[ahvz]

Hello,
I have been working on transient analysis with considering the below code but I have strange results. is there anyone to help me to find my problem?

(indeed I divide the temperature profile to some branches to get accurate fitting curve, that's why I have more than one equation in the code)

/***********************************************************************
UDF example.c 
UDF for specifying transient temperature profile boundary condition S
 ************************************************************************/
#include "udf.h"
#include "mem.h"
DEFINE_PROFILE(TempS_Profile, thread, position)    
{
real x[ND_ND];                                       
real y; 
real t1=10019;
real t2=13529;
real t3=20009;
real t4=29999;
real t5=40019;
real t6=50009;
real t7=59999;
real t8=70019;
real t9=80009;

real theProfile;
face_t f;
begin_f_loop(f, thread);
 {
 F_CENTROID(x,f,thread);
 y = CURRENT_TIME;     
  
     if(y<=t1) 
      {       
       theProfile=(-2E-13*pow(y,3.))+(3E-08*pow(y,2.))+(9E-06*pow(y,1.))+283.78; 
       F_PROFILE(f, thread, position) =theProfile;    
       }
      else if (y<=t2 && y>t1)
       {
       theProfile=(1E-11*pow(y,3.))-(4E-07*pow(y,2.))+(0.0061*pow(y,1.))+257.77;  
       F_PROFILE(f, thread, position) =theProfile;
       }
       else if (y<=t3 && y>t2)
       {
       theProfile=(-4E-11*pow(y,3.))+(2E-06*pow(y,2.))-(0.035*pow(y,1.))+482.71;  
       F_PROFILE(f, thread, position) =theProfile;
       }
       else if (y<=t4 && y>t3)
       {
       theProfile=(4E-12*pow(y,3.))-(3E-07*pow(y,2.))+(0.0091*pow(y,1.))+203.7;  
       F_PROFILE(f, thread, position) =theProfile;
       }
       else if (y<=t5 && y>t4)
       {
       theProfile=(-7E-12*pow(y,3.))+(7E-07*pow(y,2.))-(0.0233*pow(y,1.))+550.94;  
       F_PROFILE(f, thread, position) =theProfile;
       }
       else if (y<=t6 && y>t5)
       {
       theProfile=(9E-12*pow(y,3.))-(1E-06*pow(y,2.))+(0.0575*pow(y,1.))+566.62;  
       F_PROFILE(f, thread, position) =theProfile;
       }
       else if (y<=t7 && y>t6)
       {
       theProfile=(1E-12*pow(y,3.))-(2E-07*pow(y,2.))+(0.0094*pow(y,1.))+171.39;  
       F_PROFILE(f, thread, position) =theProfile;
       }
       else if (y<=t8 && y>t7)
       {
       theProfile=(-6E-12*pow(y,3.))+(1E-06*pow(y,2.))-(0.0849*pow(y,1.))+2180.8;  
       F_PROFILE(f, thread, position) =theProfile;
       }
       else if (y<=t9 && y>t8)
       {
       theProfile=(-1E-11*pow(y,3.))+(3E-06*pow(y,2.))-(0.2083*pow(y,1.))+5510.9;  
       F_PROFILE(f, thread, position) =theProfile;
       }
       else
       {
       theProfile=(-6E-11*pow(y,3.))+(1E-05*pow(y,2.))-(1.2143*pow(y,1.))+33813;  
       F_PROFILE(f, thread, position) =theProfile;
       }
 }
end_f_loop(f,thread)
}

regards,