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GROUP 1. Run title and other preliminaries
TALK=F;RUN(1,1)
TEXT(2DXZ Duct Flow; Effect Of Pr No. USP Test 14
TITLE
DISPLAY
This run illustrates what happens when a fluid enters a duct
between two plane walls which are held at unequal temperatures.
Interesting parametric variations include: entry values of the
scalar variables; an additional boundary condition at the entry
section which would give the central region of the stream
a different set of values of the scalars; change to a flux
boundary  condition on one of the walls; and the introduction of
temperature- dependent transport properties.
/    /|
Wall     /    / |
at temp---/    /  |
T1     /    /   |
/    /    |
|    |Wall |
Fixed     | ^  |at   |
mass,     |/   |temp |
momentum, /    |T2   |
enthalpy /| ^  |    /
and conc- |/   |   / ^
entration /    |  / /z
fluxes   /| ^  | / /
|/   |/ /
x--->
ENDDIS

GROUP 3. X-direction grid specification
IREGX=1; GRDPWR(X,10,0.01,1.0)

GROUP 5. Z-direction grid specification
**In addition to pressure, two velocities and enthalpy, three
additional scalar quantities, C1, C2 and C3, are solved for. They
can be regarded as concentrations of substances which dissolve
in the fluid, differing only in their diffusion coefficient.
IREGZ=1; GRDPWR(Z,20,1.0,1.0)

GROUP 7. Variables stored, solved & named
SOLVE(P1,U1,W1,C1,C2,C3)
GROUP 8.
USP    = T
UAUTO  = F
USPDBG = F
UTCPLT = T
USPVTK = T
USPIMB = F
MXLEV  = 0
MYLEV  = 0
MZLEV  = 0
DOMAT  = -1
MINPRP = -1
MAXPRP = 250
CELLST = 10
FACEST = 10
USPREL = 0.75
PARSOL = F

GROUP 9. Properties of the medium (or media)
DEN1 = 1.
ENUL = 1.E-3
PRNDTL(C1)=1.0; PRNDTL(C2)=0.1; PRNDTL(C3)=10.0

GROUP 13. Boundary conditions and special sources
PATCH (WESTWALL,WWALL,1,1,1,1,1,NZ,1,1)
COVAL(WESTWALL,C1,1./PRNDTL(C1),0.0)
COVAL(WESTWALL,C2,1./PRNDTL(C2),0.0)
COVAL(WESTWALL,C3,1./PRNDTL(C3),0.0)
COVAL(WESTWALL,W1,1.0,0.0)

PATCH (EASTWALL,EWALL,NX,NX,1,1,1,NZ,1,1)
COVAL(EASTWALL,C1,1.0,1.0)
COVAL(EASTWALL,C2,10.0,1.0)
COVAL(EASTWALL,C3,0.1,1.0)
COVAL(EASTWALL,W1,1.0,0.0)

PATCH(OUT,HIGH,1,NX,1,NY,NZ,NZ,1,1)
COVAL(OUT,P1,1.e+3,0.)

**Uniform inflow at low boundary
PATCH(IN,LOW,1,NX,1,1,1,1,1,1)
COVAL(IN,P1,FIXFLU,10.0)
COVAL(IN,W1,0.,10.0)
COVAL(IN,C1,1.,0.5)
COVAL(IN,C2,1.,0.5)
COVAL(IN,C3,1.,0.5)

mesg(Do you want to use collocated arrangement (y) or staggered one (n)? (y/n)
if(:ans:.eq.y)then
SPEDAT(SET,USP,METHOD,I,1)
RELAX(P1  ,LINRLX, 1.000000E-01)
RELAX(U1  ,FALSDT, 1.000000E+02)
RELAX(V1  ,FALSDT, 1.000000E+02)

mesg(Do you want to use SIMPLEST (y) or SIMPLE (n)? (y/n)
if(:ans:.eq.y)then
SPEDAT(SET,USP,SIMPLEST,L,T)
endif

endif

mesg(Do you want to view results in the centres of cells? (y/n)
if(:ans:.eq.y)then
SPEDAT(SET,USPIO,VERTCENT,L,F)
endif

GROUP 15. Termination of sweeps
LSWEEP=200
RESFAC = 1.E-6
GROUP 22. Spot-value print-out
IXMON=NX/2+13
mesg(Do you want to use max&min(y) on monitor instead of default(n)? (y/n)