MSC Nastran; Patran Tutorial - Superposition of Linear Static Results Video Lecture | Nastran: Basic Tutorial for Students - Design Softwares

this video I'll be demonstrating the use
of superposition for the linear static
analysis of this loaded plate full
details of this exercise are on page 372
of the PDF linked in the video
description below I'll first begin by
starting patran here start my new patron
database I'll call this on problem 11
the units for this example are in inches
pounds and PSI now according to the
example I'm to define three sub cases
that ultimately add up to the actual
vertical displacement so back in patran
I need to define the three sub cases so
head okay here on the right I'll define
a curve or before that define my
coordinate system using the three-point
method this is a cylindrical coordinate
system I'll leave the defaults here and
after a head apply you'll see my new
coordinate system here I'll create a
curve using the line by XYZ method so
from the origin this first curve is to
have a length of four and you can click
apply your head enter then I'll define
another curve that starts at this point
point two and it'll have the same length
of four inches
see my second curve here next thing I
want to do is define or create my
surface by rotating these two curves
about the y-axis here are not the wax
z-axis
so to do that go to the surfaces revolve
method here four axes I want to do this
about another third so axis three of
coordinate system zero my total angle of
rotation is ninety degrees and once I
select these two curves
it creates the two surfaces and this is
up and this is sub case a now I define
sub case B and C so to define this
geometry under transform I click surface
here I want to rotate the two surfaces
so make sure that says rotate my
rotation angle would be 120 degrees and
my repeat count would be two so after I
select these two surfaces and since I
have auto execute on here as soon as I'm
finishing selecting surfaces that
automatically creates the other surfaces
and here I've accidentally selected the
surface too and not underneath that so I
can either undo it or either I can undo
that action and only select the surface
as shown here
or what I can do is if I go to geometry
actions delete I can delete the surface
if I've accidentally created it here let
me undo that so now that I have my
surfaces define for sub cases a B and C
I can define my materials by going to
the properties tab here on your
isotropic the material name would just
be mat under input properties I'll have
a Young's modulus of e 7 psi and a
Poisson ratio of 0.33
click oh can it applied to create this
material now to assign the material to
the surfaces app to go to 2d properties
inhale it and select shell for property
set name call it prop for my input
properties select this material that we
just created for your thickness type in
the value of 0.25 inches hit OK for your
application region we wish to apply this
to all the surfaces so you can either
drag and select surface 1 through 4
where you can hit pickle and all select
all those surfaces click Add
ok and hit apply after you've done this
will define our boundary conditions by
going to this tab under displacement
constraint I'll call this first one edge
constraint
from an input data I'll prevent
translation in the x y&z direction from
my analysis coordinate frame made sure
to pick this coordinate system here in
the middle it's the cylindrical
coordinate system and it's called Core 2
1 click OK for your application region
make sure you only have curves selected
here so you can only pick curves at this
first one and not these other two ones
click OK and hit apply from the next one
I'll call it symmetry constraint for my
input data
I'll prevent translation and the Y so
open comma 0 comma then close it and
I'll prevent rotations about the X so
open 0 comma leave a blank there comma 0
then close it you'll use the same
analysis cornet frame hit OK for your
application region select this curve and
every other curve you see me select here
you'll notice he turned orange when
you've dropped them in this box here
click Add ok and apply and one last one
the point constraint for my input data
I'll prevent translation in the X the Y
not the Z so comma blank close and I'll
prevent rotations about X about the Y
and about the Z you use the same nicest
corner for a mess before chord one for
your application region just pick the
point icon here and select this middle
point add it hit OK and apply now it's
time to definer loads here under LM in
uniform for subcase a hit pressure
this pressure and select the element
type 2d for your input data type in 50
psi click OK or for your application
region select the surface icon here so
you're gonna select surfaces 2 and
surface 1 hit OK and apply now I need to
make a shear constraint or load here
under element uniform hit distributed
load again for your new set name type in
V for element type type in 2d for Impa
data our load is as follows open 0 0 100
and you believe that blank hit OK for
application region select this edge here
added ok and apply I'll create a new
just rip it allo to call them for a
moment and this will define the load for
sub case C and this would be the load
for sub case be here so for m for your
Impa data you can just leave that blank
here i will define a value of 500 0 0
click OK for application region select
this curve added ok and apply and now
you can see my loads and boundary
conditions here I'll go ahead and mesh
this before that I have to define a few
mush seeds so click on your mesh sheets
uniform I wish to define a requirement
that says I need 6 elements through this
curve and I'll select this curve and
every other one you see me pick to make
this easier on this you can use a sweet
by Conner we set graphics here to remove
the markers I simply hit each curve you
see me select
once I'm done defining these seeds I can
