[rayan24]

I want to impose by UDF a same velocity profile in 3 inlets, but i don't get same velocity in the 3 inlets apparently i impose my profile in function of the distance r!!

how can i impose my velocity profile in the "surface" of inlet to get samevelocity please??

my udf is :

#include "udf.h"
DEFINE_PROFILE(w_velocity_inlet,t,i)
{
real x[ND_ND]=3; /* this will hold the position vector */
real r;
face_t f;
begin_f_loop(f,t)
{
F_CENTROID(x,f,t);
r = x[0];
F_PROFILE(f,t,i) = -((0.0431*pow(r,3))-(0.3857*pow(r,2))+(0.3129*r)+8.8045);
}
end_f_loop(f,t)

thanks

[Amir]

Dear Rayan,

Your profile is a function of x-coordinate, so you will get different results if the elements of these inlets have different x positions! Did you expect something else?!

Bests,

[rayan24]

Tank you Amir for your replay,

My 3 inlets are aligned in the XY plane, so the Inlet 1 ranges between x = [1, 4.5], inlet 2 is between x = [5, 7.5] and the inlet 3 is between x = [5, 7.5], so I can't get to impose my velocity profile in each inlet!

Do you have an idea please?

[Amir]

Originally Posted by rayan24

Tank you Amir for your replay,

My 3 inlets are aligned in the XY plane, so the Inlet 1 ranges between x = [1, 4.5], inlet 2 is between x = [5, 7.5] and the inlet 3 is between x = [5, 7.5], so I can't get to impose my velocity profile in each inlet!

Do you have an idea please?

Hi,

There are lots of options. You can either use if-clauses to switch between different thread IDs or simply use 3 UDFs.

Bests,

[rayan24]

Thanks for your response

[Mohammad80]

Hello Amir,
Could you please help me?
I have a problem writing a UDF for my 2D-geometry.
I hope you have time to contact me at my E.mail address:
mas20001920@yahoo.com

Best regards.