/com  quartz tube external pressure buckling (from STAR/al_150_long.1.txt) 
/com	qt3= round tube, thick endcaps, axial pressure, ball ends, 
/com 	SI units
/com	This model includes maximum ovality and bow according to mfr's specification
p=100000	!unit force 1 bar
t=.003		!tube thickness
r=.0195		!tube radius, nom
l=1.2		!tube length (has now changed to 1.35 (for inverted design)
rtol=.0002	!std ovality tolerance is 1/2 OD tol.(0.8mm) = 0.4mm(D) = 0.2mm(R)
ltol=.0015*l	!annealed/m; unannealed is 1mm/m, we  
lc=(ltol**2+l**2)/(2*ltol)
par1=(r-rtol)/r	!ellipticity parameter for elliptical coord. sys.
ndiv_long=100	!number of longitudinal elements
ndiv_circ=24	!must be even number
f=3.14159*(r+0.5*t)**2*p	!end force, unit load


/prep7
/view,1,.5,.5,1
/pbc,all,1
/title, NEXT quartz tube (42mm OD x 3mm thk.),0.4mm oval, 1.8mm bow, nonlinear buckling
/com    buckling analysis for NEXT WLS tube, from external pressure loading
/com 	code written for ansys 11

/com ELEMENT TYPES (nl layer shell elements)
/com ET, ITYPE, Ename, KOP1, KOP2, KOP3, KOP4, KOP5, KOP6, INOPR
et,1,63		!general shell 3d
/com          Real Set 1  al/pitch carbon composite
/com             layer thicknesses

mp,ex,1,72.4e9	!quartz elestic modulus
mp,prxy,1,0.17	!quartz poissons's ratio

/com	Real constants = shell element thicknesses
r,1,t
r,2,10*t	!make end cap elements 10x thicker (leave elastic modulus same as quartz for now)

/com               COORDINATE SYSTEM DEFINITIONS

csys,1	!1=cyl, z=axis
/com               CYLINDER BODY DEFINITION
mat,1
type,1
real,1
/com	Define keypoints
k,1
k,2,r
k,33,r,90
k,5,,,l
k,6,lc-ltol,90,l/2

/com 	define cylindrical (w/elliptical option) coord. system using keypoints
/com	CSKP, KCN, KCS, PORIG, PXAXS, PXYPL, PAR1, PAR2
cskp,11,1,1,2,33,par1

k,3,r,90
k,4,r,180
k,44,r,270

/com	draw lines to keypoints, with divisions, finer at ends)
l,2,3,ndiv_circ/2
l,3,4,ndiv_circ/2
l,4,44,ndiv_circ/2
l,44,2,ndiv_circ/2
/com	l,1,5,ndiv_long,-3
/com	LARC, P1, P2, PC, RAD
larc,1,5,6,lc
/com	LESIZE, NL1, SIZE, ANGSIZ, NDIV, SPACE, KFORC, LAYER1, LAYER2, KYNDIV
LESIZE,5,,,ndiv_long,-3

/com	ADRAG, NL1, NL2, NL3, NL4, NL5, NL6, NLP1, NLP2, NLP3, NLP4, NLP5, NLP6
adrag,1,2,3,4,,,5
amesh,all
/com	LESIZE, NL1, SIZE, ANGSIZ, NDIV, SPACE, KFORC, LAYER1, LAYER2, KYNDIV
l,1,2	!l11
l,1,3	!l12
l,1,4	!l13
l,1,44!114
l,5,7
l,5,8
l,5,9
l,5,10

LESIZE,all,,,0.5*ndiv_circ
al,15,1,14
al,16,2,15
al,17,3,16
al,14,4,17

al,18,6,19
al,21,13,18
al,20,11,21
al,19,9,20
real,2
amesh,5,12

nrotate,all
/com	DK, KPOI, Lab, VALUE, VALUE2, KEXPND, Lab2, Lab3, Lab4, Lab5, Lab6
dk,1,ux,0,,,uy,uz
dk,5,ux,0,,,uy
/com	fk,5,fz,-f	!unit end load(comment out to use presure load)
/com	sfa,all,2,pres,20*p	!max pressure load(comment out to use force)
save
/com	SFA, AREA, LKEY, Lab, VALUE, VALUE2
fini

/solu
ANTYPE,0
nlgeom,on
pstress,on
sstif,on
solcontrol,on
nropt,unsym,,off
AUTOTS,on
LNSRCH,0
NEQIT,5   
PRED,0  
TIME,10
DELTIME,0.5,0.05,0.5,on 
/GO
kbc,0
SFA,all,2,PRES,1000*p 
OUTPR,all,none   
OUTRES,ALL,ALL 
OUTPR,STAT  
OUTRES,STAT 
/STATUS,SOLU
SOLVE   
fini
/eof