[farr24]

hi, I recently started using UDF and I have a lot of problems if someone can help me.
I have to create a UDF which will allow me to inject a heat source based on different parameters.the UDF that I create is this,
#include "udf.h"

DEFINE_heat(inlet_x_heat,thread)
{
real temp,volume,area,heat,alfv,NV_VEC(A);
real rhov = 999.6;
real rconst = 0.1;
real hfg = 2500;
real T_SAT = 18;
real x = 0.0132;
Thread *t;
cell_t c;
face_t f;


alfv= x/(0.622+x);
{
begin_c_loop(c,t)
{
temp = C_T(c,t);


if (temp > T_SAT)
{ heat = 0;}

else if(temp < T_SAT)
{ volume = C_VOLUME(c,t);
F_AREA(A,f,t);
area = NV_MAG(A);
area += NV_MAG(A);

heat =(rconst*alfv*rhov*(T_SAT-temp)*hfg*volume)/(area*T_SAT);
x=x-((rconst*alfv*rhov*(T_SAT-temp)*area*volume)/T_SAT);

}}

end_c_loop(c,t)}
return heat;

}
the problem is that the x changes for each cell according to the precedent x but not to the adjacent one.
thank you for your help