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Old   July 29, 2013, 11:43
Default same velocity in inlets
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rayan
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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 :

HTML Code:
#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
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Old   July 29, 2013, 15:58
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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,
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Old   July 29, 2013, 17:14
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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?
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Old   July 30, 2013, 03:41
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Quote:
Originally Posted by rayan24 View Post
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,
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Old   July 30, 2013, 03:46
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Thanks for your response
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Old   November 19, 2013, 07:41
Default Udf
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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.
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