/TITLE, Heat conduction in pipe, heatp2.a
  ! 3-in pipe insulated with 0.5-in asbestos and 2-in glass wool
  ! axial node numbering
  ! 4 axial elements in 8/100 ft gives 1/50 of heat per node
  ! nodal heats are per ring of elements of fixed x
  ! heat /foot of pipe is 50 time nodel heat
  ! exact solution = 78.35 BTU/hr-F-foot

/PREP7                    ! preprocessor section
tempin=400                ! fluid temperature
tempout=100               ! outside temperature

ET,1,PLANE55,,,1          ! axisymmetric option
MP,KXX,1,0.12             ! thermal conductivity, asbestos
MP,KXX,2,0.032            ! thermal conductivity, glass wool

len = 8/100               ! pipe length
rad1 = 1.5/12             ! pipe radius
rad2 = (1.5+0.5)/12       ! interface radius
rad3 = (1.5+0.5+2)/12     ! insulation outside radius
elax = 4                  ! axial number of elements
nax = elax+1              ! axial number of nodes
elra1 = 2                 ! radial number of elements, first insul
elra2 = 3                 ! radial number of elements, second insul
nrad1 = elra1+1           ! radial number of nodes, first insul
nrad2 = elra2+1           ! radial number of nodes, second insul
el10 = elra1*10+1

N,1,rad1,0                ! convert to feet
N,nax,rad1,len            ! upper-left node
FILL,1,nax                ! axial nodes
NGEN,nrad1,10,1,nax,1,(rad2-rad1)/elra1,0 ! first insul
NGEN,nrad2,10,el10,(el10+elax),1,(rad3-rad2)/elra2,0 ! 2nd insul
/PNUM,node,1              ! plot the nodes
NPLOT

TYPE,1                    ! element type (ET) 1
MAT,1                     ! material property MP 1
E,1,11,12,2               ! lower-left element
EGEN,elax,1,-1            ! axial elements, 1st insul
EGEN,elra1,10,-elax       ! first insul elements

MAT,2                     ! material property MP 2
E,el10,el10+10,el10+11,el10+1
EGEN,elax,1,-1            ! axial elements, 2nd insul
EGEN,elra2,10,-elax   ! first insul elements
EPLOT
OUTPR,,1
FINISH                    ! preprocessor section

/SOLUTION                 ! solution section
antype,static             ! analysis type is static
outpr,basic,1
outpr,nload,1
elfar = (elra1+elra2)*10+1
D,1,TEMP,tempin,,nax,1   ! temp of inside nodes
D,elfar,TEMP,tempout,,(elfar+elax),1  ! temp of outside nodes

SOLVE
EPLOT
FINISH                      ! solution section

/POST1          ! post processor
! /output,Temp,txt,D:\Ansys\   !  Temperature and heat
 /output,Temp,txt,U:\win\Ansys\   !  Temperature and heat
prnsol
prrsol
! FINISH          ! post processor

!  Number of       Heat   Interface %Error
!  radial elem              Temp
! insul1  insul2
!  exact         78.3498   370.11
!   1       1    81.1981   369.23   3.6
!   1       2    79.1681   370.00   1.0
!   2       2    79.1276   369.86   1.0
!   2       3    78.7104   370.02   0.46
!   2       4    78.5602   370.08   0.27
!   4       4    78.5499   370.04   0.26
!   2       5    78.4898   370.10   0.18
!   2       6    78.4514   370.12   0.13
!   3       6    78.4438   370.09   0.12
!   2       7    78.4282   370.13   0.10

! For 2 inner and 3 outer sets of elements
! 50*Node 2 = 100*Node 1 = 78.7 Btu/Hr
!      NODE   HEAT  
!        1  0.78710    
!        2   1.5742    
!        3   1.5742    
!        4   1.5742    
!        5  0.78710    
!       51 -0.78710    
!       52  -1.5742    
!       53  -1.5742    
!       54  -1.5742    
!       55 -0.78710    

!     NODE      TEMP  
!       1- 5   400.00  
!      11-15   383.94    
!      21-25   370.02    
!      31-35   258.17    
!      41-45   171.18    
!      51-55   100.00