# I want a Fortran code simulating Poiseuille flow.

hello all
I started in fortran and I’m blocked

I want a FORTRAN code simulating Poiseuille flow.
I search a code simulating of a [size=large]Poiseuille flow in FORTRAN code[/size].
is of extreme urgency.

I have this code for the couette flow and I want a code for the Poiseuille flow !!!
I can not find the definition of the geometry

``````
PROGRAM COUETTE
DIMENSION U(101)
COMMON/TDMA/A(101),B(101),C(101),D(101)
C-----IMAX IS NUMBER OF GRID LINES
IMAX=20
WRITE(6,*) 'HERE 1'
C-----ISKIP IS THE LINES SKIPPED BETWEEN PRINTOUT
ISKIP=1
IM1=IMAX-1
C-----BOUNDRARY CONDITIONS
U(1)=0.0
U(IMAX)=1.0
C-----EVALUATION OF TDMA COEFFICIENTS
DY=1./FLOAT(IM1)
DO 10 I=2,IM1
AI=FLOAT(I)
Y=(AI-1.5)*DY
A(I)=EXP(1.92*(1.-Y))
Y=(AI-.5)*DY
C(I)=EXP(1.92*(1.-Y))
B(I)=-A(I)-C(I)
10      D(I)=0.0
WRITE(6,*) 'HERE 1'
C-----CALL THE TRIDIAGONAL ALGORITHM TO OBTAIN VELOCITIES
CALL TRIDIA(1,IMAX,U)
C-----PRINTOUT OF VALUES
WRITE(6,1000)
WRITE(6,1001) (I,U(I),I=1,IMAX,ISKIP)
PAUSE
1000   FORMAT('VELOCITY DISTIBUTION BETWEEN PLATES *****'
1/'       I         U(I)')
1001   FORMAT(I4,5X,F10.5)
END
C
C*****TRIDIAGONAL SUBSUBROUTINE WHERE 'IT' IS THE LAST LINE, 'IB' IS
C     THE FIRST LINE AND 'PHI' IS THE DEPENDENT VARIABLE THE
C     NOMENCLATURE CORRESPONDS TO EQNS 16-48 THRU 16-53 IN THE C NEXT
SUBROUTINE TRIDIA (IB,IT,PHI)
DIMENSION E(101),F(101),PHI(IT)
COMMON/TDMA/A(101),B(101),C(101),D(101)
IM1=IT-1
IP1=IB+1
IP2=IB+2
WRITE(6,*) 'HERE 1'
C-----SETTING UP BOUNDARY VALUES
D(IP1)=D(IP1)-A(IP1)*PHI(IB)
A(IP1)=0.0
D(IM1)=D(IM1)-C(IM1)*PHI(IT)
C(IM1)=0.0
E(IP1+1)=-C(IP1)/B(IP1)
F(IP1+1)=D(IP1)/B(IP1)
C-----EVALUATION OF E'S AND F'S
DO 20 K=IP2,IM1
FAC=1./(A(K)*E(K)+B(K))
E(K+1)=-C(K)*FAC
20     F(K+1)=(D(K)-A(K)*F(K))*FAC
C-----USING E'S AND F'S TO CALCULATE PHI
PHI(IM1)=F(IT)
DO 30 L=IP2,IM1
LL=IT+IP1-L
30     PHI(LL-1)=E(LL)*PHI(LL)+F(LL)
RETURN
END

``````

big thank you to everyone
big thank you to everyone
big thank you to everyone