Hi, I got this error when I write my own code. It's look strange because the syntax I think is correct. The error exist in this part
auE_h=(-uCe,(uDx-uCe)/2,0)
Any help will be great thank you and here I posted the whole code
PROGRAM BACKWARD
IMPLICIT NONE
! Declaration parameter
! INTEGER TYPE
INTEGER, PARAMETER :: NX=300
INTEGER, PARAMETER :: NY=30
INTEGER dx, dy, i,j, maxIter, maxNMiter, n
! REAL TYPE
REAL, PARAMETER :: L=15
REAL, PARAMETER :: H=1
REAL(8) alpha_u, alpha_p, Cs, err, Ho, Hs, nu, Re, uMax
REAL(8) uCe, uCw, uCn, uCs !CONVECTIVE TERM PARAMETER FOR u
REAL(8) vCe, vCw, vCn, vCs !CONVECTIVE TERM PARAMETER FOR v
REAL(8) dudy, dudx, nutu !SGS CLASSIC SMAGORINSKY PARAMETER for u
REAL(8) dvdy, dvdx, nutv !SGS CLASSIC SMAGORINSKY PARAMETER for v
REAL(8) uDx, uDy !DIFFUISIVE TERM PARAMETER for u
REAL(8) vDx, vDy !DIFFUISIVE TERM PARAMETER for v
! REAL TYPE WITH DIMENSION
REAL, DIMENSION(NX+1,NY+2) :: u, uold, ustar, uprime
REAL, DIMENSION(NX+2,NY+1) :: v, vold, vstar, vprime
REAL, DIMENSION(NX+2,NY+2) :: p, pstar, pprime
REAL, DIMENSION(1,NY+2) :: uLeft
REAL, DIMENSION(1,NY+2) :: vLeft
REAL(8) auE_h, auW_h, auN_h, auS_h
REAL, DIMENSION(NX,NY) ::auE
REAL, DIMENSION(NX,NY) ::auW
REAL, DIMENSION(NX,NY) ::auN
REAL, DIMENSION(NX,NY) ::auS
REAL, DIMENSION(NX,NY) ::auP
REAL, DIMENSION(NX,NY) ::dU
REAL, DIMENSION(NX,NY) ::dV
REAL(8) avE_h, avW_h, avN_h, avS_h
REAL, DIMENSION(NX,NY) ::avE
REAL, DIMENSION(NX,NY) ::avW
REAL, DIMENSION(NX,NY) ::avN
REAL, DIMENSION(NX,NY) ::avS
REAL, DIMENSION(NX,NY) ::avP
REAL(8) apE_h, apW_h, apN_h, apS_h
REAL, DIMENSION(NX,NY) ::apE
REAL, DIMENSION(NX,NY) ::apW
REAL, DIMENSION(NX,NY) ::apN
REAL, DIMENSION(NX,NY) ::apS
REAL, DIMENSION(NX,NY) ::apP
REAL, DIMENSION(NX,NY) ::bpP
REAL, DIMENSION(NX,NY) ::ux ! Convergence coeff
REAL, DIMENSION(NX,NY) ::uxold
REAL, DIMENSION(NX,NY) ::vx
REAL, DIMENSION(NX,NY) ::vxold
REAL(8) cmax_1, cmax_2, convergence !CONVERGENCE
REAL, DIMENSION(1,NY) ::Y
! FILL THE VALUE
maxIter=50000 !INTEGER VALUE
maxNMiter=1
alpha_u=0.3 !REAL VALUE
alpha_p=0.7
Cs=0.07
err=1e-5
Ho=1.0
Re=100
nu=2e-3
dx=L/NX
dy=H/NY !Step size
Hs=H-Ho
uMax=Re*nu/Hs
! ALLOCATE THE GUESS VALUE AND INITIAL CONDITION
u(:,:)=0
uold(:,:)=0 !INITIAL CONDITION
ustar(:,:)=0
uprime(:,:)=0
dU(:,:)=0
v(:,:)=0
vold(:,:)=0 !INITIAL CONDITION
vstar(:,:)=0
vprime(:,:)=0
dV(:,:)=0
p(:,:)=0
pstar(:,:)=0
pprime(:,:)=0
uLeft(:,:)=0
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!! SIMPLE SCHEME APPLY FROM HERE &
