```

PHOTON USE
p

5 1

msg Circular pipe
msg radial direction magnified by factor of 5
gr y m
msg Press  to continue
pause
gr y m
msg Concentration contour of particle 1
msg in various z planes
con pt1 z 1 fi;0.01
con pt1 z 4 fi;0.01
con pt1 z 7 fi;0.01
con pt1 z 10 fi;0.01
msg Press  to continue
pause
cl
gr y m
msg Concentration contour of particle 2
msg in various z planes
con pt2 z 1 fi;0.01
con pt2 z 4 fi;0.01
con pt2 z 7 fi;0.01
con pt2 z 10 fi;0.01
msg Press e to END
enduse

GROUP 1. Run title and other preliminaries
TEXT(3D flow in a circular pipe: P110
TITLE
DISPLAY
3-dimensional, polar, steady, elliptic simulation

This case calculates the accumulation of two groups of particles,
of different diameters, along the bottom of a circular pipe
through which liquid flows from low z to high z. The particle
slip velocities are normal to the continuous phase flow direction.

enddis

GROUP 3. X-direction grid specification
CARTES=F
nx=10; xulast=2.0*3.1416; ny=5; yvlast=0.25; nz=11; zwlast=5.5
#unigrid
#aslp0
npt=2
GROUP 7. Variables stored, solved & named
#aslp1
.... slab-wise solution faster in this case
solutn(p1,y,y,n,p,p,p);solutn(u1,y,y,n,p,p,p)
solutn(v1,y,y,n,p,p,p);solutn(w1,y,y,n,p,p,p)
store(imb1)
GROUP 9. Properties of the medium (or media)
data input 2
dens0=1.e3 ; diam0=1.0  ;  visc0=1.e-5
dens1=2.e3 ; diam1=1.e-4;  visc1=2.5E-6; VFRAC1=0.1
dens2=2.e3 ; diam2=2.E-5;  visc2=2.5E-6; VFRAC2=0.1
end data input 2
#aslp2
GROUP 11. Initialisation of variable or porosity fields
REAL(UIN); UIN=1.0
FIINIT(P1)=1.E4; FIINIT(U1)=0.0; FIINIT(V1)=0.0; FIINIT(W1)=UIN
FIINIT(PT0)=VFRAC0; FIINIT(PT1)=VFRAC1; FIINIT(PT2)=VFRAC2
GROUP 13. Boundary conditions and special sources
** Inlet
PATCH(ASMIN,LOW,1,NX,1,NY,1,1,1,LSTEP)
COVAL(ASMIN, P1 ,FIXFLU, UIN*RHOM)
COVAL(ASMIN,PT0 ,ONLYMS, VFRAC0)
COVAL(ASMIN,PT1 ,ONLYMS, VFRAC1)
COVAL(ASMIN,PT2 ,ONLYMS, VFRAC2)
COVAL(ASMIN, W1 ,ONLYMS, UIN)
COVAL(ASMIN,VFOL,ONLYMS, 1.0/RHOM)
** Outlets
PATCH(ASMOU1,HIGH,1,NX,1,NY,NZ,NZ,1,LSTEP)
COVAL(ASMOU1,P1,1.E-1,0.0)
** Gravity
#gravity
gravdir=2
#density

GROUP 15. Termination of sweeps
LITER(PT0)=2; LITER(PT1)=5
ENDIT(PT0)=1.E-8; ENDIT(PT1)=1.E-5
LSWEEP=35
RESREF(P1)=1.E-8; RESREF(U1)=1.e-8
RESREF(V1)=1.e-8; RESREF(W1)=1.e-8
RESREF(PT0)=1.E-8;RESREF(PT1)=1.e-8
RESREF(PT2)=1.e-8
GROUP 17. Under-relaxation devices
RELAX( P1,LINRLX,1.0);RELAX( U1,FALSDT,1.0)
RELAX( V1,FALSDT,1.0);RELAX( W1,FALSDT,1.0)
RELAX(PT0,LINRLX,0.7);RELAX(PT1,LINRLX,0.7)
GROUP 22. Spot-value print-out
TSTSWP=-1
GROUP 23. Field print-out and plot control
IPLTF=2;IPLTL=LSWEEP;YZPR=F;IPROF=1
IXMON=NX/2; IYMON=NY/2; IZMON=NZ/2; NXPRIN=1; NYPRIN=1; NZPRIN=1
GROUP 24. Dumps for restarts

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