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Routine to calculate skin friction coefficient

Posted: Fri May 20, 2011 10:20 am
by Sébastien Thomas
Hello everybody,
 
I work on the version 1.3.3 and I search a routine or a programme for usproj to calculate skin friction coefficients for each cells of my object to verify different situations and the variables in Fortran of skin friction coefficient or the efforts to calculate the skin friction coefficient.
 
Do you have a solution for me please?
 
Thanks very much
 
Sebastien
 

Re: Routine to calculate skin friction coefficient

Posted: Tue May 24, 2011 10:19 am
by James McNaughton
Hi Sebastien,

The "efforts" as you describe are the sum of forces due to pressure, viscosity and turbulence and discussed in detail in the following thread on this forum:
http://code-saturne.org/forum/viewtopic.php?f=9&t=696

For skin friction you could use efforts and subtract pressure forces.

I've attached an alternate subroutine that one of my colleagues gave me previously who I'm sure won't mind me sharing, it is for the analysis of two cylinders so may not be perfect for what you like but will certainly help.

Thanks,

James

Re: Routine to calculate skin friction coefficient

Posted: Tue May 24, 2011 2:42 pm
by Sébastien Thomas
Hello James,
 
Thanks you for your answer but to complete the using of this subroutine, I need the subroutine usproj of your colleagues because he call the subroutine usproj to define many parameters in subroutine usproj_CF.
 
Thanks very much if you help me.
 
Sebastien

Re: Routine to calculate skin friction coefficient

Posted: Tue May 24, 2011 3:53 pm
by James McNaughton
The moments are: imom = 1 for u velocity, 2 for v velocity, 8 for pressure. You define them in usipsu of usini1.
I'm not sure what else you may need?
James

Re: Routine to calculate skin friction coefficient

Posted: Wed May 25, 2011 7:49 am
by Sébastien Thomas
Hello James,
 
Thanks for this answer, but to help I need to send me ths subroutines used in your case and notably the subroutines usproj and usini1 whose you used in subroutine usproj_Cf. Because I have different problem in compiling of correspondance in my subroutines.
 
Thanks you for your help
 
Sébastien

Re: Routine to calculate skin friction coefficient

Posted: Wed May 25, 2011 9:07 am
by James McNaughton
You should delete the following line which will be giving you a compile error:

Code: Select all

include "sstcas.h"
Everything else should work once you have modified to your specific case - if you have any other questions please let me know.

Thanks,

James

Re: Routine to calculate skin friction coefficient

Posted: Wed May 25, 2011 10:37 am
by Sébastien Thomas
Thanks james for your reply.
I have an other problem of compiling on usproj_Cf after modifications which you indicated me. I think that is certainly a problem of link but i don't see where. So i join my subroutines and my compiling file if you help me.
 
Thanks you very much.
Sébastien

Re: Routine to calculate skin friction coefficient

Posted: Wed May 25, 2011 1:18 pm
by James McNaughton
Apologies if there was some confusion by my renaming of usproj_CF - this
should be renamed usproj for compiling.
I think you are trying to compile with both usproj and usproj_CF in the FORT folder which is not possible.
You should copy the parts of usproj_CF that you require into your existing usproj file (or vice-versa) and make sure only one of them is in the FORT folder when you compile.
I think that should solve your problem.
Thanks,
James
 

Re: Routine to calculate skin friction coefficient

Posted: Fri Jun 10, 2011 10:07 am
by Sébastien Thomas
Thanks James for your reply,
 
I have my solution with your subroutin for my usproj and an adaptation to extract this data for skyn friction coefficient.
 
Thanks,
Sebastien