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Old   July 16, 2014, 21:13
Default Heat flux profile UDF
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Mohamed
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Hi everyone, I want to write an UDF that allow me to change the profile of the heat flux on a solar PANEL, using an equation as shown in the attached image, and another shows the computational domain and the boundary conditions .
Well, I wrote a UDF but when I compiled present errors, I can not fix them.
So please help me to find the right text of my UDF.
Greetings.

HTML Code:
#include "udf.h"
DEFINE_PROFILE(heatflux_profile, t, F, i)    
{              
face_t f; 
real It=750;                       
real H=232000;
real Tam=300;
real Tm=298.6;
real Ul=20;
real Eta=0.16;
real m=2;
real cs=1.4;
real cl=1.8;
real temp;
temp = F_T(f,t);
real Time;
Time = RP_Get_Real("physical-time-step");
begin_f_loop(f, t)
 {   
    if((temp>Tam) && (temp<Tm)
           F_PROFILE(f,t,i) = Ul*(temp*Tam) *time+Eta*It*Time+m*cs*(temp-Tam);
    else if(temp==Tm)
           F_PROFILE(f,t,i) = Ul*(temp*Tam)*time+Eta*It*Time+m*cs*(Tm-Tam)+H;
    else(temp>Tm)
           F_PROFILE(f,t,i) = Ul*(temp*Tam)*time+Eta*It*Time+m*cs*(Tm-Tam)+H+m*cl*(temp-Tm);
 }
end_f_loop(f,t)
}
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File Type: jpg BIPV.jpg (30.6 KB, 7 views)
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Old   July 17, 2014, 18:26
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Syavash
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Quote:
Originally Posted by B.Hamada View Post
Hi everyone, I want to write an UDF that allow me to change the profile of the heat flux on a solar PANEL, using an equation as shown in the attached image, and another shows the computational domain and the boundary conditions .
Well, I wrote a UDF but when I compiled present errors, I can not fix them.
So please help me to find the right text of my UDF.
Greetings.

HTML Code:
#include "udf.h"
DEFINE_PROFILE(heatflux_profile, t, F, i)    
{              
face_t f; 
real It=750;                       
real H=232000;
real Tam=300;
real Tm=298.6;
real Ul=20;
real Eta=0.16;
real m=2;
real cs=1.4;
real cl=1.8;
real temp;
temp = F_T(f,t);
real Time;
Time = RP_Get_Real("physical-time-step");
begin_f_loop(f, t)
 {   
    if((temp>Tam) && (temp<Tm)
           F_PROFILE(f,t,i) = Ul*(temp*Tam) *time+Eta*It*Time+m*cs*(temp-Tam);
    else if(temp==Tm)
           F_PROFILE(f,t,i) = Ul*(temp*Tam)*time+Eta*It*Time+m*cs*(Tm-Tam)+H;
    else(temp>Tm)
           F_PROFILE(f,t,i) = Ul*(temp*Tam)*time+Eta*It*Time+m*cs*(Tm-Tam)+H+m*cl*(temp-Tm);
 }
end_f_loop(f,t)
}
Hi,
Define_profile should only have three arguments. So you must delete "F" from the argument list of the macro.
Goodluck
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Old   July 17, 2014, 20:37
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Mohamed
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Quote:
Originally Posted by syavash View Post
Hi,
Define_profile should only have three arguments. So you must delete "F" from the argument list of the macro.
Goodluck
Thank you for your reply, but when I delete F, and when I interpreted Fluent UDF. message appears as follows:

temp definition shadows previous definition
Error: C:\Users\khaoula\Desktop\prof.c: line 16: parse error.
Error: C:\Users\khaoula\Desktop\prof.c: line 17: Time: undeclared variable

Please tell me what i supposed to do.
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Old   July 18, 2014, 06:40
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Quote:
Originally Posted by B.Hamada View Post
Thank you for your reply, but when I delete F, and when I interpreted Fluent UDF. message appears as follows:

temp definition shadows previous definition
Error: C:\Users\khaoula\Desktop\prof.c: line 16: parse error.
Error: C:\Users\khaoula\Desktop\prof.c: line 17: Time: undeclared variable

