Selection of particular area Elements

Hello Adams

if the elems are associated to the surf, you can select elems by *createmark elems 1 'by surface' $surfID

but don't go around by such method because *createmark command provided many useful selection method like 'by box', 'by cylinder' 'by adjacent',...

hi tinh,

 

thanks for replying.

 

elements are not at all associated wit the surfaces...

 

and with the method of 'by box' , 'by cylinder' , 'by adjacent' selecting the elements is not accurate.

because i want the exact  selection of elements of particular area....and if i am selection that area manually then first i have to put the model in perfect view or place. then only i can select the elements.

specially this is the case of shafts as shown in attached figures.   

 

Regards

Adams

Hi

assume that you created the surface by 2 rings of nodes

if i had 2 rings of nodes, i can

- create center of first ring

- create center of second ring

- measure distance 2 center nodes (height)

- measure radius of rings

then put them in command *createmark elems 'by cylinder' center1_x center1_y center1_z center2_x center2_y center2_z radius height

i think this command work well in your case

hi tinh,

 

i had tried this concept...but there is some kind of problem occuring.

 

*createmark elems 1 'by cylinder' x y z i j k r h location contained all tol

 

'x y z 1 j k' values are achieved

also 'r h' values are achieved

 

now, location : inside / outside / boundary and acrossboundary.

        contained : 0

        all : 0

        tol : 0

 

 

but with this...full component elements is selected.....

Hi

check it again by create a cylinder from x y z to i j k with radius r and height h

if your elems are inside that cylinder then the command should work. i tested

*createmark elems 1 'by cylinder' $x $y $z $i $j $k $r $h inside 1 0 0

Hi,

 

i had created two centre nodes. and extracted the coordinated of it in the for of.

 

Centre node 1 : x y z

Centre node 2 : i j k

 

then calculated the radius with the edge node while using: set radius [hm_getdistance nodes $Centre_n1 $Edge_n1 0];

 

                                                                                            set height [hm_getdistance nodes $Centre_n2 $Centre_n1 0]

 

and putting these values for selecting the inside elements of the component.

 

 

eval *createmark elems 1 'by cylinder' $x $y $z $i $j $k $radius $height inside 1 0 0

 

 

but with this, all the internal elements got selected.

 

please reffer the attached figure.

 

 

results: 

 

Radius : 22.000600571600504 -8.272249507584775 9.59899999999999 17.984868990219866

 

Height : 7.200088058750607 6.5413229042695775 0.0001515303197834328 3.008714458515442

 

 

<?xml version="1.0" encoding="UTF-8"?>

Hi

the radius and height returned from hm_getdistance are lists, you need only first values to put in *createmark, they are actually radius and height

* commands usually do not throw errors for wrong arguments so you have to care about this

hi tinh,

 

To extract the first value of the radius and Height.

 

which command should i use? or i have to create the formulation.

 

 

as of now i had tried while creating the vector but its not working as well.

 

help me

Hi

it's a list so you can use 

set radius [lindex $radius 0]

=> so get first value of 'radius'

same for height

 

or extract it directly from first command forexample

 

set radius [lindex  [hm_getdistance nodes $Centre_n1 $Edge_n1 0] 0]

set height [lindex [hm_getdistance nodes $Centre_n2 $Centre_n1 0] 0]

hi tinh,

 

thanks. its really a great help.