MSC Nastran; Patran Tutorial - Linear Statics; Thermal Stress with Solids Video Lecture | Nastran: Basic Tutorial for Students - Design Softwares

in this video I'll be performing a
linear static analysis to find the
thermal stresses in these six solids
full details of this exercise are on
page 368 of the PDF length in the video
description below one thing you'll need
for this exercise is this CSV file that
is also located in the video description
below it has all the temperatures for
each node so that would be nodes 1
through 92 here
I'll start the exercise by opening
patrin and I'll start a new patch on
database call this one problem 10 and
the units for this exercise are pounds
inches psi I'll draw a cube first that
is one unit in every direction I can
either go to geometry solids X Y Z and
hit apply or I can just type in H patch
and hit enter and I'll create the same
cube for this exercise I need six cubes
I've only created one under transform
solid I have the option of creating five
additional cubes so let me go ahead and
save the direction vector I want this to
be space the one inch apart so I would
type in two here 3p count I want five
additional cubes for my solo list if I
have auto execute on as soon as I pick
one solid they'll automatically carry
out the operation now I can go ahead and
define or create my elements for this
for these six solids so let me go ahead
and create some groups our first group
will be elements
this will contain all of my elements
later on I'll create another group
called elastic supports X this will
carry point elements for supports in the
extraction i'll create another group
called the elastic supports Y I'll carry
point elements for the y-direction I'll
create another group called the elastic
support Z and I'll do the same thing but
for the z direction let me turn on my
model tree and here you'll see the other
groups
currently we are in the elastic supports
group I want to be in the elements group
so I simply right-click and set current
this changes so anything I add after
this will be added to this group and let
me uncheck the other ones now let me go
to the meshing tab and under measures I
can match each solid let me start by
meshing this solid solid one the element
is a hex 8 automatic or the global edge
link this one
you
go ahead apply and here you'll see that
the blue indicates a hex element if I go
to home turn on the label control for
the elements I get a one to match solid
to I will simply click it change this X
20 and hit apply see element to the next
one is element three I will switch to I
will switch this to watch watch six and
hit apply the next one is wedge 15 solid
for this time and hit apply now to mesh
the next two with Ted Ted four make sure
the measures I so mash as before so like
this solid and hit apply for last one
it's a Tet 10 select the solid and hit
apply now it's important you use ISO
matched for each solid so at the end you
have ninety two nodes so have node one
here in node ninety two up here let me
turn off the known numbers now define my
elements tie the elements I uncheck this
next I'll set or turn this on and set
this group to current and you'll know
you know it's common it says the group
of the or the name of the group here I
go to meshing and go to element create
or element edit so here under the finite
elements tab I am creating an element
that is a point element and I simply can
do one of two options I can simply
select the nodes that I made in the
elements group
so simply drag and pick and head apply
or I can use the points and the Simon
Says points and now how to apply this
time and there's one small issue with
doing it this way let me turn on my
known numbers and you'll notice that now
it says 94 95 99 but we've already
defined notes at these same locations
and when I turn on the other group
elements you'll notice is sort of
difficult to read the other nodes and
that's because they are overlapping what
I have to do is do n equivalence so
after you click this and then the pnai
elements tab here you can hit apply and
this will delete those duplicate nodes
or what you can do instead is let me
switch to my next group right now I'm in
the elastic supports group for the y1
what I can do is create element edit
before I select that the points and made
my additional point elements this time
what I can do is just use the nodes and
make sure to have elements on simply
drag and pick and hit apply you'll
notice this time I do not produce the
additional nodes it just use the ones
that were there before and unfortunately
I had default group set to current so I
added those elements to this group and I
don't want that let me go and do that
let me set this one to current let me do
this again and now they are inside of
this group so I can turn them off and on
same for the last one elastic support
socks
let me turn this last one the elastic
supports Zeon let me set it current
under finite elements I'll do the same
thing notes 1 through 92 and hit apply
so this creates a third set of point
elements and if you're a bit worried
that you might have duplicate nodes that
these nodes what you can do is do an
equivalence again and show every group
just to be sure and hit apply and then
you know you're good when you only have
zero notes delete it let me turn off the
point elements and now can go ahead and
define materials for these cylinder
properties go to isotropic type in matte
for your input properties it's important
to give this material all of these
values when you 7.33 your densities 2.5
a negative 5 your thermal expansion
coefficient is 1.1 a negative 5 your
damping coefficients point 0 2 your
reference temperatures 70 degrees
Fahrenheit and this should be a point 6
out of point 5 hit OK and hit apply now
have to assign that material to these
six solids go to 3 to property solid
type and prop under input properties
type in material ok and of your
application region select all of these
solids one through six and again the
solids are in default group so make sure
you have that on add ok and apply add to
define properties for my point elements
let me turn out the elements under 0 D
properties