go to the measures icon here for surface
and make sure it says quad quad for here
I'll mesh the surface this one in this
one and hit apply next I'll switch the
element shape to tria here I'll select
this surface surface one and I'll hit
apply so now I've defined meshes for
each surface one important thing to note
is that I'm gonna go to display and show
you my finite elements here by select
edges here and hit apply clean this up
and I'll hide my geometry by clicking
this icon here and notice that right now
the mash is not one entire thing here
you'll notice it's actually two separate
bodies so let me show you the mesh so
visually it looks like it's all one
continuous mash where this these
elements are linked to these elements
here in reality I'm going to switch the
edges here there's actually a divider
here indicating they are separate meshes
and I need to go ahead and crack this if
I go back to the meshing tab and click
equivalence and click apply it'll go
ahead and remove the duplicate notes
that were here before so now what I have
in the fact is a fully linked mash so
let me switch it back to faces and hit
apply so now these elements are fully
linked to these elements after I've
equivalence and the way I got to this
FEM attributes form is I went to display
for night elements
I'll go ahead and close this and was the
last thing before I analyze this I turn
on the model tree and view my boundary
conditions
let me display my geometry it looks as
if the boundary conditions I've been
applied to just these few nodes here but
if I go to display load BC element props
and I turn on showing them only and hit
apply and then I turn off and on my
boundary conditions you see the true
application of the boundary conditions
where when I defined them I define them
to the various curves and surfaces I'm
gonna have this option on showing fem
only I see an actual representation of
how the loads are applied out the nodes
so let me uncheck this and hit apply and
let me turn them off and on again and
you'll see that they're back to the
original way to analyze this go to the
analysis tab analyze entire model make
sure you're in this form and hit apply
here I've received the message saying
that the coordinate system used for the
nodes is different from the coordinate
system used for the boundary conditions
so I have to go ahead and crack this
click no here go back to the meshing tab
scroll up to this form and under action
go to show node location and simply
select a few nodes and I'll show you
what I'm referring to so here for these
nodes I see that the reference and
analysis coordinate system are using the
global system which would be this one
here X Y Z here I have to go ahead and
crack this so go to action modify object
this node method is at it check analysis
and reference
make sure you have quarter one for both
of these
and if we're no list simply pick all the
nodes and hit apply you get be back here
to saying that the operation has been
performed and this time when you go back
to show no location and you pick a few
nodes you see that the reference and
analysis cornices summer the cylindrical
ones hit cancel here go back to analysis
click analyze entire model and click
apply to reanalyze 'as hit a yes here to
replace the wolf files you made you
don't notice that message doesn't come
up again go to access results XD be it
applied to an import go to results in
here let me hide the markers here i'll
use the cursor tool and i'm basically
interested in the vertical displacements
so i've selected this sub case i'll
scroll down to translational
displacements and view the z component
when i hit apply this in window pops up
and i simply put the nodes that i want
to view the results for
and here I look at the values and that
can already tell they are not correct
I'll have to go ahead and look through
the various values I've defined for the
example and see where I've misplaced the
value so here I will pass on ratio point
two two and actually should be 0.33 hit
OK here and the ply and again the way to
do that is you right-click and modify
simply change it okay and hit apply let
me make sure I've defined the property
properly so I'm using that material and
the thickness is correct it okay and
apply I can tell I've defined my
boundary conditions properly and you'll
notice the CID here equals 1 which means
it's using this coordinate system in the
middle and then the middle I defined
that boundary condition crackling the
pressure is cracked and my distributed
loads will appear correct so I have a
feeling it was at Poisson value that was
then cracked go to analysis click
analyze entire model and hit apply
override your previous files once that's
done go back to X DB import these
results go to the results tab click
Cruiser
click translational displacements and
view the Z component hit apply and for
some case a I get a value of negative
point six one seven for subcase B I get
a value of point six nine six and for
sub KC I get a value of negative 9 or
negative point nine six zero inches and
let me open Excel real quick let me do
the addition real quick
I'm gonna have these up I get a value of
negative point-eight eight inches I'm
going to compare this so the value I
should get I do get negative 0.8 8
inches
on one last thing you can review is
under quick plot go and click fringe
scroll down here under French result
under your stress tensor and here what
you could do is view your radial
component of stresses here what I have
to do is
I may have to actually transform these
so here under result plots click fringe
select stress tensor like before the
quantities X component here under
coordinate transformation click CID hit
and select this coordinate system chord
1 and hit apply now you can view the
radial stresses you can view your hoop
stresses to by switching to the Y
component clean this up save your file
and this concludes this example