# fortran Code for a boundary layer on a plate

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 April 4, 2013, 16:16 fortran Code for a boundary layer on a plate #1 Member   shahrbanoo Join Date: Mar 2013 Posts: 63 Rep Power: 13 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...

 April 4, 2013, 16:20 #2 Member   shahrbanoo Join Date: Mar 2013 Posts: 63 Rep Power: 13 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

 April 4, 2013, 16:21 #3 Member   shahrbanoo Join Date: Mar 2013 Posts: 63 Rep Power: 13 !************************************************* ********************** 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)

 April 18, 2018, 15:53 #4 Senior Member   Have a nice time! Join Date: Feb 2016 Location: mech.eng.ahmedmansour@gmail.com Posts: 291 Rep Power: 11 Hello, have you run this code? Thanks

 April 19, 2018, 00:57 #5 Senior Member     Uwe Pilz Join Date: Feb 2017 Location: Leipzig, Germany Posts: 744 Rep Power: 15 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. __________________ Uwe Pilz -- Die der Hauptbewegung überlagerte Schwankungsbewegung ist in ihren Einzelheiten so hoffnungslos kompliziert, daß ihre theoretische Berechnung aussichtslos erscheint. (Hermann Schlichting, 1950)

 April 20, 2018, 12:13 #6 Senior Member   Have a nice time! Join Date: Feb 2016 Location: mech.eng.ahmedmansour@gmail.com Posts: 291 Rep Power: 11 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!

April 20, 2018, 14:02
#7
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Uwe Pilz
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Quote:
 Originally Posted by Ahmed Saeed Mansour 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.
__________________
Uwe Pilz
--
Die der Hauptbewegung überlagerte Schwankungsbewegung ist in ihren Einzelheiten so hoffnungslos kompliziert, daß ihre theoretische Berechnung aussichtslos erscheint. (Hermann Schlichting, 1950)

 April 20, 2018, 16:01 #8 New Member   CFlr Join Date: Feb 2018 Location: FRG Posts: 5 Rep Power: 8 You could check the Book of Cebeci and Bradshaw, which also discusses this topic. Ahmed Saeed Mansour likes this.

April 20, 2018, 17:21
#9
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Quote:
 Originally Posted by piu58 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.
Okay sir, I sent my e-mail to you,
Vielen Dank!

April 20, 2018, 23:51
#10
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Truong Dang
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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.
Attached Files
 Similarity_solution_laminar_flat_plate.zip (1.6 KB, 39 views)

 April 21, 2018, 01:19 #11 Senior Member     Uwe Pilz Join Date: Feb 2017 Location: Leipzig, Germany Posts: 744 Rep Power: 15 I sent you the file. Much success! Ahmed Saeed Mansour likes this. __________________ Uwe Pilz -- Die der Hauptbewegung überlagerte Schwankungsbewegung ist in ihren Einzelheiten so hoffnungslos kompliziert, daß ihre theoretische Berechnung aussichtslos erscheint. (Hermann Schlichting, 1950)

April 21, 2018, 12:01
#12
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Quote:
 Originally Posted by ssh123 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.
Thank you very much !!! I really appreciate that!

April 21, 2018, 12:03
#13
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Quote:
 Originally Posted by piu58 I sent you the file. Much success!
Vielen Dank!

 April 21, 2018, 23:06 #14 New Member   Truong Dang Join Date: Oct 2016 Location: Vietnam Posts: 21 Rep Power: 9 You are welcome.

April 21, 2018, 23:09
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Truong Dang
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Quote:
 Originally Posted by Ahmed Saeed Mansour Thank you very much !!! I really appreciate that!
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.