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HSeldon February 12, 2007 14:56

Fluent variables
Hi all, I need to get the values of the lift and grad coeff in order to complete an UDF. What are the name for those variables to include them in my UDF??

Thanks in advance.

Rizwan February 12, 2007 23:31

Re: Fluent variables
Can u please be a bit more elobarate? As far as I can guess, if u need to calculate drag force, then u need to find pressure distrution on the surface or region and multiply it with area vector.

force = 0.0 begin_f_loop (f, t)


F_AREA (A, f, t);

force = force + F_P (f, t) * NV_MAG (A);

} end_f_loop (f, t)

HSeldon February 13, 2007 11:04

Re: Fluent variables
Sorry for been so "short" in my explanation. Yes, basically I need what you put. Because I need to write into a file the Cd and/or Cl value to a txt. I know that fluent can do it, but this excersise is for college in order to practice C language and UDF stuff.

Regarding the code you put above: What F_P does? (pressure?)

Thank you for the input Rizwan!!

Rizwan February 13, 2007 13:44

Re: Fluent variables
F_P is the built in macro that will find pressure on the face and is available from solver whenevr it is called from the udf.


HSeldon February 13, 2007 14:14

Re: Fluent variables
Thank you very much!

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