fortran Code for a boundary layer on a plate
 

Hi...
I'm trying to undersatnd this code that our teacher gave us... he said to change one of the boundary conditions and then see how the result changes. This code's title is "LAMINAR BOUNDARY LAYER FLOW OVER AN ISOTHERMAL FLAT PLATE" . I don't understand what H, G, FPIN,... and other parameters, are. cause It's the first time I'm using a fortran code. I would really appreciate it if someone help me... .
I put the Code in the next post...

because it is too long,I have to split it into two parts:
!************************************************* ***********************
!***** *****
!***** SIMPLATE *****
!***** ________ *****
!***** *****
!************************************************* ***********************
!***** *****
!***** THIS PROGRAM GIVES SIMILARITY SOLUTION RESULTS FOR *****
!***** *****
!***** LAMINAR BOUNDARY LAYER FLOW OVER AN ISOTHERMAL FLAT PLATE *****
!***** *****
!************************************************* ***********************
!*
DIMENSION T(1500),F(1500),G(1500),H(1500),HGUESS(1500),FPIN(1500),P(1500)
!*
!************************************************* **********************
!*
OPEN(UNIT=1,FILE='SIMPLAPR.DAT',status='new')
OPEN(UNIT=2,FILE='SIMPLAPL.DAT',status='new')
!************************************************* **********************
WRITE(6,4250)
WRITE(6,4290)
WRITE(6,4260)
READ(5,*) PR
WRITE(6,4250)
DETA=0.01
N=1500
WRITE(1,4290)
WRITE(1,4270) PR
!************************************************* **********************
! N=NUMBER OF GRID POINTS
! PR=PRANDTL NUMBER
! DETA=ETA STEP SIZE
END

!************************************************* **********************
INTR=1
HGUESS(INTR)=1.0
100 F(1)=0.0
G(1)=0.0
H(1)=HGUESS(INTR)
DO 1000 I=2,N
F(I)=F(I-1)+G(I-1)*DETA
G(I)=G(I-1)+H(I-1)*DETA
H(I)=H(I-1)-F(I-1)*H(I-1)*DETA/2.0
1000CONTINUE
FPIN(INTR)=G(N)
IF(INTR.EQ.1)THEN
INTR=2
HGUESS(INTR)=HGUESS(1)-0.000001
GO TO 100
ELSE
IF(INTR.GT.200)GO TO 200
IF(ABS(1.0-FPIN(INTR)).LT.0.0000005)GO TO 300
INTR=INTR+1
DGUESS=+(FPIN(INTR-1)-1.0)*(HGUESS(INTR-1)-HGUESS(INTR-2))/(FPIN(INTR-2)-FPIN(INTR-1))
HGUESS(INTR)=HGUESS(INTR-1)+DGUESS
GO TO 100
ENDIF
200WRITE(6,2000)
GO TO 7777
300WRITE(6,3000) INTR
7777CONTINUE
DO 5000 I=1,N
P(I)=H(I)**PR
5000CONTINUE
T(1)=0.0
DO 6000 I=2,N
T(I)=T(I-1)+DETA*(P(I)+P(I-1))/2.0
6000CONTINUE
WRITE(1,4500)
DO 7000 I=1,N
T(I)=T(I)/T(N)
ETA=(I-1)*DETA
WRITE(1,4000) ETA,F(I),G(I),H(I),T(I)
WRITE(2,5500) ETA,G(I),T(I)
7000CONTINUE
TGRAD=(T(2)-T(1))/DETA
WRITE(1,4280) TGRAD
STOP
CLOSE(1)
CLOSE(2)
2000FORMAT(' FAILURE TO CONVERGE')
3000FORMAT(' CONVERGENCE IN ',I5,' ITERATIONS')
4000FORMAT(5F10.6)
4250FORMAT(////)
4260FORMAT(' INPUT THE VALUE OF THE PRANDTL NUMBER THEN ')
4270FORMAT(//,' PRANDTL NUMBER = ',F12.3,//)
4280FORMAT(//,' THETA GRADIENT AT WALL = ',F12.5)
4290FORMAT(/,' SIMILARITY SOLUTION FOR FLOW OVER ISOTHERMAL PLATE',//,'Output written to files SIMPLAPR.DAT and SIMPLAPL.DAT',//)
4500FORMAT(' ETA F dF/DETA D2F/DETA2 THETA')
5500FORMAT(F10.6,',',F10.6,',',F10.6)

Hello, have you run this code?
Thanks

Without analyzing the code en détail it looks like a realisation of the publication of Simon Ostrach "An analysis of laminar free-convection flow and heat transfer about a flat plate paralled to the direction of the generating body ".

All the variables look the the ones mentioned in the article. I wrote a smallish C++ program for it.

The most complicated point is to find the right boundary conditions, because one of the values are not known for t=0, but for t=infinity. You have to implement some kind of shooting method to find it form your material constants.

Thank you very much for the reply sir, is it okay to send me the code you typed by e-mail? I wanna learn how to write codes.
Could you help me?
Vielen Dank!

My code is commented in German and contains some code for the shooting method. It may be that you don't understand everything, simply because it has some experimental part in it.

Nevertheless, I send it. Please don't give it away. If somebody needs it, they may drop me a line.

You could check the Book of Cebeci and Bradshaw, which also discusses this topic.

Okay sir, I sent my e-mail to you,
Vielen Dank!

Hello,

Below is the Fortran source file for the code given by @shahrbanoo. I have to fix some typos in the code to make it work with gfortran.

I sent you the file. Much success!

Thank you very much !!! I really appreciate that!

Vielen Dank!

You are welcome.

You are welcome. I think to understand the code, the best way is firstly read the paper mentioned by @piu58, after that you shall be able to understand the code.