CFD Online Discussion Forums - Compilation error in UDF for gas-solid fluidized bed

Hi all,

I am simulating a 2D gas-solid fluidized bed using eulerian/eulerian plus granular flow theory. I have two user-defined memory variables (C_UDMI(0) and C_UDMI(1)) and want to calculate C_UDMI(1) for each cell in my domain using C_UDMI(0) of adjacent cells.

I need to loop over all faces of a cell and find out if the solid mass flux is going into the cell or outside of it. If going into, then I will use the value of C_UDMI(0) of the adjacent cell to find out the C_UDMI(1) value. For this purpose I have written the following UDF:

Code:

DEFINE_ON_DEMAND(on_demand_calc)

{

     Domain *d; 

     Thread *mix, *par_t, *tf,  *t1;

     Thread **pt;

     cell_t c, c1;

     int n, m;



     d = Get_Domain(1);    

     m = 0;

   mp_thread_loop_c (mix,d,pt)

     {

          par_t=pt[1];      /* solid phase */

          begin_c_loop(c,par_t)

          {

               c_face_loop(c, par_t, n)  

               {

                  tf = C_FACE_THREAD(c, par_t, n); 

                    c1 = F_C1(tf, par_t);

                    t1 = F_C1_THREAD(tf, par_t);

                    if(F_FLUX(tf, par_t)<0)

                    {

                    C_UDMI(c, par_t, 1) += C_UDMI(c1, t1, 0);

                    m += 1;

                    }

               }

               if(m!=0)

               {

               C_UDMI(c, mix, 1) /= m;

               m = 0;

               }

               else

               {

                    C_UDMI(c, mix, 1) = -1;

               }

          }

          end_c_loop(c,par_t)

     }

}

When I try to interpret this UDF I get an error that "non-integer subscript expression: unsigned char." on the following line:

c_face_loop(c, par_t, n)

I would appreciate if you could check the issue and advice if I am going the right way or I have errors in the way of accessing data in my UDF.

Thanks
Amir