!!!! CLASSIC SMAGORINSKY SGS
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
DO n=1,maxIter
! STEP 1a, solve x-momentum as ustar
DO i=2,NX
DO j=2,NY+1
! Convective flux terms use CENTRAL DIFFERENCE
uCe=dy*0.5*(uold(i,j)+uold(i+1,j))
uCw=dy*0.5*(uold(i,j)+uold(i-1,j))
uCn=dx*0.5*(vold(i,j)+vold(i,j+1))
uCs=dx*0.5*(vold(i,j-1)+vold(i+1,j-1))
! Calculation for rate of strain tensor
dudy=(0.5*(uold(i,j)+uold(i,j+1)))/dy
dudy=(0.5*(uold(i,j)+uold(i+1,j)))/dx
nutu=(Cs*FLOAT(dx))**2*((0.5*(dudx+dudy)**2)**0.5)*(dudx+dudy)
! Diffusive flux term
uDx=(FLOAT(dy)/FLOAT(dx)*((1/Re)+nutu))
uDy=(FLOAT(dx)/FLOAT(dy))*((1/Re)+nutu)
! ASSEMBLY COEFFICIENT FROM HYBRID SCHEME
auE_h=(-uCe,(uDx-uCe)/2,0)
auW_h=(uCw, (uDx+0.5*uCw), 0)
auN_h=(-uCn, (uDy-0.5*uCn), 0)
auS_h=(uCs, (uDy+0.5*uCs), 0)
auE(i,j)=MAX(auE_h)
auW(i,j)=MAX(uCw, (uDx+0.5*uCw), 0)
auN(i,j)=MAX(-uCn, (uDy-0.5*uCn), 0)
auS(i,j)=MAX(uCs, (uDy+0.5*uCs), 0)
!Central coeff & under relaxation
auP(i,j)=(auE(i,j)+auW(i,j)+auN(i,j)+auS(i,j))/alpha_u
!Velocity component for PCE
dU(i,j)=FLOAT(dy)/auP(i,j)
END
END
!Use uold for calculate ustar
ustar=uold
DO iter=maxNMiter
DO i=2, NX
DO j=2, NY+1
ustar(i,j)=(auE(i,j)*ustar(i+1,j)+auW(i,j)*ustar(i-1,j)+auN(i,j)*ustar(i,j+1)+auS(i,j)*ustar(i,j-1)-FLOAT(dy)*(pstar(i+1,j)-pstar(i,j))+(1-alpha_u)*auP(i,j)*uold(i,j))/auP(i,j)
END
END
END
! ustar FOR X-MOMENTUM HAS BEEN SOLVE
!!!!!!!!!! STEP 1B BEGIN
! Solve y-momentum as vstar
DO i=2, NX+1
DO j=2, NY
! Convective flux terms use CENTRAL DIFFERENCE
vCe=dy*0.5*(uold(i,j)+uold(i,j+1))
vCw=dy*0.5*(uold(i-1,j)+uold(i-1,j+1))
vCn=dx*0.5*(vold(i,j)+vold(i,j+1))
vCs=dx*0.5*(vold(i,j)+vold(i,j-1))
! Calculation for rate of strain tensor
dvdy=(0.5*(vold(i,j)+vold(i,j+1)))/dy
dvdy=(0.5*(vold(i,j)+vold(i+1,j)))/dx
nutv=(Cs*FLOAT(dx))**2*((0.5*(dvdx+dvdy)**2)**0.5)*(dvdx+dvdy)
! Diffusive flux term
vDx=(FLOAT(dy)/FLOAT(dx))*((1/Re)+nutv)
vDy=(FLOAT(dx)/FLOAT(dy))*((1/Re)+nutv)
! ASSEMBLY COEFFICIENT FROM HYBRID SCHEME
avE_h=(-vCe, (vDx-0.5*vCe), 0)
avW_h=(vCw, (vDx+0.5*vCw), 0)
avN_h=(-vCn, (vDy-0.5*vCn), 0)
avS_h=(vCs, (vDy+0.5*vCs), 0)
avE(i,j)=MAX(avE_h)
avW(i,j)=MAX(avW_h)
avN(i,j)=MAX(avN_h)
avS(i,j)=MAX(avS_h)
!Central coeff & under relaxation
avP(i,j)=(avE(i,j)+avW(i,j)+avN(i,j)+avS(i,j))/alpha_u
!Velocity component for PCE
dV(i,j)=FLOAT(dx)/avP(i,j)
END
END
! Calculate vstar
vstar=vold
DO iter=maxNMiter
DO i=2, NX+1
DO j=2, NY
