent rotation for the one
two or the four or five and six
directions make sure you have a nice
corner frame cord one for application
region you select all the nodes click
Add ok and apply so one thing to note is
when use another coordinate system other
than this one Korda with 0 you have in
parentheses an indicator of what
coordinate system this boundary
condition is using so here I'm using
coordinate system 1 which is a spherical
coordinate system here I can see I'm
using coordinate system one coordinate
system one same for the last one
coordinate system one now I can go ahead
and apply my pressure so here under the
boundary conditions tab click pressure
type and pressure as a named target
element type is 2d for your Impa data
you will apply a top pressure of 200 psi
click OK for application region you can
leave this selected try your quad
elements and pick all all the elements
have been selected added ok and apply
now I can go ahead and go to the
analysis tab and analyze this entire
model and apply
once the analysis is done hi my model
tree I'll inform my xdb results now can
view my results and make sure to clean
this up using the reset graphics icon
now the first thing we'll go ahead and
view are my global X&Y displacements so
here click the spaceman translational
click X component or I'll actually be my
fringe slice my translational quantities
X component our coordinate
transformations should be chord 0 right
click apply you can see my values here
so here I've displays point 0 1 inches
in here up displaced 0 inches where's
this point 0 1 actually and this point 0
3 inches so when I view the results here
at the carefully look here
you
and you are all compared to my global
translational displacements here my
global translational y displacements
here have to go ahead and obtain those
so I've seen my X now I can see my Y now
it's a viewer radial displacements so
the membrane you have to these
coordinate transformation coordinate ID
and select the stop warning system the
spherical one click the X component and
hit apply see here we've obtained point
zero one inches in point zero one three
eight I look at the values here that I
believe that is what I do get so change
in r2 here if I want to view my my
radial stresses I'll scroll down and
click stress tensor switch the quantity
to or yeah the quantity tax component
and hit apply here you can view your
results I get 85 psi here six PSI their
can compare it here
so here you see I get eighty five and
six for my next stresses I'll get a
twenty thousand and twenty thousand
approximately so I'm going to switch to
the Y 20,000 20,000 here
compare this to the results here and for
my last one I would get a twenty
thousand two so switch over to Z
component and hit apply so twenty
thousand and twenty thousand again if
you want a better view of the numbers
where you can do is go to the display
attributes scroll down to label style
turn on fixed hit okay and hit apply now
you can see the exponents been removed
and it's just purely a number twenty
thousand psi for here and here clean it
up save it and this concludes this video