MSC Nastran; Patran Tutorial - Linear Statics; Principal Stress and Stress Transformation Video Lecture | Nastran: Basic Tutorial for Students - Design Softwares

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in this video over perform a linear
static analysis to find the principal
stresses on this loaded beam full
details of this exercise on page 323 of
the link PDF in the video description
below I'll go ahead and switch over to a
new session the patron make sure this is
a new session you've just opened I'll go
ahead and create a new file save it here
and call it problem 3i I'll go ahead and
click OK here our first begin by saying
the units are in inches pounds in psi
I'll create my first two surfaces by
going to the geometry tab and under
surfaces I'll be using the XYZ method so
first I'll start from the point 0
negative 6 0 and I'll use a vector going
in the X 20 inches and the Y 12 inches
and the Z 0 inches and after I click
apply see my first surface is created
using these values 2012 and 0 here I can
then click this point Oh drop point 4
here and I'll use the same vector to
create my second surface to make a guy
later on for my results I'll create my
five points for ABC and the second a and
B so here under points click XYZ I'll go
ahead and type in my first point which
is that 10 6 0
Mikan point is at ten five point five
zero my next point is at 1000 the next
point is at 10 negative five point five
zero and my last point is at 10 negative
six zero close it and click apply
see the the points are hard to see here
where you can do is go back to the Home
tab and turn on the point size here and
now you can see the points that we've
just created now I'll go ahead and
create my material by going to the
properties tab under isotropic
click or type in a name of material
under your input properties give it a
Young's modulus of 3 e 7 psi and a
Poisson ratio of 0.318 click OK and
click apply to create this material next
we want to assign this material to these
two surfaces so here under 2d properties
click shell call this property under
input properties use this material
you've just created for your thickness
give it a value of 1.5 35 inches click
OK
for your application region we wish to
apply this material to these two
surfaces so select this surface then
hold the shift key and select the
surface and you should see 1 & 2 here
click Add ok and click apply to assign
the material to these two surfaces next
I can move on to defining my boundary
conditions I'll first define a nodal
displacement constraint this first
constraint called R X will prevent
translation in the x-direction so here
under translations you have to supply
values for just T 1 so I can type in 0
comma comma click OK we wish to apply
this to this metal curve so here is
select only curve or edge so you only
select curves and not points or surfaces
select this middle curve make sure this
cursor is in this box so when you click
on something it drops that value in here
and as long as you see this line is
highlighted orange you know you've
selected the correct object click Add
click OK and apply you see the one there
saying you've assigned a boundary
condition here next we want to make two
rollers that prevent translation in the
y-direction so I'll call this next one
ry under input data for my translations
that we
to prevent t2 motion so here I'll delete
the zero for the X and type in zero for
the y there click ok under your
application region we wish to select two
points so here I will click pointer
vertex so I only select points so here
I've selected the point on curve 3 of
surface 2 and I can add it now the next
point I'll do is this point which is
point 1 on curve 1 of surface 1 so then
I can add this also click OK and apply
so now we have the two rollers here and
here next I'll make a new constraint
called RZ and this is meant to prevent
translation in the Z or t3 direction and
this will be applied to both the left
and right surfaces so here I'll just
select surface or face so I only select
surfaces so like surface 1 hold the
shift key and select surface 2
click Add ok and apply now I need to
define my force under nodal force click
this icon call it f for your input data
we have 0 and the X you can leave a
blank have a downward force of negative
eighteen thousand 440 pounds in the Y
and we have nothing for the Z direction
so click OK for application region we
wish to saw like one point so select
point over your text select this point
so it's point two of curve 2 of surface
1 click Add ok and apply and you'll see
it defined here now can go ahead and
mesh these two surfaces I'll use mesh
seeds to guide the mesh so first I'll
define 24 elements going up and down the
verticals so I want 24 elements and then
I simply select these two surface or
curve
and they're automatically seated next I
want to make twenty elements for this
curve in this curve so I type in 20 here
I delete these objects simply drag and
select those see it is automatically
generated here because I have auto
execute on and I do the same thing here
automatically seats these curves to can
then go and mash my surface by selecting
these two surfaces here so make sure you
have two in one here and click apply now
let me go back to the Home tab and hide
my mesh using this icon here what the
measure has done smashed this surface
independent of this surface
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so to show you when I go to display for
night elements and when I click edges
here and hit apply you see that the mesh
boundary is highlighted in white in
reality this entire section should be
one entire mesh but when I go back to my
actual mesh it appears as if it is but
in reality it's not what I have to do is
do an equivalence to remove the
duplicate notes that are here so let me
go back to faces here click apply let me
reveal the geometry again here are under
label control you can select node and
you zoom in you see that you can clearly
clearly read the known numbers for these
but the ones in the middle you can see
that there are multiple numbers are
indicating there are multiple nodes at
this one location and we have to go
ahead and remove these duplicate nodes
to do this go to the meshing tab click
equivalents and you can close this FEM
attributes window and make sure this is
equivalent here go to the bottom and
click apply you see that the pink
markers indicated which nodes have been
removed and now you can see that there
is only one number at the same location
so if I go back to display finite
elements and just show the edges and
click apply let me hide the node numbers
let me hire this to clean it up
now you can see what was before a
two-body section is now a one complete
section so now I can go back to the
faces and hit apply
I mean reveal the geometry again now I'm
done meshing and that can go to the
analysis tab and click entire model to
analyze this and hit apply once the
analysis is done I'll import my X DB
results here and I'll hit apply to
import I go to the results tab now the
first thing I'll go ahead and do is zoom
into this location
I'll larger this window now we've been
asked to find the stress tensors for
these five points so under the results
tab click tensor so like of this case
select this result and sure it says
component here and we just wish to see
the X the Y and the X Y results so and
we want to view this for just a few
nodes so here under target entities
which is this icon I wish to just focus
on a few select nodes and I'll select
this by individually picking these
points I made a at the beginning of the
video so select this point hold the
shift key to select multiple nodes
simply select these
you should have five notes selected here
so now when you click apply you see that
there are values there so when i zoom in
you can compare these values to the ones
we should get so to compare a few values
my x-values I should be getting a value
close to 2200 at B 2500 at a 0 at the
middle 2200 at the bottom and 2500 at
the bottom fiber so let me go back to
Pat Ron to compare just the ax results I
will turn off X when y Y and just have
the x1 on click apply now if i zoom in I
can see I get it looks like 2300 here
and the last time this problem was done
they received 2300 and it's close to the
value of 2500 for point B I should be
seen like receiving a value close to
2200 so back here I get a value of 2100
and that is actually what they got last
time in the middle I should get a value
of 0
last time they received a value of 100
and if i zoom out slide the sulfur I can
see I get a value of 120 last time this
problem was performed they received the
value of 2400 I should actually get a
value 2200 my zoom out and slide it to
the bottom again that's actually what I
I do get the bottom I get up well looks
like 2600
and that is what they got last time but
we should be seeing it receiving a value
of 2500 now here for your shears X Y you
can simply turn off the X direction and
turn on the X Y and click apply and then
you can do the same thing I just didn't
just compare so we should be getting so
here at the bottom last time this was
done we got a 54 here at the bottom but
we should actually get zero for the next
plane we got 100 psi we should be
receiving 120 you can do this and
compare the other points next I want to
do or find my principal stresses so I
can switch show as to 2d principle and
for now I just want to view my maximum
principle stresses so then I click apply
I go back to the PDF I can start
comparing these values so I get twenty
six hundred twenty four hundred seven
fifty twenty six twenty four seven
hundred or so 160 then I should be
getting looks like 11 and four for the
other ones so twelve and the other one
is 29 but I should be receiving a zero
there and the four it's close to zero
the next thing they wanted us to view or
my Sigma X stresses and this can be done
as follows back in the results tab click
fringe here under stress tensor select
this for quantity select the X component
before we click apply here let's fit the
model in the view so click fit view here
and there
have higher geometry you'll notice that
there are points here and sort of up
skewers of you after I click this at
Heights the points so now I can click
apply and the numbers are so here you
can click refresh graphics and click
apply again or if you want to reveal the
displacement too you can click fringe
deformation select the same stress
tensor select Beck's component for
quantity and for displacements select
this translational click ok or apply and
here we want to remove this blue
undeformed view so I can go back to the
form attributes and uncheck show
undeformed and click apply and you'll
see this resembles image here I love you
my stresses on the y2 so let me go right
now we are in the form attributes so
I'll go back to select results under
quantity select the Y component and
click apply you'll see it looks like
this view
next I'll be my towel XY stresses so
your elbow click the X Y component and
click apply next thing I want to view is
my orientation angle of the maximum
principle stress so here under fringe
result you'll see principle stress
Direction click that and click apply and
the view updates you know see it
resembles of this image make sure to
save your work and this concludes this
example