vstar(i,j)=(avE(i,j)*vstar(i+1,j)+avW(i,j)*vstar(i-1,j)+avN(i,j)*vstar(i,j+1)+avS(i,j)*vstar(i,j-1)-FLOAT(dy)*(pstar(i+1,j)-pstar(i,j))+(1-alpha_u)*avP(i,j)*vold(i,j))/avP(i,j)
END
END
END
! vstar has been calculated, move to next step
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!! STEP 2 CALCULATE PRESSURE CORRECTION
DO i=2, NX+1
DO j=2, NY+1
! Boundary coefficient
apE(i,j) = dU(i,j)*dy
apW(i,j) = dU(i-1,j)*dy
apN(i,j) = dV(i,j)*dx
apS(i,j) = dV(i,j-1)*dx
! Central coefficient
apP(i,j) = apE(i,j)+apW(i,j)+apN(i,j)+apS(i,j)
! RHS value
bpP(i,j)= (ustar(i-1,j)-ustar(i,j))*dy+(vstar(i,j-1)-vstar(i,j))*dx
END
END
!! APPLY BOUNDARY CONDITION FOR PRESSURE
IF (n==1 .AND. i=2 .AND. j=2) THEN
apP(i,j)=1.0
apE(i,j)=0
apW(i,j)=0
apN(i,j)=0
apS(i,j)=0
bpP(i,j)=0
END
!!Calculate pprime
pprime(:,:)=0
DO iter=maxNMiter
DO i=2, NX+1
DO j=2, NY+1
pprime(i,j)=
pprime(i,j)=(apE(i,j)*pprime(i+1,j)+apW(i,j)*pprime(i-1,j)+apN(i,j)*pprime(i,j+1)+apS(i,j)*pprime(i,j-1)+bpP(i,j)/apP(i,j)
END
END
END
!!!!!!!!!! pprime has been calculated move to next section
!!!!!!!!!! STEP 3 CALCULATE VELOCITY CORRECTION
!! u-velocity correction
DO i=2, NX
DO j=2, NY+1
uprime(i,j)=dU(i,j)*(pprime(i,j)-pprime(i+1,j))
END
END
!! v-velocity correction
DO i=2, NX+1
DO j=2, NY
vprime(i,j)=dV(i,j)*(pprime(i,j)-pprime(i,j+1))
END
END
!!!!!! STEP 3 FINISH MOVE TO STEP 4
!!!!!! STEP 4 CALCULATE REAL u,v, and p
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!! CALCULATE REAL u
Do i=2, NX
Do j=2, NY+1
u(i,j)=ustar(i,j)+uprime(i,j)
END
END
!! CALCULATE REAL v
Do i=2, NX+1
Do j=2, NY
v(i,j)=vstar(i,j)+vprime(i,j)
END
END
!! CALCULATE REAL p
Do i=2, NX+1
Do j=2, NY+1
p(i,j)=pstar(i,j)+pprime(i,j)*alpha_p
END
END
!!!!!!! STEP 4 FINISH !!!!!!!!!!
!!!!!!! STEP 5 ITERATION UNTIL CONVERGENCE
!!!!!!!
ux=u(1:NX+1, 1:NY+1)
uxold=uold(1:NX+1, 1:NY+1)
vx=v(1:NX+1, 1:NY+1)
vxold=vold(1:NX+1, 1:NY+1)
cmax1=MAX(MAX(ux-uxold))
cmax2=MAX(MAX(vx-vxold))
convergence=MAX(cmax1, cmax2)
IF convergence<err THEN
STOP
ELSE
uold=u
vold=v
pstar=p
!!!!!!!! CONVERGENCE CRITERIA IS SET
!!!!!!!! STEP 6 PROBLEM SET UP
!!!!!! APPLY INLET VELOCITY FUNCTION
DO j=NY+1, 2, -1
Y(1,j)=(1, H:-dy:0)
IF Y(1,j)<Ho THEN
uLeft(1,j)=4*umax*(Y(i,j)/Ho)*(1-(Y(1,j)/Ho))
vLeft(1,j)=0
ELSE IF Y(1,j)>Ho THEN
uLeft(1,j)=0
vLeft(1,j)=0
END
END
!!!!!! APPLY BOUNDARY CONDITION FOR VELOCITY
uold(:,1)=0.0 !bottom bound
vold(:,1)=0.0
uOld(:,Ny+2) = 0.0
vOld(:,Ny+1) = 0.0
uOld(1,:) = uLeft(1,:)
vOld(:,1) = vLeft(:,1)
uOld(Nx+1,:) = uOld(Nx,:)
vOld(Nx+2,:) = vOld(Nx+1,:)
END
END
END
END
END PROGRAM BACKWARD-
