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Jihwan January 24, 2007 10:15

udf
 
Temp Gradient in UDF

Hi

I have a problem accessing the temperature gradient in a UDF.

I want to give temperature gradient on the 2-D wall.

(Methematical fucntion is T(x)= 30 + ( 1.5 * lxl )

I am writing using DEFINE_PROFILE.

I just following UDF manuals Ex.

But my udf file didn't warking.

I didn't know what is problem.. becuz I'm rookie on fluent.

Could anyone help me in this

*** cpp file (made by me) ***

#include "udf.h"

DEFINE_PROFILE(wall_temp,thread,index) {

real x[ND_ND];

real temp;

face_t f;

begin_f_loop(f,thread)

{

temp = F_T(f,thread);

F_UDMI(f,thread,0) = 30 + (1.5 * x );

if (x < 1)

x * = - 1

}

end_f_loop(f,t) }

Sujith January 24, 2007 15:39

Re: udf
 
there are errors in the udf. F_UDMI(f,thread,0) is reqd. only if a user defined memory is not needed for storing some information.

begin_f_loop(f,thread) will loop over all the faces where you are hooking the udf.

get the centroid of each face using the macro F_CENTROID(x,f,thread)

u will get x,y,z coordinates as x[0],x[1],x[2]

then define your profile F_PROFILE(f,t,i) = f(x,y,z)

You may refer the documentations....

Best wishes, Sujith

Jihwan January 25, 2007 00:08

Re: udf
 
dear Sugith

Thanks for your advice.

I'll more try again.

Can I send mail to you when I have a problen about this?

Have a nice day.

Sujith January 25, 2007 09:17

Re: udf
 
most welcome

Jihwan January 29, 2007 09:59

Re: udf
 
hi Sujith

I tried again..

But I failed again..

I was so confuse.

can you help me?

I made new udf file...

even though that failed interpreted.

****************************************** #include <udf.h> #include <math.h>

DEFINE_PROFILE(temp_wall,thread,position) {

real x [ND_ND];

real r,z,y;

face_t f;

begin_f_loop(f,thread)

{

F_CENTROID(x,f,thread);

r=x[1];

r=sqrt(x*x);

F_PROFILE(f,thread,position)=30.+(1.5*r);

}

end_f_loop(f,thread) }

Jihwan January 29, 2007 10:54

Re: udf
 
Hi Sujith

I succeed interpreted.

But I failed the compiling..

I don't know what is problem..

************************************************** ** #include <udf.h>

DEFINE_PROFILE(temp_wall,thread,position) {

real x [ND_ND];

real a,y;

face_t f;

begin_f_loop(f,thread)

{

F_CENTROID(x,f,thread);

a=x[1];

F_T(f,thread)=30.+(1.5*fabs(a));

}

end_f_loop(f,thread) }

I need your help

Sujith January 29, 2007 11:51

Re: udf
 
What is the error message? Probly u will not be havin a recommended microsoft compiler for windows

Jihwan January 29, 2007 21:08

Re: udf
 
Message is

I succeed interpreted. but I failed compiling..

massage aappear after clik Load button at compiling.

"pening library "Temp_wall"...

Error: open_udf_library: can't not found file.

Error Object: ()"

And I use visual c++



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