Please tell me what i supposed to do.
Just try to rename "temp" to something else; e.g. temp1.
Bests
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Old   July 18, 2014, 12:26
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Quote:
Originally Posted by syavash View Post
Just try to rename "temp" to something else; e.g. temp1.
Bests
I do it, but now this error appear.
HTML Code:
Error: C:\Users\khaoula\Desktop\prof.c: line 16: c_t: undeclared variable
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Old   July 18, 2014, 14:26
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Quote:
Originally Posted by B.Hamada View Post
I do it, but now this error appear.
HTML Code:
Error: C:\Users\khaoula\Desktop\prof.c: line 16: c_t: undeclared variable
Modify your UDF as follows:


#include "udf.h"
DEFINE_PROFILE(heatflux_profile, t, i)
{
face_t f;
real It=750;
real H=232000;
real Tam=300;
real Tm=298.6;
real Ul=20;
real Eta=0.16;
real m=2;
real cs=1.4;
real cl=1.8;
real temp1;
real Time;
Time = RP_Get_Real("physical-time-step");
begin_f_loop(f, t)
{

temp1 = F_T(f,t);
if((temp>Tam) && (temp<Tm)
F_PROFILE(f,t,i) = Ul*(temp*Tam) *time+Eta*It*Time+m*cs*(temp-Tam);
else if(temp==Tm)
F_PROFILE(f,t,i) = Ul*(temp*Tam)*time+Eta*It*Time+m*cs*(Tm-Tam)+H;
elseif(temp>
Tm)
F_PROFILE(f,t,i) = Ul*(temp*Tam)*time+Eta*It*Time+m*cs*(Tm-Tam)+H+m*cl*(temp-Tm);
}
end_f_loop(f,t)
}
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Old   July 18, 2014, 17:38
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Mohamed
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Quote:
Originally Posted by syavash View Post
Modify your UDF as follows:


#include "udf.h"
DEFINE_PROFILE(heatflux_profile, t, i)
{
face_t f;
real It=750;
real H=232000;
real Tam=300;
real Tm=298.6;
real Ul=20;
real Eta=0.16;
real m=2;
real cs=1.4;
real cl=1.8;
real temp1;
real Time;
Time = RP_Get_Real("physical-time-step");
begin_f_loop(f, t)
{

temp1 = F_T(f,t);
if((temp>Tam) && (temp<Tm)
F_PROFILE(f,t,i) = Ul*(temp*Tam) *time+Eta*It*Time+m*cs*(temp-Tam);
else if(temp==Tm)
F_PROFILE(f,t,i) = Ul*(temp*Tam)*time+Eta*It*Time+m*cs*(Tm-Tam)+H;
elseif(temp>
Tm)
F_PROFILE(f,t,i) = Ul*(temp*Tam)*time+Eta*It*Time+m*cs*(Tm-Tam)+H+m*cl*(temp-Tm);
}
end_f_loop(f,t)
}
Thank you friend for your help.
So, a new error now appear.

HTML Code:
Error: C:\Users\khaoula\Desktop\prof.c: line 22: temp: no function prototype
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Old   July 18, 2014, 18:07
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Quote:
Originally Posted by B.Hamada View Post
Thank you friend for your help.
So, a new error now appear.

HTML Code:
Error: C:\Users\khaoula\Desktop\prof.c: line 22: temp: no function prototype
I forgot to rename all the "temp" in your code. Just rename the remaining "temp"s to "temp1".
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Old   July 18, 2014, 18:11
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Mohamed
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Quote:
Originally Posted by syavash View Post
I forgot to rename all the "temp" in your code. Just rename the remaining "temp"s to "temp1".
Hi, i do this but now a new error.
PHP Code:
ErrorC:\Users\khaoula\Desktop\prof.cline 17Timeundeclared variable 
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Old   July 18, 2014, 18:34
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Quote:
Originally Posted by B.Hamada View Post
Hi, i do this but now a new error.
PHP Code:
ErrorC:\Users\khaoula\Desktop\prof.cline 17Timeundeclared variable 
Please change "time" to "Time" everywhere in your code.
P.S.: Remember that C/C++ language is case sensitive.
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Old   July 18, 2014, 20:10
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Quote:
Originally Posted by syavash View Post
Please change "time" to "Time" everywhere in your code.
P.S.: Remember that C/C++ language is case sensitive.
the same problem.
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Old   July 18, 2014, 21:39
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Quote:
Originally Posted by B.Hamada View Post
the same problem.
OK, try to rename all the "Time" to something else, like "Time1".
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