! Ansys Structural Nonlinearities, Exercise Supplement 1
! Ref Training Manual Chapter 2

/prep7

! Element Types, Material Properties and Constants
et,1,56         ! HYPER56 2-D, 4-node, Mixed U-P, Hyperelastic Solid 
et,2,169        ! TARGE169 2-D Target Segment
et,3,171        ! CONTA171 2-D Surface-to-Surface Contact (no mid-side nodes)

mp,nuxy,1,.49       ! Material 1 Poisson's ratio

tb,mooney,1,2       ! Mooney-Rivlin hyperelastic constant from test data
tbdata,1,80
tbdata,2,20

mp,mu,1,.2          ! Coefficient of friction
r,1,,,.5,.1         ! Real constant for TARGE169
r,2,,,.5,.1         ! FKN = .5 Normal contact stiffness (scale factor)
                    ! FTOLN = .1 Defines the maximum penetration range (default)

! Define the seal geometry
k,1
k,,.333,0
k,3,.867,.867
k,4,1.1,.867
k,5,1.1,1
k,6,.8,1
k,7,.267,.133
k,8,0,.133
l,1,2
*repeat,7,1,1
l,8,1
lfil,1,2,.2
lfil,2,3,.15
lfil,5,6,.2
lfil,7,8,.05
lfil,8,1,.05
lfil,6,7,.15
al,all

! Define the lower boundary
k,25,-.6,0
k,26,1.1,0
lstr,26,25

! Define the upper boundary
k,27,-.6,1
k,28,1.1,1
lstr,27,28

! Refine the mesh in the fillet regions
lesi,8,,,2
lesi,13,,,4
lesi,14,,,4
esize,.035

! Mesh the rubber seal
type,1
mat,1
amesh,all

! Size the mesh of the rigid lower boundary
lesize,15,,,1
lesize,16,,,1
type,2
real,1
mat,1
lmesh,15


! Size the mesh lower portion of seal boundary
! and the upper outer radius
lsel,s,line,,1,3,1
lsel,a,line,,9,10,1
lsel,a,line,,14,14,1
nsll,s,1
type,3
esurf
lsel,all
type,2
real,2
lmesh,16

! Mesh the upper left KP of the fixed boundary
kmesh,27

! Mesh the remainder of the seal boundaries
lsel,s,line,,5,7,1
lsel,a,line,,11,13,1
nsll,s,1
type,3
esurf

lsel,all
nsel,all

! Define axissymetric constraint on vertical centerline
dl,4,,ux,0

! Get the node number at the upper left fixed boundary
*set,n_load,node(kx(27),ky(27),0)


fini
/solu

nlgeom,on               ! Non-linear geometry - large deflection/strain support

solc,on                 ! Soulution Control

time,.85                ! Used to keep track abs. displacement

d,n_load,uy,-.85        ! Displace upper rigid boundary down

nsubst,25,200,10        !  25 = # of substeps on 1st step.
                        ! 200 = max substeps for solution
                        !  10 = min substeps in solution

outres,all,all

monitor,var3,n_load,fy  ! MONITOR,VAR,Node,Lab: 3rd field in monitor is FY

solve

fini

/POST1
/EFACE,1
AVPRIN,0,0,
PLNSOL,U,SUM,2,1