[B.Hamada]

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.

#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)
}

[syavash]

Originally Posted by B.Hamada

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.

#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

[B.Hamada]

Originally Posted by syavash

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.

[syavash]

Originally Posted by B.Hamada

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

[B.Hamada]

Originally Posted by syavash

Just try to rename "temp" to something else; e.g. temp1.
Bests

I do it, but now this error appear.

Error: C:\Users\khaoula\Desktop\prof.c: line 16: c_t: undeclared variable

[syavash]

Originally Posted by B.Hamada

I do it, but now this error appear.

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)
}

[B.Hamada]

Originally Posted by syavash

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.

Error: C:\Users\khaoula\Desktop\prof.c: line 22: temp: no function prototype

[syavash]

Originally Posted by B.Hamada

Thank you friend for your help.
So, a new error now appear.

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".

[B.Hamada]

Originally Posted by syavash

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:

Error: C:\Users\khaoula\Desktop\prof.c: line 17: Time: undeclared variable 


[syavash]

Originally Posted by B.Hamada

Hi, i do this but now a new error.

PHP Code:

Error: C:\Users\khaoula\Desktop\prof.c: line 17: Time: undeclared variable 


Please change "time" to "Time" everywhere in your code.
P.S.: Remember that C/C++ language is case sensitive.

[B.Hamada]

Originally Posted by syavash

Please change "time" to "Time" everywhere in your code.
P.S.: Remember that C/C++ language is case sensitive.

the same problem.

[syavash]

Originally Posted by B.Hamada

the same problem.

OK, try to rename all the "Time" to something else, like "Time1".