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Frequently
...
Asked
...
Questions
...
1.
...
I
...
have
...
trouble
...
applying
...
a
...
displacement
...
constraint
...
in
...
the
...
cylindrical
...
coordinate
...
system.
...
2.
...
I'm
...
trying
...
to
...
plot
...
stresses
...
in
...
a
...
specific
...
area,
...
but
...
it
...
doesn't
...
seem
...
to
...
work.
...
3.
...
How
...
do
...
I
...
read
...
points
...
in
...
from
...
a
...
file?
...
4.
...
How
...
do
...
I
...
automatically
...
number
...
keypoints
...
with
...
an
...
array
...
parameter?
...
1.
...
I
...
am
...
working
...
in
...
the
...
global
...
cylindrical
...
coordinate
...
system
...
(CYS=1).
...
I
...
am
...
able
...
to
...
create
...
the
...
geometry
...
in
...
this
...
coordinate
...
system.
...
I'd
...
like
...
to
...
apply
...
a
...
displacement
...
constraint
...
on
...
an
...
area
...
in
...
the
...
theta
...
direction.
...
I
...
tried
...
setting
...
UY=0
...
for
...
this
...
area
...
but
...
this
...
seems
...
to
...
take
...
effect
...
in
...
the
...
global
...
cartesian
...
coordinate
...
system
...
(from
...
looking
...
at
...
the
...
symbols
...
that
...
appear
...
in
...
the
...
graphics
...
window).
...
How
...
do
...
I
...
apply
...
a
...
displacement
...
constraint
...
in
...
the
...
theta
...
direction
...
in
...
the
...
cylindrical
...
coordinate
...
system?
...
Constraints
...
are
...
applied
...
to
...
the
...
nodes,
...
which
...
are
...
in
...
the
...
nodal
...
coordinate
...
system.
...
The
...
nodal
...
coordinate
...
system
...
is
...
ALWAYS
...
Global
...
Cartesian.
...
What
...
you
...
will
...
need
...
to
...
do
...
it
...
to
...
'rotate
...
the
...
nodes
...
into
...
the
...
active
...
coordinate
...
system'
...
using
...
the
...
NROTATE
...
command.
...
If
...
your
...
active
...
coordinate
...
system
...
is
...
cylindrical,
...
NROTATE
...
will
...
rotate
...
them
...
so
...
that
...
y
...
will
...
be
...
the
...
tangential
...
direction
...
for
...
each
...
node.
...
Here
...
is
...
an
...
example:
...
/prep7
...
et,1,plane42
...
blc4,0,0,10,10
...
CYL4,0,0,5
...
ASBA,1,2,,,DELETE
...
esize,0.5
...
amesh,all
...
csys,1
...
nsel,s,loc,x,5
...
!select
...
nodes
...
on
...
curve
...
d,all,uy,0
...
nplo
...
!See
...
that
...
y
...
constraints
...
are
...
all
...
pointing
...
in
...
the
...
global
...
y
...
direction
...
nrot,all
...
!Rotate
...
nodes
...
into
...
the
...
active
...
coordinate
...
system
...
nplo
...
!Now
...
see
...
that
...
the
...
constraints
...
are
...
what
...
you
...
wanted
...
2.
...
I'd
...
like
...
to
...
plot
...
the
...
von
...
Mises
...
stress
...
for
...
selected
...
areas
...
in
...
a
...
3D
...
model.
...
I
...
select
...
the
...
nodes
...
attached
...
to
...
these
...
areas
...
using
...
select
...
logic.
...
However,
...
then
...
I
...
do
...
a
...
contour
...
plot
...
of
...
the
...
nodal
...
solution
...
(PLNSOL),
...
it
...
seems
...
to
...
plot
...
the
...
stress
...
for
...
all
...
the
...
areas,
...
not
...
just
...
the
...
selected
...
surfaces.
...
How
...
do
...
I
...
plot
...
stresses
...
only
...
for
...
the
...
selected
...
areas?
...
Yes
...
that
...
is
...
the
...
way
...
it
...
is
...
supposed
...
to
...
work.
...
To
...
get
...
closer
...
to
...
what
...
you
...
want,
...
you
...
should
...
select
...
the
...
area,
...
select
...
the
...
nodes
...
attached
...
to
...
that
...
area,
...
then
...
select
...
the
...
elements
...
attached
...
to
...
those
...
nodes.
...
3.
...
