TALK=T;RUN(1,1) 719.htm
```
#cls
text(In-Form Equivalent Of PLANT Case Z119
title
libref=719
DISPLAY

This In-Form case does what Z119 does, namely solves a 2D unsteady
diffusion problem and compares the result with the exact solution.

First, case z119 is loaded.
Then NAMSAT = NONE is set, in order to deactivate PLANT entries, and
the space and time intervals are increased in order to make the
comparison with the exact solution more meaningful.

Thereafter the following In-Form formulae provide the boundary
conditions, the volumetric source and the exact solution:

(SOURCE of C1 at IWESt is 2.*(TIM*YG^2-C1)/DXG with line)
(SOURCE of C1 at IEAST is 2.*(TIM*(1.0+YG^2)-C1dgr)/DXG with line)
(SOURCE of C1 at ISOUTH is 2.*(TIM*XG^2-C1)/DYG with line)
(SOURCE of C1 at iNORTH is 2.*(TIM*(1.0+XG^2)-C1)/DYG with line)
(SOURCE of C1 at iSOURC is XG^2+YG^2-4.*TIM)
(STORED of EXAC is TIM*(XG^2+YG^2))

The Q1 contains PHOTON USE commands
ENDDIS
PHOTON USE
p

msg             Numerical solution  contours
msg                     Time=1.
con C1 Z 1 fi;0.001
msg Press Enter to continue
PAUSE
CLEAR
con EXAC Z 1 fi;0.001
msg               Exact solution  contours
msg                      Time=1.
msg Press e to END
ENDUSE

text(In-Form equivalent of PLANT case Z119
libref=719

INFORM13BEGIN
** The next line de-activates PLANT **
namsat=none
SOURC=SKIP
COVAL(WEST,C1,0.,0.);COVAL(EAST,C1,0.,0.)
COVAL(SOUTH,C1,0.,0.);COVAL(NORTH,C1,0.,0.)
INFORM13END

** The following settings have been chosen as being
preferable to those of z119, in respect of convergence
and printout.                                         **
LSWEEP=100
NX=50;NY=50
LSTEP=20
#UNIGRID
** In-Form formulae which are equivalent to the
PLANT formulae of z119
INFORM13BEGIN
PATCH(IWEST,WWALL,1,1,1,NY,1,NZ,1,LSTEP)
(SOURCE of C1 at IWESt is 2.*(TIM*YG^2-C1)/DXG with line)

PATCH(IEAST,EWALL,NX,NX,1,NY,1,NZ,1,LSTEP)
(SOURCE of C1 at IEAST is 2.*(TIM*(1.0+YG^2)-C1)/DXG with line)

PATCH(ISOUTH,SWALL,1,NX,1,1,1,NZ,1,LSTEP)
(SOURCE of C1 at ISOUTH is 2.*(TIM*XG^2-C1)/DYG with line)

PATCH(INORTH,NWALL,1,NX,NY,NY,1,NZ,1,LSTEP)
(SOURCE of C1 at INORTH is 2.*(TIM*(1.0+XG^2)-C1)/DYG with line)

PATCH(ISOURC,VOLUME,1,NX,1,NY,1,NZ,1,LSTEP)
(SOURCE of C1 at ISOURC is XG^2+YG^2-4.*TIM)
INFORM13END
INFORM7BEGIN
(STORED of EXAC is TIM*(XG^2+YG^2))
INFORM7END
DISTIL=T
EX(C1)=6.626E-01; EX(EXAC)=6.650E-01
STOP
```