Learning Forum

[jgrani6]

Hello, I am trying to model a thin walled pressure vessel using axisymmetric option for solid element. I have a set of lines which draw the outer edge. I've done it with shell elements easily, I now want to model it using Solid 182 elements using axisymmetric option. However, I need to mesh area for plane elements. How do I add thickness to my lines so that instead of lines, I have 2d areas that still draw the outer edge?

Thanks

[jgrani6]

This is in Mechanical APDL

[wrbulat]

Please try this test case I created then see if you can apply this strategy to your model:

fini
/cle

/vie,1,1,1,1

/pnu,kp,1


C*** PARAMETERS
r=0.5 ! END RADIUS
l=1 ! LENGTH OF STRAIGHT SECTION BETWEEN SPHERICAL ENDS
t=0.10 ! PRESSURE VESSEL WALL THICKNESS


C*** PRESSURE VESSEL EXTERNAL SURFACE
/prep7

wpcs,-1,0
wpof,,-l/2
cswp,11,1
k,1,r,-90
k,2,r,0
l,1,2

wpof,,l
cswp,12,1
k,3,r
k,4,r,90
l,3,4

csys
l,2,3

lplo

/wait,2


C*** CREATE AREA REPRESENTING PRESSURE VESSEL WALL CROSS SECTION
allsel
numc,line
csys
*get,ymin,kp,,mnloc,y
*get,ymax,kp,,mxloc,y
kgen,2,kp(0,0,ymin),,,0,0,t,500
l,kp(0,0,ymin),kp(0,0,ymin)+500
*get,lmax,line,,num,max
adrag,all,,,,,,lmax
aoff,all,-t,1000

lsel,s,loc,z
asel,none
l,kp(0,ymin,0),kp(0,ymin,0)+1000
l,kp(0,ymax,0),kp(0,ymax,0)+1000
al,all

cm,keep_a,area
cm,keep_l,line

alls
cmse,u,keep_a
cmse,u,keep_l
adel,all,,,1
ldel,all,,,1

alls
aplo

Best Bill