I
...
have
...
a
...
list
...
of
...
x,y,z
...
coordinates
...
in
...
a
...
text
...
file.
...
How
...
can
...
I
...
read
...
these
...
into
...
ANSYS
...
to
...
create
...
keypoints?
...
This
...
can
...
be
...
done
...
using
...
the
...
Ansys
...
APDL
...
functions.
...
Look
...
in
...
the
...
APDL
...
manual
...
for
...
a
...
complete
...
description.
...
Here
...
is
...
a
...
brief
...
exercpt
...
from
...
section
...
3.11.5.4
...
which
...
shows
...
how
...
to
...
read
...
data
...
into
...
an
...
array
...
parameter.
...
You
...
can
...
fill
...
an
...
array
...
from
...
a
...
data
...
file
...
using
...
the
...
*VREAD
...
command
...
(Utility
...
Menu>Parameters>Array
...
Parameters>Read
...
from
...
File).
...
The
...
command
...
reads
...
information
...
from
...
an
...
ASCII
...
data
...
file
...
and
...
begins
...
writing
...
it
...
into
...
the
...
array,
...
starting
...
with
...
the
...
index
...
location
...
that
...
you
...
specify.
...
You
...
can
...
control
...
the
...
format
...
of
...
the
...
information
...
read
...
from
...
the
...
file
...
through
...
data
...
descriptors.
...
The
...
data
...
descriptors
...
must
...
be
...
enclosed
...
in
...
parenthesis
...
and
...
placed
...
on
...
the
...
line
...
following
...
the
...
*VREAD
...
command.
...
See
...
Vector
...
Operations
...
for
...
more
...
information
...
about
...
data
...
descriptors.
...
The
...
data
...
descriptors
...
control
...
the
...
number
...
of
...
fields
...
to
...
be
...
read
...
from
...
each
...
record,
...
the
...
width
...
of
...
the
...
data
...
fields,
...
and
...
the
...
position
...
of
...
the
...
decimal
...
point
...
in
...
the
...
field.
...
For
...
example,
...
given
...
the
...
following
...
data
...
file
...
named
...
dataval:
...
1.5
...
7.8
...
12.3
...
15.6
...
-45.6
...
42.5
...
and
...
an
...
array
...
called
...
EXAMPLE
...
that
...
has
...
been
...
dimensioned
...
as
...
2
...
x
...
3,
...
the
...
following
...
commands
...
(provided
...
as
...
either
...
a
...
part
...
or
...
a
...
macro
...
or
...
input
...
listing)
...
*DIM,EXAMPLE,,2,3
...
*VREAD,EXAMPLE(1,1),dataval,,,JIK,3,2
...
(3F6.1)
...
result
...
in
...
EXAMPLE
...
=
...
1.5
...
7.8
...
12.3
...
15.6
...
-45.6
...
42.5
...
4.
...
If
...
I
...
wanted
...
to
...
create
...
two
...
keypoints
...
at
...
(1.5,
...
7.8,
...
12.3)
...
and
...
(15.6,
...
-45.6,
...
42.5)
...
using
...
the
...
array
...
parameter
...
EXAMPLE
...
in
...
question
...
3,
...
how
...
would
...
I
...
do
...
it?
...
I
...
am
...
able
...
to
...
create
...
them
...
one-by-one
...
for
...
each
...
element
...
of
...
the
...
array
...
but
...
that
...
becomes
...
tedious
...
when
...
I
...
have
...
a
...
lot
...
of
...
rows
...
in
...
the
...
table.
...
For
...
automatic
...
keypoint
...
numbering
...
you
...
could
...
use:
...
num=2
...
!
...
set
...
this
...
to
...
be
...
the
...
number
...
of
...
rows
...
of
...
data
...
in
...
EXAMPLE
...
csys,0
...
!
...
or
...
whatever
...
coordinate
...
system
...
you
...
want
...
to
...
use
...
*do,jj,1,num
...
k,,example(jj,1),example(jj,2),example(jj,3)
...
*enddo
...
For
...
user
...
controlled
...
keypoint
...
numbering
...
change
...
"k,,"
...
to
...
"k,xx+jj,'
...
and
...
set
...
xx
...
before
...
the
...
do
...
loop
...
as
...
the
...
starting
...
keypoint
...
number.
...
For
...
example,
...
if
...
you
...
issue
...
xx=100,
...
then
...
keypoints
...
will
...
be
...
created
...
as
...
101,102,103,....