click grounded spring and go back to the
element properties and you'll notice at
the forum now is zero D grounded spring
call a elastic supports X for your input
properties give it a spring constant of
0.4 it's really small for your degree of
freedom it's UX click OK for application
region you want to assign this cell the
point element so make sure this filter
is on and pick all elements 17 through
64 will be added to the application
region hit OK and apply let me turn on
the elastic supports Y and turn off
elastic supports X let me create a new
one called the elastic supports Y a new
property that is for your input
properties this is point four but this
is uy hit OK for application region pick
all the point elements and you'll notice
that they're different numbers because
we are looking at the elements inside of
this group click Add ok and head apply
let me switch to the next group with
different out point elements from
element properties I'll call elastic
support Z spring constant is point four
degree of freedom is uz hit OK for
application region pick all the visible
point elements and this time they're
different numbers add ok and apply by
defining these point elements with a
really low loss per spring constant they
prevent translation that is enough for
the solution now it's time to to defy my
nodal temperatures
if you remember that CSV file
I have 92 nodes with their respective
temperatures now have to bring this file
into Patra and you do that as follows go
to the load BC's tab under LBC actions
or lbc fields click the Create speacial
icon so here it says create spatial
method should be thumb under fuel name
type in nodal temperatures we're
creating a table make sure that entity
type is node and not element our table
is in node numbers for your input data
make sure you have 92 rows here so type
in an additional 62 and insert these
rows so now I have 92 rows in addition
to the 30 that were there before click
import export the file or the CSV file
as the first line with the heading of
node and temperature we wish to ignore
this line and hit OK for nodal
temperatures you can double click it or
click at one time and that apply this
imported all the nodal temperatures
click OK hit apply down here or hit
enter and make sure that this field is
in your model tree and it's important
that you have 92 nodes in your model
since our table has mne values in the
same tab I can define nodal temperatures
call this nodal temperatures here what
I'll do is I'll use the table I just
defined usually what I will have to do
is to find the value for each node since
we have 92 that is this too much work
and in this example I just use the
spatial field to make it easier on me
for application region we wish to select
femme entities and it's always nodes and
right now you'll notice I can pick any
nodes and the reason is because the
group with my nodes is hidden if I check
it it'll be unhidden so when I go back
here go back to the application region
if I pick all of them I'll pick all one
I'll pick all ninety two nodes added to
the application region hit OK and apply
let me hide that's already headed let me
zoom in you'll notice that for each
corner here I've zero degrees so this is
node 1 9 and so on the top right I have
noted 92 and some pouring again to have
92 nodes in your model or else you might
have a node that's that has a nodal
temperature that is incorrect another
way to view this load is to go to LBC
actions and select show contours or plot
contours once I'm here I'll select
object temperature existing set as nodal
temperature and you're select data
variables temperature and select the
group with your elements inside of it
and hit apply here you get a clean view
of our temperatures your defined again 0
here and 600 at this at these points
here let me clean this and now I can run
this analysis go to the analysis tab
click analyze entire model click apply
let me turn off the model tree once the
analysis is done go to the analysis tab
and click X DB and hit apply to import
results go to the results tab and one
thing we need to compare
that the deflection is forming zero zero
four one inches to my von mises stress
tensor is zero so I'll view the
displacements first so again go to quick
plot French deformation select the sub
case these displacements and this
deformation it hit apply and you'll see
I get a point zero zero four one if you
want to clean up the numbers you can go
under fringe attributes go to label
style and switch this label formats are
fixed it'll K and apply and again is
still not clean enough so say I want to
do four significant figures
and once you type in a value hit enter
to make sure it takes your value it did
it before so for hit enter click OK and
apply and now we see my values clearly
displayed it's point zero zero four one
inches and to make sure it's the same
for each point or corner I can go to
cursor displacement translation I hit
apply
make sure those cruisers in here go and
select the individual points you see
they're all the same pretty much and do
the same for the other points click
cancel and one lesson to view are my
stress sensors clean this up go to
result plots fringe scroll down and
select stress tensor make sure this is
von mises and hit apply you'll notice
that the values are not exactly zero let
me go ahead and review my material for a
moment here on your mat right click and
modify every value here seems to be
defined properly
hello can just set apply let me review
my elastic support properties so this is
pointing for UX and supply to the right
elements same thing for this one point
for ye y
the other point elements one for uz goes
to the other elements and for my
property
so using this material supply to solids
one through six
let me reanalyze --is
I mean port the results again review my
fringe for stress sensor and this time I
get a zero let me view my deformations
to here I should have what I had before
and here at the bottom you can see it's
a point zero four one one like before if
you want to overlap these you would do
it as you did before by going to quick
plot fringe save this file and this
